Occurrence of thrips in lisianthus cultivation at different protected cropconditions

Abstract

Damages caused by thrips (Thysanoptera) are a constant concern in greenhouse. In lisianthus, Eustomagrandiflorum (Raf.) Shinners (Gentianaceae), it may cause direct and indirect damage. Thrips can affect flowers aesthetics through feeding on their petals. This study aimed at to recording the thrips species associ­ated with lisianthus under protected cultivation, assessing differences in species composition among lisianthus cultivars and among different growing conditions. The experiment was conducted in commercial greenhouses in the “Floricultura Florist” company, municipality of DoisIrmãos, RS state. The experiment was conducted from January to February 2013, comparing four cultivars with different colors (Marina, Orange Flash, Tu 668 and Ace White) and two greenhouses with structural differences. Each flower bed (25mx1m) containing one cultivar (treatment) was divided into 5 plots in which 10 plants were randomly selected and evaluated from the opening of the first floral bud until the cut of the flowers. The most common thrips species were Frankliniellaschultzei and F. occidentalis. The different growing conditions influenced the amount and composition of thrips species collected. There was variation in the average number of thrips gathered from cultivated varieties. This paper presents the first record of thrips species on E. grandiflorum in greenhouse of Brazil.