ifWBj
This is to certifq that the
thesis entitled

The Development and Fecundity of the
O rien tal F ru it Moth, Grapholltha
(Cydia) Moleata (Busck) Under Controlled
Temperatures and Hum idities.

x-^AV :

presented by

Ghulam-Ullah Chaudhry
has been accepted towards fulfillment
of the requirements for

Ph.D.

tn

Entomology

i ajor professor

July 13, 1951

0-169

mmmm
ssvssm

TH E D E V E L O P M E N T AN D FE C U N D IT Y O F T H E O R IE N T A L
F R U IT M O TH , G R A PH O L IT H A (CYDIA) M O LE ST A
(BUSCK) U N D E R C O N T R O L L E D
T E M P E R A T U R E S AND
H U M ID ITIES

By
G H U L A M -U L L A H CHAUDHRY

A TH ESIS
S u b m itte d to th e S c h o o l of G ra d u a t e S tu d ie s of M ic h ig a n
S ta te C o lle g e of A g r ic u ltu r e zmd A p p lie d S c ie n c e
in p a r t i a l f u lfillm e n t of th e r e q u ir e m e n ts
f o r th e d e g re e of

D O C TO R O F P H IL O SOPHY

D e p a r tm e n t of E n to m o lo g y

1951

A CK N O W LED G M EN TS

T h e w r i t e r w is h e s

o e x p r e s s h is s i n c e r e a p p r e c ia tio n

an d th a n k s to P r o f e s s o r R ay H u tso n , H e a d of th e D e p a r tm e n t
of E n to m o lo g y f o r g u id a n c e ,
c o u ra g e m e n t in th e conduc

c r i t i c i s m , h e lp a n d c o n s ta n t e n of th is w o rk .

T h e a u th o r i s f u r t h e r in d e b te d to D r. W. B . D re w , D r.
C. J . A le x o p o u lo s a n d D r. E . S. B e n e k e f o r th e u s e of t h e i r
in c u b a to r s ; to P r o f e s s o r D . C a tio n f o r h is a s s i s t a n c e in S u p p ly in g p e a c h s e e d lin g s a n d f o r p e r m i s s io n to re m o v e in f e s te d
tw ig s f r o m h is p e a c h n u r s e r i e s ; to D r.

W. D. B a te n f o r h e lp

in a n a ly z in g p a r t of th e da ;a s t a ti s t i c a ll y ; to D r. H. L . K ing
f o r r e a d in g th e m a n u s c r ip t c r i t ic a ll y ; to th e U n ite d S ta te s
W e a th e r B u r e a u a n d th e M e te o ro lo g ic a l D e p a rtm e n t of P a k is ta n
f o r f u r n is h in g m e te o r o lo g ic a l d a ta ; a n d to th e g ra d u a te s tu d e n ts
in th e E n to m o lo g y D e p a r tm e n t f o r c o o p e ra tio n d u rin g th e c o u rs e
of th e s e s tu d ie s .

VITA

G h u la m -U lla h C h a u d h ry
c a n d id a te f o r th e d e g re e of
D o c to r of P h ilo s o p h y
F in a l e x a m in a tio n , F r i d a y , J u ly 13,
N a tu r a l S c ie n c e B u ild in g .
D i s s e r ta tio n :

1951, 2:00 p . m . ,

245

T h e D e v e lo p m e n t a n d F e c u n d ity of th e O r ie n ta l
F r u i t M o th , G r a p h o lith a (C y d ia) m o le s ta (B u sck )
u n d e r C o n tr o lle d T e m p e r a tu r e s a n d H u m id itie s .

O u tlin e of S tu d ie s :
M a jo r s u b je c t: E n to m o lo g y .
M in o r s u b je c ts : B o ta n y , P la n t P a th o lo g y ,
H o r tic u ltu r e , S t a ti s t i c s .

M ycology,

B io g r a p h ic a l Ite m s :
B o rn ,

J a n u a r y 13,

1913, H o s h ia r p u r , In d ia .

U n d e rg ra d e a te S tu d ie s , U n iv e r s ity of th e P a n ja b ,

1929-33.

G ra d u a te S tu d ie s , In d ia n A g r i c u l t u r a l R e s e a r c h I n s titu te ,
N ew De h i, 193 6 -4 2 a n d 1947.
M ic h ig a n S ta te C o lle g e ,
E a s t L a n s in g , 1 9 4 9 -5 1 .

1

E x p e r ie n c e

i.
i i.
i ii .
iv .
v.
v i.
v ii.

L o c u s t R e s e a r c h A s s i s t a n t , 1 9 3 3 -3 4 .
F i e l d A s s i s t a n t (C o tto n ), 193 4 -3 6 .
A s s i s t a n t to th e I m p e r ia l E n to m o lo g is t,
1 9 3 6 -4 2 .
L o c u s t T e c h n ic a l o f f ic e r , 19 4 2 -4 4 .
E n to m o lo g is t, B a lu c h is ta n S ta te , 1 9 4 4 -4 7 .
T e c h n ic a l O f f ic e r , B u re a u of P la n t P r o ­
te c tio n a n d Q u a ra n tin e , In d ia , 1947.
A s s i s t a n t P l a n t P r o t e c t io n E n to m o lo g is t,
D e p t, of P l a n t P r o t e c t io n an d Q u a r ­
a n tin e , P a k is ta n , 1 9 4 7 -4 9 .

T H E D E V E L O P M E N T AN D FE C U N D IT Y O F TH E O R IE N T A L
F R U IT M O T H , G R A PH O L IT H A (CYDIA) M O LE ST A
(BUSCK) U N D E R C O N TR O LL E D
T E M P E R A T U R E S AND
H U M ID ITIES

By
G H U L A M -U L L A H CHAUDHRY

AN A B ST R A C T
S u b m itte d to th e S c h o o l of G ra d u a te S tu d ie s of M ic h ig a n
S ta te C o lle g e of A g r ic u ltu r e a n d A p p lie d S c ie n c e
in p a r t i a l f u lf illm e n t of th e r e q u ir e m e n ts
f o r th e d e g r e e of

D O C T O R O F PH ILO SO PH Y

D e p a r tm e n t of E n to m o lo g y

Y e a r 1951

A p p ro v e d_

G H U L A M -U L L A H CHAUDHRY

ABSTRACT

T h e d e v e lo p m e n t a n d fe c u n d ity of th e o r ie n ta l f r u i t m o th ,
G ra p h o lith a (C ydia) m o le s ta (B u sck ) w a s s tu d ie d u n d e r s e v e r a l
c o n tr o lle d t e m p e r a t u r e s of 50. 5° to 95° F . a n d r e la tiv e h u m id ­
i ti e s of 35% , 70% a n d 100% .

T h e o p tim u m ra n g e of t e m p e r ­

a tu r e f o r t h is i n s e c t w a s 7 5 ° - 8 5 ° F .
F . u n d e r h ig h h u m id itie s o n ly .

It c o u ld d e v e lo p a t 95°

T h e in c u b a tio n p e r io d w a s

lo w e s t u n d e r 70% r e l a ti v e h u m id ity a t t e m p e r a t u r e s of 65° to
95 ° F .

A t low t e m p e r a t u r e s of 5 0 .5 ° a n d 60° F . th e eg g s

d e v e lo p e d b e s t u n d e r 100% r e l a ti v e h u m id ity .

The eggs to l­

e r a t e d a n e x p o s u re of f o r ty h o u r s to 98° F . a n d tw e n ty -o n e
h o u r s to 105° F . ,

b u t t h e i r in c u b a tio n p e rio d i n c r e a s e d by

2 4 -4 0 h o u r s a s c o m p a r e d to th o s e k e p t th ro u g h o u t a t a n o p ti­
m u m te m p e ra tu re .
T h e t h r e s h o ld of d e v e lo p m e n t f o r e g g s w a s 40

o

a n d 44

F . ; f o r p u p ae 4 6 .5 ° a n d 5 2 .5 ° F . u n d e r r e la tiv e h u m id itie s
of 100% a n d 35% , r e s p e c t iv e ly .

F o r l a r v a e i t w a s 4 3 .5 ° F .

T he e g g s a n d p u p ae c a n d e v e lo p a t lo w e r t e m p e r a t u r e s w hen
e x p o s e d to h ig h h u m id ity th a n u n d e r low h u m id ity .
T h e l a r v a e of th e f r u i t m o th e n te r e d in to a s h o r t d ia ­
p a u s e f o r a p e rio d of 31 to 60 d a y s a n d in to a long d ia p a u se

o

vi
G H U LA M -U L 1L.AH CHAUDHRY

ABSTRACT

of o v e r 60 d a y s d u rin g S e p te m b e r to N o v e m b e r,

1950, u n d e r

v a r io u s c o n d itio n s of t e m p e r a t u r e a n d h u m id ity .

A s u b s ta n ­

t ia l ly l a r g e r n u m b e r of l a r v a e e n te r e d in to a n d c o m p le te d t h e i r
lo n g d ia p a u s e w hen th e r e l a ti v e h u m id ity to w h ic h th e y w e r e
e x p o s e d d u rin g th e c o co o n p e r io d w as h ig h e n o u g h .

G e n e r a lly

o u t of th e to ta l n u m b e r of m o th s e m e rg in g a t v a r io u s t e m p e r a ­
t u r e s a b o u t 50% , 33% a n d 0 .0 % m o th s e m e r g e d f r o m th e long
c y c le l a r v a e u n d e r r e l a ti v e h u m id itie s of 100% , 70% a n d 35% ,
r e s p e c t iv e ly .

T h is a d a p ta tio n e n s u r e s g r e a t e r s u r v iv a l f o r

th is s p e c ie s in r e g io n s w h e re a h ig h h u m id ity of 80-90% p r e ­
v a ils in la te s u m m e r a n d f a ll.
P h o to p e r io d is m d id n o t a ffe c t th e in d u c tio n o r d u r a tio n
o f l a r v a l d ia p a u s e a s th e l a r v a e w e n t in to h ib e r n a tio n e v e n w hen
g ro w n in d a r k n e s s .

T h e r e a l c a u s e w h ich i n i t i a t e s d ia p a u s e

m a y b e in h e r e n t.
T h e v ia b ility of th e p u p ae w as u s u a lly h ig h e s t u n d e r
s a t u r a t e d a tm o s p h e r e .

T he m o th s la id m o r e e g g s if t h e i r

p r e im a g in a l life h a d b e e n u n d e r h ig h e r h u m id itie s .
T h e p r e s e n t d is tr ib u tio n of th e o r i e n t a l f r u i t m o th in
t e m p e r a t e r e g io n s a p p e a r s to be g o v e rn e d by r e la tiv e h u m id ity .

v ii
G H U L A M -U L L A H CHAUDHRY

A B ST R A C T

In h u m id a r e a s th e i n s e c t is m o r e a b u n d a n t th a n in d r y a r e a s .
T h is d if f e r e n c e i s e x p la in e d h e r e b y th e in flu e n c e of r e la tiv e
h u m id ity on i t s d e v e lo p m e n t a n d on th e s u c c e s s f u l c o m p le tio n
of l a r v a l d ia p a u s e ; h ig h e r h u m id itie s f a v o u rin g th is in s e c t a n d
lo w e r h u m id itie s a ffe c tin g i t s b io tic p o te n tia l a d v e r s e ly .

T A B L E O F C O N TEN TS

Page
I.

I N T R O D U C T I O N ..........................................................

1

II.

T E C H N IQ U E AND M E T H O D S ................................

6

III.

N O M E N C L A T U R E AND D E S C R IP T IO N
O F S P E C I E S ...............................................................

IV.

10

D E V E L O P M E N T AND V IA B ILIT Y O F
G R A PH O L IT H A M O L E S T A ................................
•»>

17

1.

18

E g g S t a g e ...........................................................
(a)

E f fe c t of t e m p e r a t u r e on
d e v e l o p m e n t .............................................
(i)

In c u b a tio n p e r i o d ................................

(ii) T h r e s h o ld of d e v e lo p m e n t

. . .

(iii) U p p e r v i ta l l i m i t ................................
(b)

2.

1820 .
26

E f f e c t of h u m id ity on d e v e lo p m e n t
of e g g s ..........................................................

(c)

18

29

E f f e c t of te m p e r a t u r e an d
h u m id ity on v i a b i l i t y ..........................

30

L a r v a l S t a g e ....................................................

35

ix
Page
(a)

E f fe c t of t e m p e r a t u r e on
d e v e l o p m e n t .............................................
(i)

D u r a t i o n .................................

(ii)

T h r e s h o ld of d e v e lo p m e n t

(b)

35
. . .

41

E f fe c t of t e m p e r a t u r e on
v ia b ility

3.

35

...................................................

P u p a l S t a g e ........................................
(a)

42
43

E f fe c t of t e m p e r a t u r e on

(i)

d e v e l o p m e n t ...........................

45

D u r a t i o n ...................................

45

(ii) T h r e s h o ld of d e v e lo p m e n t

. . .

55

(iii) O p tim u m a n d u p p e r v ita l
l i m i t s ..................................
(b)

E f fe c t of h u m id ity on
d e v e l o p m e n t .............................

(c)

4.

56

57

E ffe c t of t e m p e r a t u r e a n d
h u m id ity on v i a b i l i t y ........

59

L a r v a l D i a p a u s e ............................

61

(a)

S h o rt D ia p a u s e
(i)

......................................

E f fe c t of t e m p e r a t u r e . . . .

65
65

X

Page
(ii) E ffe c t of h u m i d i t y ..........................

66

L ong D i a p a u s e .............................................

68

(b)

(i)

E ffe c t of t e m p e r a t u r e

.

.

.

.

(ii) E f f e c t of h u m i d i t y ..........................
5.

73

E m e r g e n c e of M o th s U n d e r
D if fe r e n t C o n d i t i o n s ................................

74

(i)

75

E f fe c t of t e m p e r a t u r e

. . . . .

(ii) E ffe c t of h u m i d i t y ..........................
V.

69

76

T H E FE C U N D IT Y O F G R A PH O L IT H A
M O L E ST A U N D ER D IF F E R E N T
C O N D I T I O N S ................................................................
(i)

E ffe c t of t e m p e r a t u r e

. .

.

.

(ii) E ffe c t of h u m i d i t y ..........................

80
83
85

(iii) E x p e r im e n ts a t ro o m
t e m p e r a t u r e .......................................
V I.

85

M E T E O R O L O G IC A L D A TA AND
IN C ID EN C E O F T H E O R IE N T A L
F R U IT M O TH

..........................................................

89

V II.

SUMM ARY AND C O N C L U S IO N S ...........................

129

V III.

L IT E R A T U R E C I T E D ..............................................

137

I.

IN TRO D U CTIO N

The o r i e n t a l f r u i t m o th , G ra p h o lith a (C ydia) m o le s ta
(B u sc k ) is a n im p o r ta n t in s e c t p e s t of p e a c h a n d o th e r sto n e
f r u i t s , a p p le , q u in c e a n d p e a r .

T he l a r v a e b o re in to te n d e r

s h o o ts of p e a c h , w h ic h is th e m a jo r h o s t p la n t in th e U n ited
S ta te s of A m e r ic a , a n d l a t e r th e y a tta c k i t s f r u i t s .
c a s e of o th e r h o s ts th e p e s t g e n e r a lly a tta c k s f r u i t s .

In th e
The

m o th w a s r e p o r te d f i r s t in 1916 doing c o n s id e r a b le d a m a g e
to p e a c h t r e e s w ith in a r a d iu s of tw e n ty m i l e s a ro u n d W ash ­
in g to n , D. C.

S u b s e q u e n t in v e s tig a tio n s sh o w ed th a t it w a s

in tr o d u c e d in to th a t lo c a lity on flo w e rin g c h e r r i e s im p o rte d
fro m Jap an about th re e y e a rs e a r lie r .

B y 1918 th e p e s t h a d

s p r e a d to N ew J e r s e y , N ew Y o rk an d C o n n e c tic u t; e v e r sin c e
it h a s b een s p r e a d in g to d e c id u o u s o r c h a r d s in a l l d ir e c tio n s ,
In s p ite of s t r i c t q u a ra n tin e m e a s u r e s th e p e s t is now w e ll
e s ta b lis h e d in C a lif o r n ia .
O u tsid e th e U n ite d S ta te s of A m e r ic a th e o r ie n ta l f r u i t
m o th h a s b e e n r e c o r d e d f r o m C a n a d a , Ita ly , F r a n c e , N ew Z e a l­
and, A u s tra lia ,

C h in a a n d J a p a n .

In J a p a n i ts d a m a g e w as

f i r s t n o tic e d in O k a y a m a P r e f e c t u r e in 1901 a n d 1902, a s

r e p o r t e d by H a ru k a w a (12) a n d H a e u s s l e r (14).

It i s now g e n ­

e r a l l y d i s t r ib u t e d th ro u g h o u t th e c e n t r a l a n d s o u th e r n p a r t s of
Jap an .

B oth f r u i t s a n d tw ig s of p e a c h , s a n d p e a r , p e a r , q u in c e ,

a p p le , a p r i c o t, b la c k p lu m , C h in e s m a l u s , a n d o n ly th e tw ig s of
c h e r r y , J a p a n e s e flo w e rin g c h e r r y ( P y r u s t r i f l o r a ) , s a n d c h e r r y ,
J a p a n e s e a p r i c o t ( P r u n u s um e) a n d p lu m a r e a tta c k e d .

hi Jap an

it is of p r i m a r y im p o r ta n c e a s a p e s t of s a n d p e a r w h ich is of
m o r e im p o r ta n c e a s a f r u i t c ro p th a n is th e p e a c h .
So f a r th e o r i e n t a l f r u i t m o th i s n o t r e p o r te d f r o m P a k ­
is ta n a n d In d ia , a lth o u g h tw o c lo s e ly r e l a t e d s p e c ie s , th e c o d lin g
m o th , C a r p o c a p s a (C y d ia) p o m o n e lla (L inn) a n d th e p e a c h tw ig
b o r e r , A n a r s ia lin e a t e l l a Z e ll, a r e s e r i o u s p e s t s in th e t e m ­
p e r a t e f r u i t g ro w in g a r e a s of th e s e c o u n tr i e s .

It w ould b e

i n te r e s ti n g to fin d o u t so m e of th e f a c t o r s w h ic h m a y h a v e p r e ­
v e n te d th e s p r e a d of G ra p h o lith a m o le s ta to th is a r e a .

It is

j u s t p o s s ib le th a t th e m o th d id n o t g a in a c c e s s to th is re g io n .
It is m o r e lik e ly th a t c lim a tic c o n d itio n s w e r e n o t q u ite s u ita b le
f o r i t s d e v e lo p m e n t.

A n a n a ly s is of th e s e f a c t o r s m a y b rin g

o u t s o m e lim ita tio n s r e s p o n s ib le f o r i t s a b s e n c e in th o s e r e g io n s .
T h e b io lo g y a n d c o n tr o l of th e f r u i t m o th h a s b e e n s tu d ­
ie d e x te n s iv e ly a t d if f e r e n t a g r i c u l t u r a l e x p e r im e n t s ta tio n s in

3
th e U n ite d S ta te s of A m e r ic a , C a n a d a a n d J a p a n .

In a lm o s t a ll

th e s e in v e s tig a tio n s , th e in s e c t s w e re s tu d ie d e it h e r in th e fie ld
o r u n d e r u n c o n tro lle d c o n d itio n s in th e l a b o r a to r y .

H ence, it

is n o t p o s s ib le to e v a lu a te th e e ff e c t of v a r io u s e n v iro n m e n ta l
f a c t o r s on th is p e s t.

C o m p a r a tiv e ly l i t t l e is know n a b o u t the

p o te n tia litie s of th is in s e c t, th e r a t e of i t s d e v e lo p m e n t, u p p e r
v ita l l im i t s f o r th e v a r io u s s ta g e s , th e v ia b ility of i ts p r e im a g in a l s ta g e s a n d th e fe c u n d ity a n d lo n g e v ity of a d u lts u n d e r
d if f e r e n t c o n tr o lle d c o n d itio n s .

T he te n d e n c y of m o d e r n e c o l­

o g is ts h a s b e e n to stu d y in s e c ts o n ly in th e fie ld .

A c c u r a te

a n a ly s is of o b s e r v a tio n s in th e f ie ld is v e r y d iffic u lt.

hi sp ite

of th e f a c t th a t v a ry in g t e m p e r a t u r e s in n a tu r e a r e m o r e im ­
p o r ta n t f r o m a n e c o lo g ic a l p o in t of v ie w , th e r e s e a r c h p ro b le m
m u s t p a s s th ro u g h th e la b o r io u s s ta g e s of in v e s tig a tio n u n d e r
c o n s ta n t t e m p e r a t u r e s in o r d e r to la y a fo u n d a tio n f o r t h e i r
p r o p e r u n d e rs ta n d in g .

L a b o r a to r y a n d f ie ld e c o lo g y a r e i n t e r ­

d e p e n d e n t a n d b o th a r e e s s e n t i a l .

B y c o r r e l a t in g th e r e s u l t s

of s tu d y in th e l a b o r a to r y w ith th o s e in th e f ie ld i t is s o m e ­
t im e s p o s s ib le to so lv e p r o b le m s of i n s e c t a b u n d a n c e .

U v a ro v

(Z9) e m p h a s iz e d th e im p o rta n c e of p r o p e r l y p la n n e d s tu d ie s in
th e la b o r a to r y so a s to u tiliz e th e r e s u l t s in u n d e rs ta n d in g the
p r o b le m s in n a tu r e .

4
C o n tro l of th e o r i e n t a l f r u i t m o th h a s d e p e n d e d to a
la r g e e x te n t in th e p a s t on u s e f u l p a r a s i t e s .

In o r d e r to a s s e s s

p r o p e r l y th e p o te n tia litie s of a p e s t a n d i ts p a r a s i t e s , a k n o w l­
ed g e of t h e i r b e h a v io r u n d e r d if f e r e n t c o n tr o lle d c o n d itio n s of
e n v iro n m e n t is of fu n d a m e n ta l im p o r ta n c e .

T h e s e s tu d ie s r e ­

v e a l th e c o n d itio n s u n d e r w h ich th e p e s t a n d th e p a r a s i t e s
f l o u r is h a n d m u ltip ly b e s t.
T e m p e r a tu r e is th e g r e a t e s t s in g le f a c t o r w h ich a ffe c ts
th e g e o g ra p h ic d is tr ib u tio n of a n y s p e c ie s of in s e c ts on th is
e a r th .

T h e b io tic p o te n tia l, i ts b e h a v io r , f o r m a n d s t r u c t u r e ,

a l l a r e in flu e n c e d by th is e n v ir o n m e n ta l f a c t o r .

A p a rt fro m

i ts d i r e c t e f f e c ts , t e m p e r a t u r e in flu e n c e s o th e r f a c t o r s , s u c h a s
lig h t, m o i s t u r e , m o v e m e n t of a i r , e tc .

T h e d is tr ib u tio n of

a n im a ls in m a n y p a r t s of th e w o rld is m o r e o r l e s s c lo s e ly
tie d up w ith t e m p e r a t u r e .

A n o th e r f a c to r w h ic h c o n tr o ls the

g e o g ra p h ic ra n g e of a n o r g a n is m is m o is tu r e .
W ith th e s e p o in ts in v ie w in v e s tig a tio n s on th e e co lo g y
of th e o r i e n t a l f r u i t m o th w e r e s t a r t e d in 1950 a t E a s t L a n s in g ,
M ic h ig a n , by r e a r i n g th e i n s e c t u n d e r c o n s ta n t te m p e r a t u r e s
a n d r e l a ti v e h u m id itie s .

A p a r t f r o m th is , m e te o r o lo g ic a l d a ta

f r o m t h r e e ty p ic a l s ta tio n s in U. S. A . h a v e b e e n c o m p a re d

w ith th o s e of t h r e e ty p ic a l p e a c h a n d a p p le g ro w in g a r e a s in
P a k is ta n , in o r d e r to e x p lo re th e p o s s ib i l i ti e s f o r th e e s t a b l is h ­
m e n t of th e o r i e n t a l f r u i t m o th in th e l a t t e r c o u n try .

II.

T EC H N IQ U E AND M ETHODS

C o lle c tio n

A b o u t a d o z e n h ib e rn a tin g la r v a e of th e o r i e n t a l f r u i t
m o th w e r e r e c e iv e d f r o m B e n to n H a r b o r , M ic h ig a n , in the w in­
t e r of 1950.

D u rin g M ay, 1950, s e v e r a l v i s i t s w e re m a d e to

th a t a r e a , w h e re q u in c e a n d p e a c h tr u n k s w e re e x a m in e d f o r
h ib e r n a tin g la r v a e a n d p u p a e .

T h e s e a tte m p ts d id n o t p ro v e

a s u s e f u l a s a n tic ip a te d , b e c a u s e e a c h tim e v e r y few s p e c im e n s
c o u ld be c o lle c te d .

In a ll a b o u t tw o d o z en m o th s e m e rg e d .

T h e y d ie d a f t e r la y in g o n ly fiv e e g g s .
On a c c o u n t of e x te n d e d c o ld w e a th e r th e p e s t did n o t
m a k e i ts p r e s e n c e n o tic e a b le in th e L a n s in g a r e a t i l l ab o u t th e
en d of J u n e , 1950.

P e a c h o r c h a r d s a ro u n d L a n s in g , M a so n an d

G ra n d R a p id s w e re e x a m in e d fre q u e n tly d u rin g Ju n e to S e p te m ­
b e r , 1950.
th a n 0 .1 % .

T h e in f e s ta tio n in tw ig s of p e a c h w a s n e v e r m o re
On so m e in d iv id u a l t r e e s it w ould ra n g e f r o m 2 -5

in f e s te d s h o o ts .

W ilte d s h o o ts w ith th e l a r v a e b o rin g in sid e

w e r e c u t a n d b ro u g h t to th e la b o r a to r y .

7
R e a rin g

T he c u t s h o o ts w e re k e p t sta n d in g in m o is t s a n d a n d th is
g e n e r a lly a llo w e d th e l a r v a e to b e c o m e fu ll g ro w n a n d c o m e ou t
f o r p u p a tio n in c o r r u g a te d p a p e r s h e e ts p ro v id e d f o r th is p u r ­
pose.

T h e p u p a e w e r e k e p t a t ro o m te m p e r a tu r e (70 - 8 0° F . ) .

T h e m o th s e m e r g in g f r o m th is m a t e r i a l w e re l ib e r a te d f o r o v ip o s itio n in c a g e s of 10" x 10" x 8 " s i z e , m a d e of w ooden
fra m e s.

T he s id e s a n d to p of th is ty p e of c ag e w e re c o v e r e d

w ith th in m u s lin , w h ic h w a s a p p lie d f r o m in s id e .

T he cage

w a s k e p t a t ro o m te m p e r a t u r e o v e r m o is t s a n d in a la r g e
en am el tra y .

A w ad of c o tto n w ool s o a k e d in th in s u g a r s o lu ­

tio n w a s k e p t in e a c h c a g e f o r th e m o th s to fe e d upon.

F re sh

p e a c h s h o o ts in s m a ll b o ttle s a n d tu b e s f ille d w ith w a te r w e re
k e p t in c a g e s f o r th e m o th s to la y e g g s upon.

T h e b o ttle s a n d

tu b e s w e r e w ra p p e d w ith c lo th to p r e v e n t th e m o th s f r o m l a y in g e g g s on th e g l a s s .
T he s h o o ts w ith e g g s on th e m w e re re m o v e d f r o m th e
c a g e s e v e r y m o rn in g .

A few h o u r s b e fo re th e h a tc h in g of th e

l a r v a e th e s h o o ts w e r e k e p t o v e r p a r t l y s lic e d a p p le s in g la s s
d is h e s a n d b e a k e r s .

T h e d is h w a s th e n k e p t a t th e te m p e r a tu r e

a t w h ic h th e la r v a e w e re to b e r e a r e d .

T he la r v a e e n te r e d the

a p p le s so o n a f t e r h a tc h in g .

G e n e r a lly th e y w ould le a v e th e

f r u i t o n ly a f t e r th e y w e re f u ll g ro w n a n d re a d y to s p in c o c o o n s.
T he e n ti r e r e a r i n g in th e la b o r a to r y w a s done on J o n a th a n a p ­
p le s re m o v e d f r o m th e t r e e s in A u g u s t a n d s to r e d a t 5 0 ° F .
A know n n u m b e r of f u ll g ro w n l a r v a e w e re th e n t r a n s f e r r e d
to c o r r u g a te d p a p e r s t r i p s k e p t in s m a ll g la s s v i a l s , f o r s p in ­
n in g c o c o o n s a n d p u p a tio n .

T he m o u th of e a c h v ia l w a s c o v e re d

w ith c lo th to p r e v e n t th e l a r v a e f r o m e s c a p in g .

T h ey w e re th e n

k e p t a t th e r e q u i r e d te m p e r a t u r e a n d h u m id ity .
T he m o th s e m e r g in g f r o m th e v ia ls w e re r e l e a s e d in
c a g e s f o r o v ip o s itio n .

A s th e s e c a g e s w e re to be k e p t in in c u ­

b a to r s th e y w e r e s m a l l e r th a n th o s e k e p t f o r g e n e r a l r e a r in g
a t ro o m t e m p e r a t u r e .

T h e y c o n s is te d of 6" d ia m e te r w ire

lo o p s s u p p o rte d by 8 " long p ie c e s of w ir e .
c o v e r e d w ith th in m u s lin .
g la s s d is h e s .
in c o tto n w o o l.

S id e s a n d to p w e re

T h ey w e re k e p t on m o is t s a n d in

T he m o th s w e re fe d on s u g a r s o lu tio n s o a k e d
T he e g g s la id by m o th s on g r e e n p e a c h sh o o ts

w e re c o u n te d d a ily a n d th e sh o o ts c h a n g e d .

A r e g u l a r su p p ly

of g r e e n p e a c h s h o o ts w a s m a in ta in e d by r a is in g s e e d lin g s in
th e g r e e n h o u s e .

T e m p e r a tu r e C o n tro l

F o r 60

a n d 65

F . a r e f r i g e r a t in g c a b in e t f itte d w ith

a s p e c ia l e l e c t r i c th e r m o s t a t i c c o n tr o l w a s u s e d .

