Studies on the Parasitoids of the Serpentine Leaf Miner, Liriomyza trifolii (Burgess) in Tomato Ecosystem under Mid Hill Condition of Himachal Pradesh

Abstract

The species diversity of parasitoids of the serpentine leaf miner, Liriomyza trifolii (Burgess) in tomato ecosystem was conducted under mid hill conditions of Himachal Pradesh during 2008–2010. The tomato leaves were collected periodically from June to September from three strata i.e. bottom, middle and top portion of the plants at random. During the course of study four species of larval parasitoids viz., Neochrysocharis formosa (Westwood), Diglyphus sp., Asecodes sp. and Chrysocharis sp. belonging to the family Eulophidae and one species of larval-pupal parasitoid, Opius sp. belonging to the family Braconidae were identified. These parasitoids were active throughout the cropping season and the parasitization ranged from 6.0 - 21.1, 19.4 - 28.6 and 13.6 - 23.1 per cent during 2008, 2009 and 2010, respectively. It was maximum (20.1 - 28.6%) during the month of August. Marginally higher parasitization (14.3 - 26.7%) was observed in the middle stratum of the foliage than in top (11.1 - 24.0%) or bottom (6.7 - 20.0%) stratum during all the three years of study. Among the larval parasitoids, N. formosa was the predominant species (81.5%), whereas, other parasitoids such as Diglyphus sp., Chrysocharis sp. and Asecodes sp. comprised of 7.4, 7.4 and 3.7 per cent of the total population of the larval parasitoids.