151 



insects collected from treated plants with the Rb content of those from untreated 

 plants. Some entomophagous insect species were labeled with Rb, indicating the 

 Rb moved through the food chain from producers through primary to secondary con- 

 sumers. 



285. Graves, J. B.; Earle, N. W. ; Bradley, J. R. , Jr.; and Glower D. F. 

 1969. Field studies of an attractant in the male boll weevil. La. 

 Agric. 12(3): 14-15. 



Data from this study indicated that male boll weevils do emit an attractant (s) 

 to which both sexes of its species respond under certain conditions in the 

 field. Tne greatest response is obtained early in the season prior to plant 

 fruiting and late in the season when field weevils are being exposed to 

 diapause- inducing conditions. The attractant (s) would appear to be very 

 useful in survey and detection of boll weevilc and may well aid in their 

 control. 



286. ; Roussel, J. S.; Gibbens, J.; and Patton, D. 1967. Laboratory 

 studies on the development of resistance and cross-resistance in the 

 boll weevil. J. Econ. Entomol. 60: 47-50. 



Laboratory experiments were undertaken to determine if resistance could be 

 developed in the boll weevil, Anthonomus grand is Boheman, to a representative 

 chemical in each of 3 classes of insecticides now being used for its control. 

 The topical-application technique and insecticide-contaminated larval media 

 were the 2 methods of selection utilized. Selections for resistance to azinphos- 

 methyl and carbaryl, using the contaminated larval media, were unsuccessful. 

 However, selections for resistance utilizing the topical application of the 

 selective insecticides were successful in the cases of endrin and a 2:1 mixture 

 of toxaphene-DDT. ^■There endrin was used as the selective agent in 1 generation 

 and azinphosmethyl in the next generation for 27 generations, resistance was 



