\ 



477 



Female Bracon mellltor Say responded to the frass cf diet-reared boll weevil 

 larvae by probing with the ovipositor. Similar responses were elicited by the 

 hexane and chloroform-methanol fractions after differential extraction of boll 

 weevil feces. The active component of the chloroform-methanol fraction was 

 identified as methyl £-hydroxybenzoate (methyl parasept) . Because the methyl 

 parasept is an artificial component of the diet, Che results suggest that the 

 parasitoid response may be associatively learned. The response to methyl para- 

 sept decreased with time in the absence of reinforcement. Results demonstrate 

 that certain chemicals may release behavior normally evoked by kairomones, and 

 may interfere with the isolation of natural kairomones. 



W 



9A2. Wade, L. J., and Rummcl, D. R. 1978. Boll weevil immigration into winter 

 habitat and subsequent spring and summer emergence. J. Econ. Entomol. 

 71: 173-178. 

 A study conducted from 1974 to 1977 revealed that emergence patterns of over- 

 wintered Anthonomus grandis Boheman were related to the time that boll weevils 

 entered winter habitat. The response of marked weevils to pheromone traps 

 during the spring and summer Indicates that weevils which enter overwintering 

 sites during the later half of the fall period tend to emerge later the follow- ,- 



ing growing season than those which enter hibernation early. Leaf litter exa- 



i 

 minations during the period Aug. 1975-Mar. 1977 indicate that the major build- ' ! 



up of overvintering weevils in hibernation sites occurs through Oct. and Nov. 



The association between the time of boll weevil entry into overwintering habitat 



and the time of emergence the following growing season is an important factor to 



consider in conducting late season boll weevil suppression programs. Data 



developed during this study indicate that field populations present during 



Oct. and IJov. should be subjected to maximum control pressure since they tend 



/ 



