406 



weevil movement into cotton. Results of this study suggest that weevil 

 response to grandlure is a seasonally related phenomenon, not greatly in- 

 fluenced by competition from pheromone-producing male weevils in cotton. 



796. , and Bottrell, D. G. 1976. Seasonally related decline in response 

 of boll weevils to pheromone traps during mid-season. Em'iron. Entomol. 

 5: 783-787. 



The seasonal response of Anthonomus grandis Boheman to pheromone produced by 

 males of the species and the synthetic pheromone (grandlure) was investigated 

 in the Rolling Plains of Texas over a 6-yr period. Records were maintained 

 on numbers of boll weevils captured on traps located at various distances 

 from cotton fields. Weevil entry into grandlure-baited cotton was compared 

 to weevil response to traps. The last major period of overwintered weevil 

 response to the pheromone source during the spring and a subsequent decline 

 in response occurred about the same time during most years independent of the 

 pheromone location with respect to cotton. The similarity in weevil response 

 trends indicated that the presence of pheromone producing ^ weevils in cotton 

 was not a major causal factor in the decline in weevil response to traps. These 

 results contradict an earlier hypothesis stating that reduced response to traps 

 during mid-season is initiated by competition from ^ weevils inhabiting cotton 

 In the trapping area. The present study concludes that the decltne in weevil 

 response to traps in the spring is a seasonally related phenomenon regulated by 

 presently unknown factors but not by competition from pheromone-producing weevils 

 in cotton. 



797. ; Bottrell, D. G.; Adkisson, P. L.; and Mclntyre, R. C. 1975. An 

 appraisal of a 10-year effort to prevent western spread of the boll 

 weevil. Bull. Entomol. Soc. Am. 21: 6-11. 



Each year since 1964 a boll weevil, Anthonomus grandis Boheman, population 





