Temporal Distribution and Abundance of the Coccinellid Complex as Related to Aphid Populations on Cotton in South-East Queensland.

Abstract

Population abundance data are given for coccinellid species as related to aphid presence on cotton in south-east Queensland. Coccinellids (and other aphidophagous species) have been observed to effectively maintain aphid numbers below crop-damaging levels in unsprayed cotton for three consecutive cotton seasons, two of which are reported here. Six species were recorded, forming a continuous and generally uniformly distributed species-complex which exhibited several functional characteristics necessary for successful aphidophagous predation in agricultural ecosystems. Five of these species responded to aphid presence by producing offspring. Insecticidal treatments for aphid control under similar circumstances in commercially grown cotton fields would be unwarranted.