FACTORS RELATED TO THE ISOLATION OF HARD-SEEDED STRAINS OF CRIMSON CLOVER By EDWIN JAMES A THESIS S u b m i t t e d t o t h e S c h o o l o f G-raduate S t u d i e s o f M i c h i g a n S t a t e C o l l e g e o f A g r i c u l t u r e and A p p l i e d S c i e n c e in p a r t i a l f u l f i l l m e n t of the requirem ents f o r th e d e g r e e of DOCTOR OF PHILOSOPHY D e p a r t m e n t o f Farm C r o o s 1948 ProQuest Number: 10008340 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 10008340 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 48106- 1346 approval , c e r t i f i c a t e FACTORS RELATED TO THE ISOLATION OF HARD-SEEDED STRAINS OF CRIMSON CLOVER By EDWIN JAKES A-qtor o v e d : Major P r o f e s s o r Head o f D e p a r t m e n t Aooroved: Date iii TABLE OF CONTENTS CHAPTER PAGE I. INTRODUCTION ................................................................................ 1 II. REVIEW OF LITERATURE ........................................................... 3 III. EXPERIMENTAL PROCEDURE ...................................................... 9 I.ANATOMY OF THE SEED C O A T .......................................... 9 M e t h o d s and M a t e r i a l s ............................................... 9 R esu lts and D i s c u s s i o n .......................................... 10 II.EFFECT OF INBREEDING .................................................... 15 M et h o d s and M a t e r i a l s .......................................... 15 R esu lts .......................................... 1? and D i s c u s s i o n III.PHYSIOLOGICAL FACTORS ............................................... 68 SEED S I Z E ............................................................................... 6 8 M e t h o d s and M a t e r i a l s .................................... 68 R e s u l t s and D i s c u s s i o n .................................... 69 ......................................................... 71 MOISTURE SUPPLY M e t h o d s and M a t e r i a l s ................................... 71 R e s u l t s and D i s c u s s i o n .................................... 72 HUMIDITY.....................................................................................75 M e t h o d s and M a t e r i a l s .................................... 75 R e s u l t s and D i s c u s s i o n .................................... 78 LIGHT I N T E N S I T Y ................................................................81 M eth od s an d M a t e r i a l s .................................... 81 R e s u l t s and D i s c u s s i o n .................................... 81 FLO'OERING S E Q U E N C E ........................................................... 83 iv CHAPTER PAG-E M et h o d s and M aterials .................................... 83 R esu lts D i s c u s s i o n ................................... 83 .......................................................... 91 and NUTRIENT LEVELS M e t h o d s and M aterials . . . . . . . . 91 R e s u l t s and D i s c u s s i o n .................... ............... MOISTURE CONTENT OF S E E D .............. IV. V. VI. 97 M et h o d s and M aterials ................................... 97 R e s u l t s and D iscu ssio n . . . . . . . 98 SUMMARY AND CONCLUSIONS . . . LITERATURE CITED APPENDIX A. 93 1 ..........................100 .........................................104 ............................................................................. 108 G-ERl.ilNATION OF CRIMSON CLOVER PLANTS SELFED IK 1 9 4 4 108 B. RELATIVE HUMIDITIES AT ATHENS, GEORGIA DURING PERIODS OF SEED DEVELOPMENT OF CRIMSON C L O V E R ......................................................... 115. C. RELATIVE HUMIDITIES IN CHAMBERS DEVISED FOR HUMIDITY S T U D Y ............................................... 1 15 D. GERMINATION OF CRIMSON CLOVER STRAINS AT EXPERIMENT AND TIFTON, GEORGIA IN 1 9 4 6 and 1 9 4 7 ............................................................... 116. E. MEAN TEMPERATURES AND RAINFALL AT EXPERIMENT AND TIFTON, GEORGIA DURING PERIODS OF SEED DEVELOPMENT IN CRIMSON CL O V ER ............................................................................... 116 LIST OF TABLES TABLE PAGE I. PERCENT HARD SEED III FORTY RANDOM PLANTS . . 13 II. MEAN GERMINATION OF PLANTS SELFED IN 1 9 4 4 . 19 III. GERMINATION OF SOFT-SEEDED S j PLANTS SELECTED AS PA RENTS...........................................................................22 IV. GERMINATION OF HARD-SEEDED PLANTS SELECTED AS S-j- P A R E N T S .............................................. V. . . . . GERMINATION OF PROGENY OF SOFT-SEEDED S P A R E N T S .................................................................................. VI. 24 26 GERMINATIuN OF PROGENY OF HARD-SEEDED S j P A R E N T S ................................................................................31 V II. GERMINATION OF SOFT-SEEDED PLANTS SELECTED AS S 2 P A R E N T S ................................................................ 37 V III. GERMINATION OF HARD-SEEDED PLANTS SELECTED PA REN TS ...................................................................39 AS S 2 IX. GERl.il.'! ATI ON OF PROGENY OF SOFT-SEEDED Sg P A R E N T S ................................................................................41 X. GERMINATION OF PROGENY OF HARD-SEEDED Sg PARENTS XI. . . . . . 47 GERMINATION OF SOFT-SEEDED S , PLANTS SELECTED o AS PARENTS . . . . . XII. ......................................................... .................................................... GERMINATION OF HARD-SEEDED S o PLANTS SELECTED AS PA RE NT S.......................................................................... 55 53 vl TABLE :i i i P.-' . GERMINATION OF PROGENY OF SOFT-SEEDED S , 3 P AhENTS......................................................................................... XIV. 58 GERMINATION OP PROGENY 01 IIABD-SEEDED S 3 PARENTS........................................................................................ XV. j- ii 62 LIEAIT GERMINATION OF SOFT, AND HaHD-SEEDED PARENTS AND THEIR PROGENY.......................................... 66 GERMINamION Oi 1 CnlUSON CLOVER AS AFFECTED X V II. X V III. BY S I 2 E OF SEED.................................................................... 69 ANALYSIS OF DATA IN TABLE X V I ..................................... 70 EFi'ECT OF HOIST IRE SUPPLY ON SEED SIZE AID PE RHEA' I L I T Y ......................................................................... 73 EFFECTS Os' HUI.IIDITY ON SEED SIZE AID GERMINATION.............................................................. XX. 79 EFFECT OF LIGHT INTENSITY Cl! SEED S I Z E AID PERI IDAI I LIT Y ................................................ ........................ XXI. 82 EFFECT 01 HEAD SEQUENCE ON SEED SIZE AID PRRIvIEA I L I T Y Oi- SEVENTY-FIVE PLAIDS IN 1946 XXII. .............................................................................................. EFPECT OF HEAD SEQUENCE PERMEABILITY 0 . ON SEED SIZE AND SEVENTY-FIVE PLANTS IN 1 9 4 7 .............................................................................................. X X III. XXIV. yyu DESIGN 01 84 NUTRIENT LEVEL EXPERIMENT..................... EFFECT Oi NUTRIENT LEVELS ON PERMEABILITY. ANALYSIS OF *'a RIANCE Oi' DATA IN TABLE XXIV . . 87 92 93 94 vli TABLE XXVI. PAGE CALCIUM CONTENT OF PLANTS AS AFFECTED BY LEVELS OF APPLICATION ............ XXVII. . ■........ 96 AIR SPACE BETWEEN COTYLEDONS AND SEED COAT AS INFLUENCED BY MOISTURE CONTENT X X V I II . EFFECT OF MOISTURE . . . . CONTENTON PERI,IEABILITY. 98 99 LIST OP FIGURES FIGURE 1. PAGE C r o s s S e c t i o n View T h r o u g h t h e S e e d C o a t o f C r i m s o n C l o v e r .............................................................12 2. G e rm in a tio n R ate o f T o ta l P la n t P o p u la tio n S e l f e d I n 1 9 4 4 .................................................................... 3. R ate of G erm in atio n of S o f t- s e e d e d P a r e n t s ......................................................... . ................................2 3 4. G e r m i n a t i o n R a t e o f H a r d - s e e d e d S^ P a r e n t s . 5. R ate o f G erm in atio n o f Progeny of S o f tSeeded 6. 20 P arents . 25 ..................................................... 30 G erm in atio n R ate of rro g e n y o f H ard -se e d e d S-]_ P a r e n t s . .................................... 35 7. G e r m i n a t i o n R a t e o f S o f t - s e e d e d Sg P a r e n t s . . 38 8. G e r m i n a t i o n R a t e o f H a r d - s e e d e d Sg P a r e n t s . • 40 9. Rate of G erm in atio n o f Progeny o f S o f t- s e e d e d ................................................................ 45 S0 P a r e n t s 10. R ate of G erm in atio n o f Progeny o f H ard -seed ed S 0 P a r e n t s ...................... .............................................. ..... . 52 11. G erm in atio n R ate o f S o f t - s e e d e d S7 P a r e n t s . o . 54 12. G e rm in a tio n R ate o f H a r d - s e e d e d S^ P a r e n t s . . 56 13. G e rm in a tio n Rate of th e Progeny o f S o f t- 14. s e e d e d S„ P a r e n t s ............................................................. 61 3 G e m i n a t io n R ate o f th e Progeny o f h a r d s e e d e d S% P a r e n t s ................................................ 05 ix 1 1 G j rtS 15. P A G ii« G erm in atio n of ^h ree P a r e n t a l G e n e ra tio n s a n d T h e i r •‘• " r o g e n y ..................................................................... 67 16. D i a g r a m o f H u m i d i t y C h a m b e r s ..................................................77 17. R e g r e s s i o n b i n e o f S e e d I m p e r m e a b i l i t y on b e a d S e q u e n c e ........................................................................ 18. 85 T e m p e r a t u r e R a n g e s f o r 1946 a n d 194 7 D u r i n g S e e d D e v e l o p m e n t o f 6 r i rns0n C l o v e r ........................... 8 8 19. R ain fall D istrib u tio n f o r 1946 a n d 19 47 D u rin g Seed D evelopm ent o f Crim son C lo v e r . 89 INTRODUCTION Since i t s and i t s s u b s e q u e n t d i s t r i b u t i o n by t h e P a t e n t O f f i c e Crimson c l o v e r in gly i n t r o d u c t i o n in t o the U n ited S t a t e s in 1885, ( T r i f o l l u m i n c a r n a t u m L « ) h a s become i n c r e a s ­ im p ortan t. It is w i d e l y grown a l o n g t h e A t l a n t i c c o a s t a l p l a i n s and t h e p i e d m o n t s e c t i o n s S tates. in 1818 In G eorgia i t im a te ly 152,000 a cres fo ra g e in the f a l l of th e S o u th e a s te r n ranks as the s e c o n d legume, seeded fo r s o i l o f 1947 w ith approx­ im p r o v e m e n t and w i n t e r (2). I t h a s b e e n p o p u l a r a s a g r e e n manure c r o p b u t w i t h stim u la ted i n t e r e s t in w inter grazing, b ein g seeded fo r t h is purpose. early s p r i n g , and i t s a b ility Its i n c r e a s i n g a c r e a g e s are g r o w t h i n t h e f a l l and t o make some g r o w t h d u r i n g warm p e r i o d s In th e w in t e r g i v e s i t a very h igh carrying ca p a c ity . I t h a s an a d d e d a d v a n t a g e i n b e i n g one o f t h e f e w w i n t e r legum es In the South th a t p rod u ces la r g e y i e l d s Even t h o u g h i t h a s many d e s i r a b l e its b le. of v i a b l e q u a lities seed. as a crop a c c e p t a n c e h a s n o t b e e n a s g e n e r a l a s w o u ld seem d e s i r a ­ F ailu res in f u r th e r attem pts o b ta in in g stands in the f a l l to seed the crop. has been a t t r i b u t e d to a v a r i e t y poor seedbed p rep a ra tio n , The f a i l u r e tend to d isco u ra g e to o b t a in sta n d s of c a u s e s ,c h i e f o f which a re in ad eq u ate i n o c u l a t i o n , p e r c e n ta g e s of hard seed ( 1 ) . Kephart (13) states and low t h a t crim son -2 - c l o v e r p r o d u c e s p r a c t i c a l l y no h ar d s e e d , 90 p er c e n t i n 2 d a y s. o f te n germ inating G erm ination o f s o f t s e e d on s o i l s low i n m o i s t u r e l e a d t o a h i g h m o r t a l i t y when h o t f a l l d a y s dry out the s o i l . o f hard seed i s Most s o u t h e r n a g r o n o m i s t s a g r e e t h a t t h e l a c k the g r e a te st s in g le factor lim it in g plan t su r v iv a l. The f a i l u r e t o v o l u n t e e r when i t i s used as a grazin g c r o p i s a l s o a t t r i b u t e d t o lo w s e e d i m p e r m e a b i l i t y . p rob ab ly w e ll founded b eca u se i t This i s i s a common o c c u r r e n c e t o f i n d a h e a v y s t a n d o f c l o v e r s e e d l i n g s two w e e k s a f t e r s e e d r i p e n when f o l l o w e d by f r e q u e n t r a i n s . tio n s a ll It the With few e x c e p ­ t h e s e s e e d l i n g s d i e o u t d u r i n g t h e summer m o n t h s . appeared t h a t t h e s o l u t i o n t o th e problem o f i n s u r ­ i n g a s t a n d o f c r i m s o n c l o v e r w h i c h w o