F o r h ig h e r

t e m p e r a t u r e s e l e c t r i c in c u b a to r s , w ith a c c u r a te t h e r m o s ta tic
c o n tr o ls w e re e m p lo y e d .

A th e r m o g r a p h w a s k e p t in e a c h of

th e m to r e c o r d t e m p e r a t u r e .
n o t m o r e th a n 0 .5

o

F lu c tu a tio n of t e m p e r a tu r e w as

F.

H u m id ity C o n tro l

C o n s ta n t h u m id itie s in c lo s e d s p a c e , c a n be o b ta in e d by
u sin g s u lp h u ric a c id s o lu tio n s o r s u p e r s a t u r a t e d s a l t s o lu tio n s .
In th e s e e x p e r im e n ts s a l t s o lu tio n s w e r e u s e d .

T h is m e th o d

h a s a n a d v a n ta g e in th a t a s ta n d a r d s o lu tio n is m a in ta in e d
w h ich g iv e s c o n s ta n t h u m id ity .

It d o e s n o t r e q u i r e fr e q u e n t

c h a n g in g a n d d o e s n o t s p o il e a s ily .

C h e m ic a lly p u re s a l ts

a p p r o p r ia te f o r e a c h r e la tiv e h u m d ity a t d if f e r e n t t e m p e r a t u r e s
w e r e u s e d (16).

T h e y w e re p la c e d a t th e b o tto m of d e s i c c a t o r s

a n d j u s t enough d i s t il l e d w a te r w a s a d d e d a s to c o v e r th e s u r -

III.

N O M E N C L A T U R E AND D E S C R IP T IO N O F S P E C IE S

T he o r i e n t a l f r u i t m o th w a s d e s c r ib e d by A u g u st B u sc k
of th e U. S. B u r e a u of E n to m o lo g y a s L a s p e y r e s i a m o l e s t a .
T h e d e s c r ip tio n w as p u b lis h e d b y Q u in ta n c e a n d W ood in 1916
(21).

P r i o r to th e abov e F r o g a t t m e n tio n e d th is in s e c t a s a n

u n id e n tifie d e n e m y of p e a c h in A u s tr a l ia u n d e r th e p o p u la r
n a m e , p e a c h tip m o th (8).

E n q u ir ie s m a d e by H a e u s s le r (14)

in J a p a n r e v e a le d th a t th is in s e c t w a s know n in J a p a n in 1901
an d 1902, e s p e c ia lly a s a p e s t of s a n d p e a r .
H e in ric h (15) p la c e d th is m o th in th e g e n u s G ra p h o lith a
T r e i ts c h k e , f a m ily O le th r e u tid a e .
T he p e s t h a s b e e n know n u n d e r s e v e r a l co m m o n n a m e s
in th e p a s t , e . g . , p e a c h tip m o th , s m a l l e r p e a r b o r e r , o r ie n ta l
p e a c h w o rm , o r i e n t a l p e a c h m o th a n d o r i e n t a l f r u i t m o th .

T he

l a s t n a m e w a s m o s t w id e ly u s e d in A m e r ic a n l i t e r a t u r e an d
w a s , t h e r e f o r e , a d o p te d by th e A m e r ic a n A s s o c ia tio n of E c o ­
n o m ic E n to m o lo g is ts a s th e a p p ro v e d n a m e .
T he E u ro p e a n w r i t e r s , p a r t i c u l a r l y th e e n to m o lo g is ts in
E n g la n d , p la c e th is s p e c ie s in th e g e n u s C y d ia H u b n e r a s su g ­
g e s te d b y W a lsin g h a m a n d D u r r a n t in B io lo g ia .

T h ey s u b s titu te d

C y d ia H . f o r C a r p o c a p s a T r ie ts c h k e a n d d e s ig n a te d L a s p e y r e s i a
H u b n e r a s a sy n o n y m .

T h e R e v ie w of A p p lie d E n to m o lo g y p u b ­

lis h e d f r o m L o n d o n c o n tin u e s to r e f e r th e o r ie n ta l f r u i t m o th
u n d e r th e g e n u s C y d ia H .
F o llo w in g is th e o r ig in a l d e s c r ip tio n p r e p a r e d by B u sc k :
L a s p e y r e s i a m o le s t a , n .

sp .

H e a d d a r k , sm o k y fu s c o u s ; fa c e a sh a d e d a r k e r , n e a r ly
b la c k ; la b ia l p a lp i a sh a d e lig h te r fu s c o u s ; a n te n n a e s im p le ,
r a t h e r s to u t, h a lf a s long a s .the f o r e w in g s, d a r k fu s c o u s
w ith th in , in d is tin c t, w h itis h a n n u la tio n s .
T h o ra x b la c k is h
f u s c o u s ; p a ta g ia f a in tly i r r o r a t e d w ith w h ite , e a c h s c a le
b e in g s lig h tly w h ite -tip p e d .
F o re w in g s n o r m a l in f o r m ;
t e r m e n w ith s lig h t s in u a tio n b elo w a p e x ; d a r k f u s c o u s , o b ­
s c u r e l y i r r o r a t e d by w h ite -tip p e d s c a l e s ; c o s ta l edge
b la c k is h , s t r i g u la t e d w ith o b s c u r e , g e m in a te , w h ite d a s h e s ,
f o u r v e r y f a in t p a i r s on b a s a l h a lf a n d th r e e m o r e d is tin c t
on o u te r h a lf b e s id e s tw o s in g le w h ite d a s h e s b e fo re a p ex ;
f r o m th e b la c k c o s ta l i n te r v a l s ru n v e r y o b s c u r e , w avy,
d a r k lin e s a c r o s s th e w in g , a l l w ith a s tr o n g o u tw a rd ly
d i r e c te d w ave on th e m id d le of th e w ing; on th e m id d le of
th e d o r s a l ed g e th e s p a c e s b e tw e e n t h r e e of th e s e lin e s
a r e m o r e s tr o n g ly i r r o r a t e d w ith w h ite th a n is th e r e s t
of th e w ing, so a s to c o n s titu te tw o f a in t a n d p o o rly d e ­
f in e d w h ite d o r s a l s t r e a k s .
A ll th e s e m a r k in g s a r e o n ly
d is c e r n ib le in p e r f e c t s p e c im e n s a n d u n d e r a le n s ; o c e llu s
s tr o n g ly i r r o r a t e d w ith w h ite , e d g e d by tw o b ro a d p e rp e n ­
d ic u la r , f a in t b lu is h m e t a l l ic lin e s a n d c o n ta in in g s e v e r a l
s m a ll d e e p b la c k , i r r e g u l a r d a s h e s , of w h ich th e fo u rth
f r o m to r n u s is th e lo n g e s t a n d p la c e d f a r t h e r o u tw a rd , so
a s to b r e a k th e o u te r m e ta llic edge of o c e llu s ; th e lin e of
b la c k d a s h e s a s w e ll a s th e a d jo in in g b lu is h m e ta llic lin e s
a r e c o n tin u e d f a in tly ab o v e th e o c e llu s in a c u rv e to th e
l a s t g e m in a te c o s ta l s p o ts ; t h e r e is a n in d is tin c t, b la c k
a p ic a l s p o t a n d tw o o r th r e e s m a ll b la c k d o ts b elo w it; a
th in b u t d is tin c t, d e e p b la c k , t e r m in a l lin e b e fo re th e c ilia ,

12
c ilia d a r k b ro n z y £ u sc o u s.
H ind w in g s d a r k b ro w n w ith
c o s ta l :d g e b ro a d ly w h ite; c ilia w h itis h , u n d e rs id e of w ings
lig h te r fu s c o u s w ith s tr o n g i r r i d e s c e n t sh e e n ; a b d o m e n d a rk
fu s c o u s w ith s i l v e r y w h ite u n d e rs id e ; le g s d a rk fu s c o u s w ith
in n e r s id e s s i l v e r y , t a r s i b la c k is h w ith n a rr o w , y e llo w ish
w h ite a e m u latio n s.
A l a r e x p a n se ; 10-15 m m .
U n ite d S ta te s N a tio n a l M u s e u m ty p e 20664.
T he fe m a le g e n ita lia c o n s is t of two c lo s e ly a p p ro x im a te d ,
s e to s e e g g - g u id es, lik e e lo n g a te p h y llo c la d e s of O p u n tia sp .
Som e s e ta e on the o u te r m a r g in s of e g g -g u id e s a r e lo n g e r th a n
th e r e s t .

L a r g e s c a l e s c a u d a d of th e l a s t a b d o m in a l se g m e n t

f o r m a f a n - s h a p e d s t r u c t u r e c o v e rin g th e e g g -g u id e s f r o m th e
d o r s a l s id e .

In th e m a le th e tw o g r a y , a c u m in a te c la s p e r s

f o r m a d a rk s l i t b e tw e e n th e m on a c c o u n t of th e p r e s e n c e of
a l a r g e n u m b e r of b la c k s e ta e on th e m e s a l s u r f a c e s .

D e s c r ip tio n of S ta g e s

The E g g ;

T he egg is w h itis h , s c a l e - li k e s e m itr a n s p a r e n t, c i r ­

c u la r to o v a l in o u tlin e , f la t, u p p e r s u r f a c e s lig h tly ru g o s e a n d
co n v ex , d ia m e te r 0. 65 m m . to 0. 75 m m .

T he eg g s a r e g e n ­

e r a l l y la id c n th e u p p e r s u r f a c e of p e a c h le a v e s .

H o w ev e r, in

th e la b o r a to ■y th e y a r e la id on b o th s id e s of th e le a f a s w ell
a s on th e sh o o t.

B e fo re h a tc h in g th e b la c k h e a d of th e la r v a

is c o n sp ic u o u sly v is ib le th ro u g h th e e g g -s h e ll.

T he L a r v a ;

T he la r v a r e s e m b l e s th a t of th e c o d lin g m o th in

s e v e r a l r e s p e c t s b u t is s m a l l e r in s iz e .

T he young l a r v a is

d i r ty c r e a m in c o lo u r, b e c o m e s p in k w hen a lm o s t fu ll g ro w n .
T he fo llo w in g is e s s e n t ia ll y th e d e s c r ip tio n g iv e n by G a rm a n
(9):

H e a d c a p s u le b la c k a n d sh in in g , s o m e tim e s p ro v id e d w ith

p a le m a r k in g s ; body p in k is h w h ite , th e p r o th o r a c ic a n d a n a l
s h ie ld s u s u a lly b ro w n ; le n g th of fu ll-g ro w n l a r v a 12-15 m m .
L e n g th of la b iu m one a n d o n e -h a lf tim e its w id th , c a rd o
a s long a s th e s tip e s ; m e n tu m e x p a n d e d a t th e c a u d a l e x tr e m ­
ity a n d w ith tw o h e a v y s e ta e n e a r the m id d le ; m a x i l la r y p a lp i
t h r e e s e g m e n te d , th e b a s a l s e g m e n t w ith a long s e ta on th e
in n e r s u r f a c e ; g a le a - la c in ia w ith fo u r d is tin c t te e th , two of w h ich
a r e c h itin iz e d , th e tip s of th e c h itin iz e d p r o je c tio n s w ith b lu n t
t u b e r c le s , la b ia l p a lp i s le n d e r , c o m p o s e d of two s e g m e n ts , a
v e r y s h o r t g lo b u la r, d i s t a l s e g m e n t tip p e d w ith a long s e ta a n d
a long p r o x im a l s e g m e n t w ith a s h o r t s e ta a t th e a p e x ; tip of
th e la b iu m h e a v ily c h itin iz e d ; a n te n n a e f o u r - s e g m e n te d , th e
t h ir d s e g m e n t w ith a long s e ta n e a r th e d i s t a l e n d , th e d is ta l
s e g m e n t a b o u t o n e -h a lf th e d ia m e te r o f th e p re c e d in g s e g m e n t,
a n d p ro v id e d w ith a b lu n t p r o je c tio n a n d a long s e ta ; th ir d
s e g m e n t w ith tw o s h o r t s e t a e , one long s e ta a n d a b lu n t p r o ­
je c tio n s i m i l a r to th a t of th e d i s t a l s e g m e n t.

T h o ra x a n d a b d o m e n :

S e g m e n t nin e of th e a b d o m e n w ith

a lp h a s o m e tim e s r e p r e s e n te d by a tu b e r c le o r s h o r t s e ta n e a r
th e d o r s o —m e s o n d e lta (II) lo c a te d on th e s a m e p in n a c u lu m w ith
rh o (III); k a p p a (IV) a n d m u (V) on th e s a m e p in n a c u lu m a n d
a b o u t e q u id is ta n t; k a p p a ( p r e s p ir a c u l a r ) g ro u p of th e p r o th o r a x
w ith th e m id d le s e ta lo n g e s t a n d e q u id is ta n t f r o m th e re m a in in g
tw o; k a p p a g ro u p (V a n d VI) b is e to s e on s e g m e n ts one to e ig h t,
p i (VII) g ro u p u n is ito s e on s e g m e n ts s e v e n , e ig h t a n d n in e .
C r o c h e ts u n io rd in a l; d e n s e ly p la c e d in a c o m p le te c i r c le ; th e
l a t e r a l h o o k s s o m e tim e s s h o r t, n u m b e r of c r o c h e ts on p r o le g s
3 to 6 v a ry in g f r o m 30 to 46, h o o k s of i r r e g u l a r le n g th i n f r e ­
q u e n t.

C r o c h e ts of th e a n a l p r o le g s in fu ll g ro w n la r v a e 19 to

22, th e c u tic le im m e d ia te ly c e p h a lid w ith o u t th ic k s e t p ad of
s p in e s , a n a l f o r k w ith 5 -7 s p in e s u s u a lly of e q u a l le n g th an d
p a r a l l e l , th e tw o m e s a l s p in e s s o m e tim e s b lu n t.
T he fu ll g ro w n l a r v a of th e o r i e n t a l f r u i t m o th c an be
d is tin g u is h e d f r o m th a t of th e c lo s e ly r e l a te d s p e c ie s co d lin g
m o th ,

C a r p o c a p s a p o m o n e lla ( L in n .) , a n d th e p e a c h tw ig b o r e r ,

A n a r s i a lin e a te lla Z e ll, by th e fo llo w in g c h a r a c t e r s :

15

C h a r a c te r

O r ie n ta l
f r u i t m o th

C odling
m o th

Peach
tw ig b o r e r

1.

H a b its
of la r v a
and host
p la n ts

B o r e s in to the
tw ig s of p e a c h ,
n e c ta rin e , a p ­
ric o t and f ru its
of q u in c e ,
p e a c h , a p p le
a n d p lu m .

B o r e s in to
f r u i t s of
a p p le , p e a r
a n d q u in c e .

B o r e s into
tw ig s of p e a c h ,
p lu m , a p r ic o t
a n d a lm o n d .
L a t e r in s e a s o n
f r u i t s of th e s e
tre e s .

2.

C o lo r

P in k , u s u a lly
p in k is h .

D ir ty w hite
o r p in k .

L ig h t to re d d is h
b ro w n .

3.

L e n g th

10-12 m m .

1 4 -1 6 m m .

10-11 m m .

4.

W idth

3 -4 m m .

4 -5 m m .

3 -4 m m .

5.

P in a c u la e
a ro u n d
p rim a ry
s e ta e

In c o n s p ic u o u s.

In c o n s p ic ­
u o u s.

D is tin c tly p ig ­
m e n te d .

6.

C r o c h e ts

F o rm a com ­
p le te c i r c l e .

F o rm a
c o m p le te
c irc le .

B ro k e n into
tw o g ro u p s .

7.

A nal
fo rk

P r e s e n t w ith
4 -7 a lm o s t
p a r a l l e l p ro n g s .

A b s e n t.

P r e s e n t w ith
g e n e r a lly 6
p r o n g s , m o re
o r l e s s d iv e r ­
g e n t.

T he P upa:

T he l a r v a e in s u m m e r s p in th in s ilk e n c o c o o n s,

w h e r e a s th o s e o v e rw in te rin g m a k e th ic k c o c o o n s.

T h e f r e s h ly

16
f o r m e d p u p a , 4 .5 to 5 .5 m m . in le n g th (in sid e th e cocoon) is
u n if o r m ly b ro w n .

It g r a d u a lly tu r n s d a rk r e d .

O ne to two

d a y s b e fo r e th e e m e rg e n c e of th e a d u lt th e w ing p a d s tu r n
b la c k .

T h e a b d o m e n is c o m p o s e d of te n s e g m e n ts .

T he l a s t

t h r e e a p p a r e n tly f u s e d to g e th e r ; th e c e p h a lic m a r g in s of s e g ­
m e n ts 2 to 9 w ith a ro w of h e a v y s e ta e , th e c a u d a l m a r g in s
of s e g m e n ts 2 to 7 w ith ro w s of m u c h f i n e r s e ta e , th e c a u d a l
m a r g in of th e te n th s e g m e n t w ith s ix h e a v y s p in e s b e tw e e n w hich
a r e s o m e w h a t lo n g e r h o o k e d s e ta e ; a n d w ith tw o s h o r t s e ta e
p r e s e n t on e a c h sid e of th e a n a l r i s e .

IV.

D E V E L O P M E N T AND V IA B ILIT Y O F
G R A PH O L IT H A M O LESTA

F o llo w in g i t s d is c o v e r y in th e D i s t r i c t of C o lu m b ia in
1916 th e o r i e n t a l f r u i t m o th , G ra p h o lith a m o le s ta w a s s tu d ie d
e x te n s iv e ly a t s e v e r a l a g r i c u l t u r a l e x p e r im e n t s ta tio n s .in the
U. S. A .

T he f i r s t r e p o r t on i ts life h i s t o r y w a s p u b lis h e d

b y G a r m a n (9) in 1917 fo llo w e d by th a t of W ood a n d S e lk re g g
(30).

S te a r n s (26) c a r r i e d o u t e x te n s iv e s tu d ie s in a n open a i r

in s e c t a r y d u rin g 1919 a n d 1920 in N o r th e r n V irg in ia .

S te a r n s

a n d P e t e r s o n (27) s tu d ie d th e life a n d s e a s o n a l h i s t o r y in N ew
J e r s e y , Snapp a n d S w ingle (24) in G e o rg ia , G a rm a n (10) in
C o n n e c tic u t, S te a r n s a n d N e is w a n d e r (28) in O hio, E d d y a n d
N e ttle s (7) in S o u th C a ro lin a a n d A ld e n a n d C la rk e (2) in
G e o rg ia .

In a l l th e s e c a s e s th e in v e s tig a to r s s tu d ie d th e in ­

s e c t e i t h e r in th e o r c h a r d o r in th e in s e c t a r y a n d m a d e little
a tte m p t to c o r r e l a t e th e d e v e lo p m e n t of o r ie n ta l f r u i t m o th
w ith t e m p e r a t u r e a n d h u m id ity .
H a ru k a w a (13) in v e s tig a te d th e r e la tio n of te m p e r a tu r e
to th e g ro w th of th e m o th in J a p a n .

P e t e r s o n a n d H a e u s s le r

(20) a ls o s tu d ie d so m e a s p e c t s of th e life h is to r y of th is m o th

in r e l a ti o n to t e m p e r a t u r e , e it h e r p r e v a ilin g in th e o r c h a r d o r
in th e i n s e c t a r y .

T h e y a tte m p te d to c o r r e l a t e th e d e v e lo p m e n t

of th e v a r io u s b ro o d s w ith th e m e a n t e m p e r a t u r e s p re v a ilin g
in th e o r c h a r d a n d th e i n s e c t a r y .

S om e e x p e rim e n ts u n d e r

a lm o s t c o n s ta n t t e m p e r a t u r e s w e re c a r r i e d o u t by H a ru k a w a .
He p a id lit t le a tte n tio n to h u m id ity a s he b e lie v e d th a t r e la tiv e
h u m id ity d id n o t m u c h in flu e n c e th e r e s u l t s of h is e x p e r im e n ts .
D u s ta n (6) w o rk in g in th e N ia g a r a P e n in s u la of C a n ad a , m a d e
so m e o b s e r v a tio n s to fin d o u t th e e ffe c t of m e a n te m p e r a tu r e
a n d h u m id ity in th e i n s e c t a r y on th e d e v e lo p m e n t a n d fe c u n d ity
of o r i e n t a l f r u i t m o th .
D u rin g th e p r e s e n t in v e s tig a tio n th e d e v e lo p m e n t a n d
fe c u n d ity of th e o r i e n t a l f r u i t m o th w a s s tu d ie d in th e l a b o r a ­
t o r y u n d e r c o n s ta n t t e m p e r a t u r e a n d h u m id ity c o n d itio n s a n d
th e r e s u l t s a r e d e s c r ib e d b elo w .

1.

E gg S ta g e

(a) E f f e c t of t e m p e r a t u r e on d e v e lo p m e n t

(i) In c u b a tio n p e r i o d :

T he in c u b a tio n p e r io d of th e o r ie n ta l

f r u i t m o th h a s b e e n s tu d ie d by s e v e r a l w o r k e r s in th e p a s t.
U n d e r i n s e c t a r y c o n d itio n s S te a r n s (26) fo u n d i t to be 7 .3 9 d a y s

on a n a v e r a g e w ith a m in im u m of 4 d a y s a n d a m a x im u m of
10 d a y s f o r th e f i r s t b ro o d a s c o m p a r e d to a n a v e r a g e of 5. 59
d a y s , m in im u m of 3 d a y s a n d m a x im u m of 8 d a y s f o r th e f o u rth
b ro o d .

H is f ig u r e s f o r 1919 w e re q u ite d if f e r e n t f r o m th o se

f o r 1920.

S te a r n s a n d N e is w a n d e r (28) w o rk in g in O hio r e c o r d e d

a n in c u b a tio n p e r io d of 4 .4 , 4 .9 , 6 .0 5 , a n d 9 .4 d a y s f o r th e
se c o n d , th ir d , f o u r th a n d fifth b ro o d s r e s p e c tiv e ly w ith a m a x ­
im u m of 17 d a y s a n d a m in im u m of 3 d a y s.
H a ru k a w a (13) r e p o r t e d th a t u n d e r c o n s ta n t te m p e r a t u r e s
th e in c u b a tio n p e r io d w a s 3 .3 d a y s a t 32. 8 ° - 3 3 ° C . , 4 .1 d a y s
a t 3 2 . 2 ° - 3 2 .3 ° , 3 .2 d a y s a t 3 1 . 0 ° -3 1 . 3 ° , 3 .3 d a y s a t 2 8 . 3 ° 2 8 .5 ° , 4 .2 d a y s a t 24. 4 ° -2 4 . 6 ° , 6 .2 d a y s a t 2 0 .2 ° - 2 0 .5 ° a n d
1 2 ,9 d a y s a t 14. 9 ° C.

T h e re s e e m s to be so m e c o n tra d ic tio n

in th e s e o b s e r v a tio n s .

G a rm a n (10) gav e 12 to 15 d a y s a s th e

in c u b a tio n p e r io d a t a t e m p e r a t u r e of a b o u t 60° F .

P e te rs o n

an d H a e u s s l e r (20) w o rk in g a t R iv e rto n , N ew J e r s e y , c o r r e l a t e d
in c u b a tio n p e r io d w ith th e r i s e a n d f a ll of te m p e r a tu r e in t h e i r
o p en a i r i n s e c t a r y .

T h e y fo u n d it to v a r y f r o m 3 .5 to 6 d a y s

in s u m m e r , 7 -1 4 d a y s in e a r l y s p r in g a n d 20 d a y s o r lo n g e r
in la te f a l l .

T h e y fo u n d a m in im u m tim e of 6 0 -6 5 h o u r s u n d e r

m o r e o r l e s s c o n tr o lle d c o n d itio n s b u t th e y d id n o t m e n tio n the
te m p e ra tu re .

N one of th e s e w o r k e r s s tu d ie d th e e ff e c t of h u m id ity on
in c u b a tio n p e rio d .

T he r e s u l t s o b ta in e d u n d e r c o n s ta n t te m ­

p e r a t u r e s a n d h u m id itie s in th e p r e s e n t in v e s tig a tio n a r e g iv en
in T a b le I a n d sh o w n g r a p h ic a lly in F i g u r e s 1 to 3.

U n d e r 70%

r e l a ti v e h u m id ity i t w a s 7 .5 d a y s a t 6 0 °, 5 .7 5 d a y s a t 6 5 °, 3 .9
d a y s a t 7 5 °, 3 .2 7 d a y s a t 8 5 °, 2 .7 5 d a y s a t 9 4 ° a n d 3 .3 d a y s
a t 95

o

F.

T he in c u b a tio n p e r io d c o n tin u e d to d e c r e a s e w ith

th e r i s e of t e m p e r a t u r e u n til a m in im u m of 2 .7 5 d a y s w as
r e a c h e d a t 94

o

F . , t h e r e a f t e r i t a g a in s t a r t e d in c r e a s in g .

F ro m

th e s e d a ta i t is c l e a r th a t the e g g s of th is in s e c t co n tin u e to
d e v e lo p a t f a i r l y h ig h t e m p e r a t u r e s .

(ii) T h r e s h o ld of d e v e lo p m e n t:

T h e r e l a ti o n of in c u b a tio n p e rio d

to t e m p e r a t u r e is show n in F i g u r e s 1 to 3.

T he r e c i p r o c a ls

of th e p e r io d s m u ltip lie d by one h u n d re d a r e a ls o p lo tte d .

T he

t h e o r e ti c a l th r e s h o ld of d e v e lo p m e n t a s show n by th e i n t e r s e c ­
tio n of th e lin e s of in d ic e s of d e v e lo p m e n t a n d th e te m p e r a tu r e
a x e s (3, 18 a n d 22) in F i g u r e s 1 to 3, l.ies a t 4 0 ° to 4 4 ° F . ,
d e p e n d in g upon th e r e l a ti v e h u m id ity p r e v a ilin g a t th e tim e ;
l e a s t u n d e r 100% a n d h ig h e s t u n d e r 35% r e la tiv e h u m id ity .
D u s ta n (6) r e p o r t e d a n in c u b a tio n p e r io d of 3 3 .5 d a y s a t a n
a v e r a g e d a ily te m p e r a t u r e of 45. 6 ° F .

hi f a ll a n d s p rin g th e r e

21

TABLE I
T H E INCU BATION P E R IO D (DAYS) O F EGGS O F
' G R A PH O LIT H A M O LE ST A UN DER
D IF F E R E N T CONDITIONS
R e la tiv e H u m id ity
T e m p e r­
a tu r e
° F.

70%

100%
In c u ­
b a tio n
P e rio d

N o. of
O b ser­
v a tio n s

60

7 .0

83

65

5 .8 1

75

In cu ­
b a tio n
P e rio d

35%

N o. of
O b ser­
v a tio n s

In cu ­
b a tio n
P e r io d

N o. of
O b se r­
v a tio n s

7 .5

51

8 .0

36

237

5 .7 5

152

6 .0

161

4. 16

180

3 .9

138

4 .2

116

85

3 .3

117

3 .2 7

125

3. 4

124

94

2 .7 6

45

2 .7 5

44

-

-

95

3 .5

31

3 .3

42

-

-

F

ANALYSIS O F VARIANCE
f o r d a ta f o r 60° to 85° F .
D .F .

S. S.

M ean S.

T e m p e r a tu r e

3

3 1 .2 9

1 0 .4 3

H u m id ity

2

0 .2 4

0 .1 2

6

0 .3 5

0 .0 5 8 3

S o u rc e of v a r ia tio n

T e m p e r a tu r e x H u m id ity
E rro r

68

0 .0 0 8 6

:L 212.79++++
1 3 .9 5
6. 77

+

22

T A B L E I (C ontinued)

++++

H ig h ly s ig n if ic a n t

++

S ig n ific a n t

+

S ig n ific a n t

6

= / . 0086 = 0 .0 9 3

6m

= 0 .0 9 3 / ( /3 2 )

6

= 0 .0 9 3 /( /2 5 )

6

m3

m , -rn
1
3

= 0 .9 3 / ( 1 / 3 2 + 1 /2 5 ) = 0 .0 2 4
' '
1 1

t3_1

= (5 .2 6 - 4. 9 7 )/0 . 024 = 12

t2

= (5 .0 3 5 - 4. 9 7 0 )/0 . 025 = 2 .6

C o n c lu s io n s :

(i)

T he d iff e r e n c e b e tw e e n

100% a n d 35% r e l a ­

tiv e h u m id ity is h ig h ly s ig n ific a n t.
(ii) T he d iff e re n c e b e tw e e n

100% a n d 70% r e l a ­

tiv e h u m id ity is n o t s ig n ific a n t a t 1% le v e l
b u t is s lig h tly s ig n if ic a n t a t 5% le v e l.

23

1 0 0 /d a y s
40

8
7

days

4

P e rio d

5

in

6

30

20

3
2

1

35

45

55 l!f 65

75

Temperature

85
o

95

F.

FIG U R E 1
INCUBATION P E R IO D O F , AND INDEX OF D E V E L O P M E N T
F O R EGGS O F G. M O LESTA A T CONSTANT T E M P E R A ­
T U R E S AND 100% R E L A T IV E HUMIDITY

24

1 0 0 /d a y s
8

r 40

P e rio d

in

7
6

-3 0

5

- 25

4

•

20

-

10

3
2

1

35

45

55

65

75

Temperature

105
F.

FIG U R E 2
INCUBATION P E R IO D O F , AND INDEX O F D E V E L O P M E N T
F O R EGGS O F G. M O LESTA AT CONSTANT T E M P E R A ­
T U R E S AND 70% R E L A T IV E HUMIDITY

1 0 0 /d a y s
8

7

•35

6

•30

5

•25

4

- 20

3
2
1

35

45

55

65

75

Temperature

85
o

105

F.

FIG U R E 3
INCUBATION P E R IO D O F , AND INDEX O F D E V E L O P M E N T
F O R EGGS O F G. M O LESTA AT CONSTANT T E M P E R A ­
T U RES AND 35% R E L A T IV E HUMIDITY

a r e w ide f lu c tu a tio n s in d a ily t e m p e r a t u r e .

Som e d e v e lo p m e n t

w ould o c c u r a t h ig h e r t e m p e r a t u r e s , w h e r e a s i t w ould c e a s e
a t lo w e r t e m p e r a t u r e s , th e r e b y c o n s id e r a b ly le n g th e n in g the
in c u b a tio n p e rio d .
5 0 .5

o

In th e p r e s e n t in v e s tig a tio n s e g g s k e p t a t

F . h a tc h e d in 24 a n d 25 d a y s u n d e r 100% a n d 70% r e l a ­

tiv e h u m id ity , r e s p e c tiv e ly .

