Analysis of the Thrips Fauna (Insecta: Thysanoptera) on Flowers of Roses in Western Part of Romania

Abstract

Thrips are tiny insects responsible for the reduction of rose flower quality. Thrips are usually associated with roses particularly early in the season. Infestations concentrate around new flowers and flowers buds. During outbreaks these insects reduce flowers size and may even kill buds. Thrips fed especially on flowers petals after bud break, causing losses in blossom quality. This research work covers the observations of the species composition of thrips and the periods of the occurrence of the particulars species of thrips and their numerousness. Studies of Thysanoptera were realized at the Young Naturalists Station in Timisoara, on five rose varieties (Virgo, Pascaly, Golden Shower, Gloria Day and Flamingo), over the years 2012 - 2014. In order to achieve the objectives set were used the  flowers and flowers buds collecting method. Thrips fed especially on flowers petals after bud break, causing losses in blossom quality. This research work covers the observations of the species composition of thrips and the periods of the occurrence of the particulars species of thrips and their numerousness. The analysis of the thrips specific diversity pointed out a taxonomic spectrum of 12 species, four of those species of thrips, Frankliniella intonsa, Taeniothrips inconsequens, Thrips fuscipennis and Thrips major var. banatica, were recorded as the most important insect pest on rose in western part of Romania. Regarding to the geographical distribution, our studies highlights the dominance of the West-Palaeartic elements.