u ld v o l u n t e e r o v e r fa ir ly lon g p erio d s r e so lv e d i t s e l f i n t o th e developm ent o f a s t r a i n w h i c h w o u l d p r o d u c e hard s e e d i n p r o p o r t i o n s a p p r o a c h ­ in g th o s e o f o th e r legum es, abundance o f su c h . l o n g r e c o g n i z e d a s p r o d u c i n g an T herefore, t h e work r e p o r t e d h e r e i n was begun i n 1942 w i t h t h e i n i t i a l o b j e c t i v e o f i s o l a t i n g l i n e s o f c r im s o n c l o v e r w h ich would meet t h e n e e d s o f t h e South f o r a hard se e d e d v o l u n t e e r i n g s t r a i n . -3REVIEW OF LITERATURE The s t r u c t u r e o f t h e s e e d c o a t s an a p o s s i b l e r e a s o n s f o r i m p e r m e a b ility o f th e se e d s of th e Legum inoseae have i n t r i g u e d scie n tists certa in fir st for cen tu ries. ceils M alohius in 168? ( 2 2 ) , a f t e r whom i n t h e s e e d c o a t were named, was a p p a r e n t l y t h e t o study seed coat s tr u c tu r e in t h i s fam ily. Most o f t h e in v estig a tio n s o f impermeable s e e d s o f c u l t i v a t e d legu m es have been c o n f in e d , alm ost e x c l u s i v e l y , t o s w e e t c l o v e r and a l f a l f a . W ith few e x c e p t i o n s e f f o r t s have been d i r e c t e d toward d e t e r m in ­ i n g t h e n a t u r e o f i m p e r m e a b i l i t y and m e t h o d s o f b r e a k i n g t h i s t y p e o f d o rm a n cy . Pamrael ( 2 2 ) presented a l l in h is the t h e o r i e s com prehensive r e v ie w of l i t e r a t u r e t o date con cern in g the reason fo r I m p e r m e a b ility in th e Legum inoseae. as O p i n i o n s were d i v i d e d t o w h e t h e r i m p e r m e a b i l i t y was c a u s e d by an e x t e r n a l l a y e r o f c u t i n or th e " lig h t lin e ." He f o u n d t h a t t h e l i g h t lin e was p e r m e a b l e t o w a t e r and a t t r i b u t e d i m p e r m e a b l e p r o p e r t i e s to th e unequal l a y e r of c u t i n surrounding th e se e d . H is i n v e s t i g a t i o n s c l u d e d t h o s e o f Red C l o v e r o f t h e anatomy o f l e g u m e s e e d s i n ­ (T. p r a t e n s e L . ) and B u f f a l o C l o v e r (T . r e f l e x u m L . ) ^ b u t n o t o f c r i m s o n c l o v e r . crib ed three separate la y e r s of c e l l s fir st In t h e s e he d e s ­ in the seed c o a t , b e in g the m a c r o s c l e r i d s , o f t e n r e f e r r e d t o as the "M alohigian" -4- c ells, resem bling p a llis a d e cells in arrangem ent. On t h e o u t e r p a r t o f t h e s e c e l l s which he i n c l u d e d as a p o r t i o n o f t h e o u t e r c e l l w a l l was a w e l l d e f i n e d c u t i c u l a r i z e d l a y e r o v e r w h i c h was f o u n d an u n e q u a l l a y e r of c u tin . The r a d i a l w a l l s of th ese c e l l s w er e f o u n d t o be g r e a t l y but u n e v e n ly t h i c k e n e d g i v i n g t h e c e l l c a v i t y an i r r e g u l a r a p p e a r a n c e w i t h p o r t i o n s e x t e n d i n g i n t o r a d ia l w a lls. The u n e v e n t h i c k e n i n g , the a c c o r d i n g t o Pammel, c a u s e s a r u p t u r e o f t h e o u t e r c e l l w a l l and l a t e r d e v e l o p ­ m ent o f t h i s la y e r b r in g s about a d e p o s i t i o n of c u t i c u l a r i z e d m a t e r i a l i n t h e s e r u p t u r e s which he termed pore c a n a l s . He d e sc r ib e d the c e l l c a v i t i e s of the m a c r o s c le r id s as b e in g fille d tan in , w ith p r o t e in g r a in s , pigm ents, and an o c c a s i o n a l l a r g e chromophore. The n e x t l a y e r v e r i f i e d by Pammel a r e t h e o s t e o s c l e r i d s or h o u r -g la ss cells. T h e s e w er e d e s c r i b e d a s t h i c k - w a l l e d c e l l s w ith lo n g it u d in a l c a n a ls . g ives H is d e s c r i p t i o n o f t h e s e c a n a ls the im p ressio n th a t he r e f e r s to the p r o j e c t io n s outer c e l l w a ll in to the c e l l cavity. of the He c a l l e d t h e n e x t l a y e r o f com pressed parenchymous t i s s u e the n u t r i e n t l a y e r b eca u se in th is t i s s u e was f o u n d t h e v a s c u l a r s y s t e m b e f o r e The l a s t endosperm. cells, two l a y e r s its co lla rse. o f c e l l s he i n c l u d e d under th e The o u t e r m o s t o f t h e s e were d e s i g n a t e d a s a l e u r o n e w i t h t h i c k w a l l s ^a.nd c o n t a i n i n g f a t s and p r o t e i n g r a i n s . The a l e u r o n e was f o u n d t o be u n d e r l a i n by c e l l s w i t h t h i n -5 - prim ary w a lls w ith a t h ic k e n in g o f r e s e r v e W lnton (30) cellu lo se* d id n o t c o n s id e r crim son c l o v e r i n h i s g a t io n s but h i s d e s c r i p t i o n of red c lo v e r i s in v esti­ in agreement w i t h t h a t o f Pammel* Hamly ( 5 ) ity dem onstrated the tru e nature of im perm eabil­ i n M e l i l o t u s a l b a and n o t e d t h a t w a t e r a b s o r p t i o n by s o f t u n s c a r i f i e d s e e d was by way o f t h e s t r o p h i o l e . The same s t r u c t u r e was f o u n d t o p e r f o r m i n t h i s manner i n T. T. arvense, T. h y b r i d u m , and T. p r a t e n s e . agrarium , H is o b s e r v a t i o n s on t h e f u n c t i o n o f t h e s t r o p h i o l e i n M e l i l o t u s w er e c o n f i r m e d b y M a r t i n and W ya t t ( 1 7 ) . Anatom ical s t u d ie s of clover seeds show no s t r u c t u r e s a n a lo g o u s t o th e con es or M a lp h ig ia n caps of M e li l o t u s * N elson of (21) and W h ite (29) a g r e e w i t h Pammel t h a t i m p e r m e a b i l i t y some l e g u m e s e e d s c a n be a t t r i b u t e d t o a waxy c o a t i n g on the e x te r io r of the seed. b ility of the true c lo v e r s . T h i s w o u ld e x p l a i n t h e im per mea ­ E arlier th eo ries v ie w have a lr e a d y been m entioned (2 2 ). A survey of the l i t e r a t u r e r e v e a ls ga tion s of .lim ited scope in t o the p o s s i b l e im perm eability. Lute (15) o v e r a p e r i o d o f tw o y e a r s , groups. supporting t h is only t h r e e i n v e s t i ­ in h eritan ce of as a r e s u l t of her i n v e s t i g a t i o n s cla ssifies a lfa lfa in to three One g r o u p p r o d u c e d a p p r o x i m a t e l y t h e same p e r c e n t a g e o f h a r d s e e d i n two c o n s e c u t i v e y e a r s . A n o t h e r a much l o w e r , -6 and t h e t h i r d a nuch h i g h e r p e r c e n t a g e t h a n t h e p a r e n t s . She p o s t u l a t e s a g e n e t i c d i f f e r e n c e w h i c h may h e o b s c u r e d by c l i m a t i c f a c t o r s . H arrington ( 6 ) d e f i n i t e l y is s ta t e s th at hard-seededness not a v a r i e t a l c h a r a c t e r i s t i c o f red c l o v e r . The p e r c e n t ­ a g e o f h a r d s e e d p r o d u c e d by p r o g e n y was u n a f f e c t e d w h e t h e r t h e p a r e n t p l a n t s r a n 95 p e r c e n t h a rd s e e d o r 5 p e r c e n t . P e iters (24) s t u d i e d t h e s e a s o n a l p r o d u c t i o n o f h ar d s e e d i n f i v e p l a n t s o f L e s p e d e z a s e r i c e a and f i v e y e a r s o f s e le c t io n for s o ft l i n e s r e su lte d i n no p r o g r e s s . D escendants o f p l a n t s which produced a h ig h p e r c e n t a g e o f perm eable un­ h u l l e d s e e d , w e r e no b e t t e r in p e r m e a b ility than the a v era g e. I t may be n o t e d t h a t t h e e x p e r i m e n t s c i t e d a b o v e c o n ­ c e r n e d o n l y p e r e n n i a l s and w i t h t h e e x c e p t i o n o f H a r r i n g t o n ' s work wa s c o n f i n e d t o v e r y s m a l l p o p u l a t i o n s . effort A p p a r e n t l y no h a s b e e n made t o p r o v e or d i s p r o v e g e n e t i c d i f f e r e n c e s i n a n n u a l s by s e l f i n g and s e l e c t i o n o v e r a p e r i o d o f y e a r s . As i n d i c a t e d a b o v e , a ll i n v e s t i g a t o r s n o t e d a marked d i f f e r e n c e i n h a r d s e e d p r o d u c t i o n from y e a r t o y e a r , in v estig a tio n s but t o c o r r e l a t e c l i m a t i c and p h y s i o l o g i c a l f a c t o r s w i t h s e e d p e r m e a b i l i t y have been v e r y l i m i t e d . Lute (15) f o u n d t h a t a l f a l f a a t an a l t i t u d e o f 7 , 0 0 0 f e e t p r o d u c e d 1 5 p e r c e n t more h a r d s e e d t h a n t h e same v a r i e t y grown a t 6 , 2 0 0 f e e t . were not rep orted . T e m p e r a t u r e and m o i s t u r e r e l a t i o n s h i p s W eath er r e c o r d s ( 4 ) the higher a l t i t u d e r e c e iv e d , annually, s how , however, 7 . 6 i n c h e s more that p recip ita tio n than the low er a l t i t u d e s . The h i g h e r a l t i t u d e a l s o had a 6 . 2 d e g r e e lov/er J u l y t e m p e r a t u r e . e n c e o b s e r v e d may h a v e b e e n due t o a l t i t u d e , tem perature, h u m id ity or to H arrington hard (6 ) The d i f f e r ­ p recip ita tio n , th eir in te r a c tio n s. d i s c o u n t s s o i l a s h a v i n g any e f f e c t s e e d p r o d u c t i o n ; p l a n t s on c l a y s o i l s and s a n d y s o i l s p r o d u c e d s e e d w i t h t h e same d e g r e e o f h a r d n e s s . s i x y e a r s l e d him t o c o n c l u d e t h a t l a r g e s e e d a r e p r o d u c e d by r e d c l o v e r , a lsik e on T e s ts over Q u a n tit ie s o f hard clover, and w h it e s w e e t c l o v e r r e g a r d l e s s o f s e a s o n . w hite clover, Samples o f s e e d grow n fro m t h e same o r i g i n a l l o t p l a n t e d a t s e v e n l o c a t i o n s in the U nited S t a t e s a l l seeds. c o n t a in e d a l a r g e p e r c e n ta g e of hard H i s o b s e r v a t i o n s on s e a s o n and c l i m a t e do n o t seem t o be in f u l l accord w ith h i s s t u d y on y e a r l y v a r i a t i o n a s p r e v io u s ly quoted. H iltn e r & K inzel ( 8 ) r e p o r t e d t h e i r o b s e r v a t i o n s on t h e h a r d n e s s o f t h e s e e d o f s e v e r a l l e g u m e s and s t a t e d t h a t r e d c l o v e r g e n e r a l l y c o n t a i n s from f i v e to ten per cen t of hards e e d s but i n some y e a r s t h e p r o p o r t i o n may run a s h i g h a s 60 p e r c e n t . They attrib u te the d i f f e r e n c e betw een y e a r s to weather v a r i a t i o n s . The n e e d f o r h a r d s e e d i n c r i m s o n c l o v e r i s by t h e f a c t is s o w n. em phasized t h a t b e t t e r s t a n d s a r e o b t a i n e d when u n h u l l e d s e e d U n h u l l e d s e e d g e r m i n a t e more s l o w l y t h a n h u l l e d seed. -8- S titt (27) f o u n d t h a t h u l l e d s e e d a b s o r b e d 18 p e r c e n t more w a t e r in 8 hours b lo ttin g paper. t h a n u n h u l l e d s e e d when p l a c e d on On a m u l c h e d a r e a u n h u l l e d a 25 p e r c e n t b e t t e r sta n d than h u lle d . seed gave e q u a l s ta n d s w ith l a t e no s e r i o u s d a m a g e , if the rain s. seed produced H u l l e d a n d un; u l l e d I.IcKee ( 2 0 ) rep o rts s e e d s w e l l e d and d r i e d o u t , out / i f th e rad icle had em erged, i n j u r y i n c r e a s e d w ith the le n g th of tim e o f d r y i n g . S ev eral farm ers m ain tain in g 20 y e a r s . in th e s o u th e a s t have a s t a n d o f c r i m s o n c l o v e r f o r p e r i o d s o f 18 t o T his seed i s m ost p ro m is in g o f th e s e r e p o r te d as usin g h a rd . name o f D i x i e . is R e c e n tly the s t r a i n s w ere b u l k e d and r e l e a s e d by th e G eorgia A g r i c u l t u r a l E xperim ent S t a t i o n it succeeded in (28) u n d e r th e I n view o f the i n v e s t i g a t i o n s w in c h f o l l o w d o u b tf u l w hether th e y are j u s t i f i e d v a r ie ty as hard seeded. in classing th is -9 - EXPERIMENTAL PROCEDURE Three p h a ses r e l a t i n g to im p erm ea b ility are re p o r te d h erein , nam ely: breeding, in th is t h e anatomy o f t h e s e e d c o a t , and p h y s i o l o g i c a l factors. e f f e c t of in - They w i l l b e c o n s i d e r e d sequence. I. ANATOMY OF THE SEED COAT M e t h o d s and M a t e r i a l s The m o s t s a t i s f a c t o r y m ethod f o u n d t o p r e p a r e s e e d s f o r s e c t i o n i n g was t o g l u e t h e e n d s t o s m a l l d e p r e s s i o n s i n w o o d e n b l o c k s and t h e n imbed them i n p a r a f i n . S e c tio n s 4 to 5 m i c r o n s i n t h i c k n e s s w e r e s u c c e s s f u l l y made w i t h a s l i d i n g m icrotom e. S e e d c o a t s e c t i o n s w e r e rem oved fro m t h e p a r a f i n under a b in o cu la r s t e r o s c o p ic m icroscop e, o r by d r o p p i n g t h e sectio n s p a p e r and d i s s o l v i n g in to a corner o f a porous f i l t e r t h e p a r a f i n w i t h c a r b o n t e t r a c h l o r i d e or c a r b o n b i s u l f i d e . Seed c o a t s e c t i o n s were th en t r a n s f e r r