Species and Population Dynamics of Thrips Occurring Inside and Outside Greenhouses Cultivated with Roses in Southern France

Thrips are major pests on rose crops. Monitoring and dispersal of thrips populations is of significance for the development of effective integrated pest management programs. This study was conducted to survey thrips species and their population densities occurring inside and outside rose greenhouse from year 2006-2009 in France. Among 1,850 samples collected outside, 11,617 individuals belonged to 53 species. Among 316 samples collected inside the greenhouse 2,706 individuals belonged to 7 species. The predominant species were Thrips tabaci (Thripidae) and Frankliniella occidentalis (Thripidae). Rose crops were infested mainly in spring and at the end of autumn. In this study, Thrips australis and Scirtothrips inermis were identified for the first time in France. Increasing thrips populations inside the greenhouse were related to the peak of thrips abundances outside in the spring, at time of replacement of muslin cloth used to cover the entrance of greenhouse. In autumn, no correlation was observed between pest populations inside and outside the greenhouse, where individuals of thrips present in the greenhouse continued reproduction during this period. With our data, we hope to contribute to the gain of knowledge about thrips population dynamics inside and outside greenhouses in Southern Europe.