'''^i^ M T» !F P «!^W i «« ' . i WW aw n-H I ■! .■ » I i jj i ^iL " ' —g » <■■ > ■ . ■ " v ' -*v . . ■>■■■»- * ■ ■ > V ' W y¥»*?^* ■!«■■ ■ <» i'*^ " T " ■ """ «wn> - "^ --•«»«■■>»— ^ ^ ■- ( ■ ^ y |^i y ,. i^» e i ^ i| T i y yni^r 



M W V !'' . '" ■«>^MW>W 



118 



221. ; McGovern, W. L. ; and Kearney, J. F. 1979. Pattern of distribution 



of ■^''■P-tagged, sterile male boll weevils dropped by plane. J. Ga. Entomol. 



Soc. 14: 269-277. 

 Boll weevils, Anthonomus grandis Boheman, were sterilized by ganima irradiation 

 in an atmosphere of nitrogen followed by a dip in an acetone solution of 



diflubenzuron. Both sexes were relased, but only the males were tagged with 



32 



P. The weevils fell in a band no wider than 3m when dropped over cotton 



from a plane flying at a height of 15m. Many of the weevils landed on the 

 ground, and a good portion of these died during the next 2 days, especially 

 in parts of the field where the plants offered the least shade. The acetone 

 treatment is believed to have partially inhibited flight capability, thereby 

 preventing many weevils from reaching the cotton plants. Once the males 

 began to feed, few of them moved from one row to the next. 



222. , and Nilakhe, S. S. 1977. Radiosensitivity of different stages of 

 spermatogenesis in the boll weevil. Ann. Entomol. Soc. Am. 70: 229-233. 



All cell stages of spermatogenic cells are found in the adult boll weevil, 

 Anthonomus grandis Boheman. We irradiated males and then allowed them to 

 mate daily with successive groups of virgin females. Variations in fertility 

 and in numbers of sperm produced were used as a basis for measuring changes 

 in resistance of germ cells to the induction of dominant lethal mutations 

 and to cell death. As expected, the various cell stages were not uniformly 

 resistant. Sperm utilized by males immediately after irradiation were mature 

 at the time of treatment. High doses of gamma irradiation were required to 

 suppress fertility, indicating a high degree of resistance to the induction of 

 dominant lethal mutations, llatings between the 3rd and 4th days after irradia- 

 tion produced the fewest progeny. Sperm maturing at this time probably deve- 

 loped from irradiated spermatids; this cell stage was about 10 times more sen- 



