Vernalization 



AND PhOTOPERIODISM 



Plate 6 

 to face p. 86 



Fig. 3. — A vegetative Biloxi soybean plant, 42 days 

 old, grown under a long (14 hour) iihotoperiod. Con- 

 tinuous vegetative extension of stem. — Photographs by 

 tlie author. 



Fig. 4. — A reproductive Biloxi soybean plant, 42 days 

 old. grown under a short (7 hour) photoperiod. Termi- 

 nal extension had ceased 15 days before photo was 

 taken. Numerous short axillary shoots. 



Fig. 5. — Close-up of upper part of stem of reproduc- 

 tive plant shown in Fig. 4. Numerous pods, flowers 

 and buds on short axillary shoots. No terminal exten 

 sion of stem (photoperiodic inhibition). 