e d to s l i d e s w ith a m o isten ed n e e d le . M e t h y l e n e b l u e was f o u n d t o be a s a t i s f a c t o r y fo r cursory exam ination. q u ired fo r t i s s u e More s p e c i f i c id en tifica tio n . t e s t s u s e d by Hamly ( 5 ) stain i n d i c a t o r s were r e ­ With on e e x c e p t i o n t h e were f o llo w e d . -1 0 R esu lts and D i s c u s s i o n E xcept f o r m inor d i f f e r e n c e s t h e o b s e r v a t i o n s made w e r e i n a c c o r d w i t h t h o s e o f Pammel ( 2 2 ) The c o m p o s i t i o n o f t h e seed c o a ts , is essen tially M elilo to u s alb a the fin a lly Is acid s. c o lla p s e d parenchym a, su b c itic u la r in so lu o le in e ith e r S u lfu ric acid , the a le u r o n e , iig u re The c u t i c l e 1 illu strates on C r i m s o n c l o v e r layer are w ell d efin ed . concen trated however, T reatm ent f o r l a y e r down t o t h e l i g h t th is su lfu ric does p e n e tr a te p eriod d isso lv es lin e. It The c u t i ­ or h y d ro c h lo ric the c u t i c l e . is the cu ticle ness. th e lay er, is not p e n e tra te d The a u s e n c e and w i t h S u lfuric sectio n s leav es th ick ­ by a 1 p e r c e n t s o l u t i o n o f of a suberized area c l o v e r w ould s u g g e s t th e p o s s i b i l i t y c r i m s o n c l o v e r m ig h t be a t t r i b u t e d for 5 n o t a f f e c t e d by 2 p e r c e n t as a t h i n rio o o n o f aoout 2 to 3 m icrons in T he c u t i c l e osm ic a c i d . su D cu ticu lar Im per­ the s u o c u tic u la r h y d r o c h l o r i c a c i d a n d 2 p e r c e n t ammonium h y d r o x i d e . acid d isso lv e s of and m e a b l e s e e d b e c o m e p e r m e a o l e when t r e a t e d w i t h t h e a c i d m in u tes. In nam ely th e m a c r o s c l e r i d s , th e th ic k - w a lle d parenchym a, and th e tissu e l a y e r s w h ic h seem t o be c h a r a c t e r i s t i c th o se l a y e r s draw n to s c a l e . seeds crim son c lo v e r same a s f o r s i m i l a r s m a l l le g u m e s were i d e n t i f i e d , the o s t e o s c l e r i d s , cle when p r e s e n t i n a 3 i d e n t i f i e d b y Ila mly ( 5 ) . Five s e p a r a te all tissu e, and V/inton ( 3 0 ) . th at as found In sweet im p erm eab ility in to an im p erv io u s cu ticle. -1 1 - The s u b c u t i c u l a r a r e a d i s s o l v e s i n a 2 Der c e n t h y d r o c h l o r i c a c i d f o l l o w e d by 2 p e r c e n t ammonium h y d r o x i d e i n d i c a t i n g the p e c t i c nature o f t h i s m a t e r ia l. t i n g e o f b l u e r e s u l t i n g from c h l o r z i n c i o d i d e h em icellu lo se t o be p r e s e n t . to extend in to of The f a i n t shows some T h i s f a i n t b l u e may be d i s c e r n e d t h e open ends o f the m a c r o s c l e r i d s to th e d ep th the l i g h t l i n e . Reeve ( 2 5 ) , and Hamly ( 5 ) h a v e c l a r i f i e d the nature of t h e m a c r o s c l e r i d s and t e s t s w ith crim son c l o v e r s u b s t a n t i a t e th eir (30) ob servation s. W in to n T r i f o l i u m as b e i n g f l a t d escrib es on t h e o u t e r e n d s . the m a c r o s c le r id s o f T h i s was f o u n d t o b e t r u e b u t i n no m a t u r e s e e d s e x a m i n e d was t h e o u t e r w a l l fo u n d t o be i n t a c t , u n le ss the su b cu ticu la r area i s as the o u ter w a l l . The d i f f e r e n c e i n c o m p o s i t i o n w o u l d make th is u n lik ely , on t h e b a s i s cells co n sid ered b u t t h e a b s e n c e o f an o u t e r w a l l may be e x p l a i n e d o f a c o m p l e t e r u p t u r e a s shown by Hamly ( 5 ) . a r e somewhat s m a l l e r t h a n t h o s e o f r e d c l o v e r , These measuring- 35 t o 4 5 m i c r o n s i n l e n g t h and 13 t o 18 m i c r o n s i n c r o s s s e c t i o n . The c e l l c o n t e n t s w e r e n o t d e t e r m i n e d b u t i t was o b s e r v e d t h a t c o n s i d e r a b l e t i m e was r e q u i r e d f o r d e c o m p o s i t i o n by s u l f u r i c a cid . R eaction to s u lf u r ic a c i d and i o d i n e show ed t h a t t h e w a l l s w er e co m p o s e d o f c e l l u l o s e . 7 to 9 The l i g h t l i n e w h i c h o c c u r r e d m i c r o n s b e l o w t h e s u r f a c e d i s a p p e a r e d when m a c e r a t e d w i t h h y d r o c h l o r i c a c i d and ammonia. Hamly ( 5 ) , and R e e v e s (25) This co n fir m s th a t the l i g h t lin e the f in d in g s is of c a u s e d by a -13- F ig. 1. C r o s s S e c t i o n View Through t h e S eed C oa t o f Crimson C l o v e r . S c a l e 1 mm. * 1 m i c r o n , a - C u t ic le , 0 - S uO cuticlar la y e r , c - l i g h t l i n e , d - M acrosclerid s, e - O ste o s c le r id s, f - N u t r i e n t l a y e r , g - A l e u r o n e , h - En dosp er m, i - c r o s s s e c t i o n o f upper p a r t o f m a c r o s c l e r i d , j - C ro ss s e c t i o n through low er p a r t o f m acrosclerid s. -1 3 - d ifferen ce illu sio n in r e f r a c tiv e in d e x b r i n g i n g about an o p t i c a l ra th e r than a s tr u c u r a l d iffe re n c e Coe a n d h a r t i n (3), and h a r t i n (17) as s t a r e d in t h e i r stu d ies oy of sweet c lo v e r. The o s t e o s c l e r i d s than those a p p e a r e d t o oe o n l y s l i g h t l y of o th er clovers e x a m i n e d a y P tm m e l ( 2 2 ) larger out agree m ore c l o s e l y w i t h h i n t o n ’ s (30) d e s c rip tio n of th e se red c lo v e r. as c l e a r l y d e f i n e d a s f i g u r e shows These c e l l s are not in numerous s eed c o a t s 1 in depth. The s t r u c t u r e ceen w ell i l l u s t r a t e d and b y a t t (17) cellu lo se-lik e o f these th eir dim ensions as l e n g t h a n d 13 t o 18 m i c r o n s cells in o th er sw e d e s has ay Pammel ( 2 2 ) , V J i n to n ( 3 0 ) , and t h e i r c o m p o s i t i o n m ateria ls and M a rtin g iv e n as p e c t i c and a y Hamly ( 5 ) . The r e m a i n i n g c e l l s of th e M easurem ents o f o c c a s i o n a l re/ealed a p p r o x i m a t e l y 20 t o 25 m i c r o n s i n part in b u t seem t o b e s o m e w h a t c o m p r e s s e d o r f u s e d w i t h t h e t h i n - w a l l e d parenchym a u n d e r n e a th . cells cells are not u su ally c o n s id e re d as a s p e r m o d e r m b u t a s 3n e n d o s p e r m t i s s u e . sperm appears to be i d e n t i c a l w ith s i m i l a r lay ers T he e n d o ­ of c e lls in sw eet c lo v e r and a l f a l f a . A m a r k e d d i f f e r e n c e was o b s e r v e d , how ever, o f t h e t h i c k - w a l l e d parenchym a w hich in th e thickness m e a s u r e d a p p r o x i m a t e l y 40 t o 50 m i c r o n s a t t o 70 t o 90 m i c r o n s a t To t e s t the sid es. the h y p o th e s is c l o v e r may b e a t t r i c u t e d th e ends of th e seed , th at im p erm eab ility in to th e c u t i c l e , crim son h alv e s of seed coats -14- w e r e c e m e n t e d t o t h e e n d s o f g l a s s t u b i n g drawn out t o a little less structure than the diam eter of a seed . of the b e f o r e m ounting, ammonia. The i n t e r n a l s e e d c o a t was t h o r o u g h l y d i s o r g a n i z e d , w ith 2 p e r c e n t h y d r o c h l o r i c a c i d and The c e m e n t u s e d was a w a t e r - p r o o f t y p e and when a p p l i e d e x t r e m e c a r e was t a k e n t o l e a v e of the seed coat exposed. t h e m ajo r p o r t i o n The t u b e s w e r e p a r t l y f i l l e d a s a t u r a t e d s u g a r s o l u t i o n and im m ersed i n w a t e r . This t e c h n i q u e was s u c c e s s f u l w i t h two o f t h o s e o r e p a r e d . 48 h o u r s t h e r e was no r i s e In o f th e w a te r l e v e l i n t h e s e two. I n t u b e s w h ere t h e c e m e n t i n g p r o c e d u r e f a i l e d t o s e a l th e ends t h e w a t e r r o s e t o t h e same h e i g h t a s t h e c a p i l l a r y r i s e th e open ended ch e c k . safe ivith On t h e b a s i s o f t h e t e s t i t of appears t o c o n c l u d e t h a t i m p e r m e a b i l i t y i n c r i m s o n c l o v e r i s d_ue in nart to the w e ll developed c u t ic le Treatm ent o f u n s c a r i f i e d t h e o b s e r v a t i o n s o f Hamly ( 5 ) la y er. se e d w it h osmic a c i d c o n fir m ed , and M a r t i n and Wyatt w ater e n t e r s perm eable seed through a ru p ture i n the b u t an i n t a c t (17) that stro oh iole, s t r o p h i o l e p r e v e n ts the a b so r p tio n of w ater. S i n c e no d i f f e r e n c e s c o u l d be f o u n d i n t h e c u t i c l e h a r d and s o f t seeds, it stro p h io le t h e d o m in a n t f a c t o r a f f e c t i n g w a t e r a b s o r p t i o n , is is an d w o u l d m a t e r i a l l y a f f e c t la y e r of e v id e n t th a t th e c o n d it io n of the any e f f o r t s b reed in g true fo r p e r m e a b ility . to is o la t e lin es • -1 5 - II. EFFECT OF INBREEDING M eth o d s and M a t e r i a l s S e e d fro m f o r t y p l a n t s , h a r v e ste d in the s e l e c t e d a t random, s p r i n g o f 1 9 4 2 and g e r m i n a t i o n d e t e r m i n e d a f t e r h u l l i n g by hand. T e s t s were ru n i n a c c o r d a n c e w i t h t h e o f f i c i a l m e th o d ( 2 6 ) w i t h a l l l i v e days being c la s s e d as hard. d ifferen ce w ere se e d not g erm in a tin g in W i th t h e e s t a b l i s h m e n t 6 of p la n t t h e r e m a i n i n g s e e d was d i s c a r d e d i n f a v o r o f i n b r e d m aterial. New m a t e r i a l was o b t a i n e d i n t h e s p r i n g o f 1 9 4 4 from three sources: volun teer p lan ts farm a t A t h e n s , G eorgia, g r o w i n g a r o u n d t h e Agronomy p l a n t s from a l o t o f seed im ported f r o m E u r o p e i n 1 9 3 8 and c o m b in e d d u r i n g t h e i n t e r v e n i n g y e a r s for seed in g purp oses, and s e e d o f a v o l u n t e e r i n g s t r a i n known as A l l e n ' s . S i x h u n d r e d random p l a n t s w er e s e l f e d by P l a c i n g s m a l l e n v e lo p e s of onion skin paper over the head s. These e n v e lo p e s w e r e made w i t h w a t e r - p r o o f c e m e n t and t h e c l o s e d c o r n e r s clip p ed s lig h t ly to provid e fo r a e r a tio n . e n v e l o p e s were f o l d e d around th e p l a n t paper c l i p . The b o t t o m o f t h e s t e m s and h e l d w i t h a E v e r y two or t h r e e d a y s t h e e n v e l o p e s w e r e r e m o v e d in order to r o l l the heads to a s s i s t in p o llin a t io n . At h a r v e s t t i m e t h e s e l f e d h e a d s w er e k e p t s e p a r a t e from t h e o p e n p o l l i ­ nated heads. -16- A v i o l e n t r a i n s t o r m c a u s e d s u c n l o d g i n g t h a t i t was d ifficu lt to lo c a te a l l the p la n ts s e lf e d C on sid erin g tne f a c t tn a t t e s t s i n t n i s m anner. in the seed germ in ation l a b o r a t o r y a t t n e C o l l e g e o f A g r i c u l t u r e showed c r i m s o n c l o v e r t o ru n 5 t o 10 p e r c e n t h a r d , i t was f e l t t h r e e hundred p l a n t s were r e c o v e r e d , enough m a t e r i a l w o u ld be a t hand t o p r o v i d e f i f t e e n w i t h impermeable s e e d . that i f to t h i r t y p la n ts for p a ren ts C o n s e q u e n t work showed t h a t t i m e w o u l d n o t p e r m i t t h e h u l l i n g and g e r m i n a t i o n o f a l a r g e r number o f p l a n t s . S e e d o f t h i s c r o p and o f t h e f o l l o w i n g c r o p w e r e h u l l e d w i t h a h u l l e r d e s i g n e d and b u i l t by t h e a u t h o r ( 1 0 ) . The d e s i g n a n d o p e r a t i o n o f t h i s m a c h in e h a s b e e n p r e v i o u s l y r e ­ p o r t e d and was f o u n d t o be an e x c e l l e n t h u llin g , b ut n o t a s r a p i d a s d e s i r e d . s u b s t i t u t e f o r hand H u llin g o f the crops o f 1 9 4 6 and 1 9 4 7 was d o n e w i t h an im pro vem en t o f t n e h u l l e r reported by H i g b e e ( 7 ) . The i m p r o v e m e n t s c o n s i s t e d o f l i n i n g t h e drum w i t h c o r r u g a t e d r u b b e r m a t t i n g and i n s t a l l i n g a b u ilt-in blower f o r rem oving t h e h u l l s . c a n v a s b e l t i n g was u s e d f o r in sta lled out by t h e Rubber i m p r e g n a t e d b e a t e r s and a r u b b e r v a l v e was b e l o w t h e h o p p e r t o p r e v e n t s e e d fro m b e i n g t h r o w n beaters. The e x t e n t o f s c a r i f i c a t i o n was f e l t to be s m a l l w i t h e i t h e r m a c h i n e . G e r m i n a t i o n t e s t s w e r e r u n a t 25 d e g r e e s C e n t i g r a d e on t h e open p o l l i n a t e d s e e d , and t h e s e l f e d seed were saved -17- fo r p la n tin g purposes. S e l f e d s e e d f rom p l a n t s p r o d u c i n g t h e l a r g e s t p e r ­ centages of s o ft, o f 1944. and o f h a r d s e e d w e r e p l a n t e d i n t n e f a l l Tne p r o g e n y o f t h e s e w e r e s e l f e d and p r o c e s s e d i n t h e same manner a s t n e o r i g i n a l p a r e n t s . parents for the 8 3 and S3 g e n e r a t i o n s , Hard and s e e d e d w i t h an o c c a s i o n a l e x c e p t i o n , w e r e c h o s e n o n l y from t h e p r o g e n y o f t h e i n i t i a l hard-seeded l i n e s . lik ew ise selected The s o f t - s e e d e d 8 3 , and p a r e n t s were fro m t h e p r o g e n y i n t h e s o f t - s e e d e d l i n e s . The s m a l l c h a n g e i n g e r m i n a t i o n d e v e l o p i n g b e t w e e n 21 and 63 days le d to th e r e d u c tio n o f the germ in ation p er io d to tne 2 1 -day p eriod . R e s u l t s and D i s c u s s i o n As shown i n T a b l e I t h e s e a s o n o f 1 9 4 2 wa.s a p p a r e n t l y f a v o r a b le f o r th e developm ent o f s o f t s e e d . The mean o f 4 . 