T h e g ra p h d ra w n by H a ru k a w a

(13) sh o w s th e th r e s h o ld of d e v e lo p m e n t to be 10° C . (50° F . )
w h ich a p p e a r s to be v e r y h ig h .

S h e lfo rd (23) gav e 44° to 49°

F . a s th e th r e s h o ld of d e v e lo p m e n t f o r th e c o d lin g m o th , C a rp o c a p s a p o m o n e lla , d e p en d in g u pon h u m id ity , o th e r w e a th e r f a c t o r s
a n d w ith th e g e n e r a tio n a n d th e in d iv id u a l.

T he e g g s of the

o r i e n t a l f r u i t m o th c a n , t h e r e f o r e , d e v e lo p a t lo w e r te m p e r a ­
t u r e s th a n th o s e of th e c o d lin g m o th .

(iii) U p p e r v ita l l i m i t ;

T he lin e s of in d ic e s of d e v e lo p m e n t in

F i g u r e s 1 to 3 a r e f a i r l y s t r a ig h t up to a t e m p e r a t u r e of 75
F . a t e a c h of th e t h r e e r e la tiv e h u m id itie s .

o

A f te r th is th e y

d e c lin e to w a rd s th e r ig h t, in d ic a tin g th a t a lth o u g h in c u b a tio n is
q u ic k e r a t t e m p e r a t u r e s ab o v e 75° F . , th e r a t e of d e v e lo p m e n t
is n o t m a in ta in e d u n ifo rm ly .

T he b e n d is l e a s t u n d e r 70% r e l ­

a tiv e hu m id ity a n d g r e a t e s t u n d e r 35% , show ing th e s tro n g in ­
flu e n c e of h u m id ity on th e r a t e of d e v e lo p m e n t.

G len n (11) in

th e c a s e of th e c o d lin g m o th fo u n d 76° F . a s th e te m p e r a tu r e
of m a x im u m d e v e lo p m e n t.

T h e tw o s p e c ie s s e e m to h av e a p ­

p r o x im a te ly th e s a m e te m p e r a t u r e f o r m a x im u m d e v e lo p m e n t.
T he u p p e r v i ta l lim it is s lig h tly ab o v e 95° F . , p ro b a b ly 9 6 °.
E g g s k e p t a t 95

o

F . f a ile d to h a tc h u n d e r 35% r e la tiv e h u m id ­

ity , a lth o u g h th e y h a tc h e d a t h ig h e r h u m id itie s .
98

o

E ggs kept a t

F . f o r 48 h o u r s d id n o t h a tc h u n d e r a n y r e la tiv e h u m id ­

ity b u t th e y w e re a b le to w ith s ta n d s h o r t e x p o s u r e s to a te r n p e r a t u r e of 105

o

F . a s show n in T a b le II.

E g g s la id d u rin g

th e e v e n in g a t a ro o m te m p e r a t u r e of 7 0 ° -8 0 ° F . w e re e x p o se d
in th e m o rn in g to t e m p e r a t u r e s of 98

o

F . a n d 105

o

F . , fo r

tw o h o u r s , fo u r h o u r s , s ix h o u r s , tw e n ty -o n e h o u r s , tw e n ty f o u r h o u r s , t h i r t y - s i x h o u r s , e t c . , a n d w e re th e n t r a n s f e r r e d
to th e r o o m t e m p e r a t u r e , t i l l h a tc h in g , if v ia b le .

A p o rtio n of

th e e g g s f r o m e a c h lo t w a s k e p t a s a c h e c k a t th e ro o m te m ­
p e ra tu re .

E x a m in a tio n of T a b le II sh o w s th a t a n e x p o s u re of

48 h o u r s to 98° F . w a s f a ta l f o r th e e g g s .
th a n 40 h o u r s w e re n o t so h a r m f u l.

E x p o s u r e s of l e s s

T he in c u b a tio n p e r io d w as

s ig n if ic a n tly le n g th e n e d on a c c o u n t of th e s e e x p o s u r e s .

It u s u ­

a lly r a n g e d f r o m 4 .5 to 5 .0 d a y s a s c o m p a re d to 3 .8 d a y s f o r
th e c h e c k , show ing th a t th e s e e x p o s u r e s r e t a r d e d o r a r r e s t e d

T A B L E II
E F F E C T O F SHORT E X PO SU R E S TO HIGH T E M P E R A T U R E ON T H E D U RA TIO N AND
V IA B ILIT Y O F EGGS O F G R A PH O L IT H A M O LESTA
E x p o s e d to H ig h T e m p e r a tu r e

C o n tro l

R e la tiv e H u m id ity
Pe­
H ig h
r io d
T em p
of
Em­
Expo­
p lo y e d
su re
F.
( H r s .)

95
98
98
98
98
105

48
24
36
40
48
4
6

100%
N o.
of
Eggs
Ex­
p o sed
50
30
30
30
30
30
30

70%

T o ta l
N o.
N o. of In cu —
of
Eggs
b a tio n E g g s
H a tc h e d P e ­
Ex­
r io d
posed
48
24
25
22
—

27
25

3 .0
4. 62
4 .7
4. 75
—

4 . 02
4 .5

50
30
30
30
30
30
30

35%

T o ta l
N o.
N o . of In c u of
E ggs
b a tio n E g g s
H a tc h e d P e ­
Ex­
r io d
p o sed
47
24
18
12
—

26
25

3 .0
4 .6 6
4 .8
5 .0
—

4 .1 2
4 .5

50
30
30
30
30
30
30

T o ta l
N o . of In cu ­
b a tio n
Eggs
H a tc h e d P e ­
r io d
29
17
4
—
—

18
18

3 .2 5
4. 75
5 .0
—
—

4 .3 7
4 .5

Per
In cu ­
c e n t b a tio n
V ia ­ P e r i o d
b ility (D ays)

96
98
98
98
98
98
98

4 .5
3 .8
4 .0
3 .8
3 .8
3 .7 5
3 .8

29
th e d e v e lo p m e n t of e g g s .

B la c k s p o ts , show ing a lm o s t fu ll

d e v e lo p m e n t of th e la r v a e in s id e egg s h e lls a p p e a re d in th e
m a j o r it y of c a s e s e v en th o u g h a c tu a l h a tc h in g did n o t o c c u r ,
in d ic a tin g th a t so m e d e v e lo p m e n t c o n tin u e d e v e n a t 9 8° F . an d
th a t i t i s s lig h tly ab o v e th e u p p e r v ita l lim i t f o r th e e g g s.
E g g s e x p o s e d f o r a d u r a tio n of tw e n ty -o n e h o u r s to 105° F .
h a tc h e d in 5 .3 to 5 .7 5 d a y s ; th o s e e x p o se d f o r s ix h o u r s took
only 4. 5 d a y s to h a tc h .

T he v ia b ility of e g g s e x p o se d to 105°

F . f o r tw e n ty -o n e h o u r s r a n g e d f r o m 43% u n d e r 100% r e l a ­
tiv e h u m id ity to 25% u n d e r a r e l a ti v e h u m id ity of 35% .

In

n a tu r e e v e n th o u g h th e r e l a ti v e h u m id ity of th e a i r m a y be
low , th e e g g s b ein g la id on g r e e n s u c c u le n t le a v e s a n d sh o o ts
m a y n o t s u f f e r to a n y a p p r e c ia b le e x te n t.

H o w e v e r, lo n g e r

e x p o s u r e s to 105° F . w o u ld a ff e c t th e v ia b ility of th e e g g s
<
v a ry a d v e rs e ly .

S h o r te r e x p o s u r e s to t e m p e r a t u r e s ab o v e 105

F . m a y be e q u a lly h a r m f u l.

(b) E f f e c t of h u m id ity on d e v e lo p m e n t of e g g s

T h e in flu e n c e of h u m id ity on th e r a t e of d e v e lo p m e n t of
e g g s is g iv e n in T a b le s I a n d II.

T he d e v e lo p m e n t is s lig h tly

m o r e u n d e r 70% r e la tiv e h u m id ity a t m e d iu m te m p e r a t u r e s .

o

T he d if f e re n c e is n o t w e ll m a r k e d , e s p e c ia lly a t h ig h e r te m ­
p e ra tu re s .

G e n e r a lly e g g s k e p t u n d e r 70% r e la tiv e h u m id ity

h a tc h e d a co u p le of h o u r s b e fo re o th e r s h a tc h in g u n d e r 35%
r e la tiv e h u m id ity a n d a t a b o u t th e s a m e tim e u n d e r s a t u r a t e d
c o n d itio n s .

T h e s e o b s e r v a tio n s show th a t th e e g g - s h e ll of th is

in s e c t d o e s n o t e a s i l y a llo w lo s s of m o is tu r e f r o m th e egg co n ­
te n ts .

T h e f l a t a n d s c a l e - li k e a p p e a ra n c e of th e e g g s m a y be

q u ite h e lp fu l in th is r e s p e c t .

F u r t h e r m o r e , a s th e e g g s a r e

la id on g r e e n s u c c u le n t t i s s u e s of th e p la n t th e y a r e in a sa fe
p o s itio n to e s c a p e d a m a g e f r o m low h u m id ity of th e a i r .

(c) E f fe c t of te m p e r a t u r e a n d h u m id ity on v ia b ility

T he v ia b ility of e g g s of G ra p h o lith a m o le s ta v a r i e s c o n ­
s id e r a b ly u n d e r d if f e r e n t c o n d itio n s p a r t i c u l a r l y a t a d v e r s e te m ­
p e ra tu re s .

S te a r n s (26) r e p o r t e d 5 7 .9 8 % , 5 6 .8 4 % , 57.14% a n d

66. 1% v ia b ility of e g g s f o r th e f i r s t , se c o n d , th ir d a n d fo u rth
b ro o d r e s p e c tiv e ly .

S te a r n s a n d N e is w a n d e r (28) in O hio found

th e v ia b ility of e g g s to be 9 7 .5 7 % , 9 8 .2 % , 9 6 .6 % a n d 91.3%
f o r th e s e c o n d , th ir d , f o u r th a n d fifth b ro o d r e s p e c tiv e ly .
D a ta on th e v ia b ility of e g g s o b ta in e d d u rin g th e p r e s e n t
in v e s tig a tio n a r e g iv e n in T a b le s II a n d III a n d d e p ic te d g ra p h ic a lly

TABLE n i
THE V IA BILITY O F EGGS O F G R A PH O LIT H A M O LE ST A U N D ER D IF F E R E N T CONDITIONS
R e la tiv e H u m id ity
T em ­
p e r­
a tu r e
° F.

T o ta l
N o.
o£
Eggs

35%

70%

100%
N o. of
Eggs
H a tc h e d

Per
cent
V ia ­
b ility
90

T o ta l
N o.
of
Eggs

N o. of
Eggs
H a tc h e d

Per
cent
V ia ­
b ility

68

51

75

N o. of
Eggs
H a tc h e d

Per
cent
V ia ­
b ility

50

36

72

T o ta l
N o.
of
E ggs

60

92

83

65

256

237

9 2 .5

196

152

7 7 .5

208

161

7 7 .4

75

183

180

9 8 .3

140

138

9 8 .6

132

116

8 7 .8

85

120

117

9 7 .5

128

125

9 7 .5

160

124

7 7 .5

94

50

45

9 0 .0

50

44

88

50

0

0 .0

95

90

31

3 4 .0

80

42

5 2 .5

60

0

0 .0

u>

32
in F i g u r e s 4 a n d 5.

It w a s 90% , 9 2 .5 % , 9 8 .3 % , 9 7 .5 % a n d

90% u n d e r s a t u r a t e d r e l a ti v e h u m id ity a t c o n s ta n t te m p e r a t u r e s
of 60 , 65 , 75 , 85

a n d 94

F . , r e s p e c tiv e ly .

T he c o r r e s ­

p o n d in g v a lu e s u n d e r r e l a ti v e ly d r y c o n d itio n s of 35% r e la tiv e
h u m id ity w e re 72% , 7 7 .4 % , 8 7 .8 % , 7 7 .5 % a n d 0 .0 % .
c o n s ta n t t e m p e r a t u r e of 95

o

At a

F . th e v ia b ility w as 34% , 5 2 .5 %

a n d 0 .0 % u n d e r r e l a ti v e h u m id itie s of 100% , 70% a n d 35% ,
r e s p e c tiv e ly .

No e g g s h a tc h e d w hen e x p o s e d to 98° F . f o r

40 h o u r s u n d e r 35% r e l a ti v e h u m id ity , w h e re a s 7 3 .3 % a n d 40%
h a tc h e d u n d e r 100% r e l a ti v e h u m id ity a n d 70% r e la tiv e h u m id ity , r e s p e c tiv e ly .

A n e x p o s u re of 21 h o u r s a t 105

o

F.

re d u c e d

th e v ia b ility of e g g s to 43% u n d e r h ig h e r h u m id itie s a n d to 25%
u n d e r th e low h u m id ity of 35% .

It is e v id e n t f r o m th e s e d a ta

th a t th e e g g s of th e o r i e n t a l f r u i t m o th c a n to le r a te f a i r l y h ig h
t e m p e r a t u r e s a n d low h u m id itie s .

U n d e r m e d iu m te m p e r a t u r e s

th e v ia b ility w a s s e ld o m l e s s th a n 75% , e v e n u n d e r th e lo w e st
h u m id ity t r i e d .

N e a r th e u p p e r v ita l lim it, th e d e le te r io u s e f­

f e c t of low h u m id ity b e c a m e m a r k e d ly p ro n o u n c e d a s eg g s u n d e r
35% r e l a ti v e h u m id ity f a ile d to h a tc h a t 94° a n d 95° F .

N ear

s a t u r a t e d r e l a ti v e h u m id itie s a r e , th e r e f o r e , b e n e fic ia l and
d r i e r c o n d itio n s a r e h a rm f u l.

T he in flu e n c e of r e la tiv e h u m id ity

100 n

c
o

4>

u
4)

*

80 -

>S
-M
•H

75 -

Xi

cd

•H

__ A

>

7 0

R. H. 35%
*

30 25 ■
35

45

55

65

75

rr,

Temperature

85
O

95

„

F.

FIG U R E 4
V IA B ILITY O F EGGS OF G. M O LESTA
UN DER D IF F E R E N T CONDITIONS

105

34

100 n

60° F.
65° F.

80 -

85°

Per

cent

viability

90 -

70 ■
30 •
25 ■
0 ■20

95° F.
—

:

,
70

35
Percent

relative

humidity

FIG U R E 5
V IA B ILIT Y O F EGGS O F G. M O LESTA
UN DER D IF F E R E N T CONDITIONS

;
100

s e e m e d to be m o r e m a r k e d on th e v ia b ility of th e e g g s th a n
on th e in c u b a tio n p e rio d .

2.

L a r v a l S tage

(a) E ffe c t of te m p e r a tu r e on d e v e lo p m e n t

(i) D u r a tio n ;

T he l a r v a l p e r io d of th e o r ie n ta l f r u i t m o th in

th is d is c u s s io n is ta k e n to m e a n th e g ro w in g p e rio d , th e i n t e r ­
v a l b etw een' th e e c lo s io n a n d the tim e th e l a r v a s t a r t s sp in n in g
a co co o n .

T he sp in n in g of th e c o co o n m a y h av e b e e n e ith e r

f o r im m e d ia te p u p a tio n o r f o r th e p u rp o s e of h ib e rn a tio n .

T he

fe e d in g p e r io d of th e la r v a e v a r i e s c o n s id e r a b ly in n a tu r e a t
d if f e r e n t p la c e s d e p en d in g upon th e a ltitu d e , la titu d e of the
p la c e a n d th e tim e of th e y e a r .

T he q u a n tity , q u a lity a n d k ind

of fo o d h a v e b e e n know n to in flu e n c e th e le n g th of th is p e rio d .
A p a r t f r o m th e ab o v e f a c t o r s t h e r e a r e l a r g e in d iv id u a l v a r i ­
a tio n s w ith in one lo t of la r v a e k e p t u n d e r u n ifo rm c o n d itio n s.
T he l a r v a e h a d b e en s tu d ie d e x te n s iv e ly in d iff e re n t
s ta te s of th e U. S. A . b u t th e d u ra tio n s w e re g iv en g e n e r a lly
a c c o rd in g to th e b ro o d .

T h ey w e re r e a r e d in th e in s e c ta r y

u n d e r u n c o n tro lle d c o n d itio n s of t e m p e r a t u r e .

D ic k so n (5) s tu d ­

ie d th e m u n d e r c o n s ta n t te m p e r a t u r e s b u t he d id not m e n tio n '

th e d u r a tio n of th e fe e d in g p e rio d .

H a ru k a w a (13) r e p o r t e d the

g ro w in g p e r io d u n d e r m o r e o r l e s s c o n s ta n t t e m p e r a t u r e s f r o m
J a p a n , a lth o u g h he w a s n o t s u r e of a c c u r a c y of h is e x p e r i ­
m e n ts a n d h e fo u n d it d iffic u lt to a r r i v e a t d e fin ite c o n c lu s io n s
b a s e d u p on th o s e r e s u l t s .

H e fo u n d th e g ro w in g p e rio d to be

1 0 .8 d a y s a t 3 3 ° ' C . , 8 .6 d a y s a t 3 0 °, 9 d a y s a t 2 7 °, 1 0 .3 d a y s
a t 2 5 ° , 1 5 .4 d a y s a t 2 0 ° a n d 2 1 .8 d a y s a t 17° C .

S te a r n s (26)

w hile w o rk in g in V irg in ia fo und i t to be 1 8 .9 8 d a y s on a n a v e r a g e , w ith a m in im u m of 9 d a y s a n d a m a x im u m of 30 d a y s f o r
th e f i r s t b ro o d .

C o rre s p o n d in g d a ta g iv e n by h im f o r th e s e c ­

o nd b ro o d w as 1 4 .5 7 d a y s , 9 d a y s a n d 22 d a y s ; f o r th e th ir d
g e n e r a tio n 17. 1 d a y s , 11 d a y s a n d 22 d a y s , f o r th e fo u r th g e n ­
e r a t io n 4 5 .4 3 d a y s , 25 d a y s a n d 69 d a y s r e s p e c tiv e ly .

S te a r n s

a n d P e t e r s o n (27) in N ew J e r s e y r e c o r d e d a m a x im u m fe e d in g
p e r io d of 25 d a y s in 1924, 34 d a y s in 1925, a m in im u m of 8
d a y s e a c h y e a r a n d a v e r a g e s of 1 4 .4 a n d 1 4 .3 d a y s , r e s p e c tiv e ly .
In 1924 th e m e a n d a ily t e m p e r a t u r e f o r th e fe e d in g p e rio d of
th is b ro o d w a s 6 5 .4 ° F . ; in 1925, 7 0 .1 ° F .

P e te rs o n and

H a e u s s l e r (20) found th a t la te in th e s e a s o n in N ew J e r s e y ,
th e o v e rw in te rin g l a r v a e in p a r t i c u l a r r e q u ir e d 50 -1 1 5 d a y s to
b e c o m e f u ll g ro w n .

A t a n a v e r a g e t e m p e r a t u r e of 6 6 .5

o

F .,

D u s ta n (6), w o rk in g in O n ta rio , C a n a d a , found th e l a r v a l fe e d in g
p e r io d to be 28 d a y s w h en fe d on s to r a g e a p p le s a n d 20 d a y s
w hen s u p p lie d w ith p e a c h s h o o ts .
te m p e r a t u r e of 46. 5

In la te f a l l a t a n a v e ra g e

F . he fo u n d th a t so m e c a t e r p i l l a r s r e ­

q u ir e d 8 0 -9 2 d a y s to b e c o m e f u ll g ro w n .
In th e p r e s e n t in v e s tig a tio n th e la r v a e w e re fe d on
s to r e d a p p le s , a n d w e re r e a r e d a t c o n s ta n t te m p e r a t u r e s of
o
o
o
o
65 , 75 , 85 a n d 95 F .

A s th e la r v a e a lw a y s fe e d by b o rin g

in to th e fo o d s a t u r a t e d w ith m o is tu r e th e y co u ld n o t be g ro w n
on s e m i - d r y fo o d .

T he r e s u l t s a r e g iv e n in T a b le TV a n d

sh o w n g r a p h ic a lly in F i g u r e s 6 a n d 7.

T he a v e r a g e la r v a l

p e r io d w a s 3 6 .8 1 d a y s a t 65° F . , 2 4 .4 1 d a y s a t 7 5 °, 2 0 .4 5
d a y s a t 8 5 ° a n d 1 8 .0 d a y s a t 95° F . , r e s p e c tiv e ly .

T he c o r ­

re s p o n d in g m a x im u m p e r io d w a s 58 d a y s , 36 d a y s , 38 d a y s a n d
25 d a y s; a n d th e m in im u m of 22 d a y s , 14 d a y s , 10 d a y s an d
11 d a y s , r e s p e c tiv e ly .
f o r m ly up to 7 5 ° F .

T he r a t e of d e v e lo p m e n t in c r e a s e d u n i­
A bove 7 5 ° F . th e s a m e r a t e of d e v e lo p -

m e n t w a s n o t m a in ta in e d .

A c o n s ta n t t e m p e r a tu r e of 75

o

F .,

th u s a p p e a r s to be v e r y c lo s e to th e o p tim u m te m p e r a tu r e f o r
l a r v a l d e v e lo p m e n t, th e o p tim u m ra n g e p ro b a b ly t e r m in a te s a t
8 5 ° F . o r e v e n a t a lo w e r t e m p e r a t u r e .

38
T A B L E IV
TH E DU RATION AND V IA B ILIT Y O F L A R V A L STA G E O F
G R A PH O L IT H A M O LE ST A UN D ER
D IF F E R E N T CONDITIONS

N o. of
L arv a e
K ept

N o. of
L arv a e
W hich
Spun
C ocoons

V ia b ility
P e rc e n t

22

7580

958

12. 65

36

14

7706

1286

1 6 .7

2 0 .4 5

38

10

6429

1182

1 8 .4

1 8 .0

25

11

1538

228

1 4 .8

T ern p e ra tu r e
° F.

L a r v a l P e r i o d in D ay s
A v e rag e

65

3 6 .8 1

58

75

2 4 .4 1

85
95

M axim u m

M in im u m

39
6

1 0 0 /d a y s

V)

tK
<d
Q

40-

c
•H

*0
O

bo
C
•°

v
v
Ui

20 -

35

45

55

65

75

Temperature

85

95

105

F.

FIG U R E 6
T H E F E E D IN G P E R IO D OF L A R V A E IN A P P L E S AT CONSTANT
T E M P E R A T U R E S AND INDEX OF LA R V A L D E V E L O P M E N T
O F G. M O LESTA

40

25

cent

20

Viability

pe r

15

10

5

35

45

55

65

75

__

Temperature

85
o

105

„

F.

FIG U R E 7
V IA B ILITY O F LA RV A E O F G. M O L E ST A , REA RED ON A P P L E S
A T CONSTANT T E M P E R A T U R E S

41
(ii) T h r e s h o ld of d e v e lo p m e n t:

T he r e la tio n of l a r v a l fe e d in g

p e r io d to t e m p e r a t u r e i s show n in F ig u r e 6.

T he r e c i p r o c a ls

of th e p e rio d s m u ltip lie d by one h u n d re d a r e a ls o p lo tte d .
lin e i s c a lle d th e in d e x of d e v e lo p m e n t.

T h is

In F ig u r e 3 g iv e n by

H a ru k a w a (13) th e lin e of in d e x of d e v e lo p m e n t c r o s s e s th e
te m p e r a t u r e a x is a t 10

o

C . (50

o

F . ) w h ich s e e m s to be h ig h .

H o w e v e r, h e h im s e lf w a s n o t s u r e of the a c c u r a c y of h is e x ­
p e rim e n ts .

T h is lin e , a c c o rd in g to p r e s e n t e x p e r im e n ts ,

th e te m p e r a t u r e a x is a t 4 3 .5

o

F.

o r e t i c a l th r e s h o ld of d e v e lo p m e n t.
lie

s lig h tly belo w

4 3 .5 °

F.

c ro sse s

T h is te m p e r a tu r e is the th e ­
T he a c tu a l th r e s h o ld m a y

T h is t e m p e r a tu r e

is

0 .5

to

3 . 5 ° lo w e r th a n th a t f o r th e e g g s ( F ig u r e s 1-3) d e p en d in g upon
th e r e l a ti v e h u m id ity to w h ich th e e g g s w e re e x p o se d .

T h is

w ould in d ic a te th a t th e l a r v a e co n tin u e to d e v e lo p a t te m p e r a ­
t u r e s lo w e r th a n th o s e f o r e g g s .

T h is e n a b le s th e la r v a e

h a tc h in g la te in th e s e a s o n in f a ll to c o n tin u e to d e v e lo p f o r a
lo n g e r p e r io d a n d th u s h e lp s th e m to b e c o m e fu ll gro w n b e fo re
e n te r in g in to d ia p a u s e .
G len n (11) a n d S h e lfo rd (23) fo u n d 4 7 .5 ° F . a s th e th e ­
o r e t i c a l th r e s h o ld of d e v e lo p m e n t f o r th e l a r v a e of th e co d lin g
m o th .

In c a lc u la tin g day d e g r e e s , th e y e m p lo y e d 50

F . a s the

s t a r ti n g p o in t.

T h u s , la r v a e of th e o r i e n t a l f r u i t m o th c a n

d e v e lo p a t t e m p e r a t u r e s lo w e r th a n th o s e f o r th e l a r v a e of th e
c o d lin g m o th .

T h e f o r m e r c o u ld c o n tin u e to d e v e lo p f o r a

lo n g e r p e r io d in la te f a ll a s c o m p a re d to th o s e of th e c o d lin g
m o th .

T he l a r v a e of th e c o d lin g m o th in n a tu r e go in to h i b e r ­

n a tio n m u c h e a r l i e r th a n th o se of th e o r ie n ta l f r u i t m o th .

T h is

p r o b a b ly is one of th e r e a s o n s f o r th e s m a ll e r n u m b e r of g e n ­
e r a t io n s in th e c a s e of th e c o d lin g m o th u n d e r s i m i l a r s e t of
c o n d itio n s .

(b) E f fe c t of t e m p e r a t u r e on v ia b ility

I n fo rm a tio n on th e e ffe c t of t e m p e r a t u r e on l a r v a l v ia ­
b ility is r a t h e r s c a n ty .

H a r u k a w 's (13) d a ta b a s e d on a s m a ll

n u m b e r of in d iv id u a ls show th a t th e r e w a s 14% m o r ta li t y a t
2 0 ° C . , 2 0 .8 % a t 2 5 ° C. , 1 2 .6 % a t 2 7 ° C . , 40% a t 3 3 ° C.
a n d 8 1 .2 % a t 3 4 ° C .

S te a r n s a n d N e is w a n d e r (28) s tu d ie d th e

e ff e c t o f fo o d on th e l a r v a l v ia b ility .

T h e y found th a t v ia b il­

ity w a s 44% , 33% , 5 6 .9 % , 12% a n d 13.3% w hen th e la r v a e w e re
fe d on p e a c h , p lu m , a p p le , p e a r a n d q u in c e , r e s p e c tiv e ly .
In th e p r e s e n t e x p e r im e n ts th e l a r v a l v ia b ility a s show n
in T a b le IV a n d F ig u r e 7 w a s found to be 1 2 .6 5 % , 1 6 .7 % , 18.4%

a n d 1 4 .8 % a t 65 , 75 , 85

a n d 95

F . , r e s p e c tiv e ly .

T hese

f i g u r e s a r e r a t h e r low , p ro b a b ly b e c a u s e th e y a r e b a s e d on
th e r e a r i n g of s e v e r a l th o u s a n d young la r v a e in s m a ll c a g e s .
G ro w th of fu n g u s a n d f r e e w a te r a c c u m u la tin g f r o m a p p le s w e re
a ls o r e s p o n s ib le in re d u c in g th e n u m b e r of la r v a e r e a c h in g
m a tu r ity .

In c a s e s w h e re a few in d iv id u a ls w e re r e a r e d the

v ia b ility w a s s o m e tim e s a s h ig h a s 5 0 -7 0 % .

In n a tu r e a ls o

it w ould b e e x p e c te d th a t th e m o r ta li t y of th e la r v a e w ould be
h ig h on a c c o u n t of th e u n a v a ila b ility of th e r ig h t ty p e of food
a t th e p r o p e r t im e , d riv in g r a i n s , d i s e a s e s , p a r a s i t e s , p r e d a to r s
a n d s e v e r a l unknow n f a c t o r s .

G u m m o s is f r o m th e tw ig s a n d

f r u i t s of p e a c h in ju r e d by l a r v a l b o rin g s is of c o m m o n o c c u r ­
r e n c e a n d n o t in fre q u e n tly c r e a t e s c o n d itio n s u n s u ita b le f o r
th e s u r v iv a l of th e la r v a e fe e d in g th e r e in .

3.

P u p a l S tage

T h e fu ll g ro w n l a r v a e of th e o r i e n t a l f r u i t m o th lea v e
th e f r u i t in w h ic h th e y fe e d a n d c o m e to th e to p of th e r e a r in g
d is h f o r th e p u rp o s e of sp in n in g c o c o o n s.

T h e s e la r v a e w e re

re m o v e d e v e r y d ay f r o m d is h e s k e p t a t v a r io u s c o n s ta n t te m ­
p e ra tu re s .

T h ey w e re c o u n te d a n d p u t in s m a ll g la s s v ia ls

44
c o n ta in in g s h o r t s t r i p s of c o r r u g a te d p a p e r .
s p in c o c o o n s.

T h e y w ould r e a d ily

T he p e r io d a f t e r a l a r v a s t a r t s sp in n in g up to

th e tim e i t p u p a te s in s id e th e c o co o n is c a lle d th e p re p u p a l
p e r io d .

S e v e ra l w o r k e r s in th e p a s t h av e m e n tio n e d th is d u r a ­

tio n s e p a r a t e l y f r o m th e p u p a l p e rio d .

T h is n e c e s s i t a t e s t e a r ­

in g th e c o co o n a n d d is tu rb in g th e la r v a e o r th e u se of s e m i­
tra n s p a re n t p a p e r.

