.. .1: = .9, r, _

 

s"
E

I
O

213 chrm at

In. 4‘-
3: .

a.
r.
O

t

“(38 £5

=1
1:

W ‘- "if;

we
{II

:2.

q
22“?

Q
I

.

I

\

#2::
M

' 3.
{It -'

.' 4'".
3"»:

f.
a 1%

K

 

0-169

9 '1'. ‘n ' " . ._..- 4A A V I
_. A). __ .. - 4.— ..--. . _.. 3---.

This is to certify that the

thesis entitled

The Effect of Various Nutrient
Intensities on Granth and Development
of Snapdragon (Antirngfinum majus L)

presented 139

Harrison L. Flint

has been accepted towards fulfillment
of the requirements for

Ldegtee lil'u-g

 

 

 

 

 

 

'63-"- -I o

i-
I

THE EFFECT OF VARIOUS NUTRIENT INTENSITIES ON THE
GROWTH AND DEVELOPMENT OF SNAPDRAGON
(ANTIRRHINUM MAJUS L.)

BY

Harrison L. Flint

v

A THESIS

Submitted to the School of Graduate Studies of Michigan
State College of Agriculture and Applied Science
in partial fulfillment of the requirements

for the degree of

MASTER OF SCIENCE

Department of Horticulture

Year 1952

ACKNOWLEDGEMENTS

I wish to eXpress sincere appreciation to Dr. Sam
Asen for supervising the conduction and presentation of
this research, and for guidance and inepiration throughout.

I am also grateful to Drs. Walter J. Haney and
Garrick E. Wildon for answering many questions about the
snapdragon and for helping me in interpreting some of
the data.

Grateful acknowledgement is also due to Mr. C. Maynard
Emslie of Barre, Vermont, for his large contribution to
my understanding of commercial production of snapdragons,
and for discussing this work with me from a commercial
viewpoint.

I am also indebted to Dr. Erwin J. Benne for helping
me carry out the chemical analyses, to Dr. Edward N.
Learner for the photography, and to my fellow students for
encouragement and assistance in interpreting some of the

data.

$11 $4}{‘;;?

Part

II

III

IV

TABLE OF CONTENTS

INTRODUCTION . . . . . .
MATERIALS AND METHODS. .
A. Plant Material. . . .
B. Nutriculture Methods.

1. Apparatus. . . . .

2. Nutrient solutions

C. Analytical Methods. .

O
O
O

O O O O

1. Physical measurements. . . .

2. Chemical analyses.
RESULTS AND DISCUSSION .

A. Observations. . . . .
1. Leaf color . . . .
2. Flower color . . .
3. Flower carriage. .
u. Number of leaves .

5. Length of time unti

O
O
O
O
1

O O 0 0
I 0 O 0
O O O O
O O O O
O O O O
maturit

B. Physical Measurements . . . . .
1.Dryweight.........

2. Stem length. . . .

Y

.0.

0.0...

3. Number of flowers per inflorescence.
h. Stem strength and hardness . . . . .

Ce Chemical Analyses e e e e e e e

D. General Discussion of Results .

SUMMARY. 0 . . . . . . .
BIBLIOGRAPHY . . . . . .

.0...

0.0...

0....

Page

OxO~O NF: w w

I. INTRODUCTION

A normal sequence of crOp rotation in commercial
floricultural greenhouses frequently has been the growing
of snapdragons following a crOp of chrysanthemums. This
practice, without first removing some of the soluble
fertilizer from the soil, often has resulted in serious
injury. The belief has grown that the salt tolerance of
the snapdragon is low in comparison to other crepe.
Fertilizer recommendations have been made largely on
growers' observations, owing to the small amount of
detailed investigation which has been devoted to this
problem.

The work of Post and Bell (f1) in 1936 indicated that
snapdragons can be severely injured when subjected to
excesses of single salts. Injury was observed as chlorosis
of the young leaves, accompanied by a retardation of
growth.