4 p er c e n t hard seed a p o e a r s to co n firm th e o b s e r v a t i o n s o f Kephart (1 3 ) t h a t c r i m s o n c l o v e r p r o d u c e s a s m a l l amount o f impermeable s e e d s . The v a r i a t i o n from no hard s e e d t o 2 4 . 7 p e r c e n t in d ica tes tn a t crim son c lo v e r p l a n t s d i f f e r o f h a rd s e e d p r o d u c e d . This i s i n agreement w it h th e r e s u l t s o b t a i n e d by L u t e ( 1 5 ) w i t h a l f a l f a , p lan ts of lesp ed eza , i n t h e amount and t h e v a r i a t i o n b e t w e e n a s n o t e d by P e i t e r s (24). The l o w p e r c e n t a g e o f h a rd s e e d p r o d u c e d by t h e f o r t y p lan ts c o r r e s p o n d s t o amount o b t a i n e d i n g e r m i n a t i o n -18TABLE I PER GENT HARD SEED IN FORTY RANDOM PLANTS : : P l a n t No. Per cent hard seed * • : P l a n t No. 7.2 12.7 1.7 6.3 0.4 1 2 3 4 5 6 2.2 7 8.7 5.8 8 .4 8 9 21 22 23 24 25 26 27 28 29 30 31 32 33 6 .0 10 11 12 5.0 0 .7 1.4 13 34 35 36 37 38 39 40 2 .1 1 .1 14 13 16 17 18 19 2.7 2 .8 1 .1 1 .6 .0 20 : : tests of com bined s e e d . ever, should have kept s c a r i f i c a t i o n 0 0 1.6 3.4 2 .1 5.9 2.9 1 1 .8 24,7 In su fficien t seed 15.0 1.3 17.3 0 .8 1.3 3.6 2.4 T he g e n t l e m e t h o d o f h u l l i n g , t h a t p l a n t 32 y i e l d e d s e e d 2 4 . 7 p e r None o f 0 Dead s e e d .7 4 .4 he an support of t h i s Per cent hard seed a c a m ininun. cent hard is ho w­ Th e f a c t evidence in assum ption. the p la n ts used in t h i s stu d y y ie ld e d a h ig h p ercentage of hard seed. The v a r i a t i o n p r e s e n t , te d th e o o s s i o i l i t y se le c tio n th at how ever, i n a l a r g e r p o p u l a t i o n n i 0h t re v e a l p la n ts w ith a h ig h er degree of im p erm eab ility . q u e n t w ork showed t h i s t o s gges- oe p o s s i b l e . Subse­ -19- The mean g e r m i n a t i o n o f t h e t h r e e - h u n d r e d and t h r e e p lan ts selfed g rap h ically i n 1 9 4 4 i s p r e s e n t e d i n T a b l e I I and i l l u s t r a t e d i n F i g u r e S. The g e r m i n a t i o n r e c o r d o f a l l p l a n t s may toe f o u n d i n t h e A p p e n d i x . per cent rep resen ts a l l th e germ inator. ea rlier The mean g e r m i n a t i o n o f 5 7 . 8 s e e d w h i c h s o f t e n e d w i t h i n 63 d a y s i n The d e g r e e o f i m p e r m e a b i l i t y c o n f l i c t s w i t h ob servation s r e la t iv e d u c e d by c r i m s o n c l o v e r t o t h e amount o f h a r d s e e d p r o ­ (13). TABLE I I MEAN GERMINATION OF PLANTS SELFED IN 1 9 4 4 D ays i n germ inator : : Per c e n t germ ination : : Days i n germ inator 27.4 34.0 37.1 39.5 4 1 .4 2 4 6 8 1 0 1 2 14 21 63 Per c e n t germ ination 4 2.4 43.5 49.1 57.8 E x t r e m e v a r i a t i o n ma.y be n o t e d w i t h on e p l a n t y i e l d i n g o n l y per c e n t , ana o t h e r s a s h i g h a s The f a i l u r e 1 0 0 per cen t perm eable se e d . o f many p l a n t s t o s e t s e e d when s e l f e d e l i m i n a t e d many p o t e n t i a l p a r e n t s . Twenty-two p l a n t s w it h a mean p e r m e a b i l i t y o f 8 5 . 7 p e r c e n t p r o d u c e d en o u g h s e l f e d t o be u s e d a s s o f t - s e e d e d p a r e n t s . of th ese parents, 6 seed The r a n g e i n p e r m e a b i l i t y a s shown i n T a b l e I I I was f rom 71 t o 1 0 0 p e r -2 0 - 90 80 Per ce/?^ Soft S e e d 70 60 fo 40 30 D<$yS in <}<2rmin<$ton F ig. 2. G erm ination Rate of T o ta l P la n t P o o u la t io n S e lf e d in 1944. -21- c e n t b a s e d on t h e 6 3 - d a y g e r m i n a t i o n t e s t . germ in ation o f th e se p aren ts i s also The r a t e o f illu stra ted in F ig u r e 3. T a b l e IV and F i g u r e 4 p r e s e n t s t h e g e r m i n a t i o n r e c o r d o f t w e n t y - n i n e p l a n t s w h i c h s e t en ou gh s e l f e d t h e ir u se as hard-seeded p a ren ts. seed to allow I t may be o b s e r v e d t h a t t h e a v e r a g e p e r m e a b i l i t y o f t h e s e p a r e n t s was 2 5 . 4 p e r c e n t w i t h a range o f 8 t o 41 p e r c e n t . I f t h e d e g r e e o f i m p e r m e a b i l i t y w ere an i n h e r i t e d o r v a rieta l ch a ra cteristic, p a r e n t s d i f f e r i n g s o w i d e l y c o u l d be ex p ected to produce s im ila r progeny, u n l e s s t h i s q u ality is o f s u c h h e t e r o z y g o u s n a t u r e t h a t s e v e r a l y e a r s w o u ld be r e ­ q u ired to i s o l a t e pure l i n e s . The 2 1 - d a y g e r m i n a t i o n r e c o r d o f t h e f i r s t progeny i s 5 and 6 . gen eration g i v e n i n T a b l e s V and VI and i l l u s t r a t e d When t h e mean d i f f e r e n c e o f 0 . 3 t i o n o f t h e two g r o u p s i s in Figures per c e n t i n germ ina­ c o n s id e r e d , i t woulc appear t h a t th e c h a r a c t e r i s t i c s o f th e p a r e n t s were not e v id e n t i n th e progeny. In g e n e r a l t n i s 44, 49, is and 63 f e l l parents s e le c te d true, but th r e e s o f t - s e e d e d progeny l i n e s , w ith in th e range o f th e p e r m e a b ility o f the on t h e b a s i s o f t h e 63-d ay t e s t . 49 was t h e o n l y o n e s o f t e r I t may be s e e n t h a t and 2 3 4 from P r o g e n y group than the p a r e n ts . six lin e s , 14, 117, 131, 175, 198, t h e hard s e e d e d p a r e n t s f e l l w i t h i n t h e range —2 2 TABLE I I I GERMINATION OF SOFT-SEEDED S-. PLANTS SELECTED AS PARENTS P lan t ; ___ number : • 6 : 8 10 25 70 69 83 70 84 97 44. 8 58 . 4 6 4 ,_0 6 6 ,5 69.6 46 91 24 159 19 0 205 213 249 266 2 79 285 289 300 : 42 23 51 78 52 44 72 76 70 84 84 SO 97 7 1 1 0 4 64 70 94 53 54 64 62 46 78 45 28 53 79 52 47 73 76 70 84 84 90 97 11 20 : 44 62 94 37 36 62 54 32 47 35 14 51 69 50 37 62 75 70 84 84 90 97 1 35 44 49 57 61 63 72 84- Mean 2 G e r m i n a t i o n by d a y s 20 50 42 23 25 20 9 41 32 35 20 64 67 94 47 45 64 59 41 66 : : 14 72 75 97 76 79 69 72 75 94 61 54 64 92 64 55 87 78 71 84 85 90 97 7 6 .8 68 68 72 94 57 70 72 94 59 72 66 66 62 52 65 59 92 54 36 59 84 59 50 81 77 70 84 84 90 97 69 73 94 59 74 67 65 61 92 54 40 59 84 59 50 84 77 71 84 84 90 97 71.4 72.1 8 8 51 35 57 82. 59 47 75 77 70 84 84 90 97 : 1 2 21 : 63 82 80 1 0 0 90 8 8 77 84 89 95 84 77 94 1 0 0 78 71 90 79 72 84 8 6 90 97 85.7 -23- 9o /-^er cdnt soft s<£ D a y 5 in F ig. 5. /O fZ 14- c j< z rm r n d t o r R ate of G erm ination of Progeny of S o f t seeded S i Parents -51- TABLE VI GERMINATION OF PROGENY OF HARD-SEED S i PARENTS P lan t number 5-1 •* • «• : 2 ♦• : 4 • ; Germ ination by d a y s •• • • f» 8 : 10 6 : : 12 S *• 14 ; 21 Mean 34 29 47 69 47 32 35 55 43.5 47 31 49 73 49 39 38 69 49 .3 47 32 49 73 49 40 40 74 50.5 47 32 49 74 49 40 41 76 51.0 47 32 49 74 50 42 41 76 51.3 47 32 49 74 50 44 41 79 52.0 47 32. 49 74 51 44 41 79 52.1 47 37 49 75 62 50 46 82 56 14-1 1 2 2 20 13 27 16 28 16 28 18 30 24 24.0 18 32 25 25.0 79 24 62 2 3 4 5 6 7 8 3 Mean 17 16.3 21 21 2 2 16 29 23 20.3 2 1 .6 2 2 .0 2 2 .6 16 29 24 23.0 63 79 16 38 71 57 46 51.1 79 16 40 73 57 46 51.8 79 18 49 81 57 49 55.5 79 19 49 81 57 50 55.8 79 29 31 25 34 23 55 33.6 34 29 36 24 57 36.0 40 34 40 30 65 41.8 68 68 60 37 55.0 67 37 57. 3 75 77 40 64.0 47 70 54 47 72 54 50 76 55 Mean 2 1 .6 79 16 26 69 57 45 48.6 92-1 10 24 27 15 26 15 48 21 21 2 2 31 32 22 22 2 2 .8 30 19 49 28.6 51 30.4 52. 31.4 31 23 34 23 52 32.6 54 40 26 40.0 65 50 35 50.0 65 50 36 50.3 65 51 36 50 .4 65 58 37 53.3 43 56 46 46 64 48 47 65 50 47 47 6 8 68 53 54 6 6 -1 2 11 3 4 5 5 14 26 6 11 2 3 4 5 Mean 93-1 2 3 Mean 94-1 2 3 20 51 81 57 50 56.3 8 6 58 50 59.8 -32- TABLE VI ( C o n t l d . ) ♦ • P lan t number • « : 94-4 5 6 7 Mean 97-1 2 3 4 Mean 99-1 G-erminatlon b y d a y s • • « 2 : 4 : 6 : » • • « 9 8 : : 1 0 1 2 • * • « : 14 : 33 53.7 56 54 92 33 5 6 .7 57 57 92 33 58.1 57 65 92 33 5 9.4 58 61 92 36 60.5 58 73 92 36 61.7 61 78 92 39 64.4 52 49 31 24 39.0 54 57 52 36 4 9 .7 62 63 59 54 59.5 64 64 60 58 61.5 72 67 61 63 65.7 72 71 63 64 67.5 80 74 67 67 72.0 86 36 18 4 23 9 26 41 48 49 22 22 22 51 24 53 25 56 28 18 27 47 57 18 27 47 65 18 27 47 70 20 20 22 29 47 79 33 39.5 31 47 82 33 41.5 32 51 87 38 44 .8 72 67 54 61 63.5 56 41 56 23 87 33 49.1 8 8 2 2 2 2 22 22 1 9.7 23.4 35. 5 36.4 49 24 19 29 47 73 33 3 9.1 57 42 31 34 41.0 64 52 45 49 52.5 71 56 48 52 5 6 .7 72 57 48 52 57.2 72 57 49 54 5 8.0 72 59 51 54 59.0 72 60 52 57 60. 54 49 44 53 52 5 0.4 54 56 48 58 53 5 3.8 56 58 48 65 53 5 6.0 56 58 48 65 54 56. 2 56 59 48 65 55 56. 6 56 59 50 65 56 57.2 56 60 50 65 57 57. 117-1 2 2 2 1 2 38 14 3 4 5 17 15 16 1 6 .4 31 14 19 19 21 25 24.0 38 14 28 25 27 26.4 39 14 34 31 27 29.0 52 14 34 31 29 32.0 62 15 36 32 50 35.0 2 3 4 5 6 7 Mean 1 0 0 -1 2 3 4 Mean 106-1 2 3 4 5 Mean Mean 21 2 0 .-8 2 2 21 2 81 70 73 77.5 63 62 52 66 6 64 61.4 65 20 42 36 38 40.2 ^33- TABLE VI ( C o n t ' d . ) Plan t number G e r m i n a t i o n by d a y s • • « • : 2 : 4 : 6 : 8 • • • • • « : 10 : 12 ; T 4 ; 21 119-1 2 3 Mean 25 30 24 2 6.3 26 58 26 37.0 26 60 28 38.0 26 60 28 38.0 27 64 28 3 9 .6 28 66 28 4 0 .6 28 68 31 4 2 .3 32 69 35 45.3 131-1 2 3 Mean 40 20 28 2 9.3 41 20 28 2 9.6 41 23 29 31.0 41 23 29 31.0 42. 23 29 3 1.3 42 23 29 31.3 42 24 30 32.0 42 28 30 33.3 137-1 2 Mean 27 46 36.5 39 56 47.5 44 58 51.0 46 62 54.0 46 62 5 4.0 50 62 56.0 53 62 57.5 61 64 62.5 146-1 2 3 4 5 6 Mean 2 57 27 21 19 27 2 5.5 12 60 54 41 45 47 43.1 20 61 57 45 49 57 48.1 21 61 57 45 49 57 48.3 24 61 59 47 52 58 50.1 37 63 60 48 55 59 53.6 44 63 60 49 60 62 5 6 .3 49 70 62 59 71 65 62.7 148-1 152-1 167-1 172-1 83 1 51 12 87 9 66 40 87 28 69 49 87 33 69 52 88 45 69 53 88 51 69 56 90 51 69 68 94 56 69 81 9 11 2 7 .3 9 11 2 7 .3 9 11 2 7.3 10 11 2 7 .6 10 11 2 7.6 10 11 2 7 .6 10 11 2 7.6 175-1 2 3 Mean 2 5 2 3 .0 24 80 84 84 86 86 87 89 181-1 2 Mean 16 21 1 8.5 54 66 60.0 58 73 65.5 61 74 67.5 61 76 6 8 .5 65 78 71.5 69 78 7 3 .5 72 82 77.0 183-1 2 3 Mean 19 64 11 31.3 21 66 20 3 5.6 24 67 23 38.0 24 69 23 38.6 24 69 27 24 71 30 41.6 24 73 32 43 .0 24 78 34 45.3 ! Ol . o 179-1 -34TABLE VI (G on t'd .) P lan t number : 2 : 4 : G e r m i n a t i o n by d a y s 6 : 8 : 10 : 12 196-1 198-2 39 3 78 23 81 26 215-1 2 3 4 5 6 7 9 Mean 7 83 31 23 27 69 22 40 37.7 12 86 34 35 29 69 31 40 42.0 219-1 2 3 Mean 7 20 18 15.0 2 2 1 -1 2 3 4 5 Mean 23441 2 3 Mean G-eneral Mean 81 26 : 14 : 21 82 29 85 35 86 35 92 39 12 87 35 37 32 69 39 40 43.8 13 14 87 87 36 36 37 40 35 35 81 81 43 43 40 40 46.5 46.8 14 87 36 41 35 81 47 40 47.6 14 87 36 41 35 81 53 44 4 8 .8 15 88 36 42 39 81 65 48 51.7 12 69 24 35.0 16 73 24 37.6 19 18 77 77 24 24 39.6 4 0 .0 20 79 24 41.0 26 84 24 44.6 33 91 26 50.0 9 20 46 56 7 27.6 11 34 72 64 23 40.8 11 34 73 64 23 41.0 11 11 34 34 73 73 64 64 23 23 41.0 4 1 .0 11 34 74 64 27 42.0 11 35 74 64 31 43 .0 11 36 77 67 34 45.0 13 6 18 12.3 3 0 .4 21 14 42 25.6 40.9 21 14 45 26,6 44.1 26 28 14 14 47 45 28.3 29.6 45.1 46. 6 31 14 50 31.6 47.9 33 14 50 3 2 .3 4 9 .4 33 14 51 34.3 53.2 -35- 90 f° 6 87 83.8 : « • 8 89 84.8 95 95 1 0 0 1 0 0 96 90 95.2 96 91 9 5.5 50 50 85 64 55 50 90 68 70 50 50 80 64 62 61.2 63.4 13 84 10 0 40 68 6 6 .6 10 39 86.4 : 1 2 89 86.7 : • • 14 89 86 .7 : 21 89 8 8 .2 98 98 1^ 0 1 0 0 96 91 96.2 96 94 97.0 96 94 9 7.0 98 96 98.0 50 50 95 70 70 69.0 65 50 65 50 65 57 98 1 0 0 98 1 00 1 00 1 0 0 10 0 70 74 71.8 70 74 71.8 72 76 74.0 43 43 43 49 62 1 0 0 10 0 1 0 0 1 0 0 10 0 68 73 73 94 64.7 1 00 1 0 0 1 0 0 10 0 1 0 0 10 0 78.2 79.0 79.5 80.7 82.2 86.7 92 92 94 72 90 95 98 10 0 1 0 0 8 8 .0 97 96 97 97.0 97 96 97 9 7.6 46 25 3 40 28.5 85 70 33 79 6 6.7 90 70 60 91 77.7 94 80 70 95 8 4 .7 49-2-5-1 49-2-5-2 49-2-5-3 49-2-5-4 49-2-5-5 Mean 58 45 80 48 85 63.2 96 85 84 95 8 9 .6 98 90 96 96 95 96 .6 49- 2- 7-1 4 0 80 100 66 : • • • 8 8 75 98 1 0 0 97 10 0 97 98.4 98 100 90 99 96 .7 80 80 85 98 98 98 1 0 0 1 0 0 10 0 97 1 0 0 97 98.4 98 1 0 0 97 97 1 0 0 97 98.4 98 1 0 0 97 97 10 0 9? 