445 



weekly from June 14 to July 10. Adult emergence from all infested squares was 

 reduced 98%. .nis experiment demonstrated that the field population of boll 

 weevils was drastically suppressed by sterilizing the females so as to prevent 

 the development of the F, generation. 



872. , and Hopkins, A. R. 1977. A comparison of toxaphene + DDT + methyl 

 parathlon with presently recommended and experimental insecticides for 

 control of cotton pests in South Carolina. Proc. 1977 Beltwide Cotton 

 Prod. Res. Conf., pp. 147-148. 



A field test comparing toxaphene + DDT, toxaphene + methyl parathion + chlor- 

 diraeform, EPN + methyl parathion + chlordimeform, permethrin, fenvalerate, sul- 

 profos + azinphosmethyl indicated equal control of Heliothis spp. and boll wee- 

 vil Anthonomus grandis during early and mid-season. However, more effective late / 

 season control of Heliothis spp. and beet armyvorras, Spodoptera exigua by the 

 fenvalerate treatment resulted in greater yield from these plots when compared 

 to the toxaphene + DDT + methyl parathion treated plots. J 



873. , and Hopkins, A. R. 1978. Boll weevils: effects of various numbers 

 of Leggett traps on small and large populations. J. Econ. Entomol. 71: 



*598-600. 

 Neither a small nor a large population of Anthonomus grandis Boheman was sup- 

 pressed by from 10-80 pheromone traps/ha though the optimum number of traps/ha 

 (greatest number of weevils captured/trap) was determined to be 20 for a large 

 population. The regression of square infestation on trap capture was best ex- 

 pressed by the equation y = 0.09 + .048X. During the 1st and 2nd week of trapping 

 (prior to squaring), captures within the field were clumped and fit a negative 

 binominal distribution. Eighty Z of the total weevils were captured and 75% of 

 the punctured squares were found in a 20-m-wide belt around a cotton field. 

 Boll weevil pheromone traps therefore can function alone only as a survey and 