F o r th e p r e s e n t in v e s tig a tio n it w a s n o t

c o n s id e r e d n e c e s s a r y to d e te r m in e th is p e r io d a p a r t f r o m the
p u p a l p e r io d .

W h e n e v e r th e p u p a l p e r io d o r p u p a l sta g e is

m e n tio n e d h e r e a f t e r , i t sh o u ld be ta k e n to m e a n th e e n tir e
p e r io d a f t e r th e l a r v a s t a r t e d sp in n in g a c o co o n to i t s fin a l
e m e r g e n c e a s a m o th .
T he p u p ae a r e c o n s id e r a b ly in flu e n c e d by te m p e r a tu r e
a n d h u m id ity , p e rh a p s m o re so th a n th e e g g s.

S te a r n s (26)

fo u n d th e p u p a l p e r io d to be 1 4 .4 9 d a y s , 1 2 .8 8 d a y s a n d 1 2 .5 5
d a y s f o r th e f i r s t , se c o n d a n d t h ir d b ro o d r e s p e c tiv e ly in one
y e a r in n o r t h e r n V irg in ia .

In a n o th e r y e a r th e c o rre s p o n d in g

p e r io d w a s 1 5 .2 4 d a y s , 1 3 .9 4 d a y s , 1 5 .0 2 d a y s r e s p e c tiv e ly .
S te a r n s a n d N e is w a n d e r (28) w o rk in g in O hio found i t to be
1 5 .2 d a y s , 1 6 .7 d a y s a n d 1 6 .5 d a y s f o r th e se c o n d , th ir d a n d
f o u r th b ro o d , r e s p e c tiv e ly in 1927.

F o r th e s u m m e r in d iv id u a ls

45
th e y m e n tio n e d 32 d a y s a s th e m a x im u m a n d 7 d a y s a s th e
m in im u m .

P e t e r s o n a n d H a e u s s le r (20) found i t to v a r y f r o m

8 to 33 d a y s w ith a n a v e r a g e of 14 d a y s u n d e r N ew J e r s e y
c o n d itio n s .

T h e y i l l u s t r a t e d th e r e la tio n s h ip b e tw e e n th e a v e r ­

a g e t e m p e r a t u r e s e x is tin g d u rin g s u m m e r a n d the p u p a l p e rio d .
It w a s 1 0 .5 d a y s a t 8 3 ° F . , 1 2 .5 d a y s a t 7 5° F . a n d 16 d a y s
a t 68° F .

H a ru k a w a (13) f r o m J a p a n r e p o r te d it a s 8 .4 d a y s

a t 3 3 ° C . , 7 .2 d a y s a t 30° C . , 8 .9 d a y s a t 2 9 ° C . , 10 d a y s
a t 2 5 ° C . , 1 4 .6 d a y s a t 2 0 ° C. a n d 2 1 .5 d a y s a t 1 7 .1 ° - 1 7 .4 °
C.

He r e a l i z e d th a t h is r e s u l t s w e re n o t s a t is f a c to r i l y r e g u la r

a b o v e 28

o

C . , a lth o u g h he d id n o t give a n y e x p la n a tio n f o r the

irre g u la ritie s .
T he r e s u l t s f r o m th e p r e s e n t in v e s tig a tio n u n d e r v a rio u s
c o n s ta n t te m p e r a t u r e c o m b in a tio n s a n d r e la tiv e h u m id itie s a r e
g iv e n in T a b le s V a n d VI a n d a r e show n in F i g u r e s 8 -1 3 .

(a) E ffe c t of te m p e r a tu r e on d e v e lo p m e n t

(i) D u ra tio n :

T h e r e w e re tw o s e t s of e x p e r im e n ts in o r d e r to

fin d o u t th e in flu e n c e of t e m p e r a t u r e on th e p u p a l s ta g e .

In

one s e t th e p u p ae w e re k e p t a t th e s a m e te m p e r a tu r e a t w hich
th e e g g s a n d la r v a e w e re g ro w n .

U n d e r th e s e c o n d itio n s the

46
TABLE V
P U P A L P E R IO D (DAYS) O F G R A PH O LITH A M O LESTA
U N D ER D IF F E R E N T CONDITIONS
T e m p e r a tu r e
° F.

R e la tiv e Hum idity70%

100%
Pupal
S tag e
at

Eggs
and
L arv a e
R e are d
at

N o. of
O b ser­
v a tio n s

65

65

32

75

75

85
95

85

A v e r­
N o. of
ag e
O b ser­
Pe­
v a tio n s
r io d

35%
A v e r­
A v e r­
N o. of
ag e
ag e
O b se r­
Pe­
Pe­
v a tio n s
rio d
rio d

19

56

2 0 .8

18

2 4 .5

132

1 4 .3

50

15

78

1 7.3

85

134

1 2 .0

94

1 3 .0

90

1 4 .2

95

12

1 1 .0

25

1 1 .5

7

1 2 .5

75

104

1 1 .2

94

12

No m o th
e m e r g e d out
of 135 pupae
One
(out of
78
p upae)

85

65

44

1 6 .4

24

22

65

85

76

2 1 .5

38

2 3 .2

30

15

2 5 .2

T A B L E VI
V IA B ILIT Y O F P U P A E O F G R A PH O LIT H A M O LE ST A
U N D E R D IF F E R E N T CONDITIONS
T e m p e r a tu r e
° F.

R e la tiv e H u m id ity

P re
Eggs
an d
Pupae
and
L arv a e
Pupae R e are d
at
at

N o. of
N o.
M oths
of
Pupae E m e rg ed

35%

70%

100%
V ia ­
b ility
Per
cent

N o.
N o. of
of
M o th s
Pupae E m e rg e d

V ia ­
b ility
Per
cent

N o.
N o. of
of
M o th s
Pupae E m e rg e d

V ia ­
b ility
Per
cent

65

65

268

112

4 1 .8

392

96

2 4 .5

214

18

8 .4

75

75

390

280

7 1 .8

357

180

5 0 .4

256

104

4 0 .6

85

85

196

134

6 8 .3 6

176

96

5 4 .5 5

294

94

3 1 .9 7

95

95

86

12

1 4 .0

63

25

39. 6

62

7

1 1 .3

85

75

184

128

6 9 .5 6

270

136

5 0 .3 7

260

0

0 .0

85

65

96

44

4 5 .8 3

120

44

36. 7

78

1

1 .2

65

85

266

122

4 5 .8 6

160

42

2 6 .2 5

.198

30

1 5 .1

1 0 0 /d a y s

28-

days

16-

P e rio d

20

in

24-

-

12-

35

45

55

65

75

Temperature

85

95

105

F.

FIG U R E 8
P U P A L P E R IO D AND INDEX OF D E V E L O PM E N T FO R
P U P A E OF G. M O LESTA AT CONSTANT
T E M P E R A T U R E S AND 100%
R E L A T IV E HUM IDITY

49

1 0 0 /d a y s
10
’

28-

days

16-

P e rio d

20-

in

24-

12-

35

45

55

65

75

85

105

Temperature

F IG U R E 9
P U P A L P E R IO D AND INDEX O F D E V E L O P M E N T FO R
P U P A E O F G. M O LESTA AT CONSTANT
T E M P E R A T U R E S AND 70% R E L A T IV E
HUM IDITY

50

9'

24-

8

days

20

•

7

16-

6

12

5

P e rio d

28-

in

1 0 0 /d a y s
10

-

4

35

45

55

65

75

85

95

105

Tem perature

FIG U R E 10
P U P A L PE R IO D AND INDEX O F D E V E L O P M E N T FO R
P U P A E O F G. M O LESTA AT CONSTANT
T E M P E R A T U R E S AND 35% R E L A T IV E
HUM IDITY

51

90

.

80702
u

60-

a,
A

50 R .H . 100%

•H

r*

>
20

-

10

-

35

45

55

65

75

Tem perature

85

95

105

F.

FIG U R E 11
V IA B ILIT Y O F P U P A E O F G. M O LESTA
U N D ER D IF F E R E N T CONDITIONS

52

100
90 -

cent

80
.o
,o

70 -

>

•Viability

Per

60 50 65° F.

40 ■
30 *
20

•

Nr
10

95° F.

•

20

30 35
Percent

70
relative

100

humidity

FIG U R E 12
V IA B ILIT Y O F P U P A E O F _G. M O LESTA UNDER D IF F E R E N T
CONDITIONS (E g g s a n d la r v a e r e a r e d a t th e sa m e
t e m p e r a t u r e a t w hich pupae w e re kept)

53

100

E g g s and la r v a e
re a re d at

P u p ae
kept a t

90 ■
80 ■

c
O
u

70 ■
60 50 -

4->
•H
"
JQ

40 ■

rt

>

30 *
20

-

10

*

20

70

35
Per

cent

relative

100

humidity

FIG U R E 13
V IA B ILIT Y O F P U P A E O F G. M O LESTA UNDER VARIOUS CONDITIONS
(E g g s a n d la r v a e r e a r e d a t a te m p e r a tu r e d iffe re n t
f r o m th e one a t w hich pupae w e re kept)

p u p a l d u r a tio n w a s 19 d a y s , 1 4 .3 d a y s , 1 2 .0 d a y s a n d 1 1 .0
d a y s a t a c o n s ta n t t e m p e r a tu r e of 6 5 °, 7 5 °, 8 5 ° a n d 95° F . ,
r e s p e c t iv e ly , u n d e r a r e la tiv e h u m id ity of 100% .

In th e se c o n d

s e t th e l a r v a e r e a r e d a t 6 5 ° a n d 75° F . w e re t r a n s f e r r e d to
8 5 ° F . , a n d th o s e fe d a t 8 5 ° ta k e n to 65° F . d u rin g t h e i r c o ­
c o o n p e r io d .

T he d u r a tio n u n d e r 100% r e la tiv e h u m id ity w as

1 1 .2 d a y s a t 8 5 ° F .

( la rv a e f r o m 7 5 °), 1 6 .4 d a y s a t 85° F .

( la r v a e f r o m 65° F . ) a n d 2 1 .5 d a y s a t 65° F . (la rv a e fr o m
85

o

.

F .) .

U n d e r th e s t r a ig h t s e t th e d u ra tio n c o n tin u ed to d e ­

c r e a s e w ith th e r i s e of t e m p e r a t u r e .
u n if o r m e s p e c ia lly b e tw e e n 75

o

a n d 95

T he d e c r e a s e w as n o t
o

F.

F r o m th e se co n d

s e t i t is c l e a r th a t th e t e m p e r a t u r e a t w h ich th e la r v a e w e re
g ro w n h a d a d is tin c t in flu e n c e on th e d u ra tio n of th e pupae k ep t
a t a n o th e r t e m p e r a t u r e .

L a r v a e g ro w n a t 65° F . h a d a lo n g e r

d u r a tio n , a lm o s t one an d a h a lf tim e s g r e a t e r a s c o m p a re d to
th o s e fe d a t 75
each c ase .

o

F . a n d s u b s e q u e n tly t r a n s f e r r e d to 85

o

F . in

A n o th e r i n te r e s tin g f e a tu r e is th a t th e p upae fo rm e d

f r o m l a r v a e g ro w n a t 65° F . a n d k e p t a t 65° F . h ad a s h o r te r
d u r a tio n a s c o m p a re d to th o s e w h ich w e re t r a n s f e r r e d f r o m a
h ig h te m p e r a t u r e of 85° F . to a low te m p e r a tu r e of 65° F .
d u rin g t h e i r c o co o n p e rio d .

T h u s r i s i n g te m p e r a t u r e s in sp rin g

s h o r te n th e p u p a l d u ra tio n a n d d e c r e a s in g t e m p e r a t u r e s in f a ll

55
le n g th e n th e p u p a l p e rio d .

In th e f o r m e r c a s e th e i n t e r e s t of

th e s p e c ie s l i e s in b r in g f o r t h i t s a d u lts , a n d c o n se q u e n tly
e g g s , e a r l y in th e s e a s o n to ta k e a d v a n ta g e of n ew g ro w th a n d
to c o m p le te m o r e g e n e r a tio n s , w h e r e a s , in th e l a t t e r c a s e th e r e
i s a g r e a t e r te n d e n c y to a r r e s t d e v e lo p m e n t due to a p p ro a c h in g
u n fa v o ra b le w e a th e r c o n d itio n s .

(ii) T h r e s h o ld of d e v e lo p m e n t:

A n e x a m in a tio n of F ig u r e s 8 -1 0

sh o w s th a t th e th e o r e ti c a l th r e s h o ld of d e v e lo p m e n t f o r the
p u p a e l i e s a t 4 6 .5 ° F . , 4 9 ° a n d 5 2 .5 ° F . u n d e r r e la tiv e h u ­
m id itie s of 100% , 70% a n d 35% , r e s p e c tiv e ly .
s e e m to be v e r y s ig n ific a n t.

T h e s e f ig u r e s

U n d e r m o is t c o n d itio n s th e pupae

w e re a b le to co n tin u e d e v e lo p m e n t a t lo w e r te m p e r a t u r e s a s
c o m p a r e d to th o se e x p o se d to a d r y s e t of c o n d itio n s.

In a r e a s

w ith m o is t c lim a te , p a r t i c u l a r l y in th o s e h a v in g r e la tiv e h u m id ­
i t i e s v a ry in g f r o m 80-90% th e p e s t c o u ld s t a r t d e v e lo p m e n t
e a r l y in s p r in g a n d th u s i n c r e a s e to l a r g e p r o p o r tio n s a n d c a u se
s e rio u s d am ag e.

On th e o th e r h a n d , u n d e r d r y c o n d itio n s th e

in s e c t w ould c o n tin u e to b e in a c tiv e u n til th e te m p e r a tu r e h a s
r i s e n w e ll a b o v e 5 2 .5 ° F . a n d w ould la g b e h in d a n d n o t be a b le
to b u ild up i t s p o p u la tio n q u ic k ly .

T h e th r e s h o ld of d e v e lo p m e n t f o r th e p u p ae is h ig h e r
th a n th a t f o r e g g s o r l a r v a e .

T h is a p p e a r s to be a n o th e r in ­

s u r a n c e p ro v id e d by th e s p e c ie s to tid e o v e r in c le m e n t w e a th e r.
T he e g g s a n d la r v a e w h ich a r e n o t h ib e r n a tin g c o n tin u e to d e ­
v e lo p e v e n a t low t e m p e r a t u r e s to r e a c h m a tu r ity .

In th e p u p a l

c o n d itio n d e v e lo p m e n t w ould n o t p r o c e e d u n le s s th e w e a th e r
h a s s u f f ic ie n tly w a rm e d up.

T he e g g s a n d s u b s e q u e n t la r v a e

f r o m th e m w ould be e x p o se d to m o r e fa v o u ra b le c o n d itio n s.
It i s i n te r e s tin g to c o m p a re th e s e d a ta w ith th o s e of th e
c o d lin g m o th g iv e n by S h e lfo rd (23).

He c a lc u la te d 5 0 .1

o

and

5 1 .4 ° F . a s th e th r e s h o ld of d e v e lo p m e n t f o r r e la tiv e h u m id i­
t i e s of 70-97% a n d 50-60% r e s p e c tiv e ly .

T h e s e f ig u r e s a r e

p r a c t i c a l l y of th e s a m e o r d e r a s th o s e f o r th e o r ie n ta l f r u i t
m o th r e p o r t e d a b o v e ; th a t is th e th e o r e ti c a l th r e s h o ld of d e v e l­
o p m e n t is lo w e r in h ig h h u m id ity e x p e r im e n ts a s c o m p a re d to
th a t in th e low h u m id ity o n e s .

T he d iffe re n c e b e tw e e n th e v a l­

u e s a t h ig h a n d low h u m id itie s is m o r e in th e c a s e of th e o r i ­
e n ta l f r u i t m o th , sho w in g th a t th is s p e c ie s p r e f e r s m o r e m o is t
c o n d itio n s f o r i ts p u p a l d e v e lo p m e n t th a n d o e s th e co d lin g m o th .

(iii) O p tim u m a n d u p p e r v ita l l i m i t s :

T h e in d ic e s of d e v e lo p ­

m e n t ( F ig u r e s 8 -1 0 ) show u n ifo rm a c c e le r a tio n up to a te m p e r a tu r e

of 75

o

F.

A bove th is th e y d e fle c t to w a rd s th e r ig h t show ing

th a t th e r a t e of d e v e lo p m e n t s lo w s , dow n above 7 5° F .

T he

d e c lin e is l e s s s te e p u n d e r 100% r e la tiv e h u m id ity th a n u n d e r
35% r e la tiv e h u m id ity .

T h is d e c lin e i s m o r e th a n th a t f o r th e

l a r v a e , show ing th a t h ig h e r te m p e r a t u r e s a r e c o m p a ra tiv e ly
m o r e d e tr im e n ta l f o r th e p u p ae th a n f o r th e la r v a e .
T he e ffe c t of low te m p e r a t u r e s on co co o n in g la r v a e w as
n o t d e te r m in e d a s th e y a r e e x p e c te d to t o le r a t e f a i r l y low te m ­
p e r a t u r e s p re v a ilin g in te m p e r a te re g io n s .

T h is w ill n o t be

m a t e r i a l l y d if f e r e n t f r o m o th e r in s e c ts p a r t i c u l a r l y f r o m the
co d lin g m o th .

A c c o rd in g to N e w c o m e r a n d W hitcom b (19),

A w in te r te m p e r a t u r e of - 2 5 ° F . o r c o ld e r m a y
k ill a l l th e c o d lin g m o th la r v a e ab o v e snow lin e , a te m ­
p e r a t u r e of -2 0 to 25 F . m a y k ill 80 to 90 p e r c e n t of
th e l a r v a e , a te m p e r a tu r e of -1 5 to -2 0 F . m a y k ill
70 to 80 p e r c e n t, w h ile a t e m p e r a t u r e of o nly -7 o r
- 8 F . k ills o nly a b o u t fo u r p e r c e n t of th e w in te rin g
la rv a e .

(b) E ffe c t of h u m id ity on d e v e lo p m e n t

T he d a ta in l i t e r a t u r e on th is a s p e c t is e x tr e m e ly m e a g r e .
In f a c t, i t is s u r p r i s i n g how th is im p o r ta n t a s p e c t of th e in flu ­
e n c e of h u m id ity on p u p a l d e v e lo p m e n t r e c e iv e d so little a tte n ­
tio n f r o m w o r k e r s in th e p a s t.

A s th e p u p a l s ta g e of the

o r i e n t a l f r u i t m o th is g e n e r a lly p a s s e d o u ts id e th e g r e e n t is s u e s
i t m a y be c o n s id e r e d lik e ly th a t c o m p a r a tiv e ly d r i e r c o n d itio n s
sh o u ld s u it th e p u p ae b e t t e r .
th is i s n o t th e c a s e .
m o r e u s e fu l.

P r e s e n t in v e s tig a tio n s show th a t

S a tu r a te d a tm o s p h e r e w a s fo u n d to be

It m a y b e , th a t in n a tu r e h ig h h u m id ity is m a in ­

ta in e d n e a r th e s u r f a c e of th e s o il by e v a p o ra tio n of m o is tu r e
f r o m th e s o il a n d on a c c o u n t of th e p r e s e n c e of lu x u r ia n t g ro w th
of g r a s s e s a n d w e e d s a ro u n d th e t r e e s w h e re m o s t of th e pupae
a r e fo u n d .

F r e q u e n t r a i n s d u rin g th e a c tiv e s e a s o n w ould a ls o

h e lp in k e e p in g th e h u m id ity h ig h .
In th e s e e x p e r im e n ts th e p u p a l p e r io d w a s found to be
s h o r t e s t u n d e r 100% a n d lo n g e s t u n d e r 35% r e la tiv e h u m id ity .
It w a s 19 d a y s , 1 4 .3 d a y s , 12 d a y s a n d 1 1 .0 d a y s u n d e r 100%
r e l a ti v e h u m id ity a s c o m p a re d to 2 4 .5 d a y s , 1 7 .3 d a y s , 1 4 .2
a n d 1 2 .5 d a y s , u n d e r 35% r e la tiv e h u m id ity , a t c o n s ta n t te m ­
p e r a t u r e s of 6 5 °, 7 5 °, 8 5 ° a n d 9 5 ° F . , r e s p e c tiv e ly .

A low

r e l a ti v e h u m id ity w a s e x tr e m e ly d e tr im e n ta l to pupae k e p t a t
85

o

.
°
F . w hen t h e i r egg a n d l a r v a l p e rio d s h a d b e e n a t 75 o r

6 5 ° F . , a s v e r y few m o th s e m e r g e d f r o m a la r g e n u m b e r of
pupae.

T he m o th s e m e rg in g u n d e r 100% r e la tiv e h u m id ity a t

9 5 ° F . w e re d e fo rm e d a n d s h o r t liv e d ; th o s e e m e rg in g u n d e r

59
70%

r e l a ti v e

h u m id ity w e re

w e ll fo r m e d , a c tiv e a n d liv e d

lo n g e r .

(c) E ffe c t of te m p e r a tu r e a n d h u m id ity on v ia b ility

T h e v ia b ility of th e p u p ae of th e o r ie n ta l f r u i t m o th is
in flu e n c e d b o th by t e m p e r a t u r e a n d r e la tiv e h u m id ity .

A t the

m e d iu m ra n g e of t e m p e r a t u r e s th e e ffe c t of h u m id ity is w e ll
m a rk e d .

T he d a ta is p r e s e n t e d in T a b le V I a n d show n in F i g ­

u r e s 1 1 -1 3 .

A t c o n s ta n t t e m p e r a t u r e s of 6 5 °, 7 5 °, 85° a n d

9 5 ° F . , th e v ia b ility w a s 4 1 .8 % , 7 1 .8 % , 68.36% a n d 14.0%
u n d e r a r e l a ti v e h u m id ity of 100% ; 2 4 .5 % , 5 0 .4 % , 54.55% a n d
25% u n d e r a r e la tiv e h u m id ity of 70% ; 8 .4 % , 4 0 .6 % , 31.97%
a n d 1 1 .3 % u n d e r a r e la tiv e h u m id ity of35% , r e s p e c tiv e ly .

On

th e w hole v ia b ility w a s m a x im u m a t 75° F . u n d e r d if fe re n t
r e l a ti v e h u m id itie s a s c o m p a re d to o th e r t e m p e r a t u r e s , w ith
th a t a t 8 5 ° F .

c o m in g v e r y c lo s e to it.

t u r e s p u p a e e x p o s e d to 85

o

A t v a r ia b le t e m p e r a -

F . b u t f o r m e d f r o m la r v a e r e a r e d

a t 6 5 ° F . h a d a v ia b ility of 4 5 .8 3 % , 3 6 .7 % a n d 1 .2 % u n d e r a
r e la tiv e h u m id ity of 100% , 70% a n d 35% r e s p e c tiv e ly .
o th e r h a n d p u p ae f o r m e d f r o m l a r v a e r e a r e d a t 85

o

On the
,

F . and

k e p t a t 6 5 ° F . h a d a v ia b ility of 4 5 .8 6 % u n d e r a re la tiv e

60
h u m id ity of 100% , 2 6 .2 5 % tin d e r 70% h u m id ity a n d 1 5 .1 % u n d e r
th e low h u m id ity of 35% .

T he v ia b ility w a s a lw a y s h ig h e s t

u n d e r s a t u r a t e d a tm o s p h e r e a t a l l th e c o m b in a tio n s of t e m p e r ­
a tu re s trie d .

U s u a lly i t w a s a b o u t one a n d a h a lf tim e s th e

f ig u r e f o r 70% r e la tiv e h u m id ity .

T he p e r c e n t v ia b ility w as

g e n e r a lly l e a s t u n d e r 35% r e la tiv e h u m id ity ; u n d e r one s e t of
te m p e ra tu re s it w as even z e ro .
T h e v ia b ility of p u p a e e x p o s e d to 65° F . , an d 35% r e l ­
a tiv e h u m id ity b u t f o r m e d f r o m l a r v a e r e a r e d a t 8 5° F . w as
a lm o s t d o u b le of th o s e w h ich h a d th e e n tir e life a t 65° F .

T h is

m e a n s th a t a g r e a t e r n u m b e r of la r v a e w h ic h m a tu r e d u n d e r
h ig h e r t e m p e r a t u r e s w e r e a b le to c o m p le te t h e i r life s u c c e s s ­
fu lly a t low t e m p e r a t u r e s c o m b in e d w ith low h u m id ity (to w h ich
th e p u p a e w e re e x p o sed ) a s c o m p a r e d to th o s e w h ich w e re
r e a r e d a t low t e m p e r a t u r e s a n d th e p u p a e e x p o se d to low te m ­
p e r a t u r e a n d low h u m id ity .
A v ia b ility of 15. 1% u n d e r 35% r e la tiv e h u m id ity i s a
l i t t l e l e s s th a n o n e - th ir d of 4 5 .8 6 % v ia b ility u n d e r s a tu r a te d
c o n d itio n s a t t e m p e r a t u r e s of 65
th e l a r v a l s ta g e .

o

F . f o r p u p ae a n d 85

T h is is r a t h e r s ig n ific a n t.

o

F . fo r

In a r e a s of low

h u m id ity in la te s u m m e r a n d e a r l y f a ll a l e s s e r n u m b e r of

4

61
m o th s w ould e m e r g e .

C o n se q u e n tly th e d a m a g e to f r u i t in

th o s e a r e a s is lik e ly to be l e s s .

On th e o th e r h a n d p la c e s

w h ic h a r e m o r e h u m id a t th a t tim e m a y h a v e l a r g e r e m e rg e n c e
of m o th s a n d th e r e is a g r e a t e r lik e lih o o d of d a m a g e to f r u i t s
f r o m th e la te b ro o d s of l a r v a e .

4.

L a r v a l D ia p a u se

T h e l a r v a e of th e o r ie n ta l f r u i t m o th lik e th o se of s e v ­
e r a l o th e r s p e c ie s go in to h ib e rn a tio n , i . e . , e n te r d ia p a u se in
la te s u m m e r a n d f a ll to tid e o v e r u n fa v o ra b le w e a th e r a n d food
c o n d itio n s .

T he la r v a e s p in th ic k s ilk e n c o c o o n s an d th e n r e s t

in s id e th e m f o r a n e x te n d e d le n g th of p e rio d b e fo re t r a n s f o r m ­
in g in to p u p a e .

S e v e ra l w o r k e r s h a v e a tte m p te d to in v e s tig a te

th e c a u s e s w h ic h in itia te d ia p a u s e .

T h o se m a y be fa llin g t e m ­

p e r a t u r e s in f a l l , so m e ch an g e in th e q u a lity a n d w a te r c o n te n t
of fo o d , r e la tiv e h u m id ity , p h o to p e rio d is m , h o r m o n e s o r so m e
in h e r e n t f a c t o r s .
D ic k so n (5).

T h e s e h a v e b e e n v e r y a b ly re v ie w e d by

A lth o u g h th e p r e s e n t in v e s tig a tio n w a s n o t d i­

r e c t e d to w a rd s fin d in g ou t th e f a c t o r s r e s p o n s ib le f o r in d u cin g
d ia p a u s e s e v e r a l i n te r e s tin g f e a t u r e s h av e b e e n re v e a le d .

T he

r e s u l t s of th e s e o b s e r v a tio n s a r e g iv e n in T a b le s V II to IX.

T A B L E VII
P E R IO D O F D IA PAU SE P L U S P E R IO D O F P U P A T IO N F O R SHORT C Y C L E LA R V A E* O F
G R A PH O LITH A M O LE ST A U N D ER D IF F E R E N T CONDITIONS
T e m p e r a tu r e
° F.

P e r io d
at

Eggs
and
L a rv a e
R e are d
at

R e la tiv e H u m id ity
70%

100%
A v e r­
ag e
P e rio d

N o. of
O b ser­
v a tio n s

35%

A v e r­
ag e
P e rio d

N o. of
O b ser­
v a tio n s

A v e r­
ag e
P e rio d

N il

N il

N il

No. of
O b ser­
v a tio n s

65

65

39

8

75

75

46. 7

8

49

15

85

85

N il

N il

35

2

4 4 .5

4

85

75

3 4 .3

24

3 4 .8

42

N il

N il

85

65

N il

N il

3 4 .4

20

N il

N il

65

85

N il

N il

N il

N il

N il

N il

65

75

N il

N il

N il

N il

N il

N il

* T o ta l p e r io d e x te n d in g f r o m th ir ty - o n e to s ix ty d a y s

53

N il
18

T A B L E V in
P E R IO D O F D IA PA U SE P L U S P E R IO D O F P U P A T IO N F O R LONG C Y C L E LA RV A E* O F
G R A PH O LITH A M O LESTA UN D ER D IF F E R E N T CONDITIONS
T e m p e r a tu r e
° F.

R e la tiv e H u m id ity
70%

100%

H ib e r ­
n a tin g
L arv a e
an d
Pupae
K ept
at

Eggs
and
L a rv a e
R e are d
at

•
A v­
e r­
ag e

65

65

75
85
85
85
65

75
85
75
65
85

1 3 2 .5

65

75

162

139

M ax ­ M in­
i­
i­
m um m um

241

N o.
of
O bse rvatio n s

75

72

62

140

184

124

179

113

87. 7 126

A v ­ M ax­ M in l—
e r­
i­
ag e m u m m u m

la r v a e

t r a n s fe r r e d , to

room

N o.
of
„
O bse rvatio n s

110

137

46

140
7 6 .6
N one
N one
N one
1 0 9 .5

170
32**
109
104
63
15
e n te r in g d ia p a u se
e n te r in g d ia p a u se
e n te r in g d ia p a u se
1-©
76
4

18

130

160

88

110

* Total period more than sixty days
♦ ♦ H ib e r n a tin g

35%

tem .nera.ture

and

100<&

8

17

A v - M a x - M in ­
e rii—
ag e m u m m u m

N o.
of
O bse r—
yatio n s

No m o th e m e r g e d f r o m
h ib e rn a tin g la r v a e
74

85

67

8

No m o th e m e r g e d f r o m
la r v a e e n te r in g d ia p a u se
No m o th e m e r g e d f r o m
la r v a e e n te r in g d ia p a u se

T A B L E IX
P E R C E N T E M E R G E N C E O F MOTHS O F G R A PH O LIT H A M O LESTA
U N D ER D IF F E R E N T CONDITIONS
T e m p e r a tu r e
° F.