98.4 1 0 0 1 0 0 97 100 1 0 0 1 0 0 98.7 98.7 99.2 1 0 0 1 0 0 10 0 1 0 0 100 1 0 0 100 1 0 0 10 0 1 00 1 0 0 1 0 0 100 10 0 10 0 1 0 0 1 0 0 10 0 95 9 9 .0 95 99 .0 10 0 100.0 100.0 100.0 100 100 100 100 10 0 10 0 1 0 0 100 1 0 0 -60- TABLE X I I I (C ont'd) G e r m i n a t i o n by d a y s Plant number 49-2-7-2 49-2-7-3 49-2-7-4 49-2-7-5 Mean 49-2-8-1 49-2-8-2 49-2-8-3 49-2-8-4 49-2-8-5 49-2-8-6 49-2-8-7 Mean 84-1-4-1 84-1-4-2 84-1-4-3 84-1-4-4 £4 - 1 - 4 - 5 84-1-4-6 Mean 84-1-5-1 84-1-5-2 84-1-5-3 84-1-5-4 Mean • • : 2 53 40 76 50 51.8 56 98 85 8 8 54 85 70 76.5 3 7 2 0 14 • • : 4 8 6 76 92 82 83.2 6 : 8 : • t 10 : • 12 : 14 97 : 21 93 84 97 97 97 1 0 0 1 0 0 1 0 0 1 0 0 100 1 0 0 10 0 1 0 0 1 00 97 1 00 100 92.6 96 98.6 96 98.6 96 98.6 98 99.0 74 98 93 94 60 90 70 82.7 75 98 93 94 62 90 70 83.1 77 98 95 94 62 90 70 8 3 .7 77 98 95 94 62 90 70 83 .7 77 98 95 94 62 90 70 83.7 77 99 95 96 62 90 70 84.1 80 99 95 96 72 95 70 86.7 6 9 23 44 34 61 44 35.8 19 30 48 37 73 48 42.5 19 32 48 37 73 52 43.5 19 37 48 40 75 72 48.5 19 37 48 43 75 72 49.0 19 42 48 46 84 53.0 20 20 15 40 31 11 4 20 8 .0 20.5 10 15 84 42 38 44.7 266-1-1-1 55 266-1-1-2 5 0 266-1-1-3 0 266-1-1-4 0 266-1-1-5 266-1-1-6 5 1 0 .8 Mean GENERAL 40.3 Mean : • f 94 98.2 0 60 35 30 33.7 • 80 1 0 4 30 1 0 40 29 .0 71.9 86 15 20 20 20 79 44 38 46.2 92 44 39 4 8 .7 92 44 42 49.5 92. 46 44 50. 5 92 48 46 51.5 96 58 62 59.0 80 15 80 25 80 55 8 1 2 20 70 45 75 51.1 85 45 85 61.6 85 55 29 95 45 90 6 . 5 95 65 40 30 55 38.0 85 55 25 95 45 85 65.C 8 8 76.6 80.4 81.5 82 .e 6 83 .1 88 1 0 0 80 1 0 0 8 8 .0 86.3 -61- 9 o 80 Per cent soft seed lo 40 30 20 10 Days in cjerm 'm ator F ig. 1 3 . G e r m i n a t i o n R.»te o f t h e P r o g e n y o f S o f t seeded S, P arents O -62- TABLE XIV GERMINATION OF PROGENY OF HARD-SEEDED S-* PARENTS G e r m i n a t i o n bv d a v s P lan t number 117-1-1-1 117-1-1-2 117-1-1-3 117-1-1-4 117-1-1-5 Mean : 2 : 4 : 6 1 2 1 2 12 6 18 14 16 18 14 17 9 8 : 8 15 18 16 17 : 10 22 6 20 20 20 20 16.0 16.2 17.2 19.0 119-3-1-1 119-3-1-2 119-3-1-3 Mean 85 60 27 5 7 .3 93 85 83 87.0 96 90 90 92.0 175-2-2-1 175-2-2-2 175-2-2-3 175-2-2-4 175-2-2-5 Mean 6 8 60 50 52 48 5 5 .6 72 60 70 60 60 64.4 72 67 78 60 69.0 1 2 20 8 .2 68 : 15 18 2 15 18 25 24 28 2 .C : 14 20 20 28 32 40 28.0 : 21 25 38 38 41 48 38.0 96 96 97 97 99 1 00 1 00 1 0 0 1 0 0 1 0 0 97 97.6 1 00 1 0 0 1 0 0 1 0 0 9 8 .6 9 9.0 99.0 99.6 72 77 78 60 72 71.8 76 80 80 60 73 73.8 84 80 83 60 75 76.4 84 80 96 90 89 72 81 85.6 85 95 74 84 77 87 95 76 84 80 84.4 80 85.2 8 6 60 76 77.2, 87 95 76 92 95 80 96 84 67 76.0 78 95 70 84 70 79.4 8 3 .0 85 95 76 84 80 84.0 63 44 80 62.3 76 44 87 69.0 76 46 87 69.0 80 50 90 73.3 83 50 90 74.3 83 50 90 74.3 83 50 90 74.3 58 94 79.3 175-2-5-1 175-2-5-2 175-2-5-3 175-2-5-4 175-2-5-5 Mean 30 52 50 50 55 47 .4 30 60 50 90 60 52.0 30 30 70 55 65 70 58.0 30 70 60 65 80 61.0 30 70 60 65 85 62.0 30 70 60 65 85 62.0 40 74 60 70 95 67.8 175-2-6-1 175-2-6-2 80 25 84 47 87 50 87 51 89 51 93 58 175-2-3-1 175-2-3-2 175-2-3-3 175-2-3-4 175-2-3-5 Mean 85 62 84 60 71.8 175-2-4-1 175-2-4-2 175-2-4-3 Mean 6 8 73 90 6 6 68 55 60 65 55.6 8 6 86 49 50 8 8 86 89.8 86 -63- TABLE XIV ( C o n t ' d ) Ger m i n a t i o n by d a y s • • » P lan t number 175-2-6-3 175-2-6-4 175-2-6-5 175-2-6-6 Mean 57 95 65 23 5 7.5 4 67 95 85 89 77.8 175-2-7-1 175-2-7-2 175-2-7-3 175-2-7-4 175-2-7-5 175-2-7-6 Mean 90 76 95 90 80 87 86.3 90 76 95 95 92 87 89.1 183-1-1-1 183-1-1-2 183-1-1-3 183-1-1-4 Mean 183-3-1-1 183-3-1-2 183-3-1-3 183-3-1-4 183-3-1-5 183-3-1-6 183-3-1-7 183-3-1-8 Mean 2 : : 6 4 4 • • : 8 80 95 90 93 82.1 83 95 90 93 82.8 •95 80 95 1 0 0 1 0 0 93 93 92.6 80 95 1 0 0 93 93 93.5 : • • 10 83 95 90 97 83.6 1 0 0 84 95 : 12 : 21 8 8 .6 1 0 0 1 00 1 0 0 84 95 84 95 84 95 8 6 1 0 0 1 0 0 95 93 94.5 95 93 94.5 97 93 94.8 1 0 0 94 95 95 97 100 97 93 94.8 1 0 0 10 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 00 1 0 0 1 0 0 1 0 0 10 0 1 0 0 1 0 0 100 1 0 0 96 95 97.7 1 0 0 10 0 100 1 0 0 10 0 1 00 10 0 98 99.5 1 0 0 10 0 1 0 0 1 0 0 100 10 0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 1 0 0 10 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 94 80 93 98 94 82 97 98 94 84 97 98 1 0 0 1 0 0 1 0 0 100 1 0 0 85 92 89.5 95 92 93.6 95 92 94.0 95 92 94.7 95 94 95.2 219-3-1-1 219-3-1-2 219-3-1-3 219-3-1-4 219-3-1-5 Mean 90 43 85 48 60 95 46 90 49 64 95 46 92 49 -12 2 1 - 1 - 55 40 1 -2 14 95 90 97 84.6 94 77 93 98 1 -1 : 83 95 90 97 83.8 96 84 97 98 2 2 1 4 4 4 4 92 75 83 89 1 0 0 6 8 .8 55 60 66 69.6 55 60 95 46 92 50 67 66 _ 6 9 . 8 _„70._0_ 95 46 92 50 55 60 60 60 96 84 97 98 10 0 98 90 97 1 0 0 1 0 0 95 94 95.5 95 96 95.7 95 96 97.0 95 46 92 50 67 70.0 95 49 92 52 71.2 95 49 96 54 72 73.2 60 60 60 60 70 60 68 -64- TABLE XIV ( C o n t ’ d) P lan t h umber 221-1-1-3 221-1-1-4 Mean G e r m i n a t i o n bv da v s • • 2 48 46 47.2 266-1-2-1 95 266-1-2-2 97 85 266-1-2-3 78 266-1-2-4 8 6 266-1-2-5 79 266-1-2-6 266-1-2-7 76 266-1-2-8 95 97 266-1-2-9 1 0 0 266-1-2-10 1 0 0 266-1-2-11 8 9 .8 Mean General 6 7.8 Mean • 4 49 48 53.0 1 0 0 97 95 84 90 84 80 • 6 8 : 10 : 12 : 14 63 58 6 0.2 : 21 54 56 56.2 56 56 56.7 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 97 90 94 8 8 97 90 94 89 59 58 59.2 97 94 94 89 60 58 59.5 94 96 89 84 8 8 8 8 8 8 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 98 98 98 98 98 96 98 91 92 68 64 65 o 5 98 98 96 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 100 1 0 0 1 0 0 9 3.4 95.5 96.0 96.3 96.8 9 7.9 99.2 74.9 7?.3 7 8.6 7 9.6 80.3 8 1.2 84.7 -65- t seed 90 P&r c i n c h e s in to i n d i a m e t e r l e d from t h e t o o o f t h e t o w e r s th e to p c e n t e r o f th e chambers. made by d i r e c t i n g osychrom eter. the a ir H u m i d i t y r e a d i n g s were s t r e a m from e a c h t o w e r o n t o a s l i n g D e t e r m i n a t i o r s o v e r a t e m p e r a t u r e r a n g e o f 56 t o 8 6 d e g r e e s F a r e n h e i t show ed an a v e r a g e d i f f e r e n c e hum idity of 3 5 .7 per cen t. in r e la t iv e The amount o f c o n d e n s a t i o n i n s i d e the e n v e lo p e s c o n t a in in g the soonges le a d s to the p o s s i b i l i t y t h a t t h e d i f f e r e n t i a l was e v e n g r e a t e r t h a n t h a t o b t a i n e d a b o v e . R e s u l t s and D i s c u s s i o n The r e s u l t s fro m e i g h t e e n p l a n t s \vere a l m o s t a s i n ­ c o n s i s t e n t as th o s e ob ta in ed in the p r e v io u s experim ent. Table XIX sh o w s t h a t t h e r e was o n l y a mean d i f f e r e n c e o f 2 . 8 3 o e r c e n t p e r m e a b i l i t y b e t w e e n t h e two t r e a t m e n t s . A l t h o u g h no s i g n i f i ­ c a n t d i f f e r e n c e s w er e f o u n d i n g e r m i n a t i o n , it may be n o t e d t h a t in t w o - t h ir d s of the r e p l i c a t i o n s h igh hum idity produced s o f t e r s e e d than low h u m i d i t y . the d i f f e r e n c e s of 8 . 6 per c e n t , F u r th e r a n a l y s i s however r e v e a l s t h a t i n t r e a t m e n t s o f t h e s e t w e l v e p l a n t s h a v e a mean w h ic h may b e c o n s i d e r e d i d e n t i c a l w i t h t h e mean d if f e r e n c e ,8 .7 per cent, of the p la n ts w ith o p p o site e f f e c t . Though l a c k i n g s t a t i s t i c a l sig n ifica n ce a r e o f some p r a c t i c a l v a l u e . the d i f f e r e n c e s On t h e b a s i s ob tain ed of th ese r e s u l t s , the o d d s a r e two t o on e t h a t h e a d s s u r r o u n d e d by a humid a t m o s p h e r e w i l l b r i n g a b o u t an i n c r e a s e those in p e r m e a b ility of 8 per cent over s u b j e c t t o a dry atm o sp h ere. -7 9 - TABLE XIX EFFECTS OF HUMIDITY ON SEED SIZE AND GERMINATION P lan t number M i l l i g r a m s p e r 100 s e e d Humid Dry H - D 1 o 3 4 5 6 7 3 9 10 11 12 13 14 15 16 17 18 Mean 2 80 370 312 350 245 340 292 330 370 253 267 274 342 380 370 400 316 320 322.8 2 92 353 226 270 240 333 250 307 375 260 280 255 280 3 60 329 355 317 257 296.6 P e r c e n t nermea. b i l i t y Humid Dry H - D -12 17 86 80 5 7 42 23 - 5 - 7 -13 19 62 20 41 45 - 1 63 26. 2± 8 .6 The e x t r e m e d i f f e r e n c e s , 80 98 66 35 93 92 70 89 90 86 82 70 90 84 96 95 88 80 85.2 93 99 92 92 85 100 77 97 97 73 83 68 100 38 90 92 67 92 88.0 13 2 26 7 - 8 8 7 8 7 -13 1 - 2 10 4 - 6 - 3 -21 12 2 . 8 3 t 7.9 26 and - 2 1 o e r c e n t a r e o f some i n t e r e s t when c o n s i d e r e d i n t e r m s o f t h e i n b r e e d i n g s t u d y r e ­ p o rted above. T h e s e a l m o s t c on form t o t h e d i f f e r e n c e s e s t a b l i s h ­ e d f o r d i v i d i n g - p a r e n t s i n t o o e r m e a b l e and i m o e r m e a b l e c l a s s e s . The d i f f e r e n c e sig n ifica n t seed i s b u t n o t as l a r g e a s t h e d i f f e r e n c e s b r o u g h t a b o u t by v a r y i n g m o i s t u r e d ifferen ces o f 2 6 . 2 ± 8 .6 in th e w eight o f supoly. I t may be s e e n t h a t t h e l a r g e s t are in fa v o r the seed r e s u lt i n g A few e x e c u t i o n s from h i g h h u m i d i t y . are e v id e n t but in g e n e r a l h igh o e r m e a b ilit y is a s s o c ia t e d w ith large seed. The e x t e n t o f t h i s is i n d i c a t e d by a. c o r r e l a t i o n c o e f f i c i e n t a sso cia tio n oi 0 . 5 0 ! t 0 . 1 5 . -80- The v a r i a b l e r e s p o n s e i n e i g h t e e n r e p l i c a t i o n s in d ica tiv e of the d i f f i c u l t y is t h a t would o ccu r even though s e l e c t i o n f o r i m p e r m e a b i l i t y w e r e made un der c o n t r o l l e d c o n d i ­ t i o n s w i t h t h e e x p e c t a t i o n t h a t a l l p l a n t s w ou ld r e a c t i n t h e same m a n n e r. - 81 - LIGHT INTENSITY M a t e r i a l s and Methods M atu re s e e d w e r e h a r v e s t e d i n t h r e e r e p l i c a t i o n s fro m a p o r t i o n o f a f i e l d cloudy c o n d itio n s shaded w ith m u slin t o s im u la te and from t h e same f i e l d in f u l l s u n lig h t. The m u s l i n was f o u n d t o r e d u c e t h e l i g h t i n t e n s i t y by 8 , 0 0 0 fo o t can d les. The s e e d w e r e h u l l e d w i t h t h e r o t a r y h u l l e r p r e v i o u s l y d e s c r i b e d and g r a d e d i n t o t h r e e s i z e s w i t h 1 . 9 and 1 . 6 m i l l i m e t e r s i e v e s . 21 d a y s and a l l seeds G e r m i n a t i o n t e s t s were run f o r s o f t e n i n g were c o n s i d e r e d a s g e r m i n a t ­ in g or p erm eab le. R esu lts The r e s u l t s It is of t h is and D i s c u s s i o n e x p e r i m e n t a r e g i v e n i n T a b l e XX. e v i d e n t f r o m an e x a m i n a t i o n o f t h e d a t a p r e s e n t e d t h a t t h e t r e a t m e n t s h a d no m a t e r i a l e f f e c t on e i t h e r s e e d s i z e or p erm ea b ility . L igh t i n t e n s i t y ranges have not been determ ined f o r crim son c l o v e r , variou s p la n ts b u t i t h a s b e e n shown ( 1 8 , 19) that for t h e optimum l i g h t i n t e n s i t y r a n g e s fro m 2 , 0 0 0 to 5,000 fo o t ca n d les. The r e d u c t i o n i n l i g h t i n t h i s exp eri­ ment e x p o s e d t h e p l a n t s t o 20 p e r c e n t o f f u l l s u n l i g h t w h ic h is w ith in range g iv e n above. of th is experim ent th a t p a r t ly It is a p p a r e n t from t h e r e s u l t s c l o u d y w e a t h e r and o v e r c a s t -82- s k ie s i n the s p r i n g h a v e no e f f e c t of the crim son c l o v e r on t h e o e r m e a b i l i t y seed crop. TABLE XX EFFECT OF LIGHT INTENSITY ON SEED SIZE AND PERMEABILITY ♦ * Treatm ent Shade L ight : • • Re n. : Seed s i z e in p e r c e n t : Lari?e : Medium : S m a l l : Percent G erm ination 1 2 3 Means 5.6 4 .4 6.6 5.6 41.7 49.3 40.9 43.7 52.7 46.3 52.5 50.7 86 84 86 85.3 1 2 3 Means 9 .4 10.0 6.7 8 .4 33.6 38.9 45.5 40.2 57.0 51.1 47.8 51.3 91 82 74 82.3 T -83FLOWERING SEQUENCE M a t e r i a l s and Methods R eference to L u te ’ s (15) o b s e r v a t i o n on t h e d i f f e r e n c e i n p e r m e a b i l i t y o f s e e d from d i f f e r e n t b r a n c h e s o f an a l f a l f a p l a n t h a s a l r e a d y b e e n made. To t e s t d o m in a n c e i n r e l a t i o n ment was c o n d u c t e d . the p o s s i b i l i t y of flow er to p e r m e a b ilit y , the f o llo w in g e x p e r i­ S e v e n t y - f i v e w e l l branched c l o v e r p la n t s w e r e l o c a t e d i n t h e s p r i n g o f 1 9 4 6 , and 1 9 4 7 . The p l a n t s were v isited bud. d a i l y a.nd t h e h e a d s numbered a s t h e y emerged f^ora t h e F i f t e e n heads per p lan t were numbered i n 1 9 4 6 . The o p p o r t u n i t y o f f e r e d by t h e p r o f u s e b r a n c h i n g o f t h e p l a n t s u s e d i n 1 9 4 7 p e r m i t t e d t h e nu m b er in g o f t w e n t y h e a d s P e r p lan t. In a l l c a s e s th e a p i c a l heads appeared f i r s t f o l l o w e d by t h e l a t e r a l s . and were S e e d were h a r v e s t e d ivhen f u l l y m a t u r e and i d e n t i c a l h e a d numbers b u l k e d . G r a d i n g and germ ination t e s t s were c o n d u c t e d as i n t h e o r e c e e d i n g e x p e r i ­ m ent. R e s u l t s and D i s c u s s i o n The r e s u l t s XXI, o b t a i n e d i n 1946 a r e p r e s e n t e d i n T a b l e and some s t r i k i n g c o m p a r i s o n s a r e e v i d e n t . I t may be n o t e d t h a t t h e amount o f s m a l l s e e d i n c r e a s e d w i t h h e a d seouence. The c o r r e l a t i o n coefficien t was f o u n d t o b e + 0 . 