Laurie and Kiplinger'L5) have stated that, except
for initial additions of superphosphate, no nutrients
need be added to a moderately fertile soil for satisfactory
growth of snapdragons. Elaborating on this, they have
mentioned that the snapdragon is strikingly non-responsive

to nitrogen fertilizer during the fall and winter, but will

respond to light applications in the Spring.

Howland, in 19h6 (4), working with the snapdragon,
found flower production and quality to be affected very
little by relatively large variations in nitrogen and
potassium fertilization. '

Post (5) has observed that excessive amounts of
fertilizer in the soil caused chlorosis of the foliage.
He suggested that in the soil extract nitrates be main-
tained at ten to fifty parts per million, phosphorus at.
five parts per million, and potassium at thirty parts per
million, in terms of the Spurway acetic acid extraction.

The purpose of this investigation was to determine
the effects of nutrient intensity on the growth and
deveIOpment of the snapdragon, as well as some of the

relationships between nutrient intensity and nutrient

absorption.

II. MATERIALS AND METHODS
A. Plant Material

Snapdragon plants used in this study were grown from
seed. The following two varieties were selected for this
work:

1. Margaret: an ivory-colored inbred variety, pepular

for commercial production.

2. M.S.C. #13: a rose-colored hybrid, recently
deveIOped at Michigan State College,
which exhibits a high degree of heterosis.

April 5, 1952, seeds were sown in a mixture of equal
parts by volume of soil, sand, and acid peat. May 6,
seedlings were selected for uniform height and leaf
development and transplanted into No. 8 grade quartz sand.*
The plants were watered with a dilute nutrient solution
until roots were established and evidence of new growth
had appeared. The composition of this solution was:
0.00025 M KH2POu, 0.00085 M Ca(N03)2, 0.00065 M MgSOu,

0.00065 M K230“, 0.0006 M (NHLQZSO and 0.00025 M CaClZ.

h!
Microelements were added at the following concentrations:
2.50 ppm Fe, 0.50 ppm.Mn, 0.50 ppm B, 0.05 ppm Zn, 0.02 ppm

Cu, and 0.01 ppm.M0. Treatments were started on May 17, 1952.

 

*Purchased from the American Graded Sand Company of
Chicago, Illinois.

(I

"

 

B. Nutriculture Methods
1. Apparatus.

The sand culture technique as described by Robbins
(8.), with some modification, was used. Plants were grown
in two-gallon glazed earthenware crooks in quartz sand.
This method was particularly suited to this type of study,
since the inert medium could be washed free of nutrients
and then provided with known concentrations. Each crock
was connected to a five-gallon carboy containing the
nutrient solution. The solutions were forced into the
crooks by compressed air, as shown in Figure l. The desired
time of Operation was set by the clock (A) which released
the solenoid valve (B). This allowed compressed air to
pass through the air line (C), which was open into the
water column (G). In this way, pressure was exerted on
the nutrient solution (D)'in each carboy (E), forcing it
into the crock (F). The clock was set to close the
solenoid valve after five minutes of Operation. When the
valve was closed, the air pressure was dissipated into
the water column (G) and the solutions drained back into
the carboys by force of gravity. The height to which the
solutions could rise in the crooks was governed by the
height of the water column (G). I

The crooks were spaced in two rows on a bench and
the assigned treatments were randomized and replicated

four times.

A general view of the apparatus is shown in Figure 2.

.ggagglflfioilg 48.3..

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

.
. .
. :
x ,.
..\
i

a e .
.. . .
.. . v .. 1.. ..

... . x. . . -

_ ox . q

’ (8.3. I... .
3.; u.
. I .. 5!: radiant...”

mcflflw areal ( J
t 3 ,

  

 

(h... .

 

{wrilv‘mifud.
A . Q .
. lieu.
. . Tin:
.2... . . .
”fix .
x.
. e #8.. ..

e
f.

..‘ I. .
iv»..-
. x .
. .(zru. ., . ..