M e d iu m C y cle

L o n g C y cle

% R e la tiv e H u m id ity

% R e la tiv e H u m id ity

% R e la tiv e H u m id ity

100

70

100

35

100

70

35

2 8 .5 7
4 7 .1 4
100
8 1 .2 5
100
6 2 .3
47. 0

5 8 .3 3
6 0 .0
9 7 .9
6 9 .1
5 4 .5
9 0 .5
7 5 .0

0 .0
1 7 .3
4 .2 6
0 .0
0 .0
0 .0
0 .0

6 4 .3
50. 0

4 1 .6 7
20. 0
0 .0
0 .0
0 .0
9 .5
2 5 .0

35

7 .1 3
2 .8 6
1 8 .7 5
0 .0
0 .0
0 .0

0 .0
2 0 .0
2. 1
3 0 .9
4 5 .5
0 .0
0 .0

0 .0
0 .0
3 7 .7
5 3 .0

7 .7
o
•
o

100
7 5 .0
9 5 .7 4
0 .0
100
100
100

70

o
•
o

65
75
85
75
65
85
75

S h o rt C y cle

o
•
o

65
75
85
85
85
65
65

Eggs
and
L arv a e
R e are d
at

o
•
o

H ib e r ­
n a tin g
L arv a e
a n d /o r
Pupae
K ept
at

P e r c e n ta g e of M o th s E m e rg in g f r o m L a r v a e
in

0 .0
0 .0
0 .0
0 .0

O'

65
T he p e rio d of d ia p a u s e c a n be d iv id e d in to tw o c a te g o r ­
i e s , s h o r t d ia p a u s e f o r a p e r io d of 3 1 -6 0 d a y s a n d long d ia ­
p a u s e f o r a d u r a tio n of o v e r 60 d a y s .

L a r v a e b e lo n g in g to

b o th of th e s e c a te g o r ie s w e r e fo u n d a m o n g th o se r e a r e d a t
v a r io u s c o n s ta n t t e m p e r a t u r e s a n d r e la tiv e h u m id itie s .

(a) S h o rt D ia p a u se

(i) E f f e c t of t e m p e r a t u r e :

L a r v a e e n te r in g s h o r t d ia p a u se w e re

fo u n d a t c o n s ta n t t e m p e r a t u r e s of 6 5 °, 7 5 ° a n d 85° F . a n d a t
so m e of th e v a r ia b le t e m p e r a t u r e s (T a b le VII).

T he a v e ra g e

d u r a tio n in c lu d in g p u p a l p e r io d w a s 39 d a y s a t 65° F . , 46. 7
d a y s a t 75
85

o

o

.

F . u n d e r 100% r e la tiv e h u m id ity a n d 35 d a y s a t

F . u n d e r 70% r e la tiv e h u m id ity .

T he m a x im u m a v e ra g e

w a s of 53 d a y s a t 7 5 ° F . a n d 4 4 .5 d a y s a t 85° F .

T he l a r g ­

e s t n u m b e r of l a r v a e in th is c a te g o r y w a s fo u n d a m o n g th o se
r e a r e d a t 75

o

F . a n d th e n t r a n s f e r r e d to 85

c o c o o n p e r io d .

o

F . d u rin g th e

N e x t to th is w a s a c o n s ta n t te m p e r a tu r e of 75

F . p r e v a ilin g in th e egg a n d l a r v a l s ta g e s , a s w e ll a s a f t e r
th e y h a d sp u n c o c o o n s.

A l a r v a l te m p e r a tu r e of 65° F . f o l­

lo w ed b y 85° F . d u rin g th e c o co o n life w a s th ir d in h av in g
e

q u iiscen t l a r v a e .

L a r v a e r e a r e d a t h ig h te m p e r a t u r e s of 75

O

o

66
F . a n d 8 5 ° F . a n d th e n t r a n s f e r r e d to 65° F . did n o t e n te r
in to s h o r t d ia p a u s e , c h ie fly b e c a u s e th e y w en t in to long d ia ­
p au se.
T h is p e r io d of s h o r t d ia p a u s e a p p e a r s to be d if f e r e n t
f r o m th e p e rio d of q u ie s c e n c e w h ic h is in d u c e d by low te m ­
p e r a t u r e s an d e a s i l y te r m in a te d w hen th e m a t e r i a l is t r a n s ­
f e r r e d to a h ig h t e m p e r a t u r e a s it c a m e a b o u t e v e n a t o p tim u m
te m p e r a t u r e s .

In f a c t th e l a r g e s t n u m b e r a n d lo n g e s t p e rio d

of " s h o r t d ia p a u s e " w a s in th e c a s e of l a r v a e r e a r e d a t the
o p tim u m t e m p e r a t u r e of 75

o

F.

S om e e v e n h ib e r n a te d a t the

r e l a ti v e ly h ig h te m p e r a t u r e of 8 5 ° F .

It c o u ld n o t h a v e b e e n

th e r e s u l t of u n fa v o ra b le te m p e r a tu r e o r h u m id ity o r ev en food,
a s th e s a m e k in d of fo o d w a s g iv e n in a l l c a s e s .

It w ould not

be due to the e ffe c t of lig h t a s a l l th e m a t e r i a l w as r e a r e d in
d a r k n e s s e x c e p t f o r th e tim e of ta k in g d a ily o b s e r v a tio n s .

T h is

p h e n o m e n o n a p p e a r s to be b a s e d m o r e on g e n e tic a l f a c t o r s th a n
a n y th in g e ls e .

(ii) E f fe c t of h u m id ity :

C ocooning la r v a e w e re k e p t u n d e r r e l ­

a tiv e h u m id itie s of 100% , 70% a n d 35% a t v a rio u s te m p e r a tu r e s
a n d th e r e s u l t s a r e s u m m a r iz e d in T ab le VII.
h u m id ity on th is a s p e c t i s r a t h e r d is tin c t.

The e ffe c t of

A t a c o n sta n t

67
te m p e r a t u r e of 65° F . no l a r v a e n te r e d s h o r t d ia p a u se u n d e r
r e la tiv e h u m id itie s of 70% a n d 35% , w h e r e a s a few d id b eh av e
so u n d e r s a t u r a t e d a tm o s p h e r e .

A t 75° F . th e l a r g e s t n u m b e r

b e c a m e q u ie s c e n t w ith a n a v e r a g e p e r io d of 53 d a y s u n d e r 35%
r e la tiv e h u m id ity ; th e n u m b e r a n d p e rio d d e c r e a s in g w ith th e
r i s e of h u m id ity .

U n d e r 100% r e l a ti v e h u m id ity none e n te r e d

s h o r t d ia p a u s e a t 85
th e c o c o o n p e r io d .
d r i e r c o n d itio n s .
h e ld a t 85

o

o

F . p re v a ilin g in th e l a r v a l a s w e ll a s in

A few , h o w e v e r, w ent in to d ia p a u se u n d e r
A f a i r l y la r g e n u m b e r of cocooning la r v a e

F . w ith fe e d in g p e rio d a t 75

o

F . e n te r e d s h o r t

d ia p a u s e u n d e r m o r e m o is t c o n d itio n s , b u t fe w e r u n d e r 100%
r e la tiv e h u m id ity th a n u n d e r 70% .

A low h u m id ity of 35% un­

d e r th e s a m e c o n d itio n s w a s f a ta l a s ou t of 135 co co o n ed l a r v a e none e m e r g e d a s a m o th .

S e v e ra l c o co o n e d la r v a e a t 85

o

F . w ith g ro w in g p e rio d a t 65° e n te r e d q u ie s c e n c e u n d e r 70% .
r e la tiv e h u m id ity ; none e n te r e d d ia p a u s e u n d e r 100% re la tiv e
h u m id ity .

O v e r 98% d ie d w ith o u t e m e rg in g a s m o th s u n d e r

35% r e l a ti v e h u m id ity .

T he d u r a tio n of s h o r t d ia p a u se (fo r

34 d a y s o r so) of l a r v a e h e ld a t 8 5 ° F . w ith g ro w in g p e rio d
e it h e r a t 75° o r 6 5° w a s a lm o s t th e s a m e .

H o w ev e r, in the

l a t t e r c a s e (g ro w in g p e rio d a t 6 5° F . ) th e r e w e re no h ib e rn a tin g

l a r v a e u n d e r 100% r e la tiv e h u m id ity a s th ey a ll e m e r g e d a s
m o th s w ith in a r e a s o n a b le p e rio d .

U n d e r th e s e s e t of te m p e r ­

a tu r e c o n d itio n s t h e r e w a s a lm o s t c o m p le te m o r ta li t y of c o ­
c o o n ed l a r v a e a t 35% r e la tiv e h u m id ity .
F r o m th e ab o v e i t co u ld be i n f e r r e d th a t th is s p e c ie s
m a y o v e rc o m e u n fa v o ra b le c o n d itio n s b ro u g h t a b o u t b y low
h u m id ity by in d u c in g s h o r t d ia p a u se in th e p re p u p a l sta g e e v en
th o u g h th e p r e v a ilin g t e m p e r a tu r e i s o p tim u m ; u n le s s th e h u ­
m id ity i s so low a s to be f a ta l w hen p re v a ilin g o v e r a n e x te n d e d
p e rio d .

(b) L ong D ia p a u se

In th is c a te g o r y a r e in c lu d e d a l l th o s e l a r v a e in co co o n s
w h ic h e m e r g e d a s m o th s a f t e r a p e r io d of a t l e a s t s ix ty d a y s
in th e p r e s e n t in v e s tig a tio n .

It in c lu d e s th e su b s e q u e n t p u p a l

p e rio d a s the la r v a e w e re g e n e r a lly n o t d is tu r b e d w hile in c o ­
c o o n s.

Som e of th e p re v io u s w o r k e r s h a v e m e n tio n e d th e l a r ­

v a l p e rio d in c o co o n s e p a r a te ly f r o m th e p u p a l p e rio d e ith e r
b y d is tu r b in g th e l a r v a e o r by a lim ite d n u m b e r of o b s e rv a tio n s
on m a t e r i a l k e p t in p a r tly t r a n s p a r e n t c o rr u g a te d p a p e r.
w a s n o t c o n s id e r e d e s s e n t ia l in th e s e e x p e rim e n ts .

T h is

69
(i) E ffe c t of t e m p e r a t u r e :

T he c o co o n p e r io d of th e la r v a e of

o r i e n t a l f r u i t m o th u n d e r in s e c t a r y c o n d itio n s h a d b e e n d e t e r ­
m in e d b y s e v e r a l w o r k e r s a t v a r io u s p la c e s .

S te a r n s an d

P e t e r s o n (27) r e p o r te d th e c o m b in e d c o co o n a n d p u p a l p e r io d a s
v a ry in g f r o m 91 to 303 d a y s w ith a n a v e ra g e of 248 d a y s.
P e t e r s o n a n d H a e u s s le r (20) a t R iv e rto n , N ew J e r s e y found i t
to be 2 5 8 .8 5 d a y s in 1925 a n d 2 5 2 .4 0 d a y s in 1926, on a n a v ­
e ra g e .

T he m a x im u m f ig u r e s f o r th e c o rre s p o n d in g y e a r s w e re

306 d a y s a n d 307 d a y s , a n d th e m in im u m 131 d a y s a n d 176 d a y s.
Snapp a n d S w ingle (24) r e c o r d e d th e a v e r a g e h ib e rn a tio n p e rio d
in c lu d in g p u p a l s ta g e a s 2 0 8 .4 d a y s , 1 8 9 .3 d a y s a n d 1 8 2 .5 d a y s
f o r th e fifth , s ix th a n d se v e n th b ro o d r e s p e c tiv e ly .
im u m w a s 278 d a y s a n d a m in im u m of 135 d a y s .

T h e ir m a x ­
F r o m th e s e

d a ta i t is c l e a r th a t th e p e r io d of d ia p a u s e of th is m o th v a r i e s
c o n s id e r a b ly u n d e r d if f e r e n t c o n d itio n s a n d s e e m s to be in flu ­
e n c e d by te m p e r a tu r e .
T he d a ta on d ia p a u s e u n d e r v a rio u s c o n d itio n s s tu d ie d
d u rin g th e p r o g r e s s of th e p r e s e n t w o rk a r e g iv e n in T a b le s
V III a n d IX.

A n e x a m in a tio n of th e s e ta b le s show s th a t th e

l a r v a e w e n t in to d ia p a u s e a t c o n s ta n t te m p e r a t u r e s of 65

an d

7 5 ° F . ; a n d u n d e r v a r ia b le t e m p e r a t u r e s w hen co co o n s fo r m e d

70
by la r v a e , g ro w n a t 75

a n d 85

F . w e re t r a n s f e r r e d to 65° F .

T h e fe e d in g la r v a e a s w e ll a s th e c o co o n e d o n e s a n d p u p ae w e re
k e p t in to ta l d a r k n e s s e x c e p t f o r s h o r t d u ra tio n s w hen th e y w e re
ta k e n o u t f o r e x a m in a tio n o r th e d o o rs of the in c u b a to rs an d
r e f r i g e r a t o r s w e re o p e n ed f o r o th e r o b s e rv a tio n s .

A t a con­

s ta n t t e m p e r a t u r e of 6 5° F . , 6 4 .3 % , 41.67% a n d 0 .0 % of the
l a r v a e s u c c e s s f u lly c o m p le te d t h e i r d ia p a u se u n d e r r e la tiv e
h u m id itie s of 100, 70 a n d 35% .

A t 75° F . th e c o rre s p o n d in g

f ig u r e s w e re 50% , 20% , a n d 7 . 7 % .
a t 6 5 ° F . , 3 7 .7 % ; 9 .5 % a n d 0 .0 %

U n d e r v a r ia b le te m p e r a tu r e s
la r v a e s u c c e s s f u lly c o m p le te d

h ib e r n a tio n w h en th e y h a d b e e n g ro w n a t 85° F . a s c o m p a re d
to 53% , 25% a n d 0 . 0 % w h en r e a r e d a t 7 5 ° F . u n d e r r e la tiv e
h u m id itie s of 100, 70 a n d 35% r e s p e c tiv e ly .
T he m a x im u m d u r a tio n of d ia p a u s e in c lu d in g th e pu p al
p e r io d w a s 241 d a y s a t 6 5° F .
days a t 65° F .

( la r v a e g ro w n a t 6 5 ° F . ) , 184

( la r v a e r e a r e d a t 8 5 ° F . ) , 162 d a y s a t 65

( la r v a e r e a r e d a t 7 5° F . ) a n d 126 d a y s a t 75° F .
a t 75° F . ) .

F.

( la rv a e r e a r e d

N one of th e l a r v a e e n te r e d d ia p a u se w hen k e p t a t

8 5 ° F . w h e th e r th e y w e re f e d a t 8 5 °, 7 5 ° o r 65
s im u la te s s p rin g a n d m id s u m m e r c o n d itio n s.

F.

T h is

T he p e r io d of

tw o m o n th s ' d ia p a u s e a t 7 9 ° F . m e n tio n e d by D ic k so n (5) a p p e a rs

71
to b e lo n g to th e c a te g o r y of " s h o r t d ia p a u s e . "

T he r e la tiv e

in flu e n c e of t e m p e r a t u r e s p r e v a ilin g d u rin g th e fe e d in g p e rio d
a n d th e c o co o n p e r io d is q u ite c l e a r f r o m th e d a ta g iv e n a b o v e .
E x c e p t f o r th o s e l a r v a e k e p t p e rm a n e n tly a t 65° F . , th e h ig h e r
the t e m p e r a t u r e f r o m w h ic h th e y w e re t r a n s f e r r e d to 65° F . ,
th e lo n g e r th e d ia p a u s e .
v a tio n s in o r c h a r d s .

T h is is in a g r e e m e n t w ith th e o b s e r ­

L a r v a e h ib e rn a tin g e a r l y in f a ll o r s u m ­

m e r w h en th e t e m p e r a t u r e s a r e h ig h h a v e a lo n g e r d ia p a u se
th a n th o s e h ib e r n a tin g l a t e r in th e s e a s o n .
D ic k so n (5) s tu d ie d so m e of th e f a c t o r s g o v e rn in g th e
in d u c tio n of d ia p a u s e in th e o r ie n ta l f r u i t m o th .

He p o s tu la te d

th a t d ia p a u s e in th e l a r v a e of th is m o th 'is in d u c e d by a h o r ­
m o n e o r h o r m o n e - lik e s u b s ta n c e th a t is p ro d u c e d by th e la r v a
d u rin g th e l a r v a l fe e d in g p e rio d .

He f u r t h e r c o n c lu d e d th a t

th is h o rm o n e is p ro d u c e d by a tw o -p h a s e r e a c tio n , w h ich r e ­
q u ir e d d a r k n e s s f o r on e p h a s e a n d lig h t f o r th e o th e r a n d th a t
th e in d u c tio n of d ia p a u s e is c o n tr o lle d by te m p e r a tu r e a n d d a ily
e x p o s u re to lig h t d u rin g th e l a r v a l fe e d in g p e rio d .

A c c o rd in g

to h im v e r y few la r v a e g ro w n in th e a b s e n c e of lig h t e n te re d
d ia p a u s e .

T he p r e s e n t o b s e r v a tio n s do n o t s u p p o rt h is th e o ry ,

p a r t i c u l a r l y w ith r e g a r d to th e e ffe c t of lig h t.

A s w ill be s e e n

72
f r o m T a b le V III a n d r e p o r te d ab o v e 64.3% la r v a e s u c c e s s f u lly
c o m p le te d d ia p a u s e a n d e m e r g e d a s m o th s , e v en though th e y
w e re g ro w n in to ta l d a r k n e s s a t 65° F . an d 50% w hen r e a r e d
a t 7 5 ° F . a n d k e p t a t th e s a m e te m p e r a tu r e of 7 5 °.
r e a r e d a t 75

a n d 85

a n d k e p t a t 65

L a rv a e

F . a ls o w ent in to d ia ­

p a u s e in f a i r l y la r g e n u m b e r s , p a r t i c u l a r l y u n d e r 100% r e l a ­
tiv e h u m id ity .

T h e a c tu a l n u m b e r of la r v a e w hich w en t into

d ia p a u s e m u s t be m u c h h ig h e r th a n th e n u m b e r of m o th s e m e r g ­
ing f r o m th e m a s th e r e w ould n a tu r a lly be c o n s id e ra b le m o r ­
ta l i ty in th e h ib e rn a tin g s to c k .
T he r e a l c a u s e w h ich m a y in itia te d ia p a u se in th e o r i ­
e n ta l f r u i t m o th la r v a e a p p e a r s to be in h e r e n t an d m a y to som e
e x te n t be g o v e rn e d by th e n a tu r e a n d q u a lity of food on w hich
th e l a r v a e a r e fe d .

D ic k so n u s e d s m a ll im m a tu r e a p p le s to

fe e d th e l a r v a e , w h e r e a s , in th e p r e s e n t in v e s tig a tio n th e y w e re
fe d on a lm o s t m a tu r e a p p le s p ic k e d up in A u g u st a n d s to r e d a t
a b o u t 5 0 ° F . u n til n e e d e d .

T h is d iffe re n c e in food in th e two

in v e s tig a tio n s , m a y to so m e e x te n t be re s p o n s ib le f o r so m e of
th e c o n flic tin g r e s u l t s o b ta in e d .

L a r v a e r e a r e d d u rin g A p ril,

M ay a n d J u n e , 1951, on th e s a m e k ind of a p p le s s to r e d a t about
50° F .

d id n o t e n te r d ia p a u se e x c e p t v e r y few in d iv id u a ls .

73
I s e ly (17) c o u ld n o t fin d a n y r e la tio n s h ip b e tw e e n th e t r a n s f o r ­
m a tio n of th e la r v a e of c o d lin g m o th , C a rp o c a p s a p o m o n e lla ,
a n d th e r e la tiv e r ip e n e s s of th e f r u i t on w hich th e y w e re fe d .

(ii) E ffe c t of h u m id ity :

T he r e la tiv e h u m id ity to w h ich the

h ib e r n a tin g l a r v a e a r e e x p o se d s e e m s to hav e a g r e a t in flu e n ce
on th e e x te n t a n d s u c c e s s f u l c o m p le tio n of d ia p a u s e .

T he a c ­

tu a l n u m b e r of la r v a e going in to d ia p a u se w as not d e te rm in e d
in th e s e e x p e r im e n ts a s th e y w e re n o t d is tu r b e d in th e cocoons
b u t th e p r o p o r tio n is b e lie v e d to be f a i r l y h ig h .

S q u ire (25)

r e p o r t e d th a t th e d ia p a u s e in th e la r v a e of p in k b o llw o rm ,
P e c tin o p h o r a g o s s y p ie lla (S a u n d .) d e p e n d s upon the m o is tu r e
c o n te n t of th e s e e d s in w h ic h th e y fe e d .

hi th e c a s e of th e

o r i e n t a l f r u i t m o th th e q u e s tio n of w a te r c o n te n t of food is r e l ­
a tiv e ly u n im p o rta n t.

A n e x a m in a tio n of T a b le s V III an d IX

sh o w s th a t r e la tiv e h u m id ity a c t s m o r e on th e p re p u p a l an d
p u p a l s ta g e s .

N one of th e l a r v a e in d ia p a u s e k e p t u n d e r 35%

h u m id ity a t a n y t e m p e r a t u r e w ith th e e x c e p tio n of th o se a t 75
F.

e m e r g e d a s m o th s .

o

A t 7 5 ° F . i t w as o nly 7 .7 % e m e rg e n c e .

T he h ib e r n a tio n w a s m o s t s u c c e s s f u l u n d e r 100% r e la tiv e h u ­
m id ity a n d to a n a p p re c ia b le e x te n t u n d e r 70% r e la tiv e h u m id ­
ity .

5.

E m e r g e n c e of M o th s U n d e r D iffe re n t C o n d itio n s

T h e p e r c e n ta g e of m o th s e m e rg in g f r o m la r v a e of d if­
f e r e n t c y c le s u n d e r v a r io u s c o n d itio n s is show n in T a b le IX.
T he l a r v a of th e o r ie n ta l f r u i t m o th a c c o rd in g to the p r e s e n t
in v e s tig a tio n c a n be d iv id e d in to th e fo llo w in g c a te g o r ie s :

(a) S h o rt c y c le l a r v a e :

T h o se la r v a e w h ich h a d th e p re p u p a l

p lu s p u p a l p e rio d l e s s th a n th irty - d a y s u n d e r a n y s e t of co n ­
d itio n s a r e c a lle d s h o r t c y c le o n e s .

T h ey p u p a te d so o n a f t e r

sp in n in g c o c o o n s a n d e m e r g e d a s m o th s .

(b) M e d iu m c y c le l a r v a e :

In c lu d e d in th is c la s s a r e th o se l a r ­

v a e w h ich h a d th e p re p u p a l p lu s p u p a l p e rio d v a ry in g f ro m th ir ty
one to s ix ty d a y s .

A t th e en d of th is p e rio d th e y e m e rg e d a s

m o th s .

(c) L o n g c y c le l a r v a e :

T he long c y c le la r v a e w e re th o se w hich

e n te r e d in to a d ia p a u s e of o v e r s ix ty d a y s ir r e s p e c t i v e of te m ­
p e r a t u r e a n d h u m id ity .

A t th e en d of th is p e rio d th e y e m e rg e d

a s m o th s w ith o u t b e in g t r a n s f e r r e d to a n o th e r s e t of c o n d itio n s.
It m a y be n o te d h o w e v e r, th a t th e s e la r v a e r e p r e s e n t
o n ly th o s e w h ic h w e re a b le to c o m p le te t h e i r life c y cle

75
s u c c e s s £ u lly a n d f in a lly e m e r g e d a s m o th s .

T he a c tu a l n u m b e r

b e lo n g in g to e a c h c a te g o r y m u s t h av e b e e n l a r g e r , p a r t i c u l a r l y
u n d e r th e long c y c le c l a s s , of w h ich m a n y m ig h t h av e d ied in
th e c o c o o n s.
T h e d u ra tio n of p e rio d f o r th e v a rio u s c l a s s e s of la r v a e
is g iv e n in T a b le s V, V II a n d V III a n d e x p la in e d in e a r l i e r
c h a p te r s .

T he r e la tiv e p r o p o r tio n s of th o se w h ich c o m p le te d

t h e i r life c y c le s a s b a s e d on th e e m e rg e n c e of m o th s u n d e r
d if f e r e n t c o n d itio n s a r e g iv en in T a b le IX.

(i) E f fe c t of t e m p e r a t u r e ;

It m a y be s e e n f r o m T a b le IX th a t

a t a c o n s ta n t te m p e r a tu r e of 65° F . a n d 75° F . a ll k in d s of
la r v a e w e re fo u n d .

o
A t a c o n s ta n t te m p e r a tu r e of 85 , la rv a e

w e re m o s tly in s h o r t c y c le , so m e in m e d iu m b u t none in long
c y c le , w h e th e r th e la r v a e w e re fe d a t 85 , 7 5
f o r e th e y w e re e x p o se d to 85

F.

o r 65

F . be­

If th e la r v a e g ro w n a t

e ith e r 7 5 ° o r 8 5 ° F . w e re k e p t a t 65° F . d u rin g t h e i r cocoon
p e r io d th e y b e lo n g e d to th e c a te g o ry of s h o r t c y c le o r to th a t
of long c y c le la r v a e a s none e m e r g e d a s m o th s u n d e r th e m e ­
d iu m c y c le .

76
(ii) E f fe c t of h u m id ity :

T he e ffe c t of r e la tiv e h u m id ity on th is

a s p e c t i s w e ll m a r k e d .

A low h u m id ity of 35% , on th e w hole

w a s h ig h ly in ju r io u s to th e d e v e lo p m e n t an d v ia b ility of c o co o n ed
la rv a e .

T h e re w a s v e r y lit t le e m e rg e n c e in c a s e th e la r v a e

g ro w n a t 65° o r 75° w e re k e p t a t 85° F . u n d e r 35% h u m id ity .
T h is m e a n s th a t in a r e a s w h e re w ith th e r i s e of te m p e r a tu r e
in J u n e - J u ly t h e r e is a d ro p in r e la tiv e h u m id ity , th e c o co o n ed
l a r v a e w ill h av e v e r y little c h an c e to e m e r g e a s m o th s .
A t 65° F . a l l m o th s w e re f r o m s h o r t c y c le la r v a e u n d e r
35% r e l a ti v e h u m id ity , none w a s f r o m m e d iu m o r long c y c le ;
w h e r e a s u n d e r 100% r e la tiv e h u m id ity 2 8 .5 7 % w e re f r o m s h o r t
c y c le , 7 .1 3 f r o m m e d iu m a n d 6 4 .3 f r o m long c y cle la r v a e .

At

7 5 ° F . a n d 100 p e r c e n t r e la tiv e h u m id ity th e r e w e re 47. 14%,
2 .8 6 % a n d 50% m o th s f r o m s h o r t, m e d iu m an d long c y c le l a r ­
v a e , r e s p e c tiv e ly , a s c o m p a re d to 75% , 17.3% a n d 7.7% u n d e r
35 p e r c e n t h u m id ity ; 60% , 20% a n d 20% u n d e r 70 p e r c e n t
r e la tiv e h u m id ity , r e s p e c tiv e ly .

U n d e r th e v a r ia b le te m p e r a tu re

e x p e r im e n ts (e g g s a n d la r v a e g ro w n a t 75

a n d 85

a n d cocooned

l a r v a e k e p t a t 65°) m o th s w e re e it h e r f r o m s h o r t c y c le o r long
c y c le l a r v a e .

N one w e re f r o m m e d iu m c y c le l a r v a e .

t e m p e r a t u r e s (65

O

A t th e s e
Q - O

F . f o r c o co o n e d la r v a e a n d p u p a e, 85

or

75

F . f o r e g g s a n d g ro w in g la r v a e ) if th e h u m id ity w a s low

a l l m o th s w e re f r o m s h o r t c y c le l a r v a e , none f r o m th e long
c y c le o n e s .
65

If th e la r v a e w e re g ro w n a t 85° F . a n d k e p t a t

F . a n d 100 p e r c e n t r e la tiv e h u m id ity th e r e w e r e 6 2 .3 %

m o th s f r o m s h o r t c y cle a n d 37. 7% f r o m long c y c le la r v a e ;
u n d e r 70 p e r c e n t h u m id ity th e r a tio w a s 9 0 .5 : 9 .5 .
th e la r v a e w e re r e a r e d a t 75

o

In c a s e

F . a n d d u rin g t h e i r cocoon

p e rio d w e re e x p o se d to 65° F . th e r a t i o of s h o r t to long cy cle
w a s 47:53 u n d e r 100 p e r c e n t r e la tiv e h u m id ity , a s c o m p a re d
to th a t of 75:25 u n d e r 70 p e r c e n t h u m id ity .

U n d e r 35 p e r c e n t

r e la tiv e h u m id ity p r a c t ic a l l y 100 p e r c e n t e m e r g e d a s m o th s in
th e s h o r t c y c le s e r i e s a t m o s t of th e t e m p e r a t u r e s .
th e o n ly e x c e p tio n w a s a t 7 5° F .

c o n s ta n t.

In f a c t

G e n e ra lly th e r e

w a s a b o u t h a lf of th e e m e r g e n c e f r o m long c y c le s e r i e s if th e
r e la tiv e h u m id ity h a d b e e n 100% ; a b o u t o n e - th ir d if i t h a d b e en
70% ; a n d n il u n d e r 35% r e la tiv e h u m id ity (e x c e p t 7 .7 % a t 75°
F.).

T h is in d ic a te s th a t in a r e a s w h e re low r e la tiv e h u m id ity

p r e v a ils d u rin g la te s u m m e r a n d e a r l y f a ll th e o r ie n ta l f r u it
m o th h a s a s tr o n g te n d e n c y to e m e r g e a s m o th s a n d n o t go
in to h ib e rn a tio n .

U n d e r th e s e c o n d itio n s th e p e s t w ould r e ­

m a in a c tiv e f o r a lo n g e r p e rio d a n d c o n se q u e n tly s u ffe r f r o m

78
s u b s e q u e n t s e v e r e c o ld s p e l ls .

H ib e rn a tio n of th e co co o n ed

l a r v a e is a b s o lu te ly e s s e n t ia l f o r th e s u r v iv a l of th e o r ie n ta l
f r u i t m o th in te m p e r a te r e g io n s .

