Two Thrips Species in Durum Wheat Cultivations in the Region of Western Macedonia, Greece

Research Article
Two Thrips Species in Durum Wheat Cultivations in the Region of Western Macedonia, Greece

P.N. Deligeorgidis, N.P. Deligeorgidis, C.G. Ipsilandis, A. Vardiabasis, D. Stavridis, M. Vayopoulou and G. Sidiropoulos

Journal of Entomology, 2011, 8(5), 484-490.

Abstract

The purpose of this study was to monitor population fluctuations of two thrips species (Limothrips cerealium and Limothrips denticornis), during the growing season of durum wheat, in years 2009 and 2010. Samplings of insects were taken in eight periods to cover the late stages of durum wheat. Measurements were made every about 100 m in the field, with five wheat plants per sample, from 10 different places. Total thrips individuals (per species) on each wheat plant were counted. The species Lema melanopa was also included in measurements (to make comparisons between thrips species more independent). According to the results for all three insects studied, sampling period showed the greatest differences. L. denticornis and L. melanopa, showed a significant interaction between year and sampling periods, indicating different population fluctuations in the two years. L. cerealium showed a stable population fluctuation across years. L. denticornis, showed also differences in population across years. This unstable behavior may be a result of some specific enemies or competition phenomena between the two thrips species, since maximum values of the two species were recorded in different sampling periods. Maximum number of thrips individuals found on each plant was 7 for L. denticornis and 9 for L. cerealium but maximum average values were close to 2 for L. denticornis (in 6th sampling period) and 2.8-3.3 for L. cerealium (between 4th and 5th sampling period). The relatively low populations of thrips species found in this study did not resulted in significant and apparent damages in durum wheat cultivation but the economic threshold for L. denticornis and L. cerealium has to be decided in combination to other insect pest species.