Population Distribution of Flower Thrips and the Western Flower Thrips (Thysanoptera: Thripidae) in Nectarines and their Relative Association with Injury to Fruit in the Southeastern United States2

Abstract

Thrips populations and injury attributed to thrips feeding on fruit surfaces was monitored in unsprayed middle Georgia nectarines during 1986 – 1988. The flower thrips, Frankliniella tritici (Fitch), the western flower thrips, Frankliniella occidentalis (Pergande), and the soybean thrips, Neohydatothrips variabilis (Beach), were the most abundant thrips species recovered from the orchard. Their relative abundance changed each year. The western flower thrips particularly appears to be most damaging in causing russeting on fruit surfaces. Silvering injury was caused by either or both of the flower thrips and coincided with peak populations of adults at or near final fruit swell. Soybean thrips caused little or no injury to fruit. None of the above mentioned flower thrips species were recovered from various weed and grass species in and near the nectarine orchard during two years of overwintering studies.