Abundance of Cotton Aphids (Homoptera: Aphididae) and Associated Biological Control Agents on Six Cotton Cultivars

The seasonal abundance patterns of the cotton aphid, Aphis gossypii Glover, and its complex of biological control agents on six cotton cultivars differed among cultivars during much of the growing season. Differences in aphid populations among cultivars were >3-fold during the period of peak aphid abundance. Lower aphid densities were found on cultivars exhibiting the smooth-leaf character. Parasitism and predation may have reduced cotton aphid population growth early in the season. Entomopathogen infection was the primary cause of an aphid population reduction that occurred during the week after peak aphid abundance, and continued pathogen activity combined with predation maintained aphids at a low density for the remainder of the season.