100 THE PEANUT— THE UNPREDICTABLE LEGUME 



Liu and Lou^ were unsuccessful in stimulating the ovule into seed 

 development by means of a variety of substances, including auxins, vita- 

 mins and different plant extracts. Long immersion of the gynophore in 

 0.02 percent naphthalene acetic acid caused roots to develop just above 

 the undeveloped ovary. These workers were able to initiate fruit develop- 

 ment by grafting gynophore tips to detached cotyledons and culturing 

 them until the food supply of the cotyledons was exhausted. 



Jacobs* indicates that the auxin which diffuses out of excised tips of 

 gynophores exhibits polarity of transport, that is, moves only from ovary 

 end toward the proximal end of the gynophore. 



DORMANCY AND GERMINATION 



Hull and Stokes (44, 81) reported dormancy of the peanut seed to 

 be hereditary in nature and that the rest period of some seed might be 

 as long as 2 years. The rest period of seed of the Spanish and Valencia 

 types ranges from 9 to 50 days, while that of some runner types might 

 range from 110 to 210 days. Seed of the Spanish types will germinate 

 in the field unless harvested promptly after maturation. The longer 

 rest requirement of the runner type is desirable if peanuts are left in 

 the field to be "hogged off" during the fall or winter months. However, 

 difficulties in germination of the runner peanut are rarely encountered 

 since the rest requirement is satisfied in the interval between fall harvest- 

 ing and spring planting. Hull (44) reported that the time required for 

 breaking the rest period of Florida Runner and Spanish seed was in- 

 creased when stored at 3° C. and decreased when stored at 20° to 40° C. 

 A regular practice was followed of storing seed at 30° C. for 30 days after 

 harvest, when quick germination was desired. The data indicate that the 

 rest requirement of the peanut seed decreased as storage temperature 

 increased from 3° to 40° C. which is opposite of that required by seed of 

 many crops. 



Results by Beattie et al. (7) indicate that winter storage tempera- 

 tures of 32°, 40° and 70° F. had no significant effect on germination of 

 several varieties of seed tested. Unshelled, stored seed seemed to germin- 

 ate somewhat better than those shelled. Additional experiments to de- 

 termine the effect of age on germination were conducted with Valencia 

 and Improved Spanish varieties. When held at a storage temperature of 

 approximately 70° F. there was favorable germination of Valencia pea- 

 nuts for 5 years and of Spanish for 3 years, after which there was a dis- 



' Personal correspondence, Dr. P. S. Tang, dean. College of Agriculture, National Tsing Hua 

 University, Peiping, China. 



* Personal correspondence, W. P. Jacobs. 