If th e c o n d itio n s a r e d r y

v e r y few la r v a e w ould e n te r d ia p a u s e o r c o m p le te it s u c c e s s ­
fu lly .

V e ry few m o th s w ould e m e r g e in th e fo llow ing s p rin g

on th e r e t u r n of fa v o u ra b le c o n d itio n s .

On th e o th e r h a n d , s u b ­

s ta n tia lly l a r g e r n u m b e r of la r v a e e n te r d ia p a u s e o r c o m p le te
i t s u c c e s s f u lly if th e r e la tiv e h u m id ity to w h ich th e y a r e e x ­
p o s e d is h ig h enough.

T h is e n s u r e s g r e a t e r s u r v iv a l of th is

s p e c ie s in re g io n s w h e re h ig h h u m id ity p r e v a i ls in la te s u m m e r
a n d f a ll.
T h u s th e p r e s e n t g e o g ra p h ic d is tr ib u tio n of th e o r ie n ta l
f r u i t m o th a p p e a r s to be la r g e ly g o v e rn e d by th e r e la tiv e h u ­
m id ity p re v a ilin g d u rin g J u ly to N o v e m b e r, th e p e rio d w hen
la r v a e e n te r d ia p a u s e .

In h u m id a r e a s th e p e s t is f a r m o re

s e r io u s th a n in th e d r i e r r e g io n s .

T h is d iffe re n c e is e x p la in e d

b y th e in flu e n c e of r e la tiv e h u m id ity on th e s u c c e s s f u l c o m ­
p le tio n of d ia p a u s e ; h ig h e r h u m id itie s fa v o u rin g i t a n d lo w e r
h u m id itie s a ffe c tin g i t a d v e r s e ly , by b re a k in g th e d e fe n se of
th is in s e c t a g a in s t u n fa v o u ra b le c o n d itio n s.

79
In th e c a s e of c o d lin g m o th , C a r p o c a p s a p o m o n e lla , h o t
a n d d r y c o n d itio n s a r e c o n s id e r e d m o r e fa v o u ra b le .

C u trig h t

(4) h a s r e p o r te d f r o m O hio th a t in h o t a n d d r y s e a s o n in ju r ie s
to a p p le by th e la r v a e of c o d lin g m o th a p p e a re d e a r l y a n d in ­
c r e a s e d r a p id ly w hile in a c o o l w et s e a s o n i t w as th e r e v e r s e .
T h e r e f o r e , b o th s p e c ie s a lth o u g h r e s e m b lin g e a c h o th e r in s e v ­
e r a l r e s p e c t s m a y n o t n e c e s s a r i l y be e q u a lly s e r io u s in the
s a m e re g io n .

If one is m o r e a b u n d a n t in a n a r e a o r in a p a r ­

t i c u l a r s e a s o n m o s t lik e ly th e o th e r one m a y no t be so , a n d
v ic e v e r s a .

V.

T H E F E C U N D IT Y O F G R A PH O LIT H A M O LE ST A
U N D ER D I F F E R E N T CONDITIONS

T h e f e c u n d ity of G. m o l e s t a u n d e r i n s e c t a r y an d n e a r
o r c h a r d c o n d itio n s h a d b e e n e x te n s iv e ly s tu d ie d in the p a s t by
sev eral w orkers.

S t e a r n s an d P e t e r s o n (27) g ot a n a v e r a g e of

7, 23 a n d 40 e g g s p e r f e m a le f o r the f i r s t , s e c o n d a n d t h i r d
b r o o d m o t h s in N ew J e r s e y .

In G e o r g ia Snapp a n d Swingle

(24) fo u n d t h a t the a v e r a g e n u m b e r of e g g s p e r f e m a le w as
1 1 .3 , 6 . 4 , * 1 6 .9» 3 0 .5 , 6 2 .9 , 5 0 .0 a n d 6 6 .5 e g g s; f o r the s p r in g ,
f i r s t , s e c o n d , t h i r d , f o u r t h , fifth a n d s ix th b r o o d s r e s p e c t i v e l y .
A ld e n a n d C l a r k e (2) r e p o r t e d a n a v e r a g e of 46. 09 e g g s p e r
f e m a le w ith a m a x i m u m of 221 e g g s a t T h o m a s to n , G e o r g ia .
H a ru k a w a (12) go t a n a v e r a g e of 2 1 .9 to 6 6 .2 e g g s p e r f e m a le
in d i f f e r e n t e x p e r i m e n t s in J a p a n .
D u s ta n (6) c a r r i e d o u t s o m e e x p e r i m e n t s on th e in flu ­
e n c e of t e m p e r a t u r e a n d m o i s t u r e on the a d u lts of o r i e n t a l
f r u i t m o th in T o r o n to , C a n a d a .

He found t h a t the f e m a l e s la id

9 8 % of th e d a ily t o ta l of e g g s d u r in g the la te a fte r n o o n , f r o m
t h r e e h o u r s b e f o r e to one h o u r a f t e r s u n s e t .

T he h o u r of m a x ­

i m u m d e p o s itio n w a s th a t s t a r t i n g tw o h o u r s b e fo re s u n s e t.

In

h i s e x p e r i m e n t s th e m o th s c o m p le te ly s to p p e d egg lay in g a s
long a s th e y w e r e in t o ta l d a r k n e s s .

A h m a d a n d G h u la m u lla h

(1) fo u n d n o r m a l o v ip o s itio n in s i m i l a r d a r k n e s s by the m o t h s
of th e s p o tte d b o llw o r m of c o tto n , E a r i a s f a b ia ( S to ll.) .

U nder

m o r e o r l e s s c o n tr o l le d t e m p e r a t u r e c o n d itio n s the d a ta f o r
s e l e c t e d m o th s g iv e n by D u s ta n (6) w e r e 4 e g g s , 135 e g g s ,
114 e g g s p e r f e m a le a t a t e m p e r a t u r e ra n g e of 9 4 .5 to 9 6 .3 °
F . , 8 8 . 8 to 9 0 . 8 ° F . a n d 7 9 .3 to 8 5 . 4 ° F . , r e s p e c t i v e l y .

He

d id n o t m e n t i o n th e n u m b e r of m o th s l i b e r a t e d in e a c h b a t t e r y
ja r.

T h is o n ly sh o w s t h a t s o m e m o th s did la y eg gs u n d e r

h ig h t e m p e r a t u r e s .

T he p r e - i m a g i n a l life h i s t o r y of th o se

m o th s h a d n o t b e e n g iven.

In a n o th e r s e t of e x p e r i m e n t s he

g o t a n a v e r a g e of 2 9 .3 e g g s p e r f e m a le , fe d on m o i s t u r e and
l i b e r a t e d in c a g e s h a v in g m o i s t s a n d a t the b o tto m , a s c o m ­
p a r e d 7 . 7 e g g s p e r f e m a le in the c a s e of unfed m o th s k e p t in
dry cages.

H igh h u m id ity a t the tim e of o v ip o s itio n i s th u s

m o r e c o n d u civ e f o r egg lay in g th a n low h u m id ity .

If th is is

t r u e the m o th s m a y n o t be a b le to la y t h e i r f u ll quota of eggs
on p l a n t s in a r e a s in w h ic h r e l a t i v e h u m id ity is low, p a r t i c u ­
l a r l y in the a f te r n o o n a n d ev en in g .

In the p r e s e n t in v e s tig a tio n m o th s e m e r g in g f r o m pu pae
k e p t u n d e r d i f f e r e n t c o n d itio n s w e r e l i b e r a t e d in s m a l l c a g e s
d e scrib e d e a rlie r.

In o r d e r to p r o v id e s u ita b le c o n d itio n s f o r

o v ip o s itio n a n a l m o s t c o n tin u o u s su p p ly of p e a c h s e e d lin g s w as
m a i n t a i n e d in the g r e e n h o u s e .

P e a c h s h o o ts w ith t h e i r lo w e r

e n d s i m m e r s e d in w a t e r in s m a l l b o t tl e s w e r e su p p lie d to the
m o th s f o r egg lay in g in s id e the c a g e s .
w a s p a r t l y f i ll e d w ith m o i s t s a n d .

T he b o tto m of the c a g e s

T he g l a s s b o ttle c o n ta in in g

p e a c h s h o o t w a s c o v e r e d w ith c lo th to p r e v e n t o v ip o s itio n on it.
In the c a s e of th is s p e c i e s it w a s found e x t r e m e l y d iffic u lt to
o b ta in e g g s f r o m in d iv id u a l p a i r s l i b e r a t e d in t h e s e c a g e s .

C on­

s e q u e n tly s e v e r a l p a i r s w e r e k e p t t o g e t h e r a t v a r i o u s t e m p e r ­
a tu re s.

M any t i m e s o nly a s m a l l n u m b e r of m a l e s a n d f e m a l e s

w ould e m e r g e f r o m the s a m e s to c k on one day.

In t h e s e c a s e s

m o th s e m e r g in g o v e r a p e r i o d of s e v e r a l d a y s w e r e k e p t t o ­
g e t h e r in the s a m e c a g e .

A s a r e s u l t of th is i t w a s n o t p o s ­

s ib le to d e t e r m i n e the p r e o v ip o s itio n ,

o v ip o s itio n a n d th e p o s t

o v ip o s itio n p e r i o d s f o r th e m o t h s o r th e lo n g e v ity of the two
sexes.

H o w e v e r a r e c o r d of th e n u m b e r of m a l e s a n d f e m a l e s ,

a d d e d o r dying e a c h day w a s m a i n t a i n e d .

T he m o th s w e r e fe d

on th in s u g a r s o lu tio n so a k e d in c o tto n w a d s.

83
T h e o b s e r v a t i o n s on the o v ip o s itio n of m o th s r e a r e d an d
k e p t a t c o n s ta n t t e m p e r a t u r e s a r e g iv e n in T a b le X.

T he p r e -

i m a g i n a l a s w e ll a s th e i m a g in a l life w a s a lw a y s in d a r k n e s s .

(i)

E f f e c t of t e m p e r a t u r e :

It w ill be s e e n (T a b le X) th a t g e n ­

e r a l l y the f e m a l e s l a id v e r y few e g g s .
w ith o u t la y in g a n y e g g s .

M an y of th e m died

W h e th e r i t w a s due to d a r k n e s s c an

n o t be s a i d d e fin ite ly a s the p r o v i s i o n of lig h t in s o m e c a s e s
d id n o t im p r o v e t h e i r r e c o r d of o v ip o s itio n .
e r a g e of 1 2 .7 e g g s p e r f e m a le w a s a t 75

o

The h ig h e s t a v -

F.

A t 85

o

F . the

a v e r a g e w a s 9 . 8 e g g s w hen th e p r e i m a g i n a l life h a d b e e n a t
85

o

F .,

1 1 .3 e g g s if the l a r v a e w e r e g ro w n a t 75

o

F . and

0 . 3 e g g s if th e g ro w in g p e r i o d of th e l a r v a e h a d b e e n a t 65°
F.
F.

If th e p r e i m a g i n a l life w a s a t 65
the a v e r a g e w a s 7 .4 6 e g g s .

of 6 5 ° F .

o

an d i m a g in a l life a t 75

U n d e r a c o n s ta n t t e m p e r a t u r e

th r o u g h o u t the e n t i r e life of m o th s the m a x im u m

a v e ra g e w as 0 .5 eggs.

T h e o p tim u m t e m p e r a t u r e f o r egg

la y in g w a s t h e r e f o r e 75° F .
c o c o o n s a t 65° F . ,

o

c o n s ta n t.

M o th s a t 65

F . from

b u t l a r v a e g ro w n a t 75° o r 85° F . la id

v e r y fe w e g g s , the m a x i m u m a v e r a g e w a s 4 . 3 .

T h is s e t is

s o m e w h a t s i m i l a r to th e m o th s f r o m o v e rw in te r in g m a t e r i a l .
T h e s p r i n g b r o o d m o th s a r e known to la y v e r y fe w e g g s.

TABLE X
T H E FE C U N D IT Y O F G R A PH O L IT HA M O L E ST A U N D E R D I F F E R E N T CONDITIONS
R e la tiv e H u m id ity a t W hich
P u p a e W e re K e p t

T e m p e ra tu re
° F.

65
75
85
85
65
85
65
75

65
75
85
85
65
85
65
65

65
75
85
65
85
75
75
65

A verage
No. of
Eggs per
F e m ale
0 .3
1 2 .7
6 .2
0 .3
1 1 .3
0 .2 5
7. 46

70%
No.
of
P a irs

26
48
40
20
28
42
12
13

A verage
No. o f
Eggs p e r
F em ale
0 .5
8 .7
9 .8
o
•
o

Pupae
K ept
at

100%

o
•
o

A d u lts
at

Eggs
and
L arvae
R eared
at

4 .3
3 .4
1 .0
—

35%

No° '
pa°.r s

24
20
38
20
16
28
24
—

A verage
No. of
Eggs p er
F e m ale

No.
of
P a irs

0 .0
8
6
26
2 .2
27
V e r y fe w m o th s
0
14
No m o th s e m e r g e d
0 .0
7
—

—

00

(ii) E f f e c t of h u m id i t y :

T h e e ffe c t of low h u m id ity d u r in g the

c o c o o n life on the fe c u n d ity of m o th s is w e ll p ro n o u n c e d a n d
is c l e a r l y sho w n by th e o b s e r v a t i o n s s u m m a r i z e d in T a b le X.
G e n e r a l l y m a x i m u m o v ip o s itio n w a s f r o m m a t e r i a l e x p o s e d to
100% r e l a t i v e h u m id ity .
m id ity .

T he s e c o n d b e s t w a s u n d e r 70% h u ­

M o th s e m e r g in g f r o m m a t e r i a l k e p t a t 35% h u m id ity

l a i d v e r y few e g g s a n d in s e v e r a l c a s e s d id n o t la y a n y e g g s.
A t s o m e s e t of t e m p e r a t u r e s no m o th c o uld e m e r g e f r o m pupae
k e p t a t the low h u m id ity t r i e d .

It is t h e r e f o r e ,

e v id e n t f r o m

t h e s e o b s e r v a t i o n s t h a t low h u m id ity d u r in g t h e i r c o co o n p e r i o d
i s i n ju r i o u s to th e fe c u n d ity of m o th s .
v a l life a t 65° F . ,
life a t 65° F .

7 5 ° F . a n d 8 5 ° F . w ith cocoon a n d a d u lt

d id n o t la y a n y e g g s if the r e l a t i v e h u m id ity

d u r in g the c o co o n p e r i o d w a s 35% .
th e re fo re ,

In f a c t m o th s w ith l a r ­

L o w r e l a t i v e h u m id ity ,

is n o t o n ly in ju r i o u s to the d e v e lo p m e n t of th is s p e ­

c i e s b u t is a l s o e q u a lly o r ev en m o r e h a r m f u l to the e g g -la y in g
c a p a c i ty of the m o th s .

(iii) E x p e r i m e n t s a t r o o m t e m p e r a t u r e :

In a d d itio n to e x p e r i ­

m e n t s a t c o n s ta n t t e m p e r a t u r e s an d h u m id i t ie s m o th s e m e r g in g
f r o m m a t e r i a l g ro w n a t a n o r d i n a r y r o o m t e m p e r a t u r e of 70-80
F . w e r e l i b e r a t e d in l a r g e r c a g e s of 10" x 10" x 8" s iz e , kept

86
o v e r m o i s t s a n d in e n a m e l t r a y s .
m o th s w e r e c o u n te d e v e r y day .
i s r e c o r d e d in T a b le XI.
M ay,
o n ly .

T he e g g s la id by th e s e
T he o v ip o s itio n of t h e s e m o th s

T w elv e p a i r s w h ic h e m e r g e d d u r in g

1950, f r o m o v e r w in t e r in g l a r v a e la id a to ta l of fiv e e g g s
D u rin g J u ly a n d 1-15 A u g u s t,

1950, m o th s e m e r g in g

f r o m l a r v a e c o lle c te d f r o m p e a c h s h o o ts in th e o r c h a r d la id
42. 0 a n d 48. 6 e g g s on a n a v e r a g e p e r f e m a le r e s p e c t iv e ly .
T h e h i g h e s t a v e r a g e of 7 4 .5 e g g s p e r f e m a le b a s e d on o b s e r v a ­
tio n s of 105 p a i r s r e a r e d on a p p le s w a s o b ta in e d d u rin g the
p e r i o d S e p te m b e r 24th to O c to b e r 15th,
two w e e k s of O c to b e r,
p e r fe m a le ,

1950.

D u rin g the l a s t

1950, the a v e r a g e d ro p p e d to 37 eggs

a lth o u g h th e l a r v a e in th is p e r i o d w e r e a ls o fe d

on th e s a m e v a r i e t y of a p p le s a s th o se of th e p r e v i o u s p e rio d .
D u r in g N o v e m b e r ,

1950, a n d J a n u a r y ,

and 9 .2 eggs p e r p a ir re s p e c tiv e ly .
a v e r a g e w a s lo w e s t, i . e . ,

1951, t h e r e w e r e 9 . 4
In F e b r u a r y ,

3 .3 e g g s p e r f e m a le .

1951, the
T h is m a y be

due to th e f a c t th a t the m o th s h a d e m e r g e d f r o m o v e rw in te r in g
m a te ria l.
A p ril,

T h e a v e r a g e i n c r e a s e d to 9 . 6 in M a r c h ,

5 7 .1 e g g s in M ay a n d 6 5 . 4 in Ju n e ,

9 .3 in

1951.

T he fo llow in g f a c t o r s m ig h t h a v e b e e n r e s p o n s i b l e f o r
in d u cin g g r e a t e r o v ip o s itio n u n d e r l a b o r a t o r y c o n ditio ns:

T A B L E XI
T H E F E C U N D IT Y O F G R A PH Q LIT H A M O LE ST A MOTHS
A T ROOM T E M P E R A T U R E (7 0 -8 0 ° F . )

P e rio d

No.
of
P a irs

T o ta l
No.
of
Eggs

A verage
No. of
Eggs
per
F e m ale

S o u rc e of
M a terial

M ay, 1950

12

5

0 .4

O v e r w in te r in g l a r v a e

J u ly , 1950

30

1260

42. 0

L a rv a e fro m peach
sh o o ts

A u g u s t (1 -1 5 ),
1950

24

1166

4 8 .6

L a rv a e fro m peach
s h o o ts

4 6 .6

L a r v a e r e a r e d on J o n ­
a th a n a p p le s s t o r e d a t
about 50° F .

A u g u s t (1 6 -3 1 ),
1950

35

1630

S e p tem b er
(1 -7 ), 1950

14

462

33

S a m e a s above

S e p tem b er
(8 -1 5 ), 1950

54

1885

35

S a m e a s above

S ep tem b er
(1 6 -3 0 ), 1950

50

2210

44

S a m e a s above

S e p t. 24 to
O c t. 15, 1950

105

7827

7 4 .5

S a m e a s above

O c to b e r
(1 6 -3 1 ), 1950

50

1847

3 7 .0

S a m e a s above

N o v e m b e r , 1950

16

150

9 .4

S a m e a s above

J a n u a r y , 1951

17

156

9 .2

S a m e a s above

F e b r u a r y , 1951

21

70

3 .3

S a m e a s above

M a r c h , 1951

44

424

9 .6

S a m e a s above

A p r i l , 1951

34

316

9 .3

S a m e a s above

M ay, 1951

40

2284

5 7 .1

S a m e a s above

Ju n e (1 -1 5 ),
1951

36

2355

6 5 .4

S a m e a s above

88
(a) E f f e c t of w ide f lu c tu a tio n in t e m p e r a t u r e .
(b) L a r g e s iz e of the c a g e s .
(c) M o re n u m b e r of m o th s in e a c h c a g e .
(d) P r e s e n c e of lig h t in the r o o m d u rin g the day.
(e) T he r e l a t i v e le n g th of d a y a n d n ig h t in d if f e r e n t m o n th s .
T h e r e w a s w ide f lu c tu a tio n in the a v e r a g e f o r d if f e r e n t
p e r i o d s d u r in g the y e a r e v e n in the l a b o r a t o r y w h e re c o n d itio n s
w e r e a l m o s t s i m i l a r th ro u g h o u t.

It is im p o s s i b l e to p o s tu la te

th e r e a l c a u s e o r c a u s e s w ith o u t f u r t h e r in v e s tig a tio n of th is
asp ect.

It m a y be t h a t s u c c e s s i v e g e n e r a t i o n s la y v a ry in g

n u m b e r of e g g s w h ic h m a y b e c o n tr o l le d (am ong o t h e r things)
by g e n e t ic a l f a c t o r s .

VI.

M E T E O R O L O G IC A L DATA AND IN C ID EN C E O F
T H E O R IE N T A L F R U IT M OTH

M e t e o r o l o g ic a l d a ta f o r the y e a r s 1948 to 1950 f o r t h r e e
p l a c e s r e p r e s e n t i n g in la n d p e a c h g ro w in g a r e a s of th e U n ited
S t a te s of A m e r i c a a r e g iv e n in T a b l e s X II-X IV , X V III-X X,
X X III-X X V a n d sh ow n g r a p h i c a l l y in F i g u r e s 14-3 1.
p lac es a re :

These

C o lu m b u s , Ohio (L a titu d e 3 9 °5 8 ' N. L o n g itu d e

8 3 ° W. E le v a tio n 724 fe e t); G r a n d J u n c tio n ,

C o lo ra d o (L a titu d e

39°06* N . L o n g itu d e 1 0 8°3 2’ W. E le v a tio n 4 ,8 4 9 fe e t); an d L a n ­
s in g , M ic h ig a n (L a titu d e 4 2 °4 7 ' N. L o n g itu d e 84°36* W. E l e v a ­
tio n 859 f e e t) .

T he d a ta f o r the abov e p l a c e s i s c o m p a r e d

w ith th o s e of P a r a c h i n a r (L a titu d e 3 3 . 8 ° N. L o n g itu d e 7 0 .1 °
E . E le v a t i o n 5 ,7 8 4 f e e t) , Q u e tta ( L a titu d e 3 0 . 3 ° N. L o n g itu d e
67° E . E le v a t i o n 5 ,5 0 8 fe e t) a n d P e s h a w a r (L a titu d e 34° N.
L o n g itu d e 7 1 . 5 ° E . E le v a tio n 1 ,1 4 9 f e e t) .

T h e s e a r e g iv e n

in T a b l e s XV to XVII, XXI, XXII, XXVI to XXVIII a n d i l l u s ­
t r a t e d b y g r a p h s in F i g u r e s 1 4 -3 1 .
It w ill be s e e n f r o m th e ab o v e m e n tio n e d t a b l e s and
f i g u r e s t h a t the m e a n m a x i m u m t e m p e r a t u r e f o r Ju n e to A u g u st,
1950, w a s 8 0 . 5 ° to 8 3 . 4 ° F . a t C o lu m b u s; 8 6 . 8 ° to 8 8 . 4

F.

90
T A B L E X II
M E T E O R O L O G IC A L DATA F O R COLUM BUS, OHIO
F O R T H E Y E A R 1950
T e m p e ra tu re ° F .
A verage
M o n th

R a in ­
f a ll
in
In ch es

% R e l­
a tiv e
H u m id ­
ity a t
7:30
a. m .

D a ily
M ax­
im u m

D a ily
M in ­
im u m

M onthly

Jan .

4 8 .8

32. 1

4 0 .4

74

6 .8 6

82

Feb.

41 • 1

2 6 .0

33. 6

65

3 .2 2

82

M ar.

4 6 .5

2 8 .5

3 7 .5

80

1.31

77

A pr.

5 5 .8

37. 1

4 6 .4

75

3 .8 0

75

M ay

7 4 .5

5 4 .3

6 4 .4

87

1 .1 5

82

Ju n e

8 0 .5

6 0 .2

7 0 .4

94

1 .9 5

83

J u ly

8 3 .4

6 4 .3

7 3 .9

89

2 .9 6

85

A ug.

8 1 .9

6 2 .3

72 .1

94

3 .5 2

85

Septv

7 4 .7

5 7 .3

6 6 .0

88

2 .3 1

90

O c t.

69. 6

5 0 .2

5 9 .9

83

1 .5 8

89

Nov.

4 5 .3

3 0 .9

3 8 .1

80

4 .9 2

84

D ec.

34

1 9 .4

2 6 .7

57

3 .0 4

84

H ig h e s t

91
T A B L E X III
M E T E O R O L O G IC A L DA TA F O R GRAND JU N C T IO N ,
COLORADO F O R T H E Y EA R 1950
T e m p e ra tu re

F.
R a in ­
f a ll

A verage
M onth

% R e l­
a tiv e
H u m id ­
ity a t
5:30
a. m .

D a ily
M ax­
im u m

D a ily
M in ­
im u m

M on th ly

Jan.

33. 6

12. 6

23. 1

48

1 .4 0

81

Feb.

4 4 .4

2 4 .2

34. 3

65

0 .4 7

75

M ar.

5 3 .0

2 9 .5

4 1 .3

68

0 .4 2

61

A pr.

66. 3

38. 9

52. 6

82

0 .5 4

50

M ay

72. 6

4 5 .5

59. 1

86

0 .4 6

47

Ju n e

8 6 .8

5 4 :7

7 0 .8

95

0 .0 1

30

J u ly

8 8 .4

6 1 .4

7 4 .9

97

1 .0 0

52

A ug .

8 8 .3

5 9 .1

73. 7

96

0 .2 1

40

S e p t.

7 8 .3

5 4 .0

6 6 .2

97

1 .0 5

57

O ct.

7 5 .7

4 5 .7

6 0 .7

83

T races

35

N ov.

5 3 .3

2 9 .8

41. 6

69

0 .3 2

56

D e c.

4 5 .6

25. 1

3 5 .4

53

0 .3 0

72

H ig h e s t

J " es

92
T A B L E XIV
M E T E O R O L O G IC A L DATA F O R LANSING, M ICHIGAN
F O R T H E Y EA R 1950
T e m p e ra tu re

F.
R a in ­
fall

A verage
M onth

% R e l­
a tiv e
H u m id ­
ity a t
7:30
a. m .

DailyM ax­
im u m

D a ily
M in ­
im u m

M onthly

Jan.

3 8 .9

2 0 .7

2 9 .8

65

3 .6 1

83

Feb.

3 0 .8

1 6 .8

2 3 .8

41

3 .3 4

84

M ar.

3 5 .8

20. 6

2 8 .2

60

2 .3 9

80

A pr.

4 8 .2

3 1 .3

3 9 .8

67

4 .5 3

81

M ay

7 0 .2

45. 6

5 7 .9

86

1 .9 6

74

Ju n e

7 6 .2

5 5 .8

66. 0

89

4 .7 1

78

J u ly

8 0 .5

5 6 .8

6 8 .7

90

4 .3 4

82

A ug.

7 7 .9

5 6 .1

6 7 .0

89

2 .4 5

85

S e p t.

69. 6

5 0 .7

6 0 .2

81

3 .0 2

91

O c t.

6 3 .5

4 5 .0

5 4 .3

81

1 .2 2

88

Nov.

4 0 .8

2 7 .1

3 4 .0

79

2 .9 7

83

D ec.

2 8 .8

1 6 .3

2 2 .6

49

1 .9 7

84

H l*h e s t

In ch e s

93
T A B L E XV
M E T E O R O L O G IC A L DATA F O R PA R A C H IN A R , PA K ISTA N
F O R T H E Y E A R 1950
T e m p e ra tu re

F.

A verage
M onth

R a in ­
fall
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

D a ily
M ax­
im u m

D a ily
M in ­
im u m

M onthly

Jan.

4 9 .8

2 8 .6

3 9 .2

68

2 .0 3

69

Feb.

5 1 .8

3 1 .3

4 1 .5

78

2 .6 3

68

M ar.

5 9 .8

38. 6

4 9 .2

81

4 .3 4

60

A pr.

68. 7

4 6 .9

57. 8

87

4 .0 3

58

M ay

7 9 .5

55. 6

6 7 .5

100

2 .3 1

46

Ju n e

87. 7

6 3 .7

7 5 .7

101

2 .0 0

43

J u ly

8 7 .1

6 6 .4

76. 7

102

3 .5 2

60

A ug.

84. 7

6 4 .8

7 4 .7

95

3 .7 0

67

S e p t.

8 1 .2

5 8 .6

7 0 .0

92

2 .1 1

56

O c t.

7 4 .2

4 8 .7

6 1 .5

88

0 .9 5

45

Nov.

6 4 .7

3 9 .3

5 2 .0

81

0 .4 0

48

D ec.

5 4 .8

3 2 .5

43. 6

73

1.2 3

63

H ig h e s t

94
T A B L E XV I
M E T E O R O L O G IC A L DATA F O R Q U E T T A , PA K ISTA N
F O R T H E Y E A R 1950
T e m p e ra tu re

F.

A verage
M onth

R a in ­
f a ll
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

D a ily
M ax­
im u m

D a ily
M in­
im u m

M onthly

Jan.

5 0 .2

2 7 .6

3 8 .9

78

1 .9 4

78

Feb.

5 3 .6

3 0 .8

4 2 .2

80

1 .9 8

75

M ar.

63. 6

3 8 .3

51

84

1 .7 4

67

A pr.

7 4 .0

4 5 .8

60

91

0 .9 8

63

M ay

8 3 .8

5 1 .9

6 7 .8

98

0 .3 9

54

Ju n e

9 1 .6

5 8 .7

7 5 .1

103

0 .1 7

54

J u ly

9 4 .0

6 5 .0

7 9 .5

103

0 .4 6

61

A ug.

9 2 .2

6 1 .6

7 6 .9

103

0 .3 3

56

S e p t.

8 6 .2

4 9 .7

6 7 .9

97

0 .0 4

52

O c t.

7 5 .7

3 8 .9

5 7 .3

91

0 .1 2

49

N ov.

6 5 .4

3 2 .1

4 8 .7

81

0 .2 8

55

D ec.

5 5 .5

2 8 .5

4 2 .0

76

1.01

73

H ig h e s t

95
T A B L E X V II
M E T E O R O L O G IC A L DATA F O R PESH A W A R, PA K ISTA N
F O R T H E Y E A R 1950
T e m p e ra tu re

F.