8 2 ± 0 . 1 5 . w ith the sequence co efficien t of Im perm eability a ls o in c r e a s e d o f f l o w e r i n g a s i n d i c a t e d by t h e c o r r e l a t i o n -0 .6 8 iC .2 0 . betw een seed s i z e of t h is r e la t io n s h ip ' h e r e a s no s i g n i f i c a n t c o r r e l a t i o n and p e r m e a b i l i t y c o u l d be e s t a b l i s h e d f o i -1 -8 4 - TABLE XXI EFFECT OF H^AD SEQUENCE uN SEED SIZE AND PERMEABILITY OF SEVENTY-FIVE PLANTS IN 1S46 Head : number : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Seed. s i z e in p ercen t Large 5 Medium : 27 .0 40.0 24.0 4 0.7 1 9.9 43.6 1 5.5 36.9 20.1 28.4 22 .3 31.1 3 2 .7 17.2 2 4.1 33. 5 18.7 2 3.9 18.3 26.3 2 .0 .2 30.5 34.8 18 .5 1 4.0 18.5 13.4 4.1 7.0 17.6 t h e m o i s t u r e and h u m i d i t y s t u d i e s a r e su lte d in th is » • Sm all 33.0 35.3 36.5 47.6 51.5 46.6 50.1 42.457 . 4 55.4 49.3 4 6.7 67. 5 8 2 .5 7 5.4 : Percent germ ination 83.2 79.0 76.2 77.2 78.0 68.7 71.0 68.0 70.0 70.0 64.7 60.0 59.5 62.0 62.0 : : close relation sh ip e x p e r i m e n t . The c o r r e l a t i o n c o e f f i c i e n t b e t w e e n t h e p e r c e n t a g e o f s m a l l s e e d and p e r m e a b i l i t y was f o u n d t o be - 0 . 7 2 * 0 . 1 9 . I t may b e o b s e r v e d t h a t r a n g e o f p e r m e a b i l i t y p r o d u c e d a d ifferen ce h igh ly sig n ifica n t c o efficien t be of 2 3 .7 per c e n t. The d i f f e r e n c e s a l s o h a v e a lin ear rela tio n sh ip . o f i m p e r m e a b i l i t y on h e a d s e q u e n c e was f o u n d t o + 1 . 5 7 5 * 0 . 4 6 an d t h e r e l a t i o n s h i p i s F ig u re 17. The r e g r e s s i o n shown g r a p h i c a l l y i n -35- 40 30 f^er c e n t tm perm LfU2>J C>J $& 2>ubz>Q * Hanses ^r Temperature VO 18. 03 lig . o for 1946, and 1947 Crimson C l o v e r <\i E ainfall 1946 - //PjU/py SVlfDUf D istrib u tio n for 1945, and 1947 Crimson C l o v e r During oeed D evelop men t of -89- Oj •H to -9 0 were n o t fo r the rad ically d iffe re n t, The m ean maximum t e m p e r a t u r e s p e r i o d r e p r e s e n t e d d i f f e r e d b y o n l y one d e g r e e . The l o n g e s t p e r i o d o f a n y p r o n o u n c e d d i f f e r e n c e s was o f o n l y 5 days d u ratio n , f r o m flay 15 t o The s e a s o n i n than t h a t stu d y above, have d e v e lo p e d . perio d s, 194 7 a c t u a l l y h a d 1 . 1 5 i n c h e s o f 1946. Then t h i s the m o is tu re 19. There i s is c o n s i d e r e d on t h e s e e d somewhat l e s s a p o ssib ility rain b asis of perm eable should t h a t t h e two d r o u g h t A p r i l 17 t o 2 9 , a n d flay 2 t o 20 may h a v e h i n d e r e d th e developm ent of im p e rm e a b ility . w riter less (11) , h o w ev er, in v estig atio n s oy t h e show t h a t t h e d u r a t i o n o f t h i s d r o u g h t w ould n o t d e v e lo p a m o i s t u r e p roblem i n th e s o i l where th e p l a n t s were g ro w in g . A tte n tio n has of th e 194 7 p l a n t s , oeen c a l l e d to t h e p ro fu s e w h ic h a v e r a g e d c o n s i d e r a b l y auove the tw enty h ea d s p e r p l a n t . extrem ely su b ject th in to C onsidering probable in T h e s e p l a n t s w h i c h w e r e i n an s t a n d a t t a i n e d u n u s u a l s t a t u r e a n d were little o r no c o m p e t i t i o n the e n v iro n m e n t th at orancliing oy s u r r o u n d i n g v e g e t a t i o n . and th e ty p e o f p l a n t i t is th e e a r l i e r h e a d s were f a r enough advanced t h e i r d e v e l o p m e n t so t h a t d o m i n a n c e oi not a fa c to r h in d erin g e a r l y h e a d s was th e developm ent of l a t e r heads. -91- NUTRIENT LEVELS M e t h o d s and M a t e r i a l s I t has b een f o u n d by t h e w r i t e r t h a t when s e e d o f i d e n t i c a l o r i g i n was o l a n t e d a t E x p e r i m e n t , m iles f a r t h e r so u th , and a t T i f t o n , con d ition s, make i t i t m ig h t be S in ce t h i s experim ent has t h a t l e s s p r e c i p i t a t i o n a t T i f t o n was t h e f a c t o r b r in g in g about the d i f f e r e n c e . To c h e c k t h e i n f l u e n c e o f n u t r i e n t l e v e l s , h a l f - p l a n t s as d e s c r i b e d a b o v e w er e s u b j e c t e d t o two d i f f e r e n t l e v e l s phosphorus, and p o t a s s i u m . and t h r e e - f o u r t h s s a n d was p r e p a r ­ To e s t a b l i s h d i f f e r e n t f e r t i l i t y added a t 500 t o 1 0 0 0 of calcium , A s o i l m ixture c o n s i s t i n g o f one- f o u r t h c l a y lo a m w i t h p e a t m oss , ed. (6 ) a study of th e weather reco rd s at both s t a t i o n s seem l i k e l y most e f f e c t i v e A lthough H arrin gton the s u s p ic io n arose that a fa c to r in flu e n c in g p erm eab ility. b een c o n c l u d e d , 150 tha.t t h e s e e d c r o p s a t T i f t o n w er e l e s s p e r m e a b l e t h a n t h e o n e s from E x p e r i m e n t . d iscounted s o i l G eorgia, po unds p e r a c r e , lev els c a l c i u m c a r b o n a t e was 18 p e r c e n t s u p e r p h o s p h a t e a t 4 0 0 p o un ds t o t h e h i g h l e v e l , a n d 200 p o u n ds o f 50 p e r c e n t m uriate of p o ta s h t o the h ig h l e v e l . Low l e v e l s of phosphorus and p o t a s s i u m r e c e i v e d no a d d i t i o n s o f t h e s e e l e m e n t s . S ixty- f o u r h a l f - p l a n t s w ere u s e d w h ic h would h a v e p e r m i t t e d t h i r t y - t w o c o m p a r i s o n s b a s e d on d i f f e r e n c e s r e s u l t i n g from any one o f t h e elem ent v a r i a b l e s . fo llo w in g ta b le. A p a r t i a l plan of the d esig n i s g iv e n in the -92- TABLE XXIII DESIGN OF NUTRIENT LEVEL EXPERIMENT T r e a tment C o m p a r is o n s P lant P lan t P lan t P lan t P lant P lant P lan t A* A-,* B Bx C C1 D E E1 F F1 Gr G1 H Plant Dx ^Paired l e t t e r s r e p r e s e n t i d e n t i c a l p la n ts The d e s i g n a s p r e s e n t e d o f f e r e d a s a t i s f a c t o r y f o r a f a c t o r i a l w h i c h c o u l d n o t be u s e d , an i n c o m p l e t e b l o c k i n t h a t a l o s s su b stitu te and had an a d v a n t a g e o v e r o f p l a n t s w ould n o t s e r i o u s l y a f f e c t t h e e x p e r i m e n t u n l e s s t o o many p l a n t s o f one c o m o a r i s o n were l o s t . A ll p lan ts i n t h e t e s t were grown t o m a t u r i t y and t r e a t e d i n t h e u s u a l manner e x c e p t t h a t t h e s e e d were n o t g r a d e d f o r s i z e . The l o w y i e l d s of s e e d p r o d u c e d made i t n e c e s s a r y t o com bine p l a n t s i n t h e same c o m p a r i s o n t o o b t a i n e n ough f o r g e r m i n a t i o n purposes. When t h i s was done e a c h h a l f amount f o r t h e t e s t s . were o b t a i n e d . c o n t r i b u t e d an e q u a l By s o d o i n g f o u r c o m p l e t e r e p l i c a t i o n s A ll p lan ts, a f t e r seed h a r v e s t, were s a v e d f o r m i n e r a l a n a l y s i s p r o v i d e d any t r e a t m e n t e f f e c t s were d e t e r m i n e d by g e r m i n a t i o n t e s t s . -93- R e s u l t s and D i s c u s s i o n The e f f i c i e n c y o f t h e above d e s i g n p r o v e d t o be o u i t e sa tisfa cto ry for iso la tin g g iv e s the r e s u l t s s i n g l e elem ent e f f e c t s . T a b l e XXIV o f the g erm in a tio n t e s t s wherein the i d e n t i t y of in d i v i d u a l p l a n t s i s l o s t by c o m b in i n g them i n t o r e p l i c a t i o n s . TABLE XXIV EFFECT OF NUTRIENT LEVELS ON PERMEABILITY R e p .* 1 2 3 4 Means Rep.* W i ?3 76 94 76 79.7 W i P er cen t G erm ination Comparison 1 * C om p ar iso n 2 ; CpP K ; D i f f . D iff. ° 1 P 1 K 2 I G2 P 2 K 1 j • Cj Kj (C • 63 10 67 9 75 19 87 -13 73.0 + 6.25 C o m p a r is o n 3 : CgP-jKg : D i f f . 97 93 59 1 00 87.2 CiP2 k2 92 5 80 13 29 30 95 5 74.2 + 13.0 C o m pariso n 4 \ G2 P 1 ^ 1 j D i f f . 92 76 77 15 92 71 81 75 8 83 78 98 84 13 97 3 100 98 91 4 83 8 8 8.7 79.7 * 11.0 Means 90.1 Two p l a n t s i n e a c h r e p l i c a t i o n o f e a c h c o m p a r i s o n 10 CD -16 • 1 2 20 2 4.0 E x c e p t i n g tw o i n s t a n c e s t h e h i g h e r d e g r e e o f i m p e r m e a b i l i t y i s a s s o c i a t e d w ith th e h ig h e r l e v e l of calciu m . the d i f f e r e n c e s a r e as l a r g e In th r e e c a s e s as t h o s e used t o s e p a r a t e p a r e n t s in the in b r e e d in g stu d y r e p o r te d a b o v e . Had t h e h i g h e r p h o s p h o r u s -94- l e v e l b e e n t h e m ain f a c t o r c o n t r i b u t i n g t o s e e d i m p e r m e a b i l i t y , t h e ^]_^>2 ^ 1 ' an<3- ^ 3_^2 ^ 2 ^'■I:>ea^nieri"ts s h o u l d h a v e r e s u l t e d i n t h e h i g h e r amount o f im p e r m e a b l e s e e d . t r e a t m e n t C^PgKg, was t h i s I n o n l y one i n s t a n c e , the ca se. If in the h ig h e r l e v e l of p o t a s s i u m were t h e m os t i n f l u e n t i a l f a c t o r i n t h i s r e s p e c t , t r e a t m e n t s C-jP-^Kg, and should have Produced th e h ig h e r amount o f i m p e r m e a b l e s e e d . one r e p l i c a t i o n The r e v e r s e was t r u e e x c e o t t h e i n t r e a t m e n t C]PgKg. I t may be n o t e d i n t h e a n a l y s i s o f v a r i a n c e i n T a b l e XXV t h a t there i s six teen p a irs a h i g h l y s i g n i f i c a n t d i f f e r e n c e between the of com parisons. TABLE XXV ANALYSIS OF VARIANCE OF DATA IN TABLE XXIV • « : D. Source Total Groups P airs C o m p a r iso n 1 " 2 " 3 ii 4 Errop • 9 • • F. 31 3 12 1 1 1 1 12 : Sums o f S q u a r e s 6 ,7 2 6 .4 ? 528.00 4 ,6 9 2 .9 92.2 338.0 242.0 32.0 799.3? : i V ariance 176.0 291.32 92.2 338.0 242.0 32.0 66.61 : F 4.37' 5.0 7 ' T h a t t h e e f f e c t on p e r m e a b i l i t y can be a t t r i b u t e d t o calcium i s the p la n t s t r e n g t h e n e d by t h e h i g h e r p e r c e n t a g e o f c a l c i u m i n tissu e. Two r e p l i c a t i o n s o f t h e m a t e r i a l w ere combined -95- to o b t a i n enough m a t e r i a l f o r the a n a ly s e s . T a b l e XXVI g i v e s t h e means o f d u p l i c a t e d e t e r m i n a t i o n s f o r e a c h o f t h e a n a l y s e s . The d i f f e r e n c e s o b t a i n e d a r e n o t l a r g e e n ou gh t o e s t a b l i s h sta tistica l sig n ifica n ce even though the h ig h e r c a lc iu m l e v e l p l a n t s c o n t a i n e d o n e - t h i r d more c a l c i u m t h a n t h e low l e v e l p lan ts. The f a i l u r e to e s ta b lis h s i g n i f i c a n c e can be a t t r i b u t e d to th e i n c o n s i s t e n c y o f the r e s u l t s in the f i r s t comparison in r e p l i c a t i o n on e and t h e s e c o n d i n r e p l i c a t i o n tw o. The r e s u l t s o f t h i s e x p e r i m e n t do n o t con form t o t h e o b s e r v a ­ tio n s of H arrington b ility . (6 ) r e l a t i v e When t h e e f f e c t to the e f f e c t of s o i l s on p erm ea­ o f c a l c i u m on c e l l p e r m e a b i l i t y (18) is taken i n t o c o n s i d e r a t i o n th e h ig h e r d egree o f im p e r m e a b ility r e s u l t i n g from th e h ig h c a lc iu m tr e a tm e n t s h o u ld have been a n ticip a ted . The l o w e r c a l c i u m c o n t e n t o f c o a s t a l p l a i n s as c om p ared t o t h e h e a v i e r p i e d m o n t t y p e s i n t h e v i c i n i t y Experim ent, G eorgia, so ils of s tr e n g th e n s the assum ption th a t the h ig h e r d e g r e e o f i m p e r m e a b i l i t y o f s o u t h G e o r g i a s e e d may be a t t r i b u t e d t o m o i s t u r e and t e m p e r a t u r e d i f f e r e n c e s . The a g r o n o m i c i m p l i c a t i o n s o f t h e s e r e s u l t s note. so il Lime i s is n o t g e n e r a l l y recommended f o r t h e c r o p u n l e s s d istin ctly acid a lib e r a l a p p lication by v i r t u e are worthy o f (1, 13). I t w ould a p p e a r , h o w e v e r , the that o f l i m e w ou ld a i d i n m a i n t a i n i n g a s t a n d o f t h e g r e a t e r amount o f h a r d s e e d p r o d u c e d . A lso tne i n f r e q u e n t u s e o f t h i s amendment may p a r t i a l l y e x p l a i n t h e s h o r t lon gevity o f s t a n d s when o n c e e s t a b l i s h e d . -96- TABLE XXVI CALCIUM CONTENT OF PLANTS AS AFFECTED BY LEVELS OF APPLICATION P e r Cent C a lc iu m O xid e Treatm ent H e u l i c a t i on • • 1 • 2 : • Mean D if. 2 .7 3 * 1.87 2.30 2.1 8 1 .8 7 2 . 58 2.99 2.37 2.30 2.58 C1 P 2 K 1 C2 P i K 2 1.72 1 . 8 6 1.79 2 . 2 2 2 . 2 1 2 . 2 2 0.43 ° 1 P2 K 2 C2 p 1 k 1 1 .5 4 2.23 1.81 4.28 1.67 3.25 1.58 W i GgPgKg CiPiKg CoPgKi Means f o r C a l c i u m L e v e l s = L .S.D . = Cj - 1 . 9 7 , 0 . 1 2 2 . 1 2 2.48 Cg - 2 . 6 4 . 7 5 ©5% *Ea.ch a . n a l y s i s on m a t e r i a l from f o u r o l a n t s . 