Changes in the species composition of thrips onTrifolium repens(Fabales)

Abstract

Trifolium repens Linn (white clover) is the main host of several economically important thrips species in Yunnan Province, in China. The diversity and relative abundance of thrips found on white clover were surveyed weekly via destructive collections from May 2009–May 2010 in Kunming. The 1786 thrips adults were collected and prepared on slides, eight thrips species were identified. The predominant species was western flower thrips (Frankliniella occidentalis), then followed by Megalurothrips distalis, Thrips flavus, Frankliniella intonsa, Thrips palmi, Thrips hawaiiensis, Thrips tabaci and Megalurothrips usitatus. The largest variation in abundance occurred in Mid-Autumn and late Winter, with Thrips flavus dominant at Mid-Autumn and Megalurothrips distalis dominant at late Winter. The correlativity results showed that the population of western flower thrips was significantly negatively correlated to the population of M. distalis (P<0.01), and no significant correlation was found between the population of western flower thrips and the other thrips (P>0.05) in Summer of 2009. In Spring of 2010, the population of western flower thrips was negatively correlated to the population of M. distalis (P<0.05), and it was no significant correlated to the population of the others thrips (P>0.05). However, no significant correlation was found between the population of western flower thrips and the others thrips (P>0.05) in both autumn and winter of 2009.