Survey of thrips in Sri Lanka: A checklist of thrips species, their distribution and host plants

Abstract

Thrips of Sri Lanka have been poorly studied despite their significance to agriculture and horticulture of the country. A survey of thrips and their host plants was conducted in several parts of Sri Lanka during 2005-2008, with a view to record the species present, their distribution, host plant relationships and damage caused. Over 1,000 plant species comprising crops, ornamental plants, weeds, shrubs, and trees were examined for thrips in 22 study sites, representing a range of habitats in nine districts covering 12 agrochemical regions of the country. Damage in plants due to thrips infestations was documented. This paper presents a list of 72 thrips species in 45 genera recorded during the survey from 324 host plant species in 83 plant families. Megalurothrips usitatus, Thrips palmi, and Haplothrips gowdeyi were the most widely distributed species. The grass infesting Haplothrips spp., several species of Thrips, Microcephalothrips abdominalis, M. usitatus and Scirtothrips dorsalis are some of the species with a large number of host records. Thrips simplex in particular was confined to the Upcountry Wet zone, while Thrips flavus was most widespread in this region and was present on almost all the vegetation. The survey identified 24 species of thrips represented in 20 genera that were not recorded previously from Sri Lanka. Majority of the thrips recorded are pest species, cosmopolitan in distribution. The most common damage due to thrips infestations was discolouration, scarring and browning of leaves and flowers, most pronounced in cut flowers. The survey updates the information on the Thysanoptera of Sri Lanka and highlights their importance in agriculture and floriculture.

Key words: agriculture; floriculture; damage; pest species; new records

DOI: http://dx.doi.org/10.4038/cjsbs.v40i2.3926

CJSBS 2011; 40(2): 89-108