0.36 -97- MQISTURE CONTENT OF SEED Methods and M a t e r i a l s When t h e a n a t o m i c a l i n v e s t i g a t i o n s r e n o r t e d ab ove were i n P r o g r e s s an a i r it " as o b s e r v e d t h a t a l m o s t i n v a r i a b l y , s p a c e o c c u r r e d b e t w e e n t h e s e e d c o a t and c o t y l e d o n s . The p o s s i b i l i t y a r o s e t h a t d e l a y e d g e r m i n a t i o n m i g h t be c a u s e d by t h e i n a b i l i t y o f t h e w a t e r i m b i b e d by t h e s e e d c o a t t o c r o s s t h i s a i r s p a c e and i n i t i a t e germ ination. I t mas a l s o d e d u c e d t h a t l o w e r e d m o i s t u r e i n t h e s e e d vo u l d b r i n g a b o u t a sh r in k a g e of th e c o t y le d o n s broadening the s e p a r a t io n . S e e d o f r e l a t i v e l y h i g h m o i s t u r e c o n t e n t w er e d r i e d i n a d e s i c c a t o r and s pj n o le s w it h d r a w n a t i n t e r v a l s exam ination. for Tw en ty s e e d s a t e a c h m o i s t u r e c o n t e n t were h a l v e d by p l a c i n g t h e s e e d i n a s p e c i a l l y h o l d e r and c u t t i n g a c r o s s the hilum . c o n s t r u c t e d wooden One h a l f o f e a c h s e e d was p l a c e d u n d er a s t e r o s c o o i c m i c r o s c o p e , l u c i d a draw ing, a t 90 d i a m e t e r s , made of and a cam era the cut s u r f a c e . M e a s u r e m e n t s w e r e made ^t f i v e u n i f o r m i t y s e l e c t e d p o r t i o n s o f t h e d r a w i n g s and t h e a v e r a g e w i d t h d e t e r m i n e d . G e r m i n a t i o n t e s t s were run on a h u n d r e d s e e d a t e a c h m o i s t u r e l e v e l b u t t h e r e s u l t s a r e n o t r e p o r t e d o w in g t o t h e p o ssib ility tests o f becom ing perm eable in com bining. Germ ination were l a t e r run on s e e d w i t h d i f f e r e n t m o i s t u r e c o n t e n t s , h u l l e d as i n th e above e x p e r im e n t s . -98 R e s u l t s and D i s c u s s i o n It a o o e a r s o b v i o u s i n T a b l e XXVII t h a t d r y i n g t h e s e e d h a d no m a t e r i a l e f f e c t on t h e a i r c o t y l e d o n s and t h e s e e d c o a t . that im p erm eab ility i s space between the In v iew of the o r o b a b i l i t y c a u s e d by o t h e r f a c t o r s t h e d a t a has not been su b je c te d to c r i t i c a l exam ination. TABLE XXVII AIR SPACE BETY/EEN COTYLEDONS AND SExD COAT AS INFLUENCED BY MOISTURE Content P e r c e n t m o i s t u r e ___________ I Space in m icrons 13.2 1 0 .0 8 . 6 15.5 7.6 6 .5 6 .1 15.5 10.5 1 1 .1 On h an d h u l l e d s e e d t h e m o i s t u r e c o n t e n t d i d h a v e a c o n s i d e r a b l e e f f e c t a s shown i n T a b l e XXVI II. Several in vestigators (5 ,8 ,) h a v e shown t h a t d r y i n g o u t s e e d by t h e u s e o f h e a d makes s w e e t c l o v e r s e e d s more perm eable. On t h e o t h e r h a n d , Lebedefi (14) r e p o r t s that -99- TABLE XXVIII EFFECT OF MOISTURE COFTENT ON PERMEABILITY Percent M oisture ’ Rep. : Percent Permeable : : Means 12.9 13.0 87 83 85.0 2 1 8 . 1 8.5 78 77 77.5 2 1 5.4 5.4 75 75 _ ................... 75.0 1 2 ... 7 . 7 6 $ 9 1$ 4 . 2 3 $ 9 5$ ^ L. S ♦D.__ * ---------------------- b e a n s s l o w s up t h e r a t e o f m o i s t u r e a b s o r o - drying of f i e l d tio n . : : The s e e d o f c r i m s o n c l o v e r r e a c t t o d r y i n g i n t h e manner o f f i e l d beans in t h i s in p erm ea b ility o f 10 p e r c e n t . not s u f f i c i e n t s t u d y w i t h a maximum d e c r e a s e T h i s amount i n i t s e l f is to i n t e r f e r e m a t e r i a l l y w ith the s e l e c t i o n o f l i n e s d i f f e r i n g i n o e r m e a b i l i t y e x c e p t where c e r t a i n i n d i v i d u a l s may be on t h e b o r d e r l i n e o f l i m i t s cla ssify in g s e e d as perm eable or im permeable. presented s tr e s s The r e s u l t s the n e c e s s i t y of uniform s to r a g e c o n d i t i o n s from y e a r t o y e s r > p erm ea b ility . s e le c te d for if i n v e s t i g a t i o n s a r e bein«. c o n d u c t e d on - 100 - SUMMARY AND CUNCuUbloMS A natom ical i n v e s t i g a t i o n s of the seed coats of C r im s o n c l o v e r show them t o be s t r u c t u r a l l y s i m i l a r t o the seeds o f Red c l o v e r and t h e c e l l w a l l c o m p o s i t i o n l i k e th a t o f Sweet c l o v e r . a s a membrane i t 3y u s in g a d i s o r g a n i z e d seed c o a t was e s t a b l i s h e d t h a t I m p e r m e a b i l i t y i n C r im s o n c l o v e r i s p a r t i a l l y due t o t h e e x t e r n a l c u t i c l e la y er. Having found narked v a r i a b i l i t y among p l a n t s , i n h ar d s e e d e d n e s s b r e e d i n g e x p e r i m e n t s were i n i t i a t e d and c a r r i e d on o v e r a 3 - y e a r p e r i o d . Parental lin e s d iffe r in g i n p e r m e a b i l i t y were s e l e c t e d from t h r e e h u n d red p l a n t s s e l e c t e d a t random and s e l f e d . P a r e n t s f o r t h e s e c o n d and t h i r d g e n e r a t i o n were s e l e c t e d w i t h i n l i n e s from s e l f e d p r o g e n y on t h e b a s i s o f g e r m i n a t i o n t e s t s . The f i r s t h a r d , and s o f t - s e e d e d p a r e n t s s e l e c t e d w h i c h ha d a mean d i f f e r e n c e of 6 0 .3 p e r c e n t i n p e r m e a b ilit y w ith a germ ination of 2 5 .4 and 8 5 . 7 p e r c e n t , resp ectiv ely , y i e l d e d o r o g e n y w h ich d i f f e r e d i n mean p e r m e a b i l i t y by o n l y 0 . 3 0 p e r c e n t . Second g e n e r a t i o n p a r e n t s w i t h a mean d i f f e r e n c e o f 4 4 . 8 p e r c e n t i n p e r m e a b i l i t y p r o d u c e d s o f t - s e e d e d p r o g e n y w i t h a mean p erm eab ility of 7 6 .5 per c e n t, wrI t h a mean o f 72.8 per c e n t. and h a r d s e e d e d pro g e n y Third g e n e r a t i o n h a r d - s e e d e d p a r e n t s w i t h a mean g e r m i n a t i o n o f 3 6 . 7 o e r c e n t p r o d u c e d o f f s p r i n g w i t h a mean p e r m e a b i l i t y o f 8 4 . 7 p e r c e n t , and s o f t - s e e d e d p a r e n t s show ing 8 4 . 2 per c e n t perm eable s e e d s -1 0 1 - y i e l d e d o r o g e n y w i t h a mean p e r m e a b i l i t y Three y e a r s of per cent. 8 6 .5 o f s e l f i n g and s e l e c t i o n f o r l i n e s d i f f e r i n g i n p e r m e a b i l i t y c u l m i n a t e d w i t h a mean d i f f e r e n c e o f o n l y 1 . 6 1 per cent. E n v i r o n m e n t a l and p h y s i o l o g i c a l f a c t o r s in the f i e l d tio n s, stu d ied , and by p a i r e d c o m p a r i s o n s w i t h c l o n a l both separa­ s how ed t h a t s m a l l s e e d from f i e l d h a r v e s t s a r e more i m p e r m e a b l e t h a n l a r g e s e e d s p r o d u c e d u n d e r t h e same c o n d i ­ tio n s. A h ig h m oistu re su p p ly, v e r s u s a low s u p p ly , produced la r g e r seed w ith only a s l i g h t l y h ig h e r degree of p e r m e a b ility . S ev ere drought c o n d it io n s a p p aren tly r e s t r i c t e d stages the l a t e o f c e l l d i f f e r e n t i a t i o n w h ich r e s u l t i n i m p e r m e a b i l i t y . S e e d p r o d u c e d on heads su b ject to a h igh r e l a t i v e h u m id ity produced la r g e r s e e d t h a n h e a d s s u r r o u n d e d by a lo w r e l a t i v e h u m i d i t y . P l a n t r e s p o n s e a s t o p e r m e a b i l i t y was i n c o n ­ sisten t. The o d d s w er e 2 to 1 that heads su b je c t to a high r e l a t i v e h u m i d i t y w o u ld p r o d u c e s e e d 8 p e r c e n t more p e r m e a b l e t h a n t h o s e p r o d u c e d by h e a d s e x p o s e d t o a l o w r e l a t i v e h u m id ity. P l a n t s grown w i t h 2 0 0 0 f o o t - c a n d l e s o f i l l u m i n a t i o n p ro d u ced s e e d which did n o t d i f f e r from t h o s e produced i n f u l l A sig n ifica n t in s iz e or p e r m e a b i li t y su n ligh t. lin ea r relatio n sh ip was e s t a b l i s h e d f o r p e r m e a b i l i t y a s r e l a t e d t o h e a d s e q u e n c e and h i g h l y -102- sig n ifica n t c o r r e l a t i o n s were found b etw een head seq uence an d s e e d s i z e , and b e t w e e n s e e d s i z e and p e r m e a b i l i t y . When p l a n t s d id n o t h av e t o compete w ith a d j a c e n t v e g e t a t i o n , h e a d s e q u e n c e h a d no a f f e c t on p e r m e a b i l i t y . C l o v e r grown a t tw o l e v e l s of and p o t a s s i u m w e r e f o u n d t o be l e s s o f high l e v e l s of calcium , calcium , phosphorus, perm eable i n th e p r e s e n c e b u t u n a f f e c t e d by d i f f e r e n t l e v e l s o f phosphorus or p o ta ssiu m . S e e d w i t h 12 t o 1 3 p e r c e n t m o i s t u r e w e r e f o u n d t o be 1 0 p e r c e n t more p e r m e a b l e t h a n s e e d s d r i e d t o l o w e r m oistu re c o n te n ts w ithout h e a t. On t h e b a s i s o f t h e a b o v e i n v e s t i g a t i o n s i t appears t h a t t h e f o l l o w i n g c o n c l u s i o n s are j u s t i f i e d : 1. is p a r t i a l l y due t o t h e w e l l d e v e l o p e d c u t i c l e 2. p lan ts, layer. Wide v a r i a t i o n s i n p e r m e a b i l i t y e x i s t among fro m s e a s o n t o s e a s o n . 3. be I m p e r m e a b ilit y o f th e s e e d s o f crim son c l o v e r Im p e r m e a b ility of seed c o a ts does not appear to an i n h e r i t e d 4. ch ara cteristic. D i f f e r e n c e s in s o i l m oistu re l e v e l s , h u m i d i t i e s h a v e no c o n s i s t e n t e f f e c t 5. and r e l a t i v e on p e r m e a b i l i t y C r i m s o n c l o v e r p l a n t s d e v e l o p n o r m a l l y u n d e r an illu m in a tio n of 2 0 0 0 foot can dles. -105- A h igh le v e l effect f of calcium in the s o i l has the in c r e a s in g im p erm eability. S e e d become more im p e r m e a b l e a s t h e m o i s t u r e co n te n t of the seed i s low ered. LITERATURE CITED A lexander, E. D . , C r im s o n C l o v e r f o r f e r t i l i z e r , and s o i l p r o t e c t i o n . ______________________ ings of c e r ta in acre in G eorgia, and P r e s t o n , crops, B u ll. 844, use of m a t e r ia ls , 1950-1947. and M a r t i n , J . 1941, 95: H arrington, oo. 545-575, 19: seeds 5 7: D. A. Y e a r - of I.Ielilotu s 676, H. Yu'., A h u l l e r f o r c l o v e r h e a d s . 400-402, alba. treatm ent in 1915. Jour. Araer. 1945. L . , and K i n z e l , W . , The h a r d n e s s o f t h e s e e d Z e n t b l. Agr. abstracted Ghem. 56: 581-584, i n E. S . R. 1903.) H ollow ell, 160, U. S . D. A. 1952. ( O r i g i n a l not seen ; 642. U. S . G. T . , Hard c l o v e r s e e d and i t s c o a ts in L egum inaseae. 1907, II, 798-808. U. S . D. A. F ar m er s B u l l * Soc. Agron. H iltn er, 1947. N . , Sweet C lover se e d , Hamly, H. D. , S o f t e n i n g o f t h e H igbee, and o t h e r 1920. bbok o f A g r . h u llin g . 1958. 1959. and y i e l d s o e r Miraeo. C i r c . E. B . , C l i m a t e o f C o l o r a d o . Gaz. 452. Summary o f c l a n t - to im pervious seed s of sw eet c lo v e r . G ittin g s, Bot. B ., B u ll. and c h e m i c a l n a t u r e o f t h e s e e d c o a t and i t s Structure, rela tio n J. Ser. a s r e p o r t e d by c o u n t y a g e n t s , a g r ic u l t u r a l workers, Co e, H. S . , Ga. A g r . E x t . feed, E. A . , C r i m s o n c l o v e r , U. S. D. A. L f l t . -105- 10. Jam es, E . , A c l o v e r h u l l e r Amer. 11* Soc. Agron. 37: _____________ , E f f e c t f o r head sam nles. 158-160, of c e r ta in Jour. 1945. c u l t u r a l p r a c t i c e s on t h e c o n s e r v a t i o n o f m o is t u r e i n a oiedmont s o i l . Amer. S o c . 12. Johnson, Dept, 13. A g r o n . 3 7: G. C . , weather r e co rd s. o f Com. W e a t h e r B u r . , A thens, G eorgia. K ephart, L. V/., G row in g c r i m s o n c l o v e r . Lebedeff, 1142, Expt. i n common b e a n s 16. M artin, J. 326, the produc­ S ta. Res. B ui. 4, 1943. G olo. Agr. 1928. N. , The s t r u c t u r e and d e v e l o p m e n t of the seed c o a t and t h e c a u s e o f d elayed germ ination in L lelilotu s alba. 17. Bui. D. A. (P h aseolu s v u l g a r i s ) . Impermeable s e e d s o f a l f a l f a . Sta. S, 1922. P u e r to R ico Agr. E x o t. Lute, A ., U. U. 3 . G. A . , H e r e d i t y and e n v i r o n m e n t i n t io n of hard seeds 15. 1945. U npublished Farmers B u l l . 14. 945-952, Jour* Ia. Acad. S c i. Proc. ____________________ and W y a t t , 29: 345-346, 1922. J . R. , The s t r o p h i o l e and o th er seed s tr u c t u r e s a s s o c ia t e d w ith hard ness in 18. M e l i l o t u s a l b a L. and M. o f f i c i n a l i s W i l l d . S ci. 1944. Meyer, no. 19. 1 8: 457-469, B. L . , and A n d e r s o n , D. B . , 348-352. M iller, E. P lant M c G r a w - H i l l Book Co. In c ., 1938. 