A ve r a g e
M onth

R a in ­
fall
in
In ch es

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

DailyM ax­
im u m

D a ily
Min­
im u m

M onthly

Jan.

63

4 0 .4

5 1 .7

77

1 .4 4

71

Feb.

66. 2

44

5 5 .1

86

1 .5 3

76

M ar.

7 4 .8

5 2 .4

63. 6

99

2 .4 4

69

A pr.

85. 2

6 0 .5

7 2 .8

108

1 .7 6

56

M ay

9 7 .0

7 0 .4

8 3 .7

118

0 .7 7

36

Ju n e

10 5 .0

7 7 .2

9 1 .1

120

0 .3 1

36

J u ly

1 0 2 .5

8 0 .2

9 1 .3

122

1 .2 6

58

Aug.

9 8 .2

7 8 .9

8 8 .5

118

2 .0 3

67

S e p t.

9 5 .0

7 1 .8

8 3 .4

110

0 .8 1

60

O c t.

8 7 .8

6 0 .5

7 4 .1

101

0 .2 3

52

Nov*

76. 8

4 8 .9

6 2 .8

91

0 .3 1

53

Dec.

66. 7

4 0 .9

5 3 .8

83

0. 67

65

H ig h e s t

96
T A B L E XV III
M E T E O R O L O G IC A L DATA F O R COLUM BUS, OHIO
F O R T H E Y EA R 1949
T e m p e ra tu re

F.

A verage
M onth

R a in ­
fall
in
In c h e s

% R e la tiv e
H u m id ­
ity a t
7:30
a. m .

DailyM ax­
im u m

D a ily
M in irrum

M onthly

Jan.

4 4 .1

3 0 .8

3 7 .4

63

6 .7 4

84

Feb.

4 6 .4

2 9 .5

3 8 .0

64

2 .5 3

79

M ar.

5 0 .4

33. 7

4 2 .0

76

3 .0 3

81

A pr.

5 9 .7

4 1 .6

5 0 .6

78

2 .8 4

79

M ay

7 5 .9

5 3 .4

64. 6

92

2 .0 5

79

Ju n e

8 5 .9

6 6 .1

76. 0

94

4. 47

82

J u ly

8 8 .9

6 9 .7

7 9 .3

96

3 .2 4

86

A ug.

8 4 .9

66. 0

7 5 .4

94

2 .3 7

88

S ept.

7 2 .0

5 2 .6

6 2 .3

84

2 .8 6

89

O c t.

7 0 .4

5 1 .4

6 0 .9

86

1.3 1

86

Nov.

5 1 .4

3 6 .2

4 3 .8

73

1.2 1

80

Dec.

45. 2

2 9 .0

3 7 .1

64

2 .3 7

81

H i*h e s t

97
T A B L E XIX
M E T E O R O L O G IC A L DATA F O R GRAND JU N C T IO N ,
COLORADO F O R T H E Y E A R 1947
T e m p e ra tu re

F.
R a in ­
f a ll

A verage
M onth
DailyM ax­
im u m

D a ily
M in ­
im u m

M onthly

H ighe3 t

In ch e s

% R e l­
a tiv e
H u m id ­
ity a t
5:30
a. m.

Jan.

3 4 .6

9 .5

22

48

0 .4 0

82

Feb.

47. 4

2 4 .5

36

58

0 .1 1

79

M ar.

5 6 .8

3 1 .5

4 4 .2

70

0 .6 0

67

A pr.

6 3 .9

38. 0

51

78

0 .5 9

61

M ay

7 9 .0

4 9 .6

6 4 .3

93

0 .4 1

50

Ju n e

8 0 .6

52. 6

6 6 .6

94

1 .3 8

56

J u ly

9 3 .7

6 3 .2

7 8 .4

101

0 .0 9

51

A ug.

8 7 .0

6 1 .1

7 4 .0

99

1 .2 7

65

S e p t.

8 4 .3

5 5 .6

7 0 .0

94

0 .2 6

49

O ct.

6 8 .5

4 4 .5

5 6 .5

86

1 .9 8

68

Nov.

4 4 .0

2 5 .0

3 4 .5

69

0 .6 9

78

D ec.

3 7 .9

1 9 .3

2 8 .6

49

0 .4 9

88

98
T A B L E XX
M E T E O R O L O G IC A L DATA F O R LANSING, MICHIGAN
F O R T H E Y E A R 1949
T e m p e ra tu re
A verage
M onth

R a in ­
fall
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
7:30
a. m .

D a ily
M ax­
im u m

D a ily
M in im u m

M onthly

Jan .

35. 6

2 0 .6

2 8 .1

55

3 .4 8

84

Feb.

34. 6

20. 1

27. 4

53

2 .4 7

81

M ar.

4 2 .1

2 5 .6

3 3 .8

71

2 .6 1

81

A pr.

5 7 .4

3 5 .1

4 6 .2

76

1 .8 7

78

M ay

71. 6

4 7 .4

5 9 .5

89

2 .3 5

72

Ju n e

8 2 .5

6 0 .8

71. 7

91

4 .8 9

80

Ju ly

8 4 .8

63. 4

74. 1

96

4 .7 8

83

A ug.

8 1 .8

5 8 .7

7 0 .2

93

1 .6 1

88

S e p t.

6 7 .1

4 7 .3

5 7 .2

85

1.91

83

O c t.

6 5 .5

4 4 .3

5 4 .9

84

2 .3 5

86

N ov.

4 2 .9

2 9 .0

3 6 .0

67

1 .6 0

85

D ec.

3 8 .4

2 3 .8

3 1 .1

62

4 .7 0

83

H ig h e s t

.

99
T A B L E XXI
M E T E O R O L O G IC A L DATA F O R PA RA CH IN A R, PA KISTAN
F O R T H E Y E A R 1949
T e m p e ra tu re

F.

A verage
M onth

R a in ­
fall
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

D a ily
M ax­
im u m

D a ily
M in ­
im u m

M onthly

Jan .

5 1 .9

2 8 .5

3 5 .2

64

0 .8 5

74

Feb.

4 7 .3

3 0 .8

39

63

3 .2 9

76

M ar.

5 9 .9

3 9 .8

4 9 .8

78

7 .1 9

60

A pr.

7 5 .6

5 2 .3

64

87

2 .2 4

46

M ay

8 5 .2

6 1 .3

7 3 .2

92

2 .9 9

47

Ju n e

8 3 .0

6 1 .0

72

91

0 .8 3

40

J u ly

87. 6

67. 6

77. 6

99

4 .0 6

66

A ug.

8 2 .9

63. 6

7 3 .2

88

4 .2 1

75

S ept.

8 4 .1

6 2 .8

7 3 .5

90

1 .5 1

60

O c t.

7 3 .8

4 8 .9

6 1 .4

83

0 .0 1

43

Nov.

6 2 .3

. 3 7 .5

5 0 .0

71

0 .0 8

37

Dec.

5 5 .5

32. 6

44

66

0 .6 1

71

H ig h e s t

100

T A B L E X X II
M E T E O R O L O G IC A L DATA F O R PESHAW AR, PA K ISTA N
F O R T H E Y EA R 1949
T e m p e ra tu re
A ve r a g e
M onth

R a in ­
fa ll
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

D a ily
M axim u m

D a ily
M in ­
im im

M onthly

Jan.

6 2 .9

4 0 .8

5 1 .8

73

2 .0 4

81

Feb.

6 4 .4

4 2 .7

5 3 .5

75

0 .6 9

75

M ar.

7 2 .8

52. 3

6 2 .5

87

2 .8 2

71

A pr.

8 9 .1

6 3 .0

7 6 .0

102

1 .2 4

60

M ay

1 0 0 .7

7 3 .5

8 7 .1

108

0 .5 6

43

Ju n e

9 9 .5

74. 6

8 7 .0

109

0 .4 7

39

J u ly

9 9 .7

8 0 .0

8 9 .8

110

0 .1 5

70

A ug.

9 7 .2

77. 6

8 7 .4

103

0 .3 9

56

S ept.

97. 7

7 5 .4

8 6 .5

103

0 .2 7

65

O c t.

8 5 .7

5 9 .7

7 2 .7

93 •

-

53

Nov.

7 5 .9

4 5 .5

6 0 .7

85

-

42

Dec.

6 7 .3

3 8 .5

5 2 .9

76

0 .0 7

50

H ig h e s t

.

101

T A B L E XX III
M E T E O R O L O G IC A L DATA F O R COLUM BUS, OHIO
F O R T H E Y EA R 1948
T e m p e ra tu re

F.

A verage
M onth

R a in ­
fa ll
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
7:30
a. m .

D a ily
M ax ­
im u m

D a ily
M in im u m

M onthly

Jan.

2 9 .7

1 4 .7

2 2 .2

58

2 .1 6

87

Feb.

4 1 .2

2 4 .0

32. 6

66

2. 75

85

M ar.

5 3 .7

34. 6

4 4 .2

77

3 .8 6

81

A pr.

66

4 5 .9

5 6 .0

89

4 .3 9

81

M ay

7 1 .1

5 1 .0

6 1 .0

87

3 .3 4

80

Ju n e

8 3 .1

6 1 .7

72; 4

95

3 .9 4

81

J u ly

8 6 .6

6 7 .4

7 7 .0

94

5 .2 5

85

A ug.

8 5 .4

6 3 .4

7 4 .4

100

2 .3 1

87

S e p t.

7 9 .3

5 8 .5

6 8 .9

92

2 .2 5

86

O c t.

6 1 .7

4 3 .6

52. 6

75

1 .9 8

88

Nov.

5 5 .2

4 0 .7

4 8 .0

71

3 .9 9

88

Dec.

4 3 .5

2 9 .5

3 6 .5

65

2 .2 4

85

H ig h e s t

102

T A B L E XXIV
M E T E O R O L O G IC A L DATA F O R GRAND JU N C T IO N ,
COLORADO F O R T H E Y E A R 1948
T e m p e ra tu re ° F .
A verage
M onth

R a in ­
fall
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
5:30
a. m .

D a ily
M ax­
im u m

D a ily
M in ­
im u m

Monthly

Jan.

36. 2

1 4 .7

2 5 .4

48

0 .5 0

84

Feb.

4 0 .8

19. 6

3 0 .2

54

1 .5 6

84

M ar.

4 5 .6

2 5 .3

35. 4

65

1 .5 4

76

A pr.

6 5 .9

3 9 .8

5 2 .8

84

0 .4 8

56

M ay

7 8 .1

4 9 .4

6 3 .8

92

0 .2 2

41

Ju n e

8 4 .3

5 5 .4

6 9 .8

94

0 .6 4

54

J u ly

9 3 .4

6 0 .8

7 7 .1

98

0 .8 6

50

A ug.

8 9 .2

5 9 .5

7 4 .4

97

1 .7 8

59

S ept.

8 4 .7

5 4 .4

69. 6

97

0 .6 4

51

O c t.

6 9 .2

3 9 .4

5 4 .3

83

0 .5 7

55

Nov.

4 2 .7

2 2 .3

3 2 .5

62

0 .7 0

79

D ec.

3 8 .4

1 8 .3

2 8 .4

57

0 .7 0

77

H ig h e s t

103
T A B L E XXV
M E T E O R O L O G IC A L DATA F O R LANSING, MICHIGAN
F O R T H E Y E A R 1948
T e m p e ra tu re ° F .
A verage
M onth
D a ily
M ax­
im u m

D a ily
M in - ’
im u m

H ig h e s t
M onthly

R a in ­
fall
in
In ch es

% R e l­
a tiv e
H u m id ­
ity a t
7:30
a. m.

Jan.

2 4 .2

9 .3

1 6 .8

39

1 .5 2

84

Feb.

3 1 .3

1 4 .7

2 3 .0

50

2 .0 3

84

M ar.

42. 7

23. 6

3 3 .2

64

5 .2 1

82

A pr.

6 0 .9

3 9 .8

5 0 .4

82

2 .5 2

75

M ay

6 4 .7

4 3 .7

5 4 .2

81

5 .3 5

75

Ju n e

7 5 .0

5 4 .7

6 4 .8

86

4 .4 4

79

J u ly

83. 6

6 0 .8

7 2 .2

92

1 .6 5

81

A ug.

8 3 .1

5 8 .5

7 0 .8

98

1 .8 6

85

Sept.

7 6 .7

53. 6

6 5 .2

89

1 .6 2

86

O c t.

5 8 .5

3 7 .9

4 8 .2

75

1 .0 1

87

Nov.

4 9 .1

3 6 .7

4 2 .9

66

2 .4 9

85

D ec.

35. 1

2 2 .3

28. 7

57

2 .2 3

86

104
T A B L E XXVI
M E T E O R O L O G IC A L DATA F O R PA R A C H IN A R , PA K ISTA N
F O R T H E Y E A R 1948
T e m p e ra tu re

F.

A verage
M o nth

R a in ­
fall
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

D a ily
M axim u m

D a ily
M in ­
im u m

M onthly

Jan.

5 3 .4

3 2 .1

42. 7

60

0 .5 3

66

Feb.

5 3 .0

3 2 .4

4 2 .7

61

2 .5 0

77

M ar.

5 8 .6

3 8 .6

4 8 .6

67

4. 48

70

A pr.

7 0 .1

5 0 .3

6 0 .2

84

2 .9 3

63

M ay

8 4 .8

5 6 .5

7 0 .6

92

1 .2 9

37

June

8 5 .0 .

7 5 .7

8 0 .4

93

1 .9 2

49

J u ly

8 8 .5

6 7 .2

7 7 .8

97

1 .6 5

64

A ug .

8 4 .2

6 5 .5

7 9 .8

89

3 .6 4

80

S ept.

8 3 .7

6 1 .2

7 2 .5

89

1 .1 5

61

O c t.

7 6 .9

4 5 .1

6 1 .0

84

0 .1 2

45

N ov.

6 5 .2

3 8 .9

5 2 .0

70

-

40

D e c.

5 1 .7

3 3 .0

4 2 .4

66

4. 62

71

H ig h e st

105
T A B L E XXVII
M E T E O R O L O G IC A L DATA F O R Q U E T T A , PA K ISTA N
F O R T H E Y E A R 1948
T e m p e ra tu re
A verage
M onth

R a in ­
fall
in
Inches

% R e l­
a tiv e
H u m id ­
ity a t
8:00
a. m .

D a ily
M ax­
im u m

D aily
M in ­
im u m

M onthly

Jan.

54. 1

2 5 .3

3 9 .7

61

0 .1 6

82

Feb.

5 2 .9

3 1 .6

4 2 .2

■64

2 .1 2

84

M ar. .

6 8 .8

38. 7

53'. 7

75

1 .3 2

86

A pr.

7 5 .7

4 7 .9

6 1 .8

88

0 .4 2

72

M ay

8 7 .3

5 3 .9

70. 6

92

0 .0 3

51

Ju n e

9 0 .0

5 9 .9

7 5 .0

97

0 .0 6

56

J u ly

9 5 .2

65. 7

8 0 .5

98

0. 11

62

A ug.

9 2 .0

6 1 .0

7 6 .5

98

0 .0 2

59

Sept.

8 7 .9

4 9 .7

6 8 .8

95

-

54

O c t.

7 6 .3

3 9 .9

58. 1

83

0 .3 2

60

N ov.

6 3 .5

2 6 .5

4 5 .0

73

-

50

Dec.

5 5 .0

2 9 .3

42. 1

70

H ig h e s t

1 .0 4

83

106
T A B L E X X V III
M E T E O R O L O G IC A L DATA F O R PESH A W A R, PA K ISTA N
F O R T H E Y E A R 1948
T e m p e ra tu re

F.

% R e l­

R a in ­
fall

A verage
M onth

a tiv e
H u m id ­
ity a t
8:00
a .m .

D a ily
M ax­
im u m

D a ily
Min­
im u m

M onthly

Ja n .

6 5 .9

4 0 .3

5 3 .1

71

0 .1 2

74

Feb.

65. 6

4 3 .3

5 4 .5

73

1 .1 6

82

M ar.

7 2 .7

5 0 .2

6 1 .5

84

2 .0 2

73

A pr.

8 6 .3

63. 1

7 4 .7

101

2 .1 5

64

M ay

1 0 0 .0

7 4 .8

8 7 .4

107

0 .1 9

40

Ju n e

1 0 0 .8

7 6 .9

8 8 .8

110

0 .2 6

42

J u ly

1 0 2 .2

8 0 .3

9 1 .2

114

3 .2 6

74

A ug.

9 3 .5

7 7 .4

8 5 .5

100

1 .0 9

62

S e p t.

9 4 .0

7 3 .9

8 3 .9

99

0 .0 4

53

O c t.

8 8 .4

6 3 .0

7 5 .7

94

0. 12

N ov.

7 6 .4

4 6 .8

6 1 .6

85

D ec.

6 4 .0

4 2 .9

5 3 .5

73

H ig h e s t

1 .5 6

51

56
75

■»■■»> C o l u m b u s , Ohi o.
■ —*

K* —• —

t

'■*

G rand Junction. Colorado.

107

— -* L a n s i n g . M i c h i g a n .
* P a r a c h i n a r.

** — ~ t

. . . — *—•

k

Quetta,

Pakistan.

Pakistan.

------- * p e s ha

r , Pakistan.

1 10

100

-

80 .

/

S

' .

* /

jf s ' ’

/s f r
60 -

a
40
30

20

-

j

F

A

M

]

T

s

A

O

N

D

M o t; t h

FIGURE

14

MEAN MAXIMUM T E M P E R A T U R E

F.

1050

I

C o l u m b u s , Ohio.
— —*— —-#— —
t. — • —

108

G ra n d Junction. Colorado.
Lansing.

Michigan.

Parachinar.
Ouetta.

Pakistan.

Pakistan.

Peshawar.

Pakistan.

100

80
70

w
t.

60

3

u

50

U

c.
40
30

20

10
J

F

M

A

M

J

J

A

S

O

Month

FIGURE

15

MEAN MINIMUM T E M P E R A T U R E

F.

1950

r

D

C o l u m b u s . Ohi o,

*------- y-------- *- —

109

G rand Junction. Colorado.
Lansing,

Michigan.

Pa racliina r . P a k i s t a n .
Ouetta. Pakistan.
• ««

■ • • «•

•

Peshawar,

Pakistan.

100

30
70 -

u
4s

C.
40

30

20

M

M

O

A

J

N

M o n t. h

FIGURE

16

AVERAGE MONTHLY T E M P E R A T U R E

°

F.

1950

D

109

C o l u m b u s . Ohio.
G rand Junction. Colorado.
Lansing,

Michigan.

Parachinar.
Ouetta.

Pakistan.

Pakistan.

P eshaw ar, Pakistan.

00

30

70

-

7 ,r '

40 -

20

J

F

M

A

M

' '

J

A

S

O

. N

Month

FIGURE

16

AVERAGE MONTHLY T E M P E R A T U R E ° F.

1950

D

C o lu m b u s . Ohio.
G rune! J u n c t i o n . C o l o r a to.

110

L ansing, Michigan.
P a ra c h in ar. Pakistan.
Quetta,

Pakistan.

P e s h a v n r, P a k i s t a n .

130

100

-

80

Tempo

ratur

5

60

40

M out h

FIGURE

HIGHEST T E M P E R A T U R E ° F .

17

DURING THE MONTH. 1950

*----------*

Colufn'ous. Ohio.

f ---------- j

Gr.ini

' r" '

*

11

.

Juni'ion.

Lansing.

Colorado.

IV; i ' h i g a n .

P a r a r l i i n a i*. P a k i s t a n .
■“ —* •- Q u e t t a . P a k i s t a n .
•

J

F

M

A

Peshawar.

J

Pakistan.

J

A

S

M o n t li

FIGURE
MONTHLY

18

RAINFALL.

1950

O

N

D

„ ,

,

112

C o l u m b u s . Ohio.
G ran d Junction. Colorado.
Lansing.

Michigan.

P arachinar, Pakistan,
Quetta. Pak istan .
Peshawar.

Pakistan.

100
90

80

70

X

60

c

V
u

50

u

,*
V .. «\—/ /

1/

CL

\ ’' — /

•10

30

20

10
J

F

M

A

M

J

J

A

S

Month

FIGURE

19

A1EAN R E L A T I V E H U M I D I T Y .

1950

o

N

D

113
x—

C o lu m b u s / .Qhio.

*•

G ra n d Ju n c tio n , C o lo ra d o .
-

—

V— -

L a n s in g , M ich ig an .
P a r a c h i n a r , P a k is ta n .
P e s h a w a r , P a k is ta n .

110
100
90 H
80
k

Tem perature

o

70 60 50 40 30
20
10
M

I
A

T"

J

TJ

"T—
A

“V

~T~

s

N

Month

FIG U R E 20
MEAN MAXIMUM T E M P E R A T U R E ° F .
(G ra n d Ju n c tio n - 1947)

1949

_T_

D

114
-*•
*

^

C o lu m b u s , Ohio.

— V--------T G ra n d Ju n c tio n , C o lo ra d o .

*---------- *--------<

f

L a n s in g , M ich ig an .
P a r a c h i n a r , P a k is ta n .

—■

P e s h a w a r , P a k is ta n .

100
90
80
70
- "A

60
50
40
30
20
10
A

M

J

J

A

S

O

N

Month

FIG U R E 21
M EAN MINIMUM T E M P E R A T U R E ° F .
(G ra n d J u n c tio n - 1947)

1949

D

115
C oltim bus,i O hio.
+• * —

—

t- —

T —

— ■¥■

G ra n d J u n c tio n , C o lo ra d o .
L a n s in g , M ich ig an .
P a r a c h i n a r , P a k is ta n .
P e s h a w a r , P a k is ta n .

100

80

-

50 40 30 20

-

M

M

,J

J

A

N

Month

FIG U R E 22
MEAN M ONTHLY T E M P E R A T L A E ° F .
(G ra n d Ju n c tio n - 1947)

1949

116

*--------- *--------*--------* C o lu m b u s, O hio.
-

^ it

-*•

G ra n d Ju n c tio n , C o lo ra d o .

**-------- *-------- + L a n s in g , M ich ig an .
•------- --------- --------- P a r a c h i n a r , P a k is ta n .
1

--------

•--------•

P e s h a w a r , P a k is ta n .

10
100
90
80
70
0)
u
0

+J

\

, /

60

/ /

rt

u

6)

04

50

a
ft)

H

40
30
20
10
J

F

M

A

M

J

J

A

S

O

N

D

Month

FIG U R E 23
HIGHEST T E M P E R A T U R E ° F . DURING TH E MONTH, 1949
(G ra n d Ju n c tio n - 1947)

117
C o lu m b u s , Ohio.
.

^

>f

•r ----- *— — »*

**““•------- --------- •------------

•

G ra n d Ju n c tio n , C o lo ra d o .
L a n s in g , M ich ig an .
P a r a c h i n a r , P a k is ta n .
P e s h a w a r , P a k is ta n .

9
8
7

Inche s

6
5
r

-> [

4
3
2
1
0
J

F

M

A

M

J

J

A

S

Month

FIG U R E 24
M ONTHLY R A IN F A L L , 1949
(G ra n d Ju n c tio n - 1947)

O

N

D

118

C o lu m b u s, O hio.
G ra n d J u n c tio n , C o lo ra d o
L a n s in g , M ich ig an .
P a r a c h i n a r , P a k is ta n .
P e s h a w a r , P a k is ta n .

100 n

80 70 *
■M

c

V

o

J

F

M

A

M

J

J

A

s

O

Month

FIG U R E 25
MEAN R E L A T IV E HUMIDITY, 1949
(G ra n d J u n c tio n - 1947)

N

D

*

it

tf.

*— *“ "T--------- X

—

t-

*

X

C o lu m b u s . Ohio.

119

G ran d Junction, Colorado.
Lansing. Michigan.
P a r a c h i n a r, P a k i s t a n .
Quetta, P akistan.
Peshawar.

Pakistan

110

ic e
90
r------

80

4v■
3

a
£
0.1

r-1

60

50

40

30

20
10
J

F

M

A

M

J

J

S

O

N

M o n <h

FIGURE 2 6
M E A N MA X I MU M T E M P E R A T U R E ° F.

1948

D

w- ---- X - ------*---------K

G r a n ' .’ u n c t i o n . C o l o r a

T

rt—

——

1
I

C

1

X— ------K---------*---------rf

------- I ------- 1

*—

a. ,-i^us. Oh i o .

L a •i j, i o i ’ . M i<"2: i ■>a n .
P a v a ; ina

P a a i&tan.

r .

QacUa,

. jkit.an.

P •? s \ t a w a

r

. P. >ki .■? a n .

80

v

u
3

50

o

a.
40

o
h
30

20

F

M

A

M

t

A

O

S

N

M , r.

F I G U R E 27

MEAN MINIMUM T E M P E R A T U R E

F.

1948

D

—*

C

•*———<---- —v — — “I'

i u r . ; ; u s . Oh! - / .

Jrarn.

121

J j n<•; i a n .

C . ’Jor a -'o.

L tii' iinv. JV.Jk ii
P a r af b i n d r . P ■P k; !.an.

Q-.iy*!•>.. P . » P i '»n .
P «* . s h a '•••« r .

i-’d : . < i b P

hi

.

i-' m p e r a t u r c

30

40

20

J

F

M

A

M

J

J

A

O

S

N

IVi o n Lh

F I G U R E 28
MEAN MONTHLY T E M P E R A T U R E

o

F.

1948

D

— |C-

-*

C o l u m j ’.s . Ohio.

‘X

Grand Junction.

—t—

Lansing.

Colorado.

Michigan.

P a r a china r.

122

Pakistan.

*

O n e It. a , P a k i s t a n .

*

P e s h a v. a r . P a k i s I a n .

20

110
ICO

T empe

rature

80

70

50

30

10
J

F

A

M

J

j

A

S

o

N

D

Mont h

F I G U R E 29

HIGHEST T E M P E R A T U R E

F.

DURING THE MONTH, 1948

* — ----- H--------- «— ------ *

C- ' u - ~ o v * .

* * - - < -------

G --jr.

- - *>

Ohio.

,r .110! i o n .

Cola

* — — %---------X— — X

L a n - i r . . . M i . n io’ h n .

' --------- -- --------- - - — *•-#

P<« o .i cIti no r , P a r . i s t u n

.......#
•— ----- . -------- • _ ------•

Ovic*fiu,

is, t o n .

Peshaw ar.

P;< k i s ' a t i .

Mont h

F I G U R E 30
M O N T H L Y RA I N F A L L ,

1948

i

J

~i 1

F

’-r

M

-*

C o lu m b u s, O hio.

■h

G ra n d J u n c tio n , C o lo ra d o .
L a n s in g , M ic h ig a n .

-•

P a r a c h i n a r , P a k is ta n .

-•

Q u e tta , P a k is ta n .

■*

P e s h a w a r , P a k is ta n .

i

A

1 1

M

»

J

•

J

*

A

*

»

S

O

Month

FIG U R E 31
M EAN R E L A T IV E HUM IDITY, 1948

'

N

'

D

a t G ra n d J u n c tio n ; 7 6 .2 ° to 8 0 .5 ° F . a t L a n s in g ; 8 4 .7 ° to
8 7 * 7 ° F . a t P a r a c h in a r ; 9 1 .6 ° to 94° F . a t Q u e tta ; an d 9 8 .2 °
to 105

F . a t P e s h a w a r; r e s p e c tiv e ly .

T he m e a n m a x im u m

f o r S e p te m b e r 1950 w as 7 4 .7 ° F . a t C o lu m b u s, 7 8 .3 ° F . a t
G ra n d J u n c tio n ,
8 6 .2

6 9 .6 ° F . a t L a n s in g ; 8 1 .2 ° F . a t P a r a c h i n a r ,

F . a t Q u e tta a n d 95° F . a t P e s h a w a r .

T he te m p e r a tu r e s

f o r o th e r m o n th s in th e y e a r a r e on th e w hole m u c h h ig h e r in
P a k is ta n th a n th o se in th e U n ited S ta te s of A m e ric a f o r the
s ta tio n s u n d e r d is c u s s io n .
y e a r 1950 w as 94

o

T he h ig h e s t te m p e r a tu r e d u rin g the

F . in A u g u st a t C o lu m b u s, 94

a n d S e p te m b e r a t G ra n d Ju n c tio n , 90
102° F .

in J u ly a t P a r a c h i n a r ,

o

o

F . in J u ly

F . in J u ly a t L a n s in g ;

103° F .

in Ju n e , J u ly and A u ­

g u s t a t Q u e tta a n d 122° F . in J u ly a t P e s h a w a r .

D u rin g 1948

th e h ig h e s t te m p e r a t u r e s a t P a r a c h i n a r an d Q u ette w e re below
9 8 ° F . , a lm o s t th e s a m e a s th o se a t C o lu m b u s, G ra n d Ju n c tio n
a n d L a n s in g .

O th e r f ig u r e s f o r 1948 an d th e f ig u r e s f o r 1949

show a lm o s t th e s a m e tr e n d w ith s lig h t v a ria tio n s f ro m th o se
f o r 1950.

On th e w hole th e te m p e r a t u r e s f o r P a k is ta n s ta tio n s

w e r e a fe w d e g r e e s h ig h e r th a n th o se f o r U. S. A . s ta tio n s .
T he t e m p e r a t u r e s w e re w ith in th e u p p e r v ita l lim its f o r the
v a r io u s s ta g e s of th e o r ie n ta l f r u i t m o th a t P a r a c h i n a r a n d

Q u e tta .

T he a v e r a g e s of d a ily m in im a a n d m e a n m o n th ly

t e m p e r a t u r e s w e re g e n e r a lly a few d e g r e e s above in th e c a s e
of P a r a c h i n a r a n d Q u e tta a s c o m p a re d to th o se f o r th e s ta tio n s
in U. S. A .

T h e s e t e m p e r a t u r e s w e re n e a r the o p tim u m f o r

th e o r ie n ta l f r u i t m o th e s p e c ia lly d u rin g s u m m e r and f a ll; an d
w ould n o t a ff e c t its d e v e lo p m e n t d e le te r io u s ly .

A t P esh aw ar

th e te m p e r a t u r e s o ften tim e w e re m u c h beyond th e u p p e r v ita l
l im i ts of th is in s e c t.
R a in fa ll a t C o lu m b u s, L a n s in g an d P a r a c h i n a r d u rin g
M ay to S e p te m b e r e v e ry y e a r w a s g e n e r a lly the s a m e b u t w as
m u c h m o r e th a n th a t a t G ra n d Ju n c tio n a n d Q u e tta .