In... . .

f)

 

01,
.L

2. Nutrient solutions

A base nutrient solution was formulated from infor-
mation obtained in preliminary studies. The solution was
designated as the X salt concentration. The other treatment
solutions used were one-fourth, one-half, two times, and
four times the X concentration. Treatments were designated
as .25X, .50X, X, 2X, and Rx. Concentrations of micro-
elements were the same in all treatments. Details of the
composition of the treatment solutions are given in Table 1.

These solutions were prepared from 0.5 molar stock
solutions and were made to a volume of ten liters in each
carboy. This volume was maintained throughout the experi-
ment, distilled water being added through the crooks.

This also prevented the accumulation of salts at the surface
of the sand. Salts used were either Baker's Analyzed or
Merck Reagent grade. Distilled water was used throughout.

'When the solutions were prepared, pH measurements
were obtained with a Beckman pH meter. These measurements
also were made at two to eight day intervals while the
solutions were in use. Since the values varied from pH
u.6 to pH 5.8 in a three-week period, no adjustments were
made. The solutions were renewed every three weeks.

Osmotic pressure was calculated for each solution,
using ionization values tabulated in the Handbook 3;
Chemistry gnQ,Ph sics. The values calculated are given in
Table l.

Ho.o
No.0
mo.o
om.o
om.o
om.N

Ednepnhaoz
hemaoo

OGHN

omezdwcez
donom

noAH

AcoHHHHE neg muaeav.maueaoacopoHE no coupeApcooaoo

 

 

 

0e.m 0100.0 0000.0 00H0.0 :0H0.0 omH0.0 0300.0 a:

0:.H 0m00.0 0:00.0 mm00.0 mm00.0 0e00.0 0m00.0 am

m~.0 0H00.0 :m00.0 0m00.0 0m00.0 :m00.0 0H00.0 a

wm.0 m000.0 mH00.0 ma00.0 mH00.0 ~H00.0 m000.0 a m.

0H.0 mm000.0 0000.0 m0000.0 me000.0 m0000.0 mm000.0 xmm.
A.spav oasmm.n0 «no.0 sommxsmzv iEmma some: mimozvao 00mmma psoepa.ea

capoemo pepdfldoaeo

 

evade Aches no noapenpceoaoo neaoz

 

 

 

it.“

'lly

1"

All!

mZOHBqum azmza<mma mme mo ZOHBHmomEOU

H qu<e

C. Analytical Methods

1. Physical measurements

Measurements to determine the effects of treatment

on growth and development were as follows:

1.
2.

3.

h.

5.

Dry weights of various plant parts.

Stem length: measured from the location of the
cotyledons to the distal end of the inflorescence.
Number of flowers per inflorescence: total number
capable of opening. The number of flowers capable
of Opening was determined from the appearance of
the flower buds when approximately one-half of the
inflorescence had opened.

Stem diameter: measurement made at a point equi-
distant from the location of the cotyledons and
the base of the inflorescence.

Hardness of stem tissue. One-inch segments of
green stem were taken from that place on the stem
where the diameter measurement was made. This was
done when two-thirds of the potential flowers had
opened. Evaluation of hardness was expressed as
shearing force in pounds per square inch as measured

by a Tenderometer.*

In addition to these measurements, observations were

made of leaf color, flower color, flower carriage, number

of leaves, and time of maturity.

 

*This apparatus was designed by the American Can Company

for use

in the canning industry.

10

2. Chemical analyses

Chemical analyses were made for nitrogen, phosphorus,
potassium, calcium, and magnesium. The total leaf tissue
was collected when two-thirds of the flowers had opened
and was prepared for analysis as suggested by Ulrich (9).

Nitrogen was determined as total ammonium and amino
forms by the Kjeldahl method (1). PhOSphorus was deter-
mined by precipitation of ammonium phospho-molybdate and
titration with standard potassium iodate. Potassium was
determined with a Perkins-Elmer flame photometer. Calcium
was determined by precipitation of the oxalate and titration
with standard potassium.permanganate. Magnesium.was
determined gravimetrically by precipitation of the dihydrous

phosphate and ignition to the pyrophosphate.v

III. RESULTS AND DISCUSSION

A. Observations

1. Leaf color

Observations of leaf color were made using color

standards developed at Cornell University for apple trees
(2). The color of the leaves of plants grown at the
.25X, .50X, and X treatments was similar. The 2X treat-
ment resulted in intervenal chlorosis on newly-formed '
leaves (see Figure 3). Similar but more extensive and
severe chlorosis was observed on plants grown at the ax
treatment. It is difficult to attribute the chlorosis to
any given cause, other than to consider it to be an

indirect result of the high concentration of salts.

2. Flower color
No obvious differences in flower color were observed
with the ivory-colored variety, Margaret. The rose-colored
variety, M.S.C. #13, however, exhibited considerable fading
at the 2X treatment. This was more pronounced at the 4x

treatment.~

3. Carriage of flowers
The carriage of the flowers in the inflorescence was
compared by observing the angle between the axis of a fully

Open flower and the stem (see Figure h). An angle of

 

t

j 5&2:

.{el 'l‘

 

CS

IA.

 

- t,“ D m m‘

 

 

$7

A

\\ ’_
x
\.

x a . ..
\\ bridw .. new —.
\ .2. x - r}...

\

h“-~mmr‘~

 

1h

approximately sixty degrees was considered normal for

these varieties. The flowers of plants grown at the

.25X, .50X, and.X treatments were normal. In the 2X treat-
ment, the angle was smaller than normal. This became

more pronounced at the hx treatment, generally thirty to

thirty-five degrees, as shown in Figure h and Figure 5.

h. Number of leaves
Counts were made of the number of leaves formed on
a plant prior to the develOpment of flower buds. All
plants formed 25 (i.2) leaves, no variation occurring
between treatments. Apparently mineral nutrient intensity
has little or no effect on the morphological age at which

flowering occurs.

5. Length of time until maturity
Plants were harvested when two-thirds of the flowers
in the raceme had Opened. No differences were noted
between the four treatments of lowest nutrient intensity.
A decrease (five to six days) in time required for matur-
ation was noted at the Ex treatment. This may have been

due to retarded growth and accumulation of carbohydrates.

B. Physical Measurements
1. Dry weight
The dry weights of individual parts of plants grown
under the various treatments are shown in Table 2. It is

apparent from these data that the two varieties exhibited

 

16

.00.a -Hopoa H0. “0~.H -Hopoa 00. “sponges x 000E00000
"unmask woman deuce na eonencuufia pneoaufinmfie pueeoq *

 

 

 

0.0 0.0 0.0 0.0 0.0 0.0 0.0 as
0.0 0.0 0.0 e.a 0.0 . 0.0 H.a am
0.0 0.0 0.0 0.0 0.0 0.0 0.a a
0.0 0.0 0.0 0.0 H.~ 5.0 0.0 an.
m.» 0.0 0.0 0.0 0.0 a.0 0.H amm.
00H00000.MH%,.0.0.E
0.0 0.0 0.0 0.0 0.0 0.0 0.0 M0
0.0 0.0 0.0 0.H N.H 0.0 N.H M0
0.0 0.0 H.0 0.0 0.a 0.0 0.H a
0.0 e.0 0.0 0.0 0.H 0.0 0.H N0.
0.0 0.0 0.0 0.H ~.H 0.0 0.H amm.
Acenpnflu pensmncz
seesaw epoom do» nasacpeq Scum daemon encroam pncaeeene
dance Haven.

 

 

Aaaunw we cemmcnawmv

mzoe<mnmazm mam .0.m.a 024 90000042
5 20300000.” 05.0.42 ha 20 030.00% 0.205002 E0 980%

N MflmdB

17

differences in vigor and response to treatment. The
inbred variety, Margaret, produced a significantly smaller
amount of dry matter than the hybrid, M.S.C. #13, except
at the .25X and .50X treatments.

The dry weights reflect serious injury to both vari-
eties at the 2X treatment. This injury was further accent-
uated at the more intense 4X treatment. Plants grown at
the hX treatment produced approximately one-third as much
dry matter as those grown at the X treatment.

The inbred variety showed a significant increase in
the .50X treatment over both the .25X and.X treatments,
indicating that a point of maximum dry matter production
probably occurred somewhere near the .50X intensity.

The hybrid variety, however, exhibited no difference in
dry matter between the .50X and X treatments, indicating
that this hybrid, under conditions that prevailed, could
utilize a more intense concentration of nutrients than the
inbred variety.

It is interesting to note that, of the total tOp
growth produced, the percentage contributed by lateral
shoots increased to a maximum at the X treatment. Increasing
the salt concentration from .25X to X resulted in an in-
crease in the percentage of dry weight contributed by
lateral growth from 31 to 39 percent for the inbred variety
and from 32 to AS percent for the hybrid. This is in
agreement with Laurie and Kiplinger (5) who state that the

 

 

l8

addition of nutrients, especially nitrogen, to a reason-
ably fertile soil will Often result in "grassy" growth, or
an abundance of lateral shoots. The relationship between
lateral growth and nutrient intensity may suggest a growth
regulator-nutrient interaction, resulting in the suppression

of apical dominance.

2. Stem length

The influence of nutrient intensity on stem length
is shown in Table 3. The hybrid produced a longer stem
than the inbred at the .25X, .50X, and X treatments.
Little varietal difference was expressed at the 2X and RX
treatments. It is evident that the hybrid was more severely
injured than the inbred variety by the high salt concen-
trations, with reSpect to stem length as well as dry
matter production.

Greatest stem length for the inbred variety occurred
at the .25X and .50X treatments. For the hybrid variety
this extended also to plants grown at the X treatment.
This demonstrates that an "Optimum” nutrient intensity
for longitudinal growth would be slightly higher for the
hybrid than for the inbred variety.

3. Number of flowers per inflorescence
As shown in Table h, the number of flowers per inflor-
escence did not vary appreciably between the .25X, .50X,
and X treatments, in either variety. However, at the 2X

concentration the number of flowers was reduced in the

19

TABLE 3

EFFECT OF NUTRIENT INTENSITY 0N STEM.LENGTH OF
MARGARET AND M.S.C. #13 SNAPDRAGONS
(expressed as centimeters)

 

 

 

==iiggip __i_____________
Margaret NLS.C. #13
Treatment (inbred) (hybrid)
.25x _73.6 80.6
.sx 73.2 ' 81-9
x 69.0 79.0
2x 60.0 59.0
4X 43.4 45.0

 

Lowest significant difference:
Treatment X variety: .05 level- 5.19; .01 level- 7.27

20

TABLE h
EFFECT OF NUTRIENT INTENSITY ON NUMBER OF
FLOWERS PER INFLORESCENCE IN MARGARET
AND M.S.C. #13 SNAPDRAGONS

(Averages of twelve plants per treatment)

 

 

 

Treatment ¥§£§§§2§ Mz§§géifi%3
.25X 25 2h
.5 X 26 2h
X 26 23
2X 20 16

 

21

inbred variety by 23 percent, and in the hybrid by thirty
percent. At the hX concentration, the inbred variety
showed a 58 percent decrease from the X concentration,

and the hybrid showed a decrease of 61 percent.

h. Stem strength and hardness
Shearing force, as shown by the tenderometer readings
in Table 5, was a measure of stem strength. Since these
values do not take into account the differences in stem
thickness, a factor of stem hardness was calculated.
This factor was termed the Hardness Coefficient and
was derived in the following manner:

H = Hardness Coefficient

T
H = , where:
d T

: Tenderometer reading
(pounds per square inch)
d.= diameter of stem (centimeters)

The diameter (d) is squared in the calculation in
order that the correction.might be for thickness of stem
(prOportional to the area of a cross section) rather than
for stem diameter. Obviously, the Hardness Coefficient is
only of value as a means of comparing; as an absolute value
it is meaningless. Both the shearing force measurements
and the stem diameter measurements were made on tissue
from a point halfway between the location of the cotyledons
and the base of the inflorescence.

It is shown in Table 5 that, with the varieties used,
the .25X treatment produced stems with the highest Hardness
Coefficient. With the inbred variety, a gradual decrease

22

Asov
NaepeaeHO Beam
030:0 caeswm hem medzomq MGHOeoa nopcsoneocea n p000000heoo unenpaen fl_m =0:

nepeSoaeoneB s 00 veanmeos as 50:0 endows pea apnoea 00 echo“ wn00eenm **
.eeen cacoen use nOHpcoo0 :oeoahpoc 800% unspe0c0sve 90000 as upsesoasmees.00< *

 

 

 

 

00.0 00.0 0.00 00.0 00.0 0.00 00
00.0 00.0 0.00 00.0 00.0 0.00 00‘
00.0 00.0 0.00 00.0 00.0 0.00 a
00.0 00.0 0.00 00.0 00.0 0.00 a m.
00.0 00.0 0.00 00.0 00.0 0.00 000.
080v “Soy
m hepchHp aamnapsea m nepeEeHO aawc0osea
eat .Eepm hepofioaepdee **# Beam Aeneaoaepaea
10000000 000 .0.0.: 10000000 000000.: 000s0..na

 

 

#Apacapeea» nose :0 09:000 ebaezp pom mesasb emsae><v

mzow<mmmdzm MH% .o.m.z

92¢ emmdwmdz mo mzmaw mo mmMZQm<m 92d maczmmam mmB zo MBHmszZH EzmHmEDz mo Bommmm

m mgm<a

23

in hardness was observed as nutrient intensity increased.
The greatest hardness for the hybrid also occurred at the
.25X treatment, but little difference was observed between

other treatments.
C. Chemical Analyses

The influence of nutrient intensity on the mineral
composition of the snapdragon leaves is shown in Table 6.
In general, the hybrid variety exhibited a lower percentage
composition of nutrient elements than the inbred variety.
This may well have been a function of dilution, owing to
the greater production of dry matter by the hybrid.

Mineral nutrient content was found to be quite high
in the snapdragon leaves. This is in agreement with the
results of Gartner (3).

The nitrogen content of the leaves increased progress-
ively with increased concentration of this and other
elements in the nutrient solution. The contents of
phosphorus and potassium showed strikingly similar trends.
An increase of 1600 percent in the concentrations of
nitrogen, phosphorus, and potassium in the nutrient
solution (from the .25X to the Ex treatment) caused a
fifty percent increase in the concentrations of these
elements in the leaf tissue. While the treatment series
was a geometric progression of concentrations in the

nutrient solution, the content of these elements in the

2L.

 

 

 

000.0 00.0 00.0 000.0 00.0 000.0 00.0 00.0 000.0 00.0 00

000.0 00.0 00.0 000.0 00.0 000.0 00.0 00.0 000.0 00.0 00

000.0 00.0 00.0 000.0 00.0 000.0 00.0 00.0 000.0 00.0 x

000.0 00.0 00.0 000.0 00.0 000.0 00.0 00.0 000.0 00.0 x 0.

000.0 00.0 00.0 000.0 00.0 000.0 00.0 00.0 000.0 00.0 000.

I0: .0 a .0 z 0: .0 . a 0 z 00.50.00.
00000000 000 .0.0.: 00000000 000000.:

 

 

 

000000» meea 00 930003 000 oopo ho pooopem ms penneadxmv

MBHmzmezH EZMHmBDz Mm QMUZQDQRZH md mm><md zowdmmmdzm mo ZOHBHmomSOO Q<mHZHZ

o mumde

25

leaf tissue more nearly approached an arithmetic progression.

The calcium content of the leaves was not greatly
affected by the intensity of the nutrient solution. Pre-
sumably the balance of macroelements in the nutrient
solution was more instrumental in regulating calcium
absorption than were the absolute amounts of calcium.in
the nutrient solution. If any effect is discernible, it
would seem that the calcium content decreases slightly
with increased nutrient intensity.

There seemed to be no correlation between nutrient
intensity and magnesium content of the leaves, although

considerable differences appeared between certain treatments.
D. General Discussion of Results

These results indicate that the snapdragon can be
injured severely under an environment corresponding to
the 2X or hX treatment (Figures 6 and 7). The best growth,
in terms of dry matter production, occurred with plants
grown at the .50X treatment with the inbred variety, and
at a slightly higher nutrient intensity with the hybrid.

For commercial snapdragon production, the .25X
concentration could be designated as the "Optimum” treat-
ment, since the .50X and X treatments only increased
lateral growth, but did not increase the commercial quality
of the flowers. It is not necessary, nor even desirable
in commercial production to obtain strong lateral growth,

unless second-crepping is to be practiced.

..4;

87

 
    

\¢}( .- if”
< "at. “@1551

’3 .3“ n:.'w'[=‘:' ".54.?

‘. Vt
- . (0

I ‘1'.”

4‘; I ‘13.;

'(Ix.
‘ ‘\ J.

'.'\‘~‘ld(¢" \ d“;

.‘f' w)! tqa 526‘ l').
' >

‘ ‘I’L (”RV-ll? ’A"~ I. 0‘s! n .
- -"." PA“;I’U\ ”9H" (1‘

I .

(fi' . h, - ‘ 6'0; ‘. ’ ‘
J.‘ t" I?“ ”(435:0 E‘,‘ _ '

O .r'.

3 2" ‘:.‘ \Vy W‘rg “in;

.’, .
.
\l
4

1.0.,

-- "l

't ’06; it.
J‘A‘L/ w» .3“ i535.) A‘U’

rip." ::V,.u'?!~v
V,

'e‘.“
\.‘..i“‘ 1"!

‘6 ' "3 S", 0“
0f

 

IV. SUMMARY

A. Snapdragon plants were grown in quartz sand and
supplied with nutrient solutions of five different inten-
sities. One of these five treatments was based on pre-
liminary studies and designated as X concentration. The
others were one-fourth, one-half, two times, and four times
the K concentration.

B. Two varieties, Margaret (ivory-colored inbred) and
M.S.C. #13 (rose-colored hybrid), were used.

C. Plants were seriously injured by the high salt
concentration treatments, 2X and AX. Symptoms of salt
injury were:

1. Intervenal chlorosis on young leaves.

2. Fading of the flower color in the rose-
colored variety, not noticeable in the
ivory-colored variety.

3. A general retardation of growth.

u. Decrease in number of flowers per inflorescence.

All symptoms were more pronounced at the fix treatment
than at the 2X treatment.

b D. The .50X treatment was found to be near-Optimum
for growth, in terms of dry matter production. However,
the .25X treatment, which produced less lateral growth and

blooms of good commercial quality, might well be considered

29

to be nearer the Optimum for commercial production.

E. Chemical analyses showed a direct relationship
between nutrient intensity and the nitrogen, phosphorus,
and potassium contents of the plant leaves. The calcium
content was little affected by the treatments. The
magnesium content differed between treatments, but not
in a systematic manner.

F. The hybrid variety differed from the inbred variety
in that:

1. It suffered more severe injury at the 2X
and MX treatments.

2. It reSponded to slightly higher intensity
of nutrients.

3. It showed a slightly lower content of nutrient
elements in the leaves, probably due to
dilution as a result of greater dry matter
production.

G. As a result of this investigation, it is
recommended that commercial snapdragon growers avoid a
high nutrient intensity. Apparently, the needs of the
crOp are much lower than those of many other crOps commonly

grown under glass.

I 11" 1.11 ‘l

1.

2.

3.

h.

S.

6.

7.

BIBLIOGRAPHY

Literature Cited

 

Association of Official Agricultural Chemists.
Official and Tentative Methods g£_Analysis, 6th Ed.,
I9QS.

Compton, O. 0., w. G. Granville, D. Boynton and E. S.
Phillips. Color standards for McIntosh ap 1e leaves.
Cornell Univ. Agr. EXp. Sta. Bul. 82h, 19h .

 

 

Gartner, John Bernard.
Interrelation of response to indoleacetic acid,
duration and intensity of light, and heterosis in
the snapdragon (Antirrhinum ma us L.). Doctoral
Thesis, Michigan State College, 952.

 

Howland, Joseph E.
Foliar dieback of the greenhouse snapdragon Antirr—
hinum majus and a study of the influence of certain
environmen al factors upon flower production and
quality. Proc. Am. Soc. Hort. Sci. h7:u85-h97, l9h6.

Laurie, Alex and D. C. Kiplinger.
Commercial Flower Forcing. The Blakiston Company,
0

Philadelphia, T§K8

Post, Kenneth.
Florist CroE Production and Marketing. Orange Judd
Publishing Company, Inc.. New York,_l950.

 

 

Post, K. and Robert 8. Bell.
Effect of excess fertilizers on roses, snapdragons,
and chrysanthemums. Proc. Am. Soc. Hort. Sci. 3h:

6uu, 1936.

Robbins, W. R.
Growing plants in sand culture for experimental
work. Soil Sci. 62(1):3-22, 19h6.

Ulrich, Albert.
Chap. VI. Plant analysis - methods and interpretation
of results. Kitchen, Herminie 8., Editor. Diagnostic
Techniques for Soils and Croos. The American Potash “
Institute,‘washington:_5.0.9 pp. 157-198, l9u8.

 

(‘

1.

2.

3.

31

Literature Not Cited

Bray, Roger H.
Chap. II. Correlation of soil tests with crop
response to added fertilizers and with fertilizer
requirement. Kitchen, Herminie B., Editor.
Diagnostic Techniques for Soils and Crons. The
American PotashfiInstitute, Washington, D.C.. pp.

53'86, 19480

Kiplinger, D. C. and Alex Laurie.
Growing ornamental greenhouse crOps in gravel
culture. Ohio Agr. EXP. Sta. Res. Bul. 679, 1948.

 

Lucas, R. E., G. D. Scarseth and D. H. Sieling.
Soil fertility level as it influences plant
nutrient composition and consumption. Purdue Univ.
Agr. EXP. Sta. Bul. #68, 19h2.

Magistad, O. C. 22 3;.
Effect of salt concentration, kind of salt, and
climate on plant growth in sand cultures.
P10 Phy81010 183151-166, 19u3.

l

-.W. ho.
. it)“ ‘I..N~”\ \'u
($1.9«W J...(.< ..\...¢...

1:... ..-.. .L... ..v.
.NwW.....:. 2...... . t

5.:9’.
IU.J4.

 

 

 

-. __ - a...
v D 4 I
.‘ \| \ l1
.Inum v, - u . . - w...
l u. I -
. \.
. , .. - x I -
4..
ES - . .
- [U 4
- .. , - 1....
\. , .x. -.
Ill.
. . ..-.
as"... .... - .
i an. . .
. DU . . w - , _
u w is“ . .. t. \ . hm
. u .0 .\
. \ . . s to ..
fl » 1
. . 0 -2- r
. Ru - :9
. M x - -
— I 9 I 0
_ J ‘

 

\ v
I . .h \
I L 4 n
'3. 1 (a to ‘ d l l
V ‘ 'Q I r
I.
I! .4 I I \ /
\ - I .6! - til 0
\ K u L n.
.F' . r
v \ ' W I \ Q
| l u' \ i. ' (I
9 9 b' ’ '4‘ 5 \\ I
‘ <‘ I I II
' . .‘ ' l ’.
. l . Q .
'4 v t s I
I‘l‘ _ I.
.v
v I n I v I
I I ‘ ‘ '9
|\ b D ’
- lo: 1' \ x . I '
.l 1 :1 0| I v V Vin. \
I s n a .4
4 . It“.
I a J
' “ t A
u . .1. \ .I .
4’
O I
f I ah i!
I
t.
I
I I I
I a
I r
n e | u
l l
I

 

1293 02098 5283