434 



than cohorts started during July to mid-August. This fact indicates that adult 

 numbers should tend to accumulate in cotton fields after mid-August. 



850. , and Adkisson, P. L. 1971. Seasonal biology of the boll weevil in 

 the High and Rolling Plains of Texas as compared with previous bio- 

 logical studies of this insect. Ttx. Agric. Exp. Stn. Misc. Publ. 

 MP-993, 12 pp. 

 Field-cage and insectary studies provided data on developmental periods of boll 

 weevils reared on squares, bolls and a cottonseed meal diet. Egg to adult 

 developmental periods for square-reared boll weevils ranged from 13.6 to 52.5 

 days for adults developing from eggs deposited July 18 and August 10, respec- 

 tively. Boll-reared weevils required from 11 to 31 days longer than square- 

 reared weevils to develop to the adult stage with the developmental period 

 increasing as the season progressed. No adults developed from eggs implanted 

 after October 15 during both 1965 and 1966. Diet-reared boll weevils required 

 an egg to adult developmental period that ranged from 63 to 17 days for adults 

 developing from eggs deposited on March 17 and July 20, respectively. Average 

 ambient temperatures ranging from 54 to 87° F. apparently caused the egg to 

 adult developmental period to increase from 12.5 Lo».55 days for the two tempera- 

 tures, r espe ctively. Pre-oviposition periods ranged from 4 to 11 days for adults 

 developing from eggs deposited on July 3 and September 26, respectively. Also, 

 the egg to egg developmental periods ranged from 16 days to 52 days for adults 

 developing from eggs deposited on July 3 and September 26, respectively. 

 Variation in emergence periods Increased as the season progressed, 



851. , and Adkisson, P. L. 1978. Population dynamics of the boll weevil 

 inhabiting the High and Rolling Plains of Texas. Environ. Entomol. 

 7: 439-444. 



Seasonal field increases in the number of boll weevils in Dickens and Kent 



