Insecticide Usage in Panola and Pontotoc Counties, Mississippi, 1977-1980, During the Optimum Pest Management Trial

Abstract

Results of a study of insecticide usage for cotton insect control in the four-year period from 1977 to 1980 in Panola and Pontotoc Counties, Miss., indicated that insecticides were overemphasized in Panola County in 1977. Better management of insect populations had considerable influence in reducing the amount of insecticides used in that county thereafter. In Pontotoc, an underuse of insecticides was evident, especially when boll weevil, Anthonomus grandis grandis Boheman, infestations increased in 1979 and 1980. Control materials used in the two counties were two biological agents, Bacillus thuringiensis and Baculovirus heliothis, and 15 insecticides. The compounds used were those generally suited for control of the particular pest involved. The pyrethroids were first used in 1978 for control of the bollworm, Heliothis zea (Boddie), and tobacco budworm, H. virescens (F.). The addition of the Heliothis spp. ovicides, chlordimeform and methomyl, to other insecticides or mixtures of insecticides was apparent in 1980. Lighter Heliothis spp. infestations and increases in boll weevil infestations in 1979 resulted in a decline in the use of pyrethroids in favor of the use of the EPN or toxaphene plus methyl parathion mixture.