T he l a s t

tw o p la c e s h a d a lm o s t a n e q u a l a m o u n t of r a in f a ll d u rin g th a t
p e rio d .
T he d a ta w ith r e g a r d to r e la tiv e h u m d ity is r a t h e r
i n te r e s ti n g .

A t C o lu m b u s a n d L a n s in g it w a s r a r e l y below

80% , u s u a lly b e tw e e n 80 a n d 90% th ro u g h o u t th e y e a r .

R e la ­

tiv e h u m id ity a t G ra n d Ju n c tio n v a r ie d f r o m 30-60% d u rin g M ay
to S e p te m b e r, w ith a m a r k e d te n d e n c y to w a rd s th e lo w e r sid e .
T h e in te n s ity of a tta c k of th e o r ie n ta l f r u i t m o th is h ig h e s t a t
C o lu m b u s a n d l e a s t a t G ra n d J u n c tio n .

A lthough th e p e s t is

p r e s e n t a t th e l a t t e r p la c e i t h a s se ld o m a tta in e d th e s ta tu s of

a m a jo r p e s t.

T h is c o r r o b o r a te s th e fin d in g s in the la b o r a to r y

b a s e d on c o n s ta n t t e m p e r a tu r e a n d h u m id ity e x p e r im e n ts , th a t
low h u m id ity , p a r t i c u l a r l y in la te s u m m e r a n d e a r ly f a ll is
h ig h ly d e tr im e n ta l f o r th e d e v e lo p m e n t of the o r ie n ta l f r u i t m o th .
T h is p ro b a b ly lim its th e g e o g ra p h ic d is tr ib u tio n of th is s p e c ie s .
In s p ite of good r a in f a ll a t P a r a c h i n a r d u rin g M ay to
S e p te m b e r th e r e la tiv e h u m id ity r e m a in e d low .

It v a rie d fr o m

40 to 70% , o fte n e r b e tw e e n 50 a n d 60% , r a r e l y going up to
7 5 -8 0 % .

P a r a c h i n a r is s itu a te d on a slo p e in the m o u n ta in s.

It a p p e a r s th a t q u ic k d ra in a g e of r a in w a te r to lo w e r le v e ls
p r e v e n ts th e r i s e of r e la tiv e h u m id ity .

T h e re w e re 5 -7 ra in y

d a y s e v e r y m o n th a n d big d o w n p o u rs on a few d a y s.
f a c t o r s a ls o w ould te n d to k e ep th e h u m id ity low .

T h ese

T he r e l a ­

tiv e h u m id ity a t Q u e tta d u rin g M ay to S e p te m b e r u s u a lly r e ­
m a in e d b e tw e e n 50 a n d 60% e v e r y y e a r .

T h u s Q u e tta is s im ­

i l a r to G ra n d J u n c tio n w ith r e g a r d to h u m id ity b u t h a s h ig h e r
te m p e ra tu re s .

A t P e s h a w a r r e la tiv e h u m id ity w as g e n e ra lly

b e tw e e n 50-60% a n d th e t e m p e r a t u r e s m o s tly h igh, o ften tim e
going b ey o n d th e u p p e r v ita l lim its f o r th e o r ie n ta l f r u i t m o th .
T h e r e i s , t h e r e f o r e , lit t le lik e lih o o d of th is p e s t g e ttin g
e s ta b lis h e d a t P e s h a w a r .

T he codling m o th w ith w hich the

128
o r i e n t a l f r u i t m o th is o ften c o m p a re d , is n o t know n to e x is t a t
P e sh a w a r.

T h e r e a r e m o re c h a n c e s f o r th e o r ie n ta l f r u i t

m o th to g e t in tro d u c e d in to Q u e tta a r e a , p a r t i c u l a r l y a t Z i a r a t
(e le v a tio n o v e r 8 ,0 0 0 f t . ) w hich r e c e iv e s m o r e r a in f a ll in
su m m er.

T he p r o b a b ility of th is in s e c t b e c o m in g a t l e a s t a

m in o r p e s t in P a r a c h i n a r a r e a is r a t h e r h ig h if by an y ch an ce
it g a in s a c c e s s to th is re g io n .

T he co d lin g m o th is a lr e a d y

doing s e r io u s d a m a g e in Q u e tta a n d P a r a c h i n a r ; w h e re it is
b e lie v e d to h av e b e en in tro d u c e d n o t long a g o .

T h e re m a y be

s e v e r a l o th e r re g io n s in P a k is ta n an d In d ia, p a r t i c u l a r l y in
K a s h m ir w h e re th e o r ie n ta l f r u i t m o th co u ld g e t e s ta b lis h e d ,
if in tro d u c e d .

T h e re a r e so m e a r e a s w h e re in a ll p ro b a b ility

i t w o u ld n o t b e c o m e a p e s t, e . g . ,

P e s h a w a r ; b u t th e r e a r e

o th e r r e g io n s w ith m e te o r o lo g ic a l c o n d itio n s s i m il a r to th o se
in th e U n ite d S ta te s of A m e ric a , w h e re th e in s e c t co u ld b eco m e
a p e s t.

It i s , th e r e f o r e , n e c e s s a r y on the p a r t of th e p la n t

q u a ra n tin e o r g a n iz a tio n s of th o se c o u n trie s to co n tin u e to ad o p t
s t r i c t q u a ra n tin e m e a s u r e s in o r d e r to c h e c k th e in tro d u c tio n
of th e o r ie n ta l f r u i t m o th .

VII.

SUMMARY AND CONCLUSIONS

T he d e v e lo p m e n t a n d fe c u n d ity of th e o r ie n ta l f r u i t m o th
w as s tu d ie d u n d e r c o n tro lle d t e m p e r a tu r e s of 6 0 °, 6 5 °, 8 5 ° a n d
95

o

F . ; a n d r e la tiv e h u m id itie s of 35, 70 a n d 100 p e r c e n t.

T he a v e r a g e in c u b a tio n p e rio d w a s 7 .0 d a y s,
d a y s a t 60

o

F . u n d e r r e la tiv e h u m id itie s of 100% , 70% and

35% , r e s p e c tiv e ly .
d a y s a t 94

o

7 .5 d a y s an d 8

T he m in im u m in c u b a tio n p e rio d w as 2 .7 5

F . , t h e r e a f t e r it i n c r e a s e d to 3 .5 d a y s a t 95

o

A la r g e n u m b e r of eg g s w ith sto o d a n e x p o s u re of 40 h o u r s
98

o

F . , b u t a n e x p o s u re of 48 h o u rs p ro v e d f a ta l.

F.
at

A n ex p o ­

s u r e of 21 h o u rs to 105° F . re d u c e d th e v ia b ility of eg g s to
25-43% an d in c r e a s e d th e in c u b a tio n p e rio d by 36-40 h o u rs .
T he in flu e n c e of r e la tiv e h u m id ity on th e d e v elo p m e n t
of e g g s

though s ig n ific a n t w as n o t w e ll- m a r k e d .

h a tc h e d

a co u p le

of h o u rs e a r l i e r

th o s e u n d e r low a n d h ig h h u m id ity

T he eggs

u n d e r 70% h u m id ity
o
e x c e p t a t 5 0 .5

th an
o
a n d 60 F .

A t 5 0 .5 ° F . th e in c u b a tio n p e rio d w as 24 d a y s u n d e r 100%
r e la tiv e h u m id ity a n d 25 d a y s u n d e r 70% r e la tiv e h u m id ity .
A t 94° a n d 95° F . th e e g g s d id n o t h a tc h u n d e r 35% r e l a ti v e
h u m id ity .

T h e in flu e n c e of r e l a t i v e h u m id ity s e e m e d to be

m o r e m a r k e d on th e v ia b ility of th e e g g s th a n on th e in c u b a ­
tio n p e rio d .
It is e v id e n t f r o m th e d a ta th a t th e e g g s of th e o r ie n ta l
f r u i t m o th c a n to le r a te f a i r l y h ig h te m p e r a t u r e s a n d low h u m id ­
itie s .

P e r h a p s th e f la tte n e d an d s c a le lik e f o r m of the e g g s

h e lp s th e m in r e s i s t in g th e e ffe c t of a d v e r s e c o n d itio n s.
The a v e r a g e fe e d in g p e rio d of th e la r v a e v a r ie d f r o m
3 6 .8 1 d a y s a t 65° F . to 1 8 .0 d a y s a t 95° F .

T h e re w e re

la r g e in d iv id u a l v a r ia tio n s w ith in one lo t of la r v a e k e p t u n d e r
u n if o r m c o n d itio n s.
T he d u ra tio n of th e p u p al s ta g e d e c r e a s e d w ith the r i s e
o f t e m p e r a tu r e f r o m 19 d a y s a t 65

o

F . to 11 d ay s a t 95

T he r a t e of d e v e lo p m e n t d e c e le r a te d beyond 75

o

F.

o

F.

The te m ­

p e r a t u r e a t w h ich th e la r v a e w e re g ro w n h a d a d is tin c t in flu ­
e n c e on the d u ra tio n of the p u p a l p e rio d a t a n o th e r te m p e ra tu re ..
P u p a e k e p t a t 65° F . f o r m e d f r o m la r v a e gro w n a t 85° F . had
a lo n g e r p u p a l d u ra tio n a s c o m p a re d to th o se a t o th e r c o m b in a ­
tio n s of t e m p e r a t u r e s .

T he p u p a l p e rio d w as found to be

s h o r t e s t u n d e r 100% a n d lo n g e s t u n d e r 35% re la tiv e h u m id ity .
A low r e l a t i v e h u m id ity w a s h ig h ly d e t r i m e n t a l to pu pae k e p t
a t 85

O

F . w h en t h e i r egg a n d l a r v a l p e r i o d s h a d b e e n a t 65

O

131
o r 75

F.

U s u a lly th e v ia b ility of pupae w a s a b o u t one a n d a

h a lf tim e s th e fig u re f o r 70% r e la tiv e h u m id ity .
a t 65
a t 85

F o r p u p a e,

F . a n d 35% r e la tiv e h u m id ity , f o rm e d f ro m la r v a e g ro w n
o

F . i t w as l e s s th an o n e - th ir d a s c o m p a re d to th o se k ep t

u n d e r a s a tu r a te d c o n d itio n . ‘ T he v ia b ility of pupae w as a lw a y s
h ig h e s t u n d e r s a tu r a te d a tm o s p h e r e a t a ll th e c o m b in a tio n s of
t e m p e r a t u r e t r ie d .

T h is m e a n s th a t in a r e a s of low h u m id ity

in la te s u m m e r an d e a r l y f a ll a l e s s n u m b e r of m o th s e m e rg e .
C o n se q u e n tly , th e d a m a g e to f r u i t s in th o se a r e a s is lik e ly to
be n e g lig ib le .

On th e o th e r h a n d p la c e s w hich a r e m o re h u m id

m a y h a v e l a r g e r e m e rg e n c e of m o th s , an d p ro p o rtio n a te ly
g r e a t e r d a m a g e to f r u i t s f r o m th e la te b ro o d s of la r v a e .
T he th e o r e tic a l th r e s h o ld of d e v e lo p m e n t f o r eggs is
fo u n d to be 4 0 ° -4 4 ° F . d ep en d in g upon th e r e la tiv e h u m id ity ;
lo w e s t u n d e r 100%; a n d , h ig h e s t u n d e r 35% r e la tiv e h u m id ity .
F o r l a r v a e it is 4 3 .5 ° F . ; w h e r e a s f o r pupae it v a r i e s fro m
4 6 .5 ° F . to 5 2 .5 ° F . u n d e r r e la tiv e h u m id itie s of 100% and
35% , r e s p e c tiv e ly .

U n d e r m o is t c o n d itio n s th e eg g s a n d the

p u p ae (two s ta g e s a ffe c te d by h u m id ity ) co n tin u e d e v elo p m e n t
a t lo w e r t e m p e r a t u r e s ,
d itio n s .

c o m p a re d to th o se e x p o se d to d ry con­

In a r e a s w ith m o is t c lim a te , p a r t i c u l a r l y th o se h av in g

r e la tiv e h u m id itie s v a ry in g f r o m 80 to 90% the in s e c t c a n ^ s t a r t
d e v e lo p m e n t e a r l y in s p rin g a n d th u s in c r e a s e to la r g e p r o p o r ­
tio n s a n d c a u s e s e r io u s d a m a g e .

T he d if fe re n c e s b e tw ee n

th r e s h o ld s of d e v e lo p m e n t f o r v a rio u s s ta g e s a t h ig h a n d low
h u m id itie s a r e m o r e f o r th e o r ie n ta l f r u i t m o th th a n in th e c a s e '•
o f th e co d lin g m o th ; show ing th a t th e f o r m e r p r e f e r s m o re m o is t
c o n d itio n s f o r its d e v e lo p m e n t.
T he la r v a e of the o r ie n ta l f r u i t m o th w e re found to e n te r
in to a s h o r t d ia p a u se f o r a p e rio d of 31 to 60 d a y s, and, a
lo n g d ia p a u s e w ith a d u ra tio n of o v e r 60 d a y s u n d e r v a rio u s
te m p e r a t u r e s a n d h u m id itie s .

T he l a r g e s t n u m b e r a n d lo n g e s t

p e r io d of " s h o r t d ia p a u s e " w as in th e c a s e of la r v a e r e a r e d
a t the o p tim u m te m p e r a tu r e of 75
7 5 ° o r 8 5° F .

o

F . a n d k e p t a s co co o n s a t

C o m p a ra tiv e ly m o re la r v a e e n te r e d s h o r t d ia ­

p a u s e u n d e r d r i e r c o n d itio n s.
T he m a x im u m d u ra tio n of "long d ia p a u s e " in clu d in g the
p u p a l p e rio d w a s 241 d a y s a t 65° F . (la r v a e g ro w n a t 65° F . ) ,
184 d a y s a t 65° F .
F.

(la rv a e r e a r e d a t 85° F . ) ,

(la rv a e r e a r e d a t 75

r e a r e d a t 75° F . ) .
a t 65° F . ,

F.),

126 d a y s a t 75

162 d a y s a t 65
F.

(la rv a e

E x c e p t f o r th o s e la r v a e k e p t p e rm a n e n tly

th e h ig h e r th e te m p e r a tu r e f r o m w hich th e y w e re

133
t r a n s f e r r e d to 65 , th e lo n g e r th e d ia p a u s e .

T h is is in a g r e e ­

m e n t w ith th e o b s e r v a tio n s in th e o r c h a r d s .

L a r v a e h ib e r n a t­

ing e a r l y in f a l l o r s u m m e r w hen the t e m p e r a t u r e s a r e h ig h
h a v e a lo n g e r d ia p a u se th a n th o se h ib e rn a tin g l a t e r in th e s e a ­
so n .

T he h ib e rn a tio n w as m o s t s u c c e s s f u l u n d e r 100% r e l a ­

tiv e h u m id ity .

T h e s e in v e s tig a tio n s h av e show n th a t p h o to -

p e r io d is m d id n o t h av e a n y a p p re c ia b le e ffe c t on the in d u ctio n
of d ia p a u s e , a s 64.3% an d 50% la r v a e s u c c e s s f u lly c o m p le te d
d ia p a u s e a n d e m e rg e d a s m o th s , e v en though th e y w e re gro w n
in to ta l d a r k n e s s a t 6 5° F . a n d 75° F . , r e s p e c tiv e ly .

The

r e a l c a u s e w h ic h in itia te s d ia p a u se in th e la r v a e of th e o r ie n ta l
f r u i t m o th a p p e a r s to be in h e r e n t an d is to so m e e x te n t in flu ­
e n c e d by th e n a tu r e an d q u a lity of food on w hich th e y a r e fed .
T h e p e rc e n ta g e of m o th s e m e rg in g u n d e r d iff e re n t co n ­
d itio n s is g iv e n .

U n d e r 35% r e la tiv e h u m id ity p r a c tic a lly one

h u n d re d p e r c e n t of th e m o th s e m e r g e d f r o m th e s h o r t cy cle
l a r v a e , a t m o s t of th e t e m p e r a t u r e s .
w a s a t a c o n s ta n t te m p e r a tu r e of 75

In f a c t the only ex ce p tio n
F.

G e n e ra lly about h a lf

o f th e to ta l m o th s e m e rg e d f r o m long c y cle la r v a e if th e r e l a ­
tiv e h u m id ity h a d b e e n 100% d u rin g th e coco o n p e rio d ; ab o u t
o n e - th ir d if i t h a d b e e n 70% ; a n d n il w ith 35% r e la tiv e h u m id ity ,

e x c e p t 7 .7 % a t 75° F .

T h is in d ic a te s th a t th e la r v a e of the

o r i e n t a l f r u i t m o th , in a r e a s w h e re low r e la tiv e h u m id ity p r e ­
v a ils d u rin g la te s u m m e r a n d e a r ly f a ll la r g e ly e m e rg e a s
m o th s an d n o t go in to h ib e rn a tio n .

If the c o n d itio n s a r e d ry

v e r y fe w la r v a e e n te r in to d ia p a u se o r c o m p le te it s u c c e s s ­
fu lly .

A s m a ll e r n u m b e r of m o th s e m e rg e in the fo llo w in g

s p r in g on th e r e t u r n of fa v o u ra b le c o n d itio n s.

On th e o th e r

h a n d , a s u b s ta n tia lly l a r g e r n u m b e r of la rv a e m a y e n te r d ia ­
p a u s e a n d c o m p le te it s u c c e s s fu lly , if the r e la tiv e h u m id ity to
w h ich th e y a r e e x p o se d d u rin g the cocoon p e rio d is h igh enough.
T he l a t t e r a d a p ta tio n e n s u r e s g r e a t e r s u rv iv a l of th is s p e c ie s
in r e g io n s w h e re h ig h h u m id ity p r e v a ils in la te s u m m e r and
f a ll.

T h u s th e p r e s e n t g e o g ra p h ic d is trib u tio n of the o r ie n ta l

f r u i t m o th a p p e a r s to be la r g e ly g o v e rn e d by th e re la tiv e h u ­
m id ity p r e v a ilin g f r o m J u ly to N o v e m b e r, th e p e rio d w hen l a r ­
v a e e n te r d ia p a u s e .

In h u m id a r e a s G . m o le s ta is f a r m o re

a b u n d a n t th a n in the d r i e r re g io n s .

T h is d iffe re n c e is e x p la in e d

h e r e by th e in flu e n ce of r e la tiv e h u m id ity on i ts d e v e lo p m e n t
a n d on th e s u c c e s s f u l c o m p le tio n of la r v a l d ia p a u se .
T h e o p tim u m ra n g e of t e m p e r a t u r e f o r egg lay in g w as
75° to 85° F .

The m o th s la id eggs w hen k e p t in d a r k n e s s b ut

135
th e to ta l n u m b e r of e g g s la id w as l e s s .

T he f e m a le s e m e rg in g

f r o m th e h ib e rn a tin g m a t e r i a l la id v e r y few e g g s a s c o m p a re d
to th o se f r o m th e s h o r t c y c le la r v a e .

T he fe c u n d ity of m o th s

e m e rg in g f r o m m a t e r i a l a t low h u m id itie s w a s lo w e r th a n th a t
of th o s e w ith p r e im a g in a l life u n d e r h ig h h u m id itie s .

M oths

e m e rg in g f r o m m a t e r i a l g ro w n a t a n o r d in a r y ro o m te m p e r a tu r e
o f 7 0 -8 0

o

F . , la id 74. 5 eg g s p e r fe m a le d u rin g th e p e rio d

S e p te m b e r 24th to O c to b e r 15, 1950.
b e r,

1950, to A p r il,

In the m o n th s of N o v e m ­

1951, th e a v e r a g e p e r fe m a le v a r ie d f r o m

3 .3 to 9 .6 e g g s in th e la b o r a to r y .

D u rin g M ay,

1951, the

a v e r a g e i n c r e a s e d to 57. 1 e g g s an d to 65. 4 e g g s d u rin g Ju n e ,
1951.

T h e re w as w ide flu c tu a tio n in the a v e ra g e n u m b e r of

e g g s la id p e r fe m a le f o r d iffe re n t p e r io d s d u rin g th e y e a r in
th e la b o r a to r y , w h e re te m p e r a tu r e c o n d itio n s w e re a lm o s t the
s a m e th ro u g h o u t th e y e a r .

It a p p e a r s th a t m o th s of s u c c e s ­

siv e g e n e r a tio n s e v e n th o u g h fe d on th e s a m e food la y v a ry in g
n u m b e rs of e g g s.
M e te o ro lo g ic a l d a ta f o r th e y e a r s 1948 to 1950 f o r th r e e
ty p ic a l s ta tio n s in th e U n ite d S ta te s of A m e ric a h av e b een
c o m p a r e d w ith th o se of th r e e p la c e s in P a k is ta n .

T h e re is

l it t le lik e lih o o d of th e o r ie n ta l f r u i t m o th g e ttin g e s ta b lis h e d

136
in p la c e s w h e re low h u m id ity p r e v a ils d u rin g s u m m e r a n d f a ll
a s th e p e s t d e v e lo p s b e s t u n d e r h ig h h u m id itie s of 8 0 -9 0 % .
T he p r o b a b ility of th is in s e c t b e c o m in g a t l e a s t a m in o r p e s t
in p la c e s lik e P a r a c h i n a r , (P a k is ta n ) w h e re th e m a x im u m te m ­
p e r a t u r e s e ld o m g o e s above 98° F . a n d the r e la tiv e h u m id ity
is o fte n a ro u n d 5 0 -6 0 % , is r a t h e r h ig h .

It is , th e r e f o r e , n e c ­

e s s a r y on th e p a r t of th e p la n t q u a ra n tin e o rg a n iz a tio n s of
P a k is ta n a n d India to c o n tin u e to a d o p t s t r i c t m e a s u r e s in o r ­
d e r to c h e c k th e in tro d u c tio n of the o r ie n ta l f r u i t m o th into
th o se c o u n tr ie s .

VIII.

A hm ad,
1941

L IT E R A T U R E C IT ED

r.

an d G h u la m -U lla h
E c o lo g ic a l S tu d ie s on th e S p o tted B o llw o rm s of
C o tto n a n d T h e ir P a r a s i t e s .
II.
T he F e c u n d ity
a n d L o n g e v ity of E a r i a s fa b ia a n d Its P a r a s i t e ,
M ic ro b ra c o n le f r o y i u n d e r D iffe re n t C o n d itio n s
of T e m p e r a tu r e an d H u m id ity .
Indian J o u r .
E n t . Ill, 2 :2 4 5 -2 8 4 .

A ld e n , C . H. a n d C la rk e , W. H.
T he L ife H is to r y and C o n tro l of th e O rie n ta l
1931
F r u i t M oth.
G e o rg ia S ta te B o a rd of E n to m o lo g y
B u l l., 7 4 :1 -2 3 .
A lle e , W . C, , E m e r s o n , A . E . , P a r k , O . , P a r k , T .
a n d S c h m id t, K. P .
P r i n c ip l e s of A n im a l E c o lo g y : 837 pp.
W. B.
1949
S a u n d e rs C om pany, P h ila d e lp h ia an d L ondon.
C u trig h t,
1937

C. R.
C odling M oth B io lo g y an d C o n tro l In v e s tig a tio n s.
O hio A g r ic . E x p t. S ta . B u l l., 5 8 3 :1 -4 5 .

D ic k so n , R . C.
F a c t o r s G o v e rn in g th e Ind u ctio n of D ia p a u se in
1949
th e O r ie n ta l F r u i t M oth. A n n . E n t. S o c . A m e r ­
i c a , X L II, 4 :5 1 1 -5 3 7 .
D u s ta n ,
1932

3. G.
O b s e rv a tio n s on th e R e la tio n of T e m p e r a tu r e
a n d M o is tu re to th e O r ie n ta l P e a c h M oth. E n t.
S o c . O n ta rio , A n n . R e p o r t, 6 3 :2 9 -3 9 .

E d d y , C. O . , a n d N e ttle s , W. C.
B io lo g ic a l S tu d ie s of O r ie n ta l F r u i t M oth, 1930.
1931
S. C a ro lin a A g r ic . E x p t. S ta. B u l l., 2 7 8 :1 -2 1 .

138
8.

9..

10.

F r o g a t t, W. W.
1914
P e a c h T ip M oth.
1914, p . 413.

N ew South W ales A g ric . G az.

G a rm a n , P .
1917
T he O r ie n ta l P e a c h P e s t ( L a s p e y r e s ia m o le s ta
B u sc k ), a D a n g e ro u s N ew F r u i t In s e c t of M a ry ­
la n d .
M a ry la n d A g r ic . E x p t. S ta. B u l l ., 209:
1 -1 6 .
G a rm a n , P .
1930 T he O r ie n ta l P e a c h M oth in C o n n e c tic u t.
A g r ic . E x p t. S ta . B u l l., 3 1 3 :4 0 1 -4 5 1 .

Conn.

11.

G len n , P . A .
1922 C odling M oth In v e s tig a tio n s of th e S ta te E n to ­
m o l o g i s t s O ffic e .
ELI. N a t. H is t. S u rv . B u ll.,
14 :2 1 9 -2 8 9 .

12.

H a ru k a w a , C.
1923 S eco n d N o te s on the O rie n ta l P e a c h M oth, L a s ­
p e y r e s ia m o le s ta B u sc k . B e r . O h a ra In st.
L a n d w irt. F o r s c h . in K u ra s c h ik i, Ja p a n , II, 3:
2 3 5 -2 3 8 .

13.

H a ru k a w a , C.
1929 R e la tio n of T e m p e r a tu r e to th e G ro w th of the
O r ie n ta l P e a c h M oth.
I. B e r . O h a ra In st.
L a n d w irt. F o r s c h . in K u ra s c h ik i, Ja p a n , IV,
1 :6 7 -9 4 .

14.

H a e u s s le r , G. J .
1940 G e n e r a l In fo rm a tio n C o n c e rn in g th e O rie n ta l
F r u i t M oth in J a p a n an d C h o sen .
J o u r . E co .
E n t . , 3 3 :1 8 9 -1 9 3 .

15.

H e in ric h , C a r l
1926 R e v is io n of th e N o rth A m e ric a n M oths of the
S u b fa m ilie s , L a s p e y r e s iin a e , an d O le th re u tin a e .
U. S. N a tio n a l M u seu m B u l l ., 132:28.

i

139
16.

H o d g m an , C . D.
1949
H andbook of C h e m is try a n d P h y s ic s , p i 951.
C h e m ic a l R u b b e r P u b lis h in g C o ., C le v e la n d ,
O hio.

17.

I s e ly , D.
1939' T im in g S e a s o n a l O c c u r re n c e a n d A bundance of
th e C odling M oth. A r k a n s a s A g r ic . E x p t. St.
B u l l ., 3 8 2 :1 -2 6 .

18.

K ro g h , A u g u st
1914
On th e In flu en ce of T e m p e r a tu r e on th e R ate of
E m b ry o n ic D e v elo p m en t.
Z ts c h r . A llg . P h y s io . ,
2 9 :2 9 -3 6 .

19.

N e w c o m e r, E . J . a n d W hitcom b, W. D.
1924
L ife H is to r y of th e C odling M oth in Y ak im a V a l­
le y of W ash in g to n .
U. S. D. A . B u l l., 1235.

20.

P e t e r s o n , A . , a n d H a e u s s le r , G. J .
1930
L ife H is to r y of th e O rie n ta l P e a c h M oth a t
R iv e rto n , N . J . , in R e la tio n to T e m p e r a tu r e .
U. S. D. A . T e c h . B u l l., 18 3 :1 -3 8 .

21.

Q u in ta n c e , A . L . an d W ood, W. B .
1916
L a s p e y r e s i a m o le s t a , a n Im p o rta n t N ew In s e c t
E n e m y of th e P e a c h .
J o u r . A g r i c . R e s . , VII,
8 :3 7 3 -3 7 8 .

22.

S a n d e rs o n , E . D . , a n d P e a i r s , L . M.
1914
T he R e la tio n of T e m p e r a tu r e to In s e c t
L ife .
T e c h . B u ll. N. H . C o ll. A g ri. E x p e r. St. 7.

23.

S h e lfo rd , V. E .
1927
A n E x p e r im e n ta l In v e s tig a tio n of th e R e la tio n s
of the C od ling M oth to W e a th e r an d C lim a te .
111. N a t. H is t. S u rv . B u l l., 16:307-446.

24.

S napp, O. I. a n d S w ingle, H. S.
1929
L ife H is to r y of th e O rie n ta l P e a c h M oth in
G e o rg ia .
U. S. D. A . T e c h . B u l l., 1 5 2 :1 -1 6 .

1

140
25.

S q u ire , F . A .
1940
O b s e rv a tio n s o th e L a r v a l D ia p a u se of th e P in k
B o llw o rm , P la ty e d r a g o s s y p ie lla Saund.
B u ll.
E n t. R e s . , 3 0 :4 7 5 -4 8 1 .

26.

S te a r n s , L . A .
1921
T he L ife H is to r y of the O rie n ta l F r u i t M oth in
N o r th e r n V irg in ia .
V irg in ia A g r i. E x p t. S ta.
P o ly . In st. T e c h . B u l l., 2 1 :1 -4 6 .

27.

S te a r n s , L . A . , a n d P e t e r s o n , A .
1928
T he S e a so n a l L ife H is to r y of th e O rie n ta l F r u i t
M oth in N ew J e r s e y d u rin g 1924, 1925 a n d 1926.
N ew J e r s e y A g ric . E x p t. S ta . B u ll., 4 5 5 :1 -4 8 .

28.

S te a r n s , L . A . , a n d N e is w a n d e r, R . B.
1930
O r ie n ta l F r u i t M oth In v e s tig a tio n s in Ohio I.
O hio A g r ic . E x p t. S ta . B u l l., 4 5 7 :1 -3 6 .

29.

U v a ro v , B . P .
1931
In s e c ts a n d C lim a te .
L o n d o n , 79:1 -2 4 7 .

30.

T r a n s . R o y . E n t. S o c.

W ood, W. B . , a n d S e lk re g g , E . R.
1918
F u r t h e r N o te s on L a s p e y r e s ia m o le s t a .
A g r i c . R e s . X III, 1 :5 9 -7 2 .

Jo u r.