Assessment of relative abundance of black thrips, Thrips parvispinus (Karny) in major chilli growing areas of Karnataka

Abstract

A survey was conducted across major chilli growing districts of Karnataka such as Kolar, Mysuru, Haveri, Bellary, Raichur, Belagavi and Bagalkot to assess the relative abundance of different thrips species occurring on chilli. The collected thrips specimens from these localities were submitted to the taxonomist for identification. Results revealed that, totally six thrips species such as Thrips parvispinus Karny, Scirtothrips dorsalis Hood, