,THE COURSE OF STONE CELL FORMATION JN THE FEAR FRUITS .By W illiam W* Sm ith A, THESIS P re s e n te d t o th e G-raduate School of M ichigan S ta te C ollege o f A g r ic u ltu r e ,and A pp lied S cience in P a r t i a l F u lf illm e n t o f R equirem ents .fo r t h e Degree o f D octor o f P h ilo so p h y H o r tic u ltu r e D epartm ent E a st L an sin g , M ichigan 1935 ' /< /? - ProQuest Number: 10008430 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest, ProQuest 10008430 Published by ProQuest LLC (2016). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 481 0 6 -1 3 4 6 INTRODUCTION C r i s t and B a t j e r ’ s (7) a n a ly s e s of th e i s o l a t e d g r i t c e l l c l u s t e r s o f p e a r f r u i t s show th e s e s tr u c t u r e s to be a p p ro x im a te ly t h r e e f o u r th s li g n o c e l l u l o s e , o f which about a t h i r d is l i g n i n . This q u a n t ita ­ t i v e r e l a t io n s h i p o f th e c o n s titu e n ts was c o n s is te n t in th e s e v e ra l sam ples t e s t e d , and made p o s s ib le q u a n t i t a t i v e e s tim a te s o f th e g r i t c e l l c o n te n t o f th e f r u i t s by lig n o c e llu lo s e d e te rm in a tio n s . T h e ir h i s t o l o g i c a l s tu d ie s re v e a le d c e l l w a ll th ic k e n in g s 20 days a f t e r b lo s s o m - f a ll, and ch em ical a n a ly s e s in d ic a te d l i g n i f i c a t i o n o c c u rrin g two or th re e days a f t e r blossom ­ ing# The accu m u latio n o f lig n o c e llu lo s e a s a p e rc e n ta g e o f th e d ry w eig h t pro ceed ed r a p id ly fo r about fo u r weeks, rea c h in g a c o n c e n tr a tio n of h a l f th e f r u i t ’ s d ry w e ig h t, th e n began s h a rp ly to d e c re a se u n t i l a t h a r v e s t tim e i t amounted to ab o u t a f i f t h o f th e d ry w eight# D uring th e p e rio d o f l i g n i f i c a t i o n th e r e o c c u rre d a ste a d y d e c lin e i n th e r e l a t i v e amounts o f a lc o h o l e x t r a c t a b l e m a t e r ia l, which reached a minimum a t th e same tim e th e (■i ■ lig n o c e llu lo s e reach ed a maximum# At t h i s p o in t, in d ic a te d by a d ecrease in th e p e rc e n ta g e o f l i g n i f i e d t i s s u e , began th e accu m u latio n o f a lc o h o l e x t r a c t a b l e m a te r ia l which co n tin u ed f o r th e r e s t o f th e grow ing season# How p e r f e c t l y th e r e l a t i v e amount o f a lc o h o l e x tr a c ta b le sub­ s ta n c e s can be a r e c ip r o c a l o f th e amounts of li g n o c e ll u lo s e , in two v a r ­ i e t i e s o f p e a rs s tu d ie d , can be seen in F ig u re 21 of C r i s t and B a t j e r ’ s r e p o r t (7)# For exam ple, th e K ie f fe r f r u i t s on May 18 had an a lc o h o l ex­ t r a c t a b l e c o n te n t o f 55 p e rc e n t o f th e d ry w eight, which dropped to n e a r ly 25 p e rc e n t th e l a t t e r p a r t o f June, and th e n in c re a s e d s t e a d i l y , re a c h in g a c o n c e n tr a tio n of 55 p e rc e n t a g a in by Septem ber 2# 98855 a lc o h o l e x t r a c t is composed l a r g e l y o f su g ars# The lig n o c e llu lo s e s t a r t e d o f f w ith a concen­ t r a t i o n o f ab o u t 25 p e r c e n t, reached a maximum th e l a s t o f June o f o v e r 55 p e r c e n t and th e n dropped o f f to 25 p e rc e n t by September# T his same i n t e r - r e l a t i o n o f th e s e m a te r ia ls was found in th e B a r t l e t t v a r i e t y o f p e a r s , which in c o n tr a s t to th e K ie f f e r , is le s s " g r i t t y * and shows a low er p e rc e n ta g e o f l i g n o c e ll u l o s e , co u p led w ith a h ig h e r p e r ­ ce n tag e o f a lc o h o l e x t r a c t a b l e su b stan ces# I t i s a ls o i n t e r e s t i n g t h a t th e "c o n v e rsio n p o in t" , so to sp eak , i n t h i s v a r i e t y i s about a week e a r l i e r , - a t which tim e th e r e l a t i v e amounts o f th e s e m a te r ia ls co rresp o n d c lo s e ly w ith th o se o f th e K ie f f e r . The re g ­ u l a r i t y o f t h i s t y p i c a l change in r e l a t i v e c o n c e n tra tio n s f o r a l l v a r i e t i e s o f p e a r f r u i t s s tu d ie d , grown u n d er d i f f e r e n t c u l t u r a l c o n d itio n s , in w idely s e p a ra te d l o c a l i t i e s , f o r s e v e ra l u n lik e se a so n s, e s ta b li s h e s i t as a funda­ m en tal b a s ic phenomenon and as th e in h e re n t o rd e r o f th e s e changes in grow­ in g p e a r f r u i t s # In g e n e r a l, th e ch em ical changes in c id e n t to c e l l w all fo rm a tio n a r e i n th e d i r e c t i o n o f l i g n i f i c a t i o n . So f a r as th e a u th o r is aw are, th e l i t e r a t u r e p r e s e n ts no c l e a r - c u t ev id en ce o f a r e v e rs io n in t h i s order# The s u g g e s tio n o f C r i s t and B a t j e r , however, t h a t su ch a r e v e rs io n o ccu rs in ­ c id e n t to th e developm ent o f g r i t c e l l s in th e p e a r , lig n o c e llu lo s e b e in g tra n sfo rm e d to s u g a rs , makes d e s ir a b le a f u r t h e r stu d y o f th e chem ical changes o c c u rrin g i n th e s e s t r u c t u r e s . The r e s u l t s o f s tu d ie s o f s e v e ra l in v e s tig a to r s su g g est a t h e o r e t i c a l c o u rse o f e v e n ts in th e p ro c e ss o f l i g n i f i c a t i o n of p la n t t i s s u e w hich may be in d ic a te d by th e fo llo w in g diagram s Qo^ctenea^tfo/^ _ / P^oduc t s sr 'Peqiin&.-'CO^ Hefa/cellalose Lf'a/zoce//u - < % 'S **V XmLJmSLmlJmmL /?c i d s I t i s known t h a t th e f i r s t p ro d u c ts o f p h o to s y n th e s is , t r a n s ­ lo c a te d as m onosaccharides o r d is a c c h a r id e s , a re s u g a rs (9) (21) (29) and t h a t th e end p ro d u c ts , in th e l i g n i f i c a t i o n of p la n t t i s s u e s , a re li g n o c e llu lo s e s (11) (16) ( 1 7 ). The co u rse th e su g a rs fo llo w and th e changes th e y undergo to reach t h i s f i n a l s ta g e i s a p o in t o f fundam ental c o n c e rn , A g r e a t d e a l o f in v e s t ig a ti o n has "been done, c h ie f ly on woody m a t e r i a l , to g e t a c lu e to t h i s co u rse o f e v en ts (3) (5) (8) (10) (11) ( 2 1 ). T hat th e su g a rs condense to foim p o ly s a c c h a rid e s , th e r e i s no d o u b t, (25) (2 7 ). That th e y o x id iz e to form su g a r a c id s known as p o ly u ro n ic a c id s , i s su p p o rte d hy th e r e s u l t s o f c e r t a i n r e s e a r c h (25) ( 2 7 ). The p o ly u ro n ic a c i d s , - g a lo c tu r o n ic , g lu c u ro n ic , and o t h e r s , a re o f p a r t i c u l a r i n t e r e s t b ecau se th e y combine w ith c e r t a i n co n d e n sa tio n p ro d u c ts ( a r a b in o s e , g a la c to s e ) (12) (13) (15) to f o m p e c tin s , and a l s o , th e y seem t o be a p a r t o f th e h e m ic e llu lo s e s (5) (2 4 ). Change o f p e c t i n t o h e m ic e llu lo s e was f a i r l y w e ll e s ta b lis h e d by C an d lin and S ch ry v er ( 5 ) . In t h e i r in v e s tig a tio n s on chem ical changes ta k in g p la c e i n c e l l w a ll su b sta n c e s d u rin g l i g n i f i c a t i o n , th e y group th e s u b sta n c e s accompanying c e l l u l o s e in c e l l w a lls in to th r e e c l a s s e s ; p e c tin s , - 4 h e m ic e llu lo s e s and l i g n i n s . They were ab le t o d e c a rb o x y la te p e c tin s w ith th e fo rm a tio n o f h e m ic e llu lo s e s which resem bled i n a l l r e s p e c ts th e h e m ic e llu lo s e s i s o l a t e d d i r e c t l y from tim b e rs . T h e ir r e s u l t s in ­ d i c a t e t h a t d e c a rb o x y la tio n ta k e s p la c e when p la n t t i s s u e s l i g n i f y . They were u n a b le , how ever, t o e s t a b l i s h a d i r e c t c o n n e c tio n betw een p e c tin s and lig n in s . The aim o f t h i s i n v e s t i g a t i o n was to seek a d d it io n a l ev id en ce o f movement to r i g h t a s in d ic a te d by th e fo re g o in g diagram, { i . e . - from su g ars th ro u g h p e c t i n s , e t c . to l i g n o c e l l u l o s e ) , to examine th e p o s s i b i l i t y o f a r e v e r s a l o f th e d i r e c t i o n o f movement, and a ls o to f a r t h e r th e o b je c tiv e o f r e l i e v i n g p e a r f r u i t s g e n e r a lly , th o se of th e K ie f f e r in p a r t i c u l a r , from th e bu rd en o f g r i t t i n e s s on i t s q u a l i t y . TECHNICAL METHODS Sam pling - The m a te r ia l u sed f o r lig n o c e llu lo s e d e te rm in a tio n s was sam pled a s d e s c rib e d by C r is t and B a tje r ( 7 ) ; t h a t i s , tr a n s v e r s e segments were c u t from th e c e n te r o f each f r u i t , th e l o c u l i o f th e c a r p e ls removed, and th e segm ents d r ie d ih an e l e c t r i c oven a t 65° C. For c a rb o h y d ra te and p e c t i n a n a ly s e s s im i l a r p o r tio n s of th 4 f r u i t s , as were used f o r l i g n o c e l l u ­ lo s e , were ta k e n . m ixed. These were f i n e ly ground i n a meat g r in d e r and th o ro u g h ly Small amounts were p la c e d in w eigh b o t t l e s f o r d ry w eight d e te rm in a ­ t i o n s , made a t 95° C. Samples c o n s is tin g o f 25 grams o f t h i s m a te r ia l were q u ic k ly weighed and dropped in to mason j a r s c o n ta in in g b o il i n g 95 p e rc e n t a lc o h o l o f s u f f i c i e n t volume to g iv e a f i n a l c o n c e n tr a tio n , in c lu d in g th e m o istu re o f th e sam ple, o f 80 p e rc e n t a lc o h o l. B o ilin g was c o n tin u e d f o r 10 m in u tes a f t e r which th e j a r s were s e a le d and s to r e d f o r a h a ly s e s . Seduc­ t i o n s o b ta in e d in s im i l a r sam ples b o ile d 10, 30 and 60 m inutes in d ic a te th a t com plete e x t r a c t i o n o f th e re d u c in g su b sta n c e s was o b ta in e d by b o il in g 10 m inutes* Sm all amounts o f calciu m c a rb o n a te were added t o th e f i r s t sam ples t to n e u t r a l i z e th e a c i d s , b u t b ecau se o f th e sm all amounts o f a c id s p re s e n t and th e s h o r t p e rio d o f h e a tin g , i t seemed t h a t h y d r o ly s is would be n e g l i ­ g ib le . A rchbald (2) in a r e p o r t on work w ith a p p le s s t a t e s ; "No d if f e r e n c e was found i n th e e s tim a te d amounts o f s u g a r in u n tr e a te d s o lu tio n s compared w ith s o lu tio n s t r e a t e d w ith ca lciu m c a rb o n a te d u rin g th e h o t e x t r a c tio n or w ith ammonia d u rin g b o th c o ld and h o t e x t r a c t i o n s . H y d ro ly sis d u rin g a l ­ co h o l e x t r a c t i o n i s t h e r e f o r e presumed to be n e g l i g i b l e . ” The f i r s t s e a s o n ’s stu d y showed t h a t th e ca lc iu m c a rb o n a te i n t e r f e r e d w ith th e p e c ti n d e t e r ­ m in a tio n s by n e u t r a l i z i n g th e weak a c id u sed i n e x t r a c t i n g t o t a l p e c t i n s . T h e re fo re , i t was o m itte d i n f u tu r e sam ples. A n a ly sis - Benzene e x t r a c t i o n s , a lc o h o l e x t r a c t i o n s , w a te r e x tr a c ­ t i o n s , and a l k a l i e x t r a c t i o n s were made and th e c e llu lo s e and l i g n i n d e t e r ­ m in a tio n s se c u re d a s d e s c rib e d by C r is t and B a tje r ( 7 ) . T o ta l s u g a rs , s u c ro s e , d e x tr in s , s t a r c h and h e m ic e llu lo s e s were d eterm in ed a s o u tlin e d by th e com m ittee on chem ical m ethods of th e American S o c ie ty o f P la n t P h y s io lo g is ts (3 1 ). P e c tin s as calciu m p e c ta te were d eterm in ed by th e method e s ta b ­ lis h e d by C arre and Haynes (6) and employed by Appleman and Conrad ( l ) . D uring th e grow ing seaso n o f 1930 and 1931, re d u c in g su b sta n c e s were d eterm in ed by th e m o d ified S haffer-H artm ann t i t r a t i o n method (30) ( 3 3 ). The su g a r s o lu tio n s o b ta in e d by ta k in g up th e a lc o h o l e x t r a c t s i n w a te r, b e in g q u ite f r e e o f c o lo r in g m a tte r , were used d i r e c t l y to av o id lo s s of su g a rs w hich m ight be thrown down in th e c le a r in g p ro c e ss ( 4 ) . I n v e s tig a tio n s by P h i l l i p s (28) in d ic a te t h a t w ith c e r t a i n m a te r ia ls th e S h affer-H artm an n method g iv e s h ig h v a lu e s . He c i t e s S u lliv a n (34) as f in d ­ in g t h a t io d in e l i b e r a t e d i n th e p resen ce of p la n t e x t r a c t s may be absorbed by some c o n s titu e n t o f th e e x t r a c t , su ch as p h lo r h iz in , c au sin g an e r r o r i n th e d e te r m in a tio n o f th e red u ced co p p er. To t e s t t h i s p o s s i b i l i t y , re d u c tio n s were .d ete rm in ed on th e w a te r s o lu tio n s o f th e a lc o h o l e x t r a c t s o f th e 1933 sam ples a f t e r b e in g red u ced a t 80° C. f o r 30 m in u te s, f i r s t by th e m o d ified S h a f f e r Hartmann t i t r a t i o n method (30) in w hich t i t r a t i o n was c a r r i e d out in th e p re se n c e o f th e p l a n t e x t r a c t and second, by th e V olum etric T h io s u lfa te m ethod (17) in w hich th e cuprous ox id e i s s e p a ra te d by means o f an a s b e s to s mat i n a Gooch c r u c ib le and t i t r a t e d f r e e o f th e p la n t e x t r a c t s . To check f u r t h e r on t h i s p o i n t , th e f i l t r a t e from w hich th e cuprous oxide had been s e p a ra te d was t i t r a t e d a t once by th e M o d ified S haffer-H artm ann m ethod. T itra tio n re s u lts a re p r e s e n te d i n T ables I and I I f o r ap p le and p e a r . These d a ta show c l e a r l y t h a t w ith th e s e e x t r a c t s th e M odified S h affer-H artm an n method g iv e s v a lu e s g r e a t e r th a n th e amounts o f copper reduced w a r ra n t. I n d ic a tio n s a re t h a t t h i s d if f e r e n c e is due t o same sub­ s ta n c e i n th e p l a n t e x t r a c t w hich does n o t reduce th e co p p er, b u t p ro b ab ly behaves a s su g g e ste d by S u lliv a n (34) • T his s u b s ta n c e , w h atev er i t s n a tu r e , seems to be p re s e n t i n l a r g e r amounts i n e x t r a c t s from th e e a r l i e r sam ples, which are more c o lo re d and c o n ta in l a r g e r p ro p o rtio n s o f s k in to f l e s h o f th e f r u i t . The above t e s t was re p e a te d on c le a r e d s o lu tio n s ta k e n from a p p le tis s u e . A p p are n tly some o f th e re d u c in g su b sta n c e s were removed by c le a r in g as th e amounts o f reduced co p p er were s l i g h t l y l e s s . The g r e a t e s t lo s s was in th e S h affer-H artm an n t i t r a t i o n s and shows t h a t about h a l f o f t h i s unknown m a te r ia l was ta k e n from th e s o lu tio n s by c le a r in g . I t would seem from th e s e d a ta t h a t t h i s su b sta n c e i s a s s o c ia te d w ith th e s k in o r pigm ents in b o th a p p le and p e a r f r u i t s . B educing su b sta n c e s on th e 1933 sam ples were d eterm in ed by th e V o lu m etric T h io s u lfa te m ethod, a s d e s c rib e d (1 7 ), e x cep t re d u c tio n was c a r r ie d o u t a t 80° C. f o r 30 m in u tes by means o f a h o t w a te r b a th . - 7 H ardness o f F r u i t s - H ardness o f th e f r u i t s was o b ta in e d on k each sam pling d a te by means o f a P re s s u re T e s te r ( 2 0 ) . A p lu n g e r o f 4 / l 6 in c h d ia m e te r was s u b s t i t u t e d f o r th e r e g u la tio n 5 /l6 in ch one, to re n d e r i t p o s s ib le t o g e t re a d in g s on th e e a r l y h a rd f r u i t s . The p r e s s u re s th u s O btained may be c o n v e rte d , a p p ro x im a te ly , o v er to 5 /l6 p lu n g e r v a lu e s , by a f a c t o r 1*42 when s k in i s removed and 1.35 when s k in i s n o t rem oved. These f a c t o r s were a r r iv e d a t by d e te rm in in g th e p r e s s u re f o r each p lu n g e r on th e same f r u i t s . As th e r a t i o v a r ie s a l i t t l e , b e in g g r e a t e r w ith th e s o f t e r f r u i t s , th e s e f a c t o r s a re on ly ap p ro x im ate, b u t se rv e t o g iv e an e s tim a te o f th e h a rd n e ss o f th e e a r l y f r u i t s . PROCEDURE AND RESULTS D uring th e grow ing seaso n o f 1930, samples f o r chem ical a n a ly s is were ta k e n p e r i o d i c a l l y o f K ie f fe r p e a r , B a r t l e t t p e a r and Wagener a p p le f r u i t s from v ig o ro u s , good p ro d u cin g t r e e s . Changes i n th e amounts o f l i g n o c e ll u lo s e , t o t a l s u g a rs , red u c­ in g s u g a rs , t o t a l p e c tin s and s o lu b le p e c tin s , as p e rc e n ta g e s o f th e d iy w eight were d e te rm in e d . F ig u re 1 compares g r a p h ic a lly th e changes i n l i g n o c e llu lo s e and t o t a l su g a rs i n th e th re e f r u i t s s tu d ie d . A more d e t a i l e d s to r y was d e s ir e d o f th e changes o c c u rrin g in th e K ie f f e r f r u i t s . C onsequently i n 1931 f r u i t s o f K ie f f e r p e a r were sampled e v e ry t h i r d day from June 2 u n t i l J u ly 17 and l e s s f r e q u e n tly t h e r e ­ a f t e r , as lo n g as any f r u i t s rem ained on th e t r e e . As many as 1200 f r u i t s were re q u ire d to f u r n is h enough m a te r ia l f o r a s in g le sample on th e e a r l i e r d a te s and a minimum o f 25 f r u i t s was u sed i n each sam ple. Q u a n tita tiv e d e te rm in a tio n s o f th e c o n s titu e n ts o f th e K ie f f e r p e a r f r u i t s se c u re d d u rin g th e growing seaso n of 1931 a r e p re s e n te d in T able I I I and g r a p h ic a lly in F ig u re 2 . The changes i n lig n o c e llu l o s e , su g a rs and p e c tin s a r e s i m i l a r to th o s e s e c u re d in 1930. Changes i n r e l a t i v e amounts o f lig n o c e llu lo s e in th e K ie f f e r (F ig u re s 1 and 2 ) , c o n s is tin g o f a v e ry ra p id accu m u latio n d u rin g th e f i r s t fo u r weeks a f t e r f r u i t s e t t i n g follow ed by a l e s s r a p id f a l l i n g o f f , arc i d e n t i c a l w ith th o se found by C r i s t and B a tje r ( 7 ) . The accu m u latio n o f li g n o c e l l u l o s e i s accom panied by a d e c re a se i n th e amounts o f t o t a l and re d u c in g s u g a rs , u n t i l a few days b e fo re th e peak o f c o n c e n tr a tio n of lig n o ­ c e l l u l o s e i s re a c h e d . The s u g a r curves th e n in d ic a te a p i l i n g up o f su g a rs c o in c id e n ta l w ith th e d e c re a se in l i g n o c e l l u l o s e . The d if f e r e n c e betw een t o t a l and re d u cin g s u g a rs i s re p o rte d a s su cro se and p e r s i s t s i n r e l a t i v e sm all am ounts. The curve f o r su g ar c o n c e n tra tio n s could alm ost be a r e c ip r o c a l o f th e curve f o r lig n o c e llu lo s e b o th in v a lu e and d i r e c t i o n . The p e rc e n ta g e o f t o t a l p e c tin s d e c re a se s d u rin g th e e a r ly grow ing se a so n , w h ile s o lu b le p e c tin s in c r e a s e . a s l i g h t g ra d u a l in c r e a s e . A fte r th e f i r s t p a r t o f J u ly , b o th show The d if f e r e n c e betw een t o t a l and s o lu b le p e c tin s i s re p o rte d a s p r o to p e c tin ( 6 ) , w hich goes o v er to s o lu b le p e c tin s d u rin g th e l i f e o f th e pear* A gom parison o f Changes in th e Apple and F e a r F r u i t s - That " g r i t c e l l s " a re composed c h i e f ly o f lig n o c e llu lo s e , and t h a t t h e i r forma­ t i o n i s a r e s u l t o f l i g n i f i c a t i o n w hich may be m easured q u a n t i t a t i v e l y by l i g n o c e llu lo s e d e te rm in a tio n s h a s been e s ta b lis h e d by C r is t and B a tje r (7)* As would be ex p ec ted a f t e r c o n s id e rin g t h e i r f in d in g s , th e p e rc e n ta g e o f l i g n i f i e d t i s s u e does n o t in c re a s e in th e " g r i t c e l l " - f r e e Wagener a p p le f r u i t s (F ig u re 1)* A lthough lig n o c e llu lo s e s t a r t s a t a c o n c e n tr a tio n e q u al t o t h a t in th e p e a r , i t d e c re a se s c o n tin u o u sly th ro u g h o u t th e se a so n , ex ­ c e p t f o r a s h o rt p e rio d in J u l y . A ccum ulation o f su g a rs i s n o t d elay ed as in th e p e a r f r u i t s , b u t p ro ceed s a t a u n ifo rm r q te from th e v e ry s t a r t . H e m ic e llu lo se s i n th e K ie f f e r p e a r (F ig u re 2) fo llo w c lo s e ly changes in l i g n i n . A lthough th e changes a re o f a d i f f e r e n t c h a r a c te r in th e a p p le , t h i s r e l a t i o n o f h e m ic e llu lo s e to l i g n i n seems to h o ld , as Widdowson (37) a ls o shows a ra p id d e c re a se in th e p e rc e n ta g e o f hem i­ c e l l u l o s e s i n th e e a r l y l i f e o f B ram ley’ s S e e d lin g a p p le , follow ed by a l e s s r a p id d e c lin e d u rin g th e rem ainder o f th e grow ing s e a s o n . Changes i n s t a r c h c o n c e n tr a tio n , as found by Widdowson (37) and T e tle y (3 5 ), have th e same c h a r a c te r and v a lu e as th o se found i n th e K ie f f e r p e a r . Changes i n th e B a r t l e t t p e a r a r e s im ila r t o th o se in th e K i e f f e r , b u t w ith a g e n e r a l s h o rte n in g o f th e whole p r o c e s s . L ig n o c e ll­ u lo s e cu rv es s t a r t a t a h ig h e r c o n c e n tr a tio n , reach a low er peak e a r l i e r in t h e se aso n and f a l l o f f to a low er l e v e l th a n th o se f o r th e K ie f f e r (F ig u re 1 ) . A lthough t o t a l su g ars show a d e c re a se f o r th e f i r s t two weeks a f t e r f r u i t s e t, i t i s n o t as pronounced as i n th e K ie f fe r and a c cu m u latio n o f su g a rs s t a r t s about 10 days e a r l i e r (F ig u re 1 ) . The g r e a t e r amount o f t o t a l p e c tin s in th e B a r t l e t t seems t o be due t o a g r e a t e r q u a n tity o f p r o to p e c tin . The c h a r a c te r of th e p e c ti n changes is much l i k e t h a t f o r K i e f f e r . An in s p e c tio n o f F ig u res 1 and 2 re v e a ls a c r i t i c a l " p o in t of change" i n th e p e a r f r u i t s where th o s e c o n s titu e n ts which have been ac cu m u latin g suddenly^ d e c re a s e , and th o s e m a te r ia ls which have been de­ c rea sin g . p re v io u s to t h i s tim e , .b eg in t o accu m u late. T his " c o n v e rsio n p o in t" o cc u rs ab o u t t e n days e a r l i e r in th e B a r t l e t t f r u i t th a n in th e K ie ffe r. - 10 There i s a r a p id accu m u la tio n o f s u g a rs , showing a s te a d y in c r e a s e in s u c ro s e , and a g ra d u a l d e c re a se in l ig n o c e llu lo s e from th e v e ry e a r l i e s t sam pling in th e Wagener a p p le . As in th e p e a r f r u i t s , p r o to p e c tin goes o v e r t o s o lu b le p e c tin e a r l y in th e season* The i n ­ c r e a s e o f b o th t o t a l and s o lu b le p e c tin s found i n th e a p p le d u r in g th e l a s t p a r t o f th e grow ing se a so n , d is tin g u is h e s p e c t i n changes i n th e a p p le q u a l i t a t i v e l y from th o se in th e p e a r . Onslow (27) and C r is t and B a t je r (7) show l i g n i n to account c o n s i s t e n t l y f o r about o n e - th ir d o f th e li g n o c e l l u l o s e . These d a ta co­ in c id e w ith t h e i r f in d in g s and, as would be e x p e c te d , l i g n i n changes a r e q u a l i t a t i v e l y th e same a s lig n o c e llu lo s e (F ig u re 2 ). H e m ic e llu lo se ch an g es, p re s e n te d g r a p h ic a lly in F ig u re 2, a r e alm o st i d e n t i c a l w ith l i g n i n changes b o th in amounts and d i r e c t i o n , e x c ep t f o r th e p e rio d o f s ta r c h c o n c e n tr a tio n from J u ly 17 to August 2 4 . D uring t h i s tim e h e m ic e llu lo s e s do n o t d e c re a se as r a p id ly as do th e l i g n i n and m a in ta in a d if f e r e n c e o f ab o u t 4 p e rc e n t of th e d ry w e ig h t. I t may be s i g n i f i c a n t t h a t t h i s o v e r-ra p id d e c re a se in l i g n i n , and slow ­ in g o f th e h e m ic e llu lo s e d e c lin e , c o in c id e n ic e ly w ith th e h ig h concen­ tr a ti o n o f s ta rc h . S ta rc h rem ains i n s i g n i f i c a n t , ( le s s th a h 1 p e rc e n t) u n t i l e a r l y J u ly when i t b e g in s t o accu m ulate r a p id ly , re a c h in g a c o n c e n tr a tio n of 5 p e r c e n t. T h is h ig h c o n c e n tr a tio n i s m a in tain ed u n t i l th e m iddle of A ugust, a f t e r w hich a u n ifo rm d e c lin e o ccu rs and s ta r c h a g a in becomes i n s i g n i f i c a n t about th e m iddle of O ctober. D e x trin s and s o lu b le s ta r c h e s do n o t become im p o rta n t a t any tim e . Thgy d o , how ever, fo llo w th e g e n e r a l tre n d o f th e s ta r c h e s , w ith c o n c e n tr a tio n s v a ry in g from -J- to 1-J- p e rc e n t o f the d ry w e ig h t. - 11 C arbohydrate re s id u e cu rv es are s im i la r t o lig n o c e llu lo s e c u rv es. A nalyses show t h i s re s id u e to be composed alm ost e n t i r e l y o f lig n o c e llu lo s e . R iv ie re and B a ilh a c h e (32) r e p o r t t h a t r ip e n in g , as m easured by 'fche s u g a r c o n te n t, i s p r o g re s s iv e from th e stem end to th e c a ly x end in th e th r e e v a r i e t i e s o f p e a rs s tu d ie d ; nam ely, B eurre Hardy, Angoulepe and Comice. I f t h i s i s t r u e in th e K ie f f e r p e a r , sam pling w hich in c lu d e s th e whole f r u i t would be more r e p r e s e n ta tiv e o f th e su g a r c o n te n t. I t was a ls o d e s ir a b le to e x p re s s c o n s titu e n ts as an a b s o lu te q u a n tity p e r f r u i t . Ac­ c o rd in g ly th e sam ples in 1933, o f K ie f fe r p e a r f r u i t s and Wagener ap p le f r u i t s from the. c o lle g e o rc h a rd , were made up from whole f r u i t s from which th e l o c u l i o f th e c a r p e ls w ith t h e i r c o n te n ts were removed. The av erag e w eight and volume o f th e f r u i t s was d e te n a in e d a t each sam p lin g . The f in d in g s se c u re d in 1933 a re p re s e n te d g r a p h ic a lly in F ig u re s 3 and 4 on a d ry w eight b a s is and in F ig u re s 5 and 6 as a b s o lu te amounts o f th e c o n s titu e n t p e r f r u i t . On a d ry w eight b a s is th e f in d in g s a re i n a c c o rd w ith r e s u l t s o f 1930 and 1931. On an a b s o lu te amount p e r f r u i t b a s i s , an e n t i r e l y d i f f e r e n t p ic tu r e o f th e changes in th e con­ s t i t u e n t s i s o b ta in e d . An in s p e c tio n o f F ig u re s 3 and 5 r e v e a ls th e d e c e p tiv e n ess o f e x p re s s io n s on th e b a s is o f p e rc e n ta g e o f d ry w e ig h t. None o f th e con­ s t i t u e n t s o f th e p e a r f r u i t s d e c re a s e , b u t each one a c t u a l l y in c r e a s e s th ro u g h o u t th e grow ing s e a so n . F ig u re 5 shows c l e a r l y t h a t th e a p p a re n t in c r e a s e and d e c re a se in li g n o c e llu l o s e , when e x p re sse d on a d ry w eight b a s i s , i s due o n ly s l i g h t l y to changes in th e r a te o f accu m u latio n o f l i g n i n and c e l l u l o s e , b u t p r i n c i p a ll y to changes o f th e t o t a l dry w e ig h t. The c h ie f v a r ia b le o f th e d ry w eight i s th e a lc o h o l s o lu b le s u b s ta n c e s , - 12 e s p e c i a l l y re d u c in g s u ^ r s . L ig n in and c e llu lo s e accum ulate f a s t e r d u rin g May and June th a n th e o th e r d ry w eight c o n s ti t u e n t s , th u s showing a g r e a t r e l a t i v e in c r e a s e o f th e s e su b sta n c e s f o r t h i s p e r io d . They c o n tin u e t o a c cu m u la te , b u t a t a l i t t l e slo w er r a t e d u rin g th e r e s t o f th e grow ing s e a so n . However, th e ra p id p i l i n g up o f a lc o h o l s o lu b le sub­ s ta n c e s b e g in n in g ab o u t J u ly f i r s t in c r e a s e s th e t o t a l d ry w eight o f th e f r u i t s so q u ic k ly t h a t a r e l a t i v e e x p re s s io n o f lig n o c e ll u lo s e (F ig u re 3) i n d i c a t e s , u n le s s c a u tio u s ly c o n s id e re d , a sudden and r a p id d e c re a se o f t h is m a te r ia l. D uring May and June th e in c re a s e i n s iz e o f th e f r u i t i s due l a r g e l y to th e fo rm a tio n o f new c e l l s and a t t h i s tim e c e l l w a ll m a te r ia l a c c o u n ts f o r m ost o f th e d ry w eight o f th e f r u i t . A f te r th e l a s t o f Ju n e , in c r e a s e i n f r u i t s iz e is due to ex p an sio n o f th e a lre a d y formed c e l l s and to en larg em en t o f th e i n t e r c e l l u l a r spaces (T e tle y ( 3 6 ) ) . This b e h a v io r would o c c a s io n a p ro g re s s iv e d e c re a se in th e p r o p o rtio n o f c e l l w a ll to c e l l c o n te n ts , th e re b y showing a le s s r a p id in c re a s e in c e l l w a ll m a te r ia ls ( lig n o c e l l u l o s e ) d u rin g th e rem ainder o f th e grow ing se a so n . A lcohol s o l­ u b le m a te r ia ls a re p r e s e n t c h i e f l y in th e v acu o les o f th e c e l l s an d , as w ould b e e x p e c te d , th e l a r g e r th e c e l l s th e g r e a t e r th e p ro p o rtio n o f c e l l in c lu s io n s to c e l l w a ll c o n s ti t u e n t s . T h e re fo re , i t would seem t h a t th e g r e a t in c r e a s e i n d ry w eig h t i s due t o c e l l in c lu s io n s and should be con­ s id e r e d s e p a r a te ly from th e c e l l w a ll c o n s ti t u e n t s . H ardness - H ardness o f f r u i t s in term s o f pounds p r e s s u re as d eterm in ed by th e Government S tandard P re s s u re T e s te r a r e p re s e n te d in F ig u re 8 and T able 9 . - 13 STORAGE STUDIES F or s to ra g e s tu d i e s , f r u i t s were p ick ed a t th r e e d a te s ; th e f i r s t l o t on Septem ber 29, b e fo re th e norm al p ic k in g d a te f o r t h i s v a r i e t y , th e second l o t on O ctober 13, about th e r e g u la r p ic k in g tim e , and th e l a s t l o t on O cto b er 27, l a t e r th a n th e y a r e u s u a lly h a r v e s te d . The f r u i t s w ere p ic k e d in to b a s k e ts and p la c e d in co ld s to ra g e immed­ i a t e l y a t 33° F . d u rin g s to r a g e . Sam ples f o r chem ical a n a ly s e s were ta k e n m onthly N otes on th e c o n d itio n o f th e f r u i t s were made a t tim e o f sam p lin g . Emmett (13) i n an in v e s t ig a ti o n o f changes in p e a r f r u i t s found t h a t " l o s s o f w eight in s to ra g e i s due c h i e f l y to t r a n s p i r a t i o n " . I f t h i s i s th e c a se i n o u r m a te r ia l, th e n we would e x p e c t a lo s s of w a te r and in c re a s e d c o n c e n tr a tio n o f d ry m a tte r , which would, i f u se d as a b a s is o f c a l c u l a t i o n s , show no r e l a t i v e in c re a s e o f m a t e r ia ls . Under th e s e c o n d itio n s , i f c a lc u la tio n s a re made on a f r e s h w eight b a s i s , th e y would show an in c re a s e in c o n s ti tu e n t s . In our c a se , w ith t h r e e d i f f e r e n t p e a r p o p u la tio n s in s to ra g e from O etober to F eb ru ary an in c r e a s e i n c o n c e n tr a tio n o f a l l c o n s titu e n ts i s shown e x c e p t f o r h e m ic e llu lo s e , w h eth er on f r e s h or d ry w eight b a s i s . U ndoubtedly th e c o n d itio n s o f s to r a g e d eterm in e th e m ajor lo s s i n w e i ^ i t . In t h i s study i n 1931-1932 th e p e a r f r u i t s showed a lo s s o f 1-J p e rc e n t o f t h e i r f re s h w eig h t p e r m onth. The d ry w eight c o n c e n tra tio n o f th e f r u i t a c tu a ll y d e c re a se d which in d ic a te d th e m ajor lo s s i n w eight was due to r e s p i r a t i o n and n o t t o t r a n s p i r a t i o n . Of th e th r e e p ic k in g d a te s r e p re s e n te d , O ctober 13 proved t o be th e b e s t f o r s to r a g e . D ete rm in atio n s o f red u cin g m a t e r ia ls , s o lu b le p e c tin , t o t a l p e c t i n s , h e m ic e llu lo s e s and l i g n i n , were made on th e s e f r u i t s d u rin g s to r a g e and a r e p re s e n te d in Table V II and F ig u re 7 . On a p e rc e n ta g e o f th e d ry w eig h t b a s is th e s e d a ta show an in c r e a s e in a l l c o n s ti t u e n t s e x c e p t h e m ic e llu lo s e d u r in g s to ra g e • h e m ic e llu lo s e s t o d e c re a se in a p p le s in s to r a g e . Widdowson (37) found The l a t e r - p ic k e d f r u i t s had a h ig h e r c o n c e n tr a tio n o f su g a rs and low er c o n c e n tr a tio n o f l i g n i n , p e c t i n s , and h e m ic e llu lo s e s . in a l l th e s e r e s p e c t s . The in te rm e d ia te p ic k in g was in te rm e d ia te I t m ight be s i g n i f i c a n t t h a t su g a rs show a sh a rp r i s e fo llo w e d ty a sh arp d e c re a se i n th e e a r l y and l a t e p ic k in g s . The l a s t p ic k in g in d ic a te t h i s b re a k f i r s t and t h i s is the in v e rs e o rd e r o f t h e i r k ee p in g q u a l i t y i n sto ra g e * T his a ls o seems to be th e c a se w ith t o t a l p e c tin s which show a d isa p p e a ra n c e of p e c tin s a s p e a rs g e t o v e r - r ip e and s t a r t b re a k in g down, in B a r tle tt p e a rs . Emraett (13) found t h i s to be th e case In g e n e r a l, chem ical changes d u rin g rip e n in g and breakdown i n s to ra g e a re s im ila r in p e a rs and a p p le s . The h e m ic e llu lo s e s seem to be th e o r i g i n a l so u rce o f r e s p ir a b le m a t e r ia l. The K ie f f e r p e a r f r u i t s p ick ed on O ctober 13 w ith a p r e s s u re o f 14 «8 pounds sk in n ed o r 1 8 ,2 pounds u n sk in n ed , k ep t much b e t t e r in s to r a g e th a n th e l a t e r o r e a r l i e r p ic k e d f r u i t s . I t may be of i n t e r e s t to n o te t h a t th e red u cin g m a te r ia l c o n te n t a t t h a t tim e was 42 p e rc e n t o f th e f r u i t s * d ry w e ig h t, a lth o u g h a s Magness (19) s t a t e s " d if f e r e n c e s in ch em ical co m p o sitio n due t o v a r ia t io n s i n grow ing c o n d itio n s a r e so g r e a t i n r e l a t i o n to th o s e due t o s ta g e o f m a tu rity t h a t any p ic k in g t e s t b a se d on ch em ical co m p o sitio n would prove u n s a ti s f a c t o r y ," - 15 DISCUSSION- AND CONCLUSIONS Assuming th e co u rse o f e v e n ts in th e p ro c e ss o f l i g n i f i c a t i o n to o c c u r a s diagrammed, th e c o n s ti tu e n t s in o rd e r o f t h e i r com plexity would fo llo w th e scheme o u tlin e d hy Onslow ( 2 6 ). F i r s t , some o f th e s u g a r became o x id iz e d t o p o ly u ro n ic a c id s , such as g a la c tu r o n ic and g lu c u r o n ic , w hich may combine w ith c o n d e n sa tio n p ro d u c ts of th e s u g a rs , such a s a ra b in o s e and g a la c to s e , to form p e c tic s u b s ta n c e s . These p e c ti c s u b s ta n c e s , th e n , by d e c a rb o x y la tio n form fiv e -c a r b o n s u g a rs , such as a r a b in o s e , x y lo s e , and some hexoses and u r o n ic a c id s w hich to g e th e r make up th e h e m ic e llu lo s e s . The h e m ic e llu lo s e s may go to l i g n i n , a su b sta n c e h av in g an u n c e r t a i n e m p iric a l fo rm u la . N o rris and S ch ry v er (24) were a b le t o produce some h e m ic e llu lo s e - lik e m a te r ia l by t r e a t i n g a p e c ti n p r e p a r a tio n . C a n d lin and S ch ry v er ( 5 ) , a ls o by t r e a t i n g p e c tin w ith a l k a l i s , se c u re d h e m ic e llu lo s e , s im i l a r i n a l l r e s p e c ts to t h a t i s o l a t e d from wood, and some u n i d e n t i f i e d re s id u e s which th e y s t a t e m ight p o s s ib ly form com binations w ith c e l l u l o s e to produce li g n o c e ll u lo s e . The c e l l u l o s e seems to be composed o f pure g lu co se and p ro b a b ly i s form ed d i r e c t l y by co n d e n sa tio n of g lu c o se (27, p . 6 7 ). L ig n o c e llu lo s e h as a co m p o sitio n o f about 60 p e rc e n t c e ll u lo s e and 40 p e rc e n t l i g n i n (7) (2 7 ). Two g e n e ra l t h e o r ie s as t o th e fo rm a tio n of l i g n i n e x i s t (16, p .4 9 ) ; one, t h a t c e l l u l o s e o f th e c e l l w a ll is c o n v erted d i r e c t l y to l i g n i n o r l i g n o c e l l u l o s e , and tw o, t h a t m a te r ia ls o th e r th a n c e llu lo s e a r e l i g n i n p re c u rso rs. Onslow (26, p . 69) su p p o rts th e f i r s t view "as th e c e l l s in p la n t s grow o ld e r th e w a lls u s u a lly become l i g n i f i e d ; th a t i s , p a r t o f th e c e l l u l o s e - 16 / ■becomes c o n v e rte d t o lig n o c e llu lo s e '* . Konig and Bump (18) a ls o su g g e st th e c o n v e rsio n o f c e l l u l o s e to l i g n i n . The changes i n th e r e l a t i v e amounts o f th e c o n s ti t u e n t s , as in d ic a te d i n F ig u re s 1 , 2 , 3, and 4 , s tr e n g th e n th e h y p o th e sis p re s e n te d in th e l i g n i f i c a t i o n d ia g ra m "• We may im agine th e s u g a rs , which th e le a v e s a r e su p p ly in g t o th e f r u i t s , a r e b e in g c o n v e rte d to p e c tin s and th e n to h e m ic e llu lo s e s and f i n a l l y li g n o c e l l u l o s e . The d a ta show a r e l a t i v e d e c re a s e in s u g a rs d u rin g l i g n i f i c a t i o n in K ie f f e r f r u i t . In th e B a r t l e t t f r u i t w ith a l e s s amount o f l i g n i f i c a t i o n , th e accu m u latio n o f s u g a rs i s r e ta r d e d to a l e s s e x te n t, and in th e a p p le , w ith no l i g n i ­ f i c a t i o n , no ch eck in g o f th e c o n c e n tr a tio n of su g a rs o c c u rs . We would e x p e c t th e p e c t i n s , b e in g in te rm e d ia te p ro d u c ts , to be more u n ifo rm and h e m ic e llu lo s e s , b ecau se o f t h e i r g r e a t e r co m p lex ity , to vaiy more w ith th e end p r o d u c t. (F ig u re 2 ) . T his i s borne out by t h e i r r e l a t i v e c o n c e n tra tio n s A sso c ia te d w ith th e d e c re a s e in lig n o c e llu lo s e i s an i n t e r ­ m ed iate d e c re a se i n h e m ic e llu lo s e s and a sh arp in c r e a s e in s u g a rs . Frcm th e g rap h s showing changes as p e rc e n ta g e o f th e d ry w eight i t i s easy to im agine th e l i g n o c e l l u l o s e b e in g broken down to h e m ic e llu lo s e s and th e n to s u g a rs . Magness (1 9 ), r e f e r r i n g to h is work w ith B a r t l e t t J»ears, co n clu d es t h a t "as f r u i t s r ip e n on th e t r e e , much m a te r ia l o th e r th a n s ta r c h i s c o n v e rte d in to s u g a rs " . Mumeek (22) s u g g e sts t h a t in th e a p p le , h e m ic e llu lo s e s a r e a so u rce o f s u g a r f o r th e m atu rin g f r u i t . C r i s t and B a tje r (7) su g g est a d e s tr u c ti o n o f l ig n o c e llu lo s e and from h i s t o l o g i c a l s tu d i e s , f in d th e c l u s t e r s o f " g r i t c e l l s " a p p a re n tly becom ing s m a lle r as th e r e is more u n lig n i f i e d t i s s u e betw een th e c l u s t e r s . These f in d in g s seem to su p p o rt th e p o s s i b i l i t y o f a b re a k in g down of th e more complex m a te r ia ls t o s im p le r on es, in th e K ie f f e r p e a r f r u i t s d u rin g th e l a t t e r p a r t o f th e grow ing s e a so n . I f th e same d a ta a re p l o t t e d (F ig u re 5) as a b s o lu te amounts o f c o n s tit u e n t s p e r f r u i t f o r d i f f e r e n t d a te s d u rin g th e grow ing se a so n , i t becomes d i f f i c u l t to im agine any o f th e c o n s titu e n ts b re a k in g down. The d a ta show c l e a r l y an in c r e a s e in e v e iy f r a c t i o n . H e m icellu lo se changes a r e alm o st i d e n t i c a l w ith l i g n i n changes (T able I I I , F ig u re 2) and would, i f p re s e n te d as a b s o lu te amounts p e r f r u i t , show th e same in c r e a s e d u rin g th e grow ing s e a s o n . W ith th e s e p a r t i c u l a r d a ta , th e p o s s i b i l i t y o f hemi­ c e l l u l o s e s u p p ly in g su g a r t o th e m atu rin g K ie f f e r p e a r f r u i t is n o t s u p p o rte d . The case may be q u ite d i f f e r e n t in th e a p p le , however, as an in s p e c tio n o f F ig u re 6 re v e a ls a s l i g h t d e c re a se d u rin g th e l a t t e r p a r t o f th e grow ing seaso n in t o t a l amounts o f l i g n i n and c e l l u l o s e . As th e a b s o lu te amount o f l i g n o e c llu lo s e in th e p e a r f r u i t does n o t d e c re a se , b u t a c t u a l l y in c r e a s e s , th e d e s tr u c tio n o f lig n o c e llu lo s e (7) could be acco u n ted f o r by i t s b e in g formed in new p a r ts o f th e f r u i t , as n e a r e r th e p e r ip h e ry , f a s t e r th a n i t i s d e s tro y e d in th e more c o n c e n tra te d a r e a s . The a u th o r i s d o u b tfu l t h a t a c tu a l d e s tr u c tio n o f lig n o c e llu lo s e o c c u rs . An a p p a re n t d e c re a se in s iz e o f th e " g r i t c e l l ” c l u s t e r s may be due to th e c l u s t e r s b e in g pushed f a r t h e r a p a r t as th e f r u i t in c re a s e s in s iz e , due to in c re a s e in s iz e o f in d iv id u a l c e l l s in th e l a t t e r p a r t of th e grow ing se a so n , th u s d i s t r i b u t i n g th e sto n e c e l l s o v er a g r e a t e r a r e a . I f now we c o n s id e r F ig u re 5, i t becomes a p p a re n t t h a t th e r e i s no b a s is f o r th e su p p o rt o f th e s u p p o s itio n t h a t lig n o c e llu lo s e is b e in g c o n v e rte d o v e r to su g a rs o r to any o th e r m a t e r i a l. However, i t does seem q u ite p ro b ab le t h a t th e b u ild in g up o f lig n o c e llu lo s e i s th ro u g h th e s e in te rm e d ia te m a t e r ia ls . - 18 i I t is e v id e n t, t h e r e f o r e , t h a t th e " g r i t t i n e s s " o f p e a rs depends p r i n c i p a l l y on th e e x te n t o f g r i t c e l l fo rm a tio n d u rin g e a r ly s ta g e s o f th e fo rm a tio n o f th e f r u i t and a p p a re n tly i s n o t reduced hy changes ta k in g p la c e i n th e g r i t a g g re g a tio n d u rin g th e l a t t e r p a r t o f th e grow ing se a so n o r d u rin g r ip e n in g . T h is in t u r n means t h a t th e p ro c e ss i s n o t l i k e l y to he m a te r ia lly in flu e n c e d hy c u l t u r a l or h a n d lin g p r a c t i c e s and h e a r s o u t th e s u g g e s tio n o f C r is t and B a tje r (7) t h a t only th ro u g h h i s c h o ic e o f v a r i e t i e s does th e p e a r grow er have any c o n s id e ra b le c o n tr o l o v e r t h i s more o r l e s s o b je c tio n a b le c h a r a c t e r i s t i c of p e a r f r u i t s * ACKNOWLEDGMENT The w r i t e r w ishes t o acknowledge th e a s s is ta n c e and encourage­ ment o f D r. J . W. C r is t i n th e in c e p tio n and e x e c u tio n o f t h i s s tu d y ; th e c o n s tr u c tiv e c r i t i c i s m and su g g e stio n s o f P r o fe s s o r V. R. G ardner i n p r e p a r a tio n o f th e m a n u sc rip t; and th e h e lp f u l su g g e stio n s o f P ro f­ e s s o r C. D. B a ll on chem ical tech n iq u e* - 19 SUMMARY E x is tin g d a ta (and th e f i r s t two y e a r 's r e s u l t s o f t h i s s tu d y ) showed such a trem endous d e c re a se o f th e p e rc e n ta g e o f lig n o c e llu lo s e ( s to n e c e l l s ) accom panied hy an e q u a lly g r e a t in c re a s e o f re d u c in g m a te r ia ls , in m a tu rin g K ie f f e r p e a r f r u i t s , t h a t i t su g g ested t h a t p a r t o f th e lig n o ­ c e l l u l o s e had b een c o n v e rte d to re d u c in g s u b s ta n c e s . I n v e s tig a tio n s of th e s e changes i n th e B a r t l e t t p e a r , a f r u i t in w hich lig n o c e llu lo s e occu rs i n s m a lle r q u a n t i t i e s , showed t h a t as a p e rc e n ta g e o f th e d ry w eight th e li g n o c e l l u l o s e began to d e c r e a s e , w ith a co rresp o n d in g in c r e a s e in red u cin g s u b s ta n c e s , ab o u t 10 days e a r l i e r th a n in th e K ie f f e r . S im ila r s tu d ie s o f th e Wagener a p p le , a f r u i t which c o n ta in s v ery l i t t l e lig n o c e llu l o s e , in d ic a te d d e c re a se s o f lig n o c e llu lo s e and accu m u latio n o f re d u c in g su b sta n c e s o c c u rrin g i n th e f i r s t sam ples ta k e n soon a f t e r p e t a l f a l l . These r e s u l t s s tre n g th e n e d th e s u p p o s itio n t h a t lig n o c e llu lo s e may be c o n v erted to re d u c in g m a te ria ls * D uring th e grow ing seaso n o f 1933, changes in a b s o lu te amounts of th e s e m a te r ia ls i n th e K ie f f e r p e a r and Wagener ap p le were d eterm in e d . These d e te rm in a tio n s show t h a t th e r e was no a c tu a l d e c re a se in lig n o c e ll u lo s e , b u t b ecau se o f th e g r e a t in c re a s e o f a lc o h o l s o lu b le m a te r ia ls , th e p e rc e n ta g e o f li g n o c e l l u l o s e d e c re a se d r a p id ly . The fin d in g s in 1933 in d ic a te s t h a t l i g n i f i e d t i s s u e does n o t b re a k down to form le s s complex m a te r ia ls , in th e s e f r u i t s d u rin g growth* C a lc u la te d changes in co m p o sitio n may be m isle a d in g when p re s e n te d a s p e r c e n ta g e s . T o ta l " g r i t " in p e a r i s n o t reduced d u rin g r ip e n in g , b u t " g r i t t i n e s s " i s masked by th e in c re a s e d amounts o f o th e r c o n s titu e n ts o f th e fru it. - 20 There i s e v id e n c e , how ever, t h a t th e su g ars a re h u i l t up, th ro u g h th e compounds s tu d ie d , t o l i g n i f i e d tis s u e * In s to r a g e , h e m ic e llu lo s e s d e c re a se d more th a n any o th e r c o n s ti t u e n t s and s u g g e sts t h a t th e s e m a te r ia ls may be th e source o f r e s p i r a b l e s u b sta n c e s f o r th e f r u i t a f t e r i t s rem oval from th e tre e * The m o d ified S h affer-H artm an n t i t r a t i o n m ethod, employed f o r d e te rm in in g amounts o f re d u c in g m a te r ia l d u rin g th e f i r s t two y e a r 's s tu d y , was found to g iv e h ig h e r v a lu e s on young p e a r and young ap p le f r u i t e x t r a c t s th a n th e amounts o f copper reduced w a r ra n ts . The h ig h p r o p o r tio n o f s k in to f l e s h in th e sam ples ta k e n when th e f r u i t s were s m a ll i s so c l o s e ly a s s o c ia te d w ith th e s e un w arran ted h ig h v a lu e s t h a t a d s o r p tio n o f th e io d in e re a g e n t by some m a te r ia l in th e s k in i s in d ic a te d . The s u g g e s tio n o f C r is t and B a tje r t h a t th e grow er has l i t t l e c o n t r o l, o th e r th a n v a r ie ty s e le c tio n , ov er th e " g r i t t i n e s s ” of h is p e a r f r u i t s , i s su p p o rte d . - 21 LITERATURE CITED 1* Appleman, C. 0 , , and Conrad, C. M. The p e c tic c o n s titu e n ts o f peach es and t h e i r r e l a t i o n to s o fte n in g o f th e f r u i t * Md* A gr. Exp* Sta* Bui* 283* 2* A rch b ald , H. K* Ann* of Bot* 3* 1926. Chem ical s tu d ie s in th e p h y sio lo g y of apples* 46: 406-460* 1932* Brown, H* T. and M o rris, G. 