587. St. P h ysiology, New York: D. Van N o s t r a n d C o . , C., P la n t P h y s io lo g y , n. Ia. 1940. New York: Jour. -106- 20 . McKee, R. , V i t a l i t y and g e r m i n a t i o n o f c r i m s o n c l o v e r s e e d a s a f f e c t e d by s w e l l i n g and s p r o u t i n g and s u b ­ sequent drying. Jour. Amer. Soc. Agron. 27: 642-643, 1935. 21 . N e l s o n A . , Hard s e e d s i n L e g u m i n o s e a e . 804-805, 22 . Pammel, 1926. L. H . , L egum inoseae, Trans. 23. 24. Mature 118: St. A natom ical c h a r a c t e r s of the s e e d s of ch iefly t h e g e n e r a o f G ra y 's Manual. L o u is Acad. S ci. 9: P ieters, A. J . , and H o l l o v v e l l , U. S . D. A. Y e a r b o o k 1 9 3 7 , n o . P ieters, A. J . , 91-274, E. A . , 1899. C lo v e r improvement. 1190-1214. L e s p e d e z a s e r i c e a and o t h e r o e r e n n i a l l e s p e d e z a s f o r f o r a g e and s o i l c o n s e r v a t i o n . C ir. 25. 534, R e e v e , R. M. , S t r u c t u r a l c o m p o s i t i o n o f t h e s c l e r i d s 33: 191-204, S titt, Soc. 28. 36: S t u c k y , H. P . , 58th. U. S . D e p t , testin g . 29. E ffect W hite, of m oistu re, 464-467, s. C r im s o n c l o v e r s t r a i n s . An. R o t . , and Jour. pp. 63-64, Ga. A g r . U. S. D. A. Amer. Exot. 1946. o f A g r . , R u l e s and r e c o m m e n d a t i o n s f o r J ea n ., 21: Bot.. 1944. C ir. 480, seed 1938. The o c c u r e n c e o f an i m p e r m e a b l e c u t i c l e t h e e x t e r i o r o f some s e e d s . n. Jour. seed in g d a te, on t h e s t a n d s o f c r i m s o n c l o v e r . Agron. Sta. Amer. 1946. R. E . , fe rtilizer 27. S. D. A. 1939. i n t h e i n t e g u m e n t o f P is u m s a t i v u m L. 26. U. 203-210, 1908. Proc. Ro y. Soc. V i c t o r i a , on -10730. W in t o n K. B . , C o m p a r a t i v e h i s t o l o g y clover. B o t . Gaz. 57: 53-63, 1914. o f a l f a l f a and - 108 - APPENDIX A GERMINATION OF CRIMSON CLOVER PLANTS- SELFED IN 194 4 P lan t Number • « : 2 : 4 : 6 1 11 44 2 12 20 3 4 5 11 15 29 17 29 62 27 64 32 16 35 17 29 67 32 8 1 2 3 56 19 50 3 67 27 60 6 7 8 9 24 17 18 46 17 4 10 2 11 38 16 29 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 6 42 2 26 9 40 91 4 9 8 62 4 42 15 87 94 5 19 8 73 4 49 16 89 94 7 24 G e r m i n a t i o n by : 8 : 1 0 ";' 65 68 33 33 17 17 39 40 17 17 30 34 71 72 33 35 15 18 4 5 69 72 28 28 71 72 8 9 82 86 4 5 55 62 18 21 93 94 94 94 7 7 29 34 Day's 12 68 34 17 43 17 34 72 36 18 6 72 28 74 9 87 5 68 22 96 94 9 39 1 6 8 10 11 1 2 1 11 19 44 13 31 47 17 28 37 51 10 12 26 60 9 32 26 99 54 51 33 14 25 26 16 13 27 63 9 35 26 99 57 58 37 17 27 28 18 16 39 54 23 35 13 27 64 9 35 32 99 59 62 39 18 28 28 18 17 18 5 10 4 21 54 6 20 3 61 24 24 9 4 14 18 38 13 18 5 23 59 8 26 18 90 37 33 25 9 17 23 8 11 10 12 21 9 26 59 9 29 2 0 98 47 38 30 13 19 25 14 13 21 32 ; 14“ : 2 1 69 72 34 36 35 20 47 45 19 19 35 38 73 75 36 38 22 26 9 6 74 73 29 30 77 81 9 9 91 37 7 6 77 75 32 25 98 93 9 7 94 29 11 43 43 17 13 42 52 67 57 34 26 40 36 13 26 39 29 69 66 9 11 37 35 42 33 99 99 59 76 66 ?0 39 29 29 47 32 43 47 21 2 2 18 23 20 " ; 63 82 43 79 56 23 56 80 48 44 16 30 36 90 17 93 IQ 91 43 98 1 0 0 50 57 32 62 77 48 47 48 37 80 25 51 59 • 99 90 83 53 42 63 54 34 34 -109- APPENDIX A ( C o n t ’ cL) FTarTE Number 45 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 T : 43 50 13 67 28 4 28 36 23 38 24 52 62 17 83 30 10 11 40 45 27 40 28 61 64 18 87 32 16 8 1 2 2 18 20 17 36 21 7 5 15 42 4 13 : 6 6 11 16 54 5 18 21 20 21 21 21 8 12 23 32 23 47 14 41 26 15 45 31 78 19 26 7 18 59 36 91 27 36 13 7 57 79 69 25 54 18 59 36 92 28 38 13 7 58 79 69 25 54 22 2 2 38 38 2 2 25 5 7 4 3 12 9 15 1 1 20 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 43 47 11 20 8 6 5 5 11 1 2 11 22 59 7 66 11 5 4 31 62 55 14 35 13 25 6 8 8 16 18 7 6 6 46 49 78 65 68 56 19 42 16 31 1 2 17 1 2 1 2 6 2 .1 6 12 12 13 24 14 2 . 40 13 20 8 6 87 48 19 35 1 14 5 7 21 1 23 7 25 52 25 31 23 5 5 9 4 5 88 : g e r m i n a t i o n by Days : 8 : 10 : 12 : 49 56 56 64 71 72 38 44 46 43 44 46 33 31 32 69 77 74 65 66 6 6 19 18 20 8 8 92 95 39 33 38 17 22 23 14 22 22 11 14 14 27 24 26 62 65 65 9 9 8 26 10 30 61 30 41 28 5 23 31 15 1 18 13 32 17 32 63 34 47 35 5 29 37 16 1 18 13 36 17 32 65 36 53 36 5 31 41 17 14 59 74 51 47 35 80 67 21 95 40 27 24 14 28 65 9 28 29 61 38 92 34 42 14 9 61 80 69 27 54 23 43 : 21 60 79 60 54 42 89 69 24 97 49 39 38 21 32 72 14 35 50 75 52 94 38 64 17 18 64 84 78 79 61 28 47 1 6 23 14 38 18 38 28 17 47 27 44 70 45 74 54 66 39 60 40 5 33 45 18 : 63 63 88 72 65 49 96 77 33 99 57 51 57 29 61 84 23 47 81 89 74 95 62 82 22 36 76 86 89 46 84 43 52 21 51 43 61 51 54 74 63 92 77 6 6 37 61 26 65 70 62 -110- ( C o n t ' d.) 2 9 10 16 5 4 13 : 4 : 24 15 21 8 4 14 6 8 7 4 3 5 3 1 2 8 18 39 9 48 24 16 17 46 54 49 26 7 31 20 14 1 2 18 2 2 24 4 8 9 11 12 22 16 13 29 29 17 36 18 11 0 3 11 18 9 9 28 14 7 20 13 15 7 7 15 20 4 12 6 2 4 16 24 11 11 46 26 18 28 18 19 11 13 22 22 13 16 15 G e r m i n a t i o n by 6 : 8 : 10 : 34 38 48 17 2 2 23 38 41 43 14 20 20 7 4 7 17 14 17 9 1 0 10 17 18 18 4 4 4 9 1 2 13 9 9 9 19 15 25 28 36 33 42 44 43 12 14 14 59 60 54 30 29 26 17 17 18 20 25 23 79 69 86 59 64 62 72 64 75 29 30 33 37 40 44 20 24 26 39 44 43 30 38 23 3 2 3 5 5 5 19 18 18 27 27 26 12 1 2 15 18 18 16 60 69 75 40 46 53 29 24 31 39 32 35 34 26 31 27 22 24 25 15 14 25 19 25 27 32 34 27 28 23 19 16 23 47 29 42 1 ? 18 21 Days 7 17 14 : 54 24 45 26 7 17 10 11 18 4 14 18 4 14 10 10 25 37 44 14 60 31 18 27 84 65 75 34 44 26 44 40 3 5 19 27 16 18 76 54 31 41 36 27 16 25 34 28 24 49 23 25 37 44 14 60 31 18 27 1 2 52 23 45 22 : 86 65 75 34 44 26 44 40 3 5 19 27 16 18 76 54 31 41 36 27 16 25 34 28 24 49 23 63 70 38 59 41 17 27 25 18 8 53 22 33 62 59 24 86 49 32 52 72 91 91 57 61 43 63 56 22 15 38 38 30 47 94 91 44 54 77 47 42 57 70 34 APPENDIX A ( C o n t ' d ) P1 ant Number 135 136 137 139 13 9 14 0 141 142 143 144 145 14 6 14 7 148 14 9 150 15 1 152 153 15 4 15 5 156 157 15 8 159 16 0 16 1 162 163 164 16 5 166 167 168 169 170 171 172 173 17 4 175 176 177 178 179 180 l ___________________ G -e rm ln a t lo n by Days : 2 : 4 : 6 1 1 19 2 2 6 13 23 7 : 8 14 24 7 3 : 10 15 25 7 3 : 12 15 27 7 3 : 14 : 15 27 7 3 21 23 27 9 14 2 4 0 0 1 0 1 1 1 1 1 1 1 4 29 15 50 20 22 57 10 1 2 55 16 24 59 21 21 8 10 11 13 18 27 16 19 32 27 60 23 18 27 60 23 18 41 63 40 34 31 59 16 81 37 36 31 95 29 37 27 54 35 46 53 92 89 36 93 29 37 53 54 15 19 28 58 18 13 6 8 8 13 1 6 66 77 24 14 19 10 4 40 13 3 4 1 6 4 25 32 4 17 20 7 79 28 17 10 11 11 11 79 31 25 17 93 24 79 31 25 17 93 24 11 79 30 23 16 92 23 17 22 2 2 11 1 1 11 11 11 13 18 23 27 45 79 37 18 80 23 25 28 46 92 42 28 26 32 47 84 46 28 26 32 47 84 46 21 2 2 22 80 10 11 84 14 84 14 19 45 50 20 2 2 22 49 51 49 51 49 51 21 1 2 69 83 14 85 2 0 2 2 2 2 7 7 1 2 20 34- 79 29 8 6 20 34 9 20 1 2 21 6 38 69 16 15 56 7 8 12 35 47 43 78 27 17 70 9 17 39 49 8 1 1 1 2 12 12 1 2 12 4 9 17 11 12 12 18 28 14 2 0 21 36 16 37 16 14 25 41 16 15 25 42 16 16 25 45 16 1 2 27 27 46 8 8 7 11 8 11 9 8 1 2 1 2 9 15 23 54 15 3 39- 19 23 56 20 35 11 2 32 2 2 4 42 12 12 1 2 1 2 9 13 19 24 61 27 5 42 9 13 24 27 64 31 5 43 9 16 24 27 64 33 5 43 9 18 24 27 66 35 5 44 11 29 25 27 76 47 7 45 : 63 42 39 14 47 24 47 66 60 52 36 78 31 87 40 52 41 95 40 47 47 72 60 65 64 10 0 97 43 99 51 52 62 56 18 21 39 73 2 2 15 13 42 27 34 82 69 17 47 -112- APPENDIX A ( C o n t ’ d) P lan t Number 181 182 185 184 185 186 18? 188 1 89 1 90 1 91 192 19 3 194 19 5 196 197 198 199 2 0 0 2 0 1 2 0 2 203 204 205 206 207 208 209 2 1 0 2 1 1 2 1 2 213 214 215 216 217 218 219 I___________ 2 : 4 : 8 18 13 31 33 15 9 40 2 2 4 8 12 3 35 15 44 14 50 37 51 17 52 40 6 10 11 6 21 1 5 3 3 13 11 1 2 2 7 7 3 40 1 ? 3 37 37 13 25 18 7 3 9 13 3 28 2 0 9 18 16 4 5 tS 14 25 15 5 10 13 o 8 15 15 14 4 10 G e r m i n a t i o n by d a y s : 8 : 10 : 12 : 9 9 9 42 43 43 17 18 18 18 24 29 49 49 54 4 5 8 20 22 25 59 61 64 19 2 2 24 58 59 59 43 46 49 14 15 19 12 12 18 21 24 36 25 2.8 31 16 16 16 5 6 10 12 13 16 42 33 16 30 62 54 17 11 20 19 22 12 4 55 28 4 50 47 19 30 32 5 59 31 5 56 50 26 31 34 5 60 32 5 61 50 28 32 35 13 3 43 44 14 27 23 4 54 28 3 50 47 18 30 32 8 10 11 11 11 11 6 6 6 6 2 0 26 18 72 31 24 75 24 31 25 75 26 7 35 29 81 29 7 38 33 84 29 16 62 17 22 21 6 6 6 6 6 6 7 8 1 0 1 0 11 24 27 15 17 31 15 1 ? 20 22 23 48 19 60 60 85 8 8 16 10 11 11 14 13 14 26 4 44 59 85 14 16 19 32 15 17 15 17 8 8 2 2 1 3 47 10 41 53 79 75 22 11 1 0 11 20 8 11 12 2 2 2 29 64 24 59 50 13 56 19 49 64 19 35 64 37 64 76 46 18 33 57 11 6 2 2 1 2 1 11 9 11 14 : 10 11 9 23 6 11 227 9 39 1 ? 14 46 6 2 2 0 223 224 225 6 21 21 43 48 59 85 41 9 52 60 85 56 60 85 23 47 13 60 60 85 8 8 8 8 88 8 8 8 11 68 43 : 63 17 67 25 64 72 47 48 64 49 78 1 0 0 26 58 77 68 28 36 32 14 37 82 62 1 2 22 69 55 41 38 38 15 86 84 71 62 55 52 25 13 51 36 90 46 9 28 56 26 30 43 35 69 50 82 62 89 8 8 89 8 44 35 87 32 7 16 45 18 23 26 29 57 29 75 60 -..13- APPENDIX A ( C o n t ' d ) P lan t Number 22 8 22 9 23 0 231 23 2 233 234 235 236 23 7 238 239 240 241 242 243 24 4 24 5 246 247 248 24 9 25 0 25 1 252 253 254 25 5 256 257 25 8 259 260 261 262 26 3 26 4 265 266 267 268 269 2 70 271 272 » • : 2 : 91 74 82 67 61 52 24 73 45 88 73 56 14 32 26 46 16 50 30 64 37 70 46 51 57 37 58 70 62 35 39 77 67 90 67 86 81 78 69 68 62 67 64 63 72 4 : 93 78 87 81 68 56 28 74 46 95 85 58 15 35 26 47 20 53 31 67 37 75 48 56 61 37 59 72 63 38 39 77 72 90 67 86 83 78 70 68 62 74 70 67 75 _ 6 93 78 87 82 69 56 29 74 46 95 85 59 15 35 29 48 23 55 31 68 37 76 48 57 61 37 59 72 63 39 40 77 72 90 67 86 83 78 70 68 62 74 70 69 75 G e r m i n a t i o n bv Days : 8 : 10 : 12 : 93 93 93 78 78 79 87 87 88 82 82 82 69 69 70 56 . 57 57 29 29 29 74 74 75 46 46 46 95 95 95 85 85 85 59 60 60 15 15 15 35 35 35 29 29 30 51 53 54 24 29 25 60 56 62 31 31 31 69 69 70 37 37 37 77 77 77 49 49 49 57 57 57 61 61 61 37 37 37 60 59 59 72 72 72 63 63 63 39 41 41 41 41 41 79 77 77 72 73 72 90 90 90 68 68 68 86 86 86 83 83 83 78 80 78 70 70 70 68 68 68 62 62 62 74 74 74 70 70 70 69 69 69 75 75 75 ■ 14 : 21 : 94 93 79 79 88 88 82 83 70 70 57 57 29 29 78 75 46 46 95 95 85 85 60 60 17 15 35 35 30 33 54 56 29 36 62 65 31 31 70 74 37 37 77 78 49 51 57 57 66 61 37 37 60 61 72 73 63 65 41 42 41 41 77 78 73 73 90 90 69 68 86 86 83 83 80 83 71 70 68 68 62 62 75 74 70 70 69 69 75 75 63 95 80 89 85 73 60 30 79 47 95 88 69 22 37 43 63 46 71 32 82 39 79 56 60 78 38 62 84 66 44 42 82 75 90 71 86 84 36 72 69 62 76 71 70 77 “ j 14 APPENDIX A (Cont'd) P lan t Number 273 274 275 276 277 278 279 280 281 282 2 83 284 285 2 86 287 288 289 290 291 292 2.93 294 295 296 297 298 299 300 301 302 303 Mean • • : G e r m i n a t i o n by Days 2 : 4 : 6 : 8 : 19 12 : 14 : 21 : 63 57 57 58 58 58 60 58 58 64 62 69 69 69 69 69 79 69 75 75 75 75 75 75 75 75 76 81 73 74 74 74 74 74 74 74 75 59 59 60 60 60 60 50 60 63 77 79 79 79 79 79 79 79 81 83 84 84 84 84 84 84 84 84 70 70 70 70 70 70 71 70 71 76 76 76 76 76 77 76 76 76 59 59 59 59 59 59 59 59 59 54 55 55 55 55 55 55 56 56 72 72 72 72 72 72 72 72 76 70 84 84 84 84 84 84 85 86 42 43 43 44 44 44 44 44 45 56 55 56 56 56 56 56 57 56 32 32 33 34 34 37 35 35 43 90 84 90 90 90 90 90 90 91 93 93 93 93 93 93 93 93 93 87 92 92 93 93 93 93 93 93 98 100 100 100 1 00 100 100 100 100 87 87 87 87 87 87 87 87 88 33 33 34 34 34 34 34 34 36 50 52 52 52 52 52 52 52 52 79 82 83 83 83 83 83 83 84 89 90 90 3D 90 90 91 90 94 84 87 87 86 87 87 87 86 87 97 97 97 97 97 97 97 97 97 79 82 82 82 82 82 82 82 82 97 97 97 97 97 97 97 97 97 69 69 69 69 69 69 69 69 70 74 75 75 75 75 75 75 75 76 34.0 37.1 27.4 49.1 39.5 41.4 42 .4 43.5 57.8 -115- APPENDIX b RELATIVE HUMIDITIES AT ATHENS, GEORGIA DURING PERIODS OF SEED DEVELOPMENT OF CRIMSON CLOVER P eriod : Y ea r : 1:50 A .M .: Time 7 : 3 0 A.M. : 1:30 P .M .: 7 : 3 0 P.M. At>r. 1 4 - 3 3 1945 1946 194^ 82.2 % 79.5 82.7 89.7 % 83.0 84.5 60.4 % 44.3 47.8 75.3 % 53.7 59.6 May 1 - 5 1 1945 1946 1947 76.2 86.4 80.4 84.9 87.1 82.0 52.0 55.3 48.0 87.4 6 8 .8 58.8 APPENDIX C RELATIVE HUMIDITIES IN CHAMBERS DEVISED FOR HUMIDITY STUDY ■'"«i —'■ A ir tenq • 71 74 75 75 87 79 84 82 79 85 75 R e l. hum idity Dry : M o i s t 56 36 37 43 20 39 34 37 29 58 46 73 76 72 71 63 78 72 76 72 83 85 : : A ir temr. 65 75 69 80 75 82 78 77 72 73 76 : : R el. hum idity Dry : M oist 49 45 43 17 63 37 38 32 36 58 53 74 82 80 67 78 66 82 82 75 72 86 -116APPENDIX D GERMINATION OF CRIMSON GLOVER STRAINS AT EXPERIMENT AND TIFTON, GEORGIA IN 1 9 4 6 , AND 1 9 4 ? 1946 : Experim ent : S tra in A llen Thornton Hardy C o m m e r c ia l D ixie 100 96 85 67 T ifton _______1 9 4 ? Experim ent T ifton 80 89 68 93 62.5 61.5 APPENDIX E MEAN TEMPERATURES AND RAINFALL AT EXPERIMENT AMD TIFTON, GEORGIA DURING PERIODS OF SEED DEVELOPMENT IN CRIMSON GLOVER — ' ■ • P eriod ..lean E1 A p r.14-30,1946 May 1 - 3 1 Temperatures Maximum:Mean H in lm u it : E : ~1T : : TP 75 79 79 84 53 59 54 63 T otals A p r.1 4 -3 0 ,1 9 4 7 May 1 - 3 1 T otals 1. E x p e r i m e n t . 2 . 74 80 T ifton 79 85 52 58 54 63 Inches R a in fa ll E : T 1.74 5.79 2.51 3.82 7.53 6.33 3.42 5.02 4.16 2.5? 8.4 4 6.73