■j"f.|k'*Ji!»" ' lyiv*" 



120 



extensively as a female chemosterilant. Egg production was suppressed when 

 females fed for only 6 days on diet containing the trihydroxy compound. None 

 of the weevils died, and there was little recovery of fertility. High temp- 

 eratures during treatment and addition of a synergist to the diet favored the 

 sterilizing action. The combined effects of y-irradiation and steriod treat- 

 ment were not completely additive, an indication that the 2 sterilizing agents 

 acted on a common target. Also, the steroid seemed to antagonize the action 

 of the chemosterilant busulfan (1,4-butanediol dimethanesulfonate) when both 

 were given in the diet of the adults. When given in the larval diet, 3 ppm of 

 the trihydroxy steroid lowered the yield of adults, and 10 ppm almost eliminated 

 the formation of adults. Deformities occurred at all stages of development. 



225. , and Simmons, L. A. 1979. Boll weevil: ability to fly affected by 



acetone, irradiation, and diflubenzuron. J. Econ. Entomol. 72: 573-575. 

 Observations in the field indicated that a large percentage of sterilized 

 Anthonomus grandis grand is Boheman were unable to fly from the soil surface 

 to nearby cotton plants. In laboratory tests, dipping in acetone or in an 

 acetone solution of diflubenzuron reduced flight ability by ca. 40%. Irra- 

 diation alone did not affect flight, but .ipint treatment with irradiation 

 plus a cetone reduced the number of flights by ca. 72%. Diflubenzuron reduced 

 flight when fed to newly-emerged adults on 4 consecutive days but not when fed 

 on the 4th day only. This delayed dietary treatment with diflubenzuron, com- 

 bined with irradiation with 10 krad in nitrogen, effectively suppressed female 

 fertility and had a minimal effect on the flight ability and mating capability 

 of males. 



1 t 