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Res. 19: 473-501. 20 . and T a y lo r, G. P . 1920. An improved ty p e o f p re s s u re t e s t e r f o r th e d e te rm in a tio n o f f r u i t m a tu r ity , IT. S . B. A. B ep t. C ir . 350. 1925* - 23 (21* M ehta, M. B iochem ical and h i s t o l o g i c a l s tu d ie s on l i g n i f i c a t i o n * Biochem. J o u r. 22. M urneek, A. E . 19: 958-997. 1925, H e m ic e llu lo se as a s to ra g e carb o h y d ra te in woody p l a n t s , w ith s p e c i a l r e fe r e n c e to th e a p p le . P la n t P h y sio . 23. 4 ; 251-265. 1929. N a n ji, D. B ., P a to n , P . J . and L ing, A. B. D e c a rb o x y la tio n o f p o ly s a c c h a rid e a c id s ; i t s a p p lic a t io n t o th e e s ta b lis h m e n t o f th e c o n s t i t u t i o n o f p e c tin s and t h e i r d e te im in a tio n s . J o u r. Soc. Ohem. In d . 44: 253T-258T. 24. N o r r is , P . W. and S c h iy v e r, S. B. P a rt I I I . The p e c tic su b sta n c e s o f p l a n t s . The n a tu r e o f p e c tin o g e n and i t s r e l a t i o n to p e c ti c a c id . Biochem. J o u r . 19: 676-693. 25. 1925. OfDwyer, M. H. 1925. The h e m ic e llu lo s e s . P a r t IV.The h e m ic e llu lo s e s of Beech wood. Biochem. J o u r . 20; 656-664. 26. Onslow, M. W. P la n t b io c h e m is try , Second e d . P r e s s , Cam bridge. 2 7 .--- -------------- ------ The p r in c ip le s o f p la n t b io c h e m is try . P h i l l i p s , T. G. H. H. 29. Cambridge U n iv e rs ity 1923. U n iv e r s ity P r e s s , Cam bridge. 28. 1926. Cambridge 1931. The d e te m in a tio n of su g ars in p la n t e x t r a c t s . A g ri. Exp. S ta . S c i e n t i f i c C o n trib u tio n No. 34‘. P r i e s t l e y , J . H. 1932. The f i r s t su g a r o f p h o to s y n th e s is and th e r o le o f cane s u g a r i n th e p l a n t . Jff. P h y to l. 30. 23: 255-265. 1924. Quisumbing, P . A ., and Thomas, A. W. C o n d itio n s a f f e c t i n g th e q u a n t i t a t i v e d e t e m i n a t i o n of re d u c in g su g ars by F e h lin g s o lu t i o n . E lim in a tio n o f c e r t a i n e r r o r s in v o lv ed in c u r r e n t m ethods. J o u r . Am. Chem. Soc. 43: 1503—1526. 1921. - 24 - 31* R eport o f th e com m ittee on methods of chem ical a n a ly s is f o r the Am erican S o c ie ty o f P la n t P h y s io lo g is ts * P la n t P h y s io l, 1 and 2 , 1927, 32, R iv ie r e , G. e t B a ilh a c h e , G. Re l a p r o g re s s io n de l a m a tu ra tio n dans l e s p o ir e s a c o n te a u . J o u rn a l de l a S o c ie te R a tio n a le d * H o r tic u ltu r e de Prance 4e s e r i e , 20: 306-307, 33, 1919 S h a f f e r , P . A ,, and Hartm ann, A. p . The io d o m e tric d e te rm in a tio n o f co p p er and i t s u se i n su g a r a n a l y s is . J o u r, B io l, Chem, 45: 349-390, 34, S u lliv a n , J . T. 1920, A stu d y o f methods f o r th e d e te rm in a tio n of carb o ­ h y d r a te s . Kies i s , U, o f I , H, 35, T e tle y , U, 1924 ( C ita tio n from 28) The m orphology and cy to lo g y o f th e apple f r u i t , w ith s p e c i a l r e fe r e n c e t o th e Bram ley’ s S e e d lin g v a r i e t y . J o u r , o f Pom. and H o rt, S c i, 36 , T e tle y , XJ. 9: 278-298, 1931, A stu d y o f th e an ato m ical developm ent o f th e a p p le and some o b s e rv a tio n s on th e ,fp e c tic c o n s titu e n ts ” of th e c e l l - w a l l s . J o u r , Pom, and H o rt. S c i. 8: 153-173, 37, Widdowson, E . M. 1930, Chemical s tu d ie s i n th e p h y sio lo g y of a p p le s , X I I I . The s ta r c h and h e m ic e llu lo s e c o n te n t of d e v elo p in g a p p le s . Ann, o f B o t. 46: 597-631. 1932. TABLE I* AVERAGE c . c . OF 0 .1 N ., SODIUM THIOSULPHATE SOLUTION REQUIRED TO TIrpRATE REDUCTION OF FEELING SOLUTION SECURED WITH 50 c . c . OF THE ALCOHOL SOLUBLE EXTRACT OF APPLE FRUITS. ji C D a t e o f S a m p l i f U N C L E A R E D S O L U T S e c I O N n d i S t L h E A R . 5 A c e t E g a t D S O r a e m ] L s p e ) r U T f I 0 N N IL O e O 5 u c 1 ; r a l . c n g * F i r s t T e s -t o T e s t • i t p 0 + 9 © O 49 + 9 o X P i + » P i X © + > CD • P P p P o P r H P h O 3 CD o & + 9 P X CD + 9 CO * X ) O p + 9 - H X i + 9 © + 9 2 3 p © P i C D CD p h TO P P h P p CO X i C O © P i P X + 9 CD CO P i r H o • H . + 9 c o P i + 9 Pi + 9 • H M J J A S a u n u u e g p P p X p - H M © © P i P P h P h • H X x i x i P E 1 49 P 0 © © X 0 0 49 P © © P i r H 4 9 X > J, 3 TO 0 • H a 2 49 P i P i P © 1 O © 3 T O p h [3 p O P H 49 •rH © x © X I E -i P h O 49 © 5 3 3 O r H P . P O P O • H 4 9 © 4 9 P 4 9 ' H E 3 • H i— t E r p P h CO © P i P i O O 4 9 P O • H © 4 9 r H - P -rH • H A i E H . 0 2 . 4 3 . 4 4 4 . 7 2 . 4 2 . 3 . 4 2 . 4 4 . 8 1 0 4 . 5 3 . 0 1 .5 4 . 8 3 . 0 1 . 7 4 . 1 6 6 . 9 5 . 7 1 . 2 6 . 9 5 . 3 1 .6 2 4 7 . 9 6 . 7 1 . 8 . 6 . 8 1 . 0 3 0 8 . 2 7 . 7 7 8. 4 1 4 9 2 5 9 . 9 9 . 10. . 7 . 7 . 7 . 3 8 . 3 • 9 . 9 9 . 4 . 5 . 1 5 9 . 5 - — 7 9 . 7 1 .0 8 3 . 3 . 7 8 11. 14. 5 1 8 8 1 1 .8 -— 1 4 . 3 .2 1 3 . 5 . 3 1 1 .2 1 1 . 7 10. ‘11. 7 4 14.6 1 4 . 0 1 1 3 . 4 3 . 8 *80 grams f r e s h w eig h t f o r each sample 6 .6 1 © P h P h 49 TO P 4 9 X I 4 = - H © 49 © r* > . 9 3 . 2 7 3 . 6 . 9 5 7 . 8 8 9 1 a0 a © - P © P h < H O P © P 4 9 •rH p p 49 P O • H 4 9 > P © © pH © w 1 p © 4 9 P • © X © © © P h P P h 49 2 x i r H - H x l * P Q ) CO A c S O - H X a s x > O P 2 3 49 X X © ! p 1 P r H p P P 3 49 © O TO 1 — 3 P X •rH © 0 P i P r H X © CD 1 P 4 9 P 4 9 • H • X ! 4 9 © © © ® P O ■ rH 4 9 x X © 1 p 0 0 0 ©X I C O P P 4 9 1 8 1 p © P t h P •rH • H r > © p © O 0 r H O i> » x * P © P i a p 2 . 5 © E- 49 P h •rH 49 P i 8 0 3 H t 3 TO © 2 P . 4 2 0 49 P p © - H 4 9 0 © a a0 X I P © TO P h r H X ! © P 4 9 *>■ 0 a P 4 9 © 4 9 © a P P h x i TO 0 p © , o P S r Q X •rH 4 9 I x E H . © P i 4 9 © © • H E - © i c o © PS cd EH P i © 4 9 p p 4 9 O •rH © + 9 ©X O P + 9 P t © x P i 4 9 • H P i P i © « P l P h P O • H . 0 } T O© o 4 9 ® • H r H P h © © P O P TO tx ! 1 4 9 . X p i © . . O ct. P i © 49 3 y t o © 3 - P P O • r l 4 e l © O P 1 — 1 © O r H P i O > - H p © 49 1 0 p © 49 © 7 2 y o +9 CD X CD 4 9 X i X o CO X © P P © a CO o p i r H f« 4 © P © £= • P P i X © X J + 9 4 9 © © 49 49 p H 3 49 o P © © © a © © 2 3 © P O 49 a0 <0 © x O > > p j P i © J P + 9 CD < D r o P •rH X I CD T X i + 9 •rH p P h O O (D + 9 P CD w • X P £ X + 9 O p i © i— 1 o > P H © P . p +9 X 1 — 1 0 0 p © r H P i a I P o o i— l 49 p P CD < H © p © © + 9 •rH 49 0 P 0 p © P P O O ..5 1 . 8 3 . 0 . 7 3 . 5 1 . 8 5 . 9 2 . 4 6 . 6 . 3 a 2 . 0 1. . 0 5 2 . 6 . 7 5 . 6 . 0 6 . . 4 7 . 6 7 . 4 . 5 7 . 9 . 8 . 4 8 .0 . 4 8 . 4 . 9 9 . . . 3 11. 8 9 9 . 2 .4 9 1 1 . 3 .2 11. 6 5 6 5 .4 .4 1 1 .8 11. 0 1 0 . 7 • 4; 11. 1 1 4 . 4 1 3 . 9 1 3 . 6 .2 1 3 . 8 . 3 1 3 . 7 1 3 . 4 1 3 . 1 .2 1 3 . 3 TABLE I I AVERAGE c .c * OF 0 .1 N SODIUM '"’HI0SULFATE SOLUTION REQUIRED TO TITRATE REDUCTIONS OF FEELINGS SOLUTION SECURED WITH 50 c . c . OF THE ALCOHOL SOLUBLE EXTRACT OF PEAR FRUITS. N i t r a ti o n in Copper t i t r a . F i l t r a t e from Reduced Copper ti o n p lu s p re se n c e of V o lu m etrics e p a ra te d from p la n t e x t r a c t p la n t e x t r a c t D ate o f filtra te T h io s u lf a te Sam pling* by S h a f fe r Method t i t r a t e d and t i t r a t e d titra tio n by S h a f f e r by V o lu m etricHartmann Hartmann T h io s u lfa te Metbod. M ethod. M ethod. 20 27 June 4 . 10 16 24 30 7 J u ly 14 25 9 Aug. Sept . 9 9 O ct. 4 Nov. May 1 .6 3 .2 3 .7 3 .1 4 .1 3 .8 3 .7 5 .2 6 .3 7 .3 9 .6 1 5 .8 16.7 1 9 .0 .3 1 .5 2 .2 2 .3 2 .9 3 .0 3 .0 4 .6 5 .4 6 .3 8.7 14.7 16.3 18.6 *80 grams f r e s h w eight per sample •6 1 .5 .9 .9 .6 .4 .2 .2 .3 .3 .1 .1 — - .2 .9 3 .0 3 ,1 3 .2 3 .5 3 .4 3 .2 4 .8 5.7 6. 6 8 .8 14.8 16.3 1 6 .8 • pi OHWNOOHl f ) l O©I O( DOO>( D' ^ | HCft'J, WCOCOHl!00>lOOOHtf) t ‘ HlOCD CO( Oi n ^ *OWOi ( Dt 05DOO^ ^ « DHl f i ^ ^ i ) 0 ) CDCD iNioioto^^tocoto^to^wcoto^Hco^tt^iom-^-^^iO'^^totocococo •rH © ■P -P o o 0) EH p J P 5 ? £ * £ t 2 ? J ^ ! ^ 5 c3 i Q ,-*r“,04lf^ WOl f 3 r", ® t' ' c,,' O O r H H , oc' -cMioC-C0O*O“ OrHr-iCOlNOiHOOOtO?O?OCMO»H1COtOO>23i9:2*, ;ScMi>*oGOH(Dtoosi»i>-.<0oHtH‘ cot>-cocNo»incMi>cMto C MH l N C M« D O O O » C & O « 0 O » O O I > * 0 » < O C Mr H r H t O C Mf H a » O < O C - t O H i i H aOCiOJ^COHOHMWOJoCOMfiW rH BO © © O W O H xi o Pi as -p ^ H H t O W ^ O l C O H W C O l O O O C & C O C O Q C ' - D - C M oinoon^ojoocomiN »Ha»oa»co-o»C‘-I>-IS«O|£ )!fl'^-^!OtOCV|CD!>-^!>!OlDlOlOiO'^lO H H H H H H H H H H H H H H H H r l r l H H H <0' 4, t S [ S ' ^ ( D t O l O ! O L O l Q ^ - l M N W L O O > O O i H ? D O J O N lH O ' 4 < O> ISlO^tOC^tD^OC'tOCO^CO^OOINCOrH^HtOOCOOHHHrHtO H W H t O lO lC O C ^ C 't O ^ ^ N N H CO 0>iOi0«0C0i0 H r H H i H i —I H M H H i—I H H l Oi OOl WOJ' l ' Ot OO' l ODOi l ' i ni OCDOOONCf t ODi nCQOWt ' Ot NOl ^i Ot ' ( •0 5•} t•i OHO»^ # • • «WHCOl • • • • • OO»^ • « l 0i1O• O•l O• ©•I S• D*‘ 5• 5«l O• N*^ ^• a *) l f») H« W• O• >•C •O OCOCOOOl O>©<0' D. r H^i DH- ! j l i noi OEO! O^Oi © GO O -P M -P !>» o Pi «H P -COO>t«*OQtOCJ»C'3tDtOcOcOcQOtOtOrHCVJO»£NiO IS(AitN(DI0C0lO®^t-C0iOCv- r oO5WO' OC; ^WC0 rHWt OC' l ^^MO»G>HCJi W' # ® C O M H « O 0 i n o > l O i O " - n ', f , ‘ ' ' ' * A m , A *r t - u * ‘ r r > r r > _ _ — — COCO-C-~COH<£>- (HMOOl OOmH, O t'!t, OO OO 05iHCv2lOC\2H rHt>H*lOC^Ot>-cO , H4«HHtOH*OHl 0 0O't4O,tM OH t O, O H , 'st, COCOP*-(DtQO » • • • • • « >* o pt l Ol £3i D^OOrHHWWWcO^, ONOOOO>0>l t■ C“i t .«I S. 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KIEFFER PEAR FRUITS IN STORAGE AT 33° F. - DRV WT. BASIS 4® t o si* CM m (N t o 00 o TO © s i— I TO QOOJ HOO^ t * Hc OOt * ©H WM^^COHt O( OOi r l OC» r H H WWWWt O n t Q © TO *H iH O • O U 3 >a)ow^oiH M HOO^^^^^COWHH i—I H TO TO »3 IOCQ«NWTOO(^COWIOO> S3 •H © HO Q ^ H e O O O » O Q [> C O lO H * a O CQ N 03 M H M W ‘ H‘ H‘ r l’ o 3 ^COt>GOH, 0>'CO 3H H l O O O O - C O C O C - t O ^ r H H r l r l H r l i H H t O H 1 (DTOfi Wl OTOOl Ot DWt Oni O a COMWWCOlOTOHIOOH'Wir) toco^iotniominH'^wiMH ° s 5 S i? 60 © TO r l +> & ® CJ 6 © .d O >>o T © £ O C M « 0 i n O t O C M H i C O i n rino«o< oM ® no> o^ O r l O > r | > > H l O W ^ O < J > O O O r l H W N ' 0 0 ® C O O > © TO TO O 1 rH o 3 f l rH QO rH TO O 8 a ■rl rH s .M -P © TO TO ■P m s *P © H © to 4* 4s rH at CO rH i n rH CD TO o o rH CO a O o O CM co • • • • • rH at at CM tO rH a t CN IN H* at CN C- rH H • « '• • rH rH D00 to tn • CO HI 00 ts • rH o i in at co CM rH rH tO • * CM CM O i CM o i CN 00 i n i n CM H rH IN Oi rH rH DCO O CO CM rH O O • 1—1 CM rH O • to CM Hi O * oi i—i o o • CO o rH O • t o rH to CM rH CO o o TO • rH o O o • O at CO CD H* Hi Oi o o r—f CM i n o O o o • • • • hj 3 'tr t o o» CO tO CD CO CM CD iS o i—1 rH CM co ^ CO 01 o> t o • • • • • * • • • • rH H* i n in H« g O o * • in rH O rH ♦ to O rH rH ■ HI CM IN H • oi oi IN CM • cO oi in co • o» Ol CM co • tn IN IN O • H CO o» O rH • rH to rH CM • t> CM IN to • i n CO CD to in o Hi at t o t o t o CO -• » • rH Hi O in to to • g TO TO TO •H •H 9 © Fh TO TO TO P n -P W © TO TO « m P ® rH ^3 TO rH O W rH O A o o rH «*1 1)0 « •H © TO «TO TO tH 1 Cl o « P © TO TO P M TO rH CO C«o • CO o IO CM CM i n rH CO o - o> O o HI at CO CO CM i n o CM t o CM o O o rH CM t o H* co at co CO • • • • • • • • * • -• rH CM CO CO HI * in 00 CO CN CN • oi -p $ >> t 4 i n to CM Hi o !>- i n CO to rH CO CO CO Oi CO • • • * • • • • * • • rH CM CO in IN 00 CO O CO rH CM CO in Hi • O to to 00 • Ol o rH o IN HI O cO H« O IN h i i n O l OI o i rH rH CM CO CM CM rH CM rH > & c a TO e h C C e 3 e « * p • tt) p ( +1 X3 TO © ■Hi CO O d *H d to •Hi M CM to o o • OCO CM O * © © O t rH Q P a r-H t o rH *rj • p o 00 CM rH o • a* t o CO o 4» •H O rH 2 Of u •p rH t o CO IN rH CM rH CM CM « • • CO O IO Cv CO OS a t IO IO IN CM • • • rH CO CO CO IN fc» a t in in CO O o t o co rH CM CO HI cv rH • * « • • rH to rH O o O to to Ol CO CM • to oi rH CM • a t IN t o to 00 to • 1—t Hi rH O • CM IN CM IN * rH rH tO to o rH (O o o o CM co at *• * • rH CM CM CM o» o» o tHIo c> CO CO C D CM o i n O H HI rH IO HI CO CM t o CM o H H CO IN t o * CM o o O o o 1—( CM CO H< t o CN • • • • • • * • • • Hi O O oi • IN tO tO o • rH CM GO a t tO Hi rH o a* 01 a t o • * • i—1 CM t o CN rH o to * Cr 09 00 tJD H O 00 •H *H O d © rcJ ■P P rH O ca © o o d -P to rH -P O © o © ^3 O I d o d •P ra 3 § W W) •rl P &e © d P -p ro •H a£ LO H< rH O • o to rH O • rH in t o o to o CO t o 00 CM t o 00 Hi CO sit i n rH o» O GO GO t o IN 00 CM o» in CN O- GO IN t o o CM CM CO H» tO a t t o • • • CM H» GO CO o? 30 o • CO to CM rH * to to H» CM « IO CO H H* • rH IN CO to * « P to d *r4 O P 4* rH rH O o • IN 00 tO r>*4 • rH 3p • • • • • A* * • H H* o t o H 1 f i © fc- tO © O IN t o t o rH CN a t o CM t o 00 CO CO CJ» * • • • • • • • • • » * 1—1 H CM t o Oi CO 1—1 a OS H «2 H< t o GO rH to at to ♦ • • • • « rH h * t o CO CO rH A o HI to to • o» —1 o t o O CO Hi H« CO £N CO CM • • • * • O CM rH t o CO to CM rH c- tfi t o a t 01 rH CM 1 Ht 00 00 Ol to d O •H in to o CM "T rH rH CM CO ©& 0 $ P CO • -p * t>> 2 H ft -p 00 * ft * ft P ft ft P © o p a i-i co o -P • rj d O O - H ' C R H O - O - O ' C O C - L O Q O O 0»O »C0C»CD C0CD CD G 000CD u ft CQ ^Dl0C»I>OO-^^O a § o U r H s t * o § §> s 1 •H ©S pS • M © o ^ ® w w o o n m o o o tOCO^OCOlOlOlOGOOCOrHW * • • • « « • • • • • • i H ' ^ © O l O WH l © MO l O Cl *S c5 H r H W C O H 1 © ® ^ 5 E** Ph OOlst»OS(DINO>C>JOmtOtOO O O O O O O O O O O O O r H ft CO I—I I—II—I I—! I—I r l I—I I—I rH rH i—I rH rH -p cl O* E0 CM i n « M f l o i o o o o CO 03 H* © W K) 6* H © O O » * » * • * • « * » » Ht O^«OOi H£Nt Ooi Ol O rH rH CQ H* C1- CM sB © o © ■ — I ft (0 •rl 'CJ R* r Q ■P ■ •hag §s 03 .s 5 O ilfiWHWCO'O^OOOOO O I N O i l O C O O r H t O l N O O D l f l C V } • • • * ! * • • * • • * » H W ^ ^ OH W oO^WINCO H H N H 1 CS n xi© d ■g S3 -P © © © •H rH © Pr +» S CD CD CO P O Q M O Or H* £r l ) KH !n O ^ HrH, tn®0»0» W CV2 C\] © fr a 9 h £ • -p W ) ft -P• d ®o < 5 C Q o «H £ TABLE IX HARDNESS OF KIEFFER FEAR AND WAGENER APPLE FRUITS - 1933. D ate o f Sam pling June 10 16 24 30 J u ly 7 14 25 9 Aug. S e p t. 9 9 O c t. K ie f f e r P ea r Mean S .D .# P .E .* * 20.52 22.90 2 4 .1 1 2 3 .44 25.44 2 4 .2 7 2 2 .4 0 20.79 17.29 12.84 1 .5 8 1 .7 7 .38 1 .6 7 1 .6 0 1 .2 1 .35 1.3 0 1 .1 0 .40 1.0 6 1.19 .25 1.12 1.0 7 .82 .23 .87 .74 .26 Wagener Apple C o rre c te d f o r Govf t . Mean P re s s u re T e ste r* 27 .6 30.9 3 2 .5 31 .5 34 .2 3 2 .6 30 .2 28 .0 23.3 17.2 20.04 19.52 20.65 22.31 20.71 20.08 18.38 16.63 12.00 10.80 S .D .# 1.7 5 1.0 6 1 .7 8 2 .1 4 1.4 2 .87 2.43 .80 1.5 5 .79 P .E .* * C o rre c te d f o r Gov*t P re s s u re T e s te r* 1.1 8 .71 1.2 0 1.4 4 .95 .58 1.63 .53 1 .0 4 .53 * Times f a c t o r 1 .3 5 to compare w ith 5/1 6 r e g u la tio n s iz e p lu n g e r. # S tan d ard D e v ia tio n = * * p ro b ab le E r r o r = S . D. x • Summation X' 27 .5 2 6 .3 2 7 .8 3 0 .1 28 .0 2 7 .0 2 4 .8 2 2 .4 16.2 14 .5 0 CO CT» &. rd P )0htm (up ^ «H •H o g rl 0) *n *# ti P P c3 P 0 0 ft o u p 0 a) P«

P CO O o • rH w aS P • •H 0) fe 03 ttfJrH aS _ -P i P 0 o p s 0 0 0 P & •H s r^s 03 P aS P “•H P gt)D § P O P o P 0 r-H P aS 0 P v F ig , 7 , P erc en ta g e change i n c o n s titu e n ts o f K ie f f e r p e a r f r u i t s in s to ra g e a t 33 F , - 1931-32* m o — k a g n e r f lp p / e — ©— Kieffer Pear i— - a v e r a g e fr e s h m e tg h t fr e s h N a g h e r fifo p ie H ardness K ie ffe r P ear wo of 20 27 June July Fig* 8 . Dry w e ig h t, f r e s h w e ig h t, and h a rd n ess o f K ie f fe r p e a r and Wagener ap p le f r u i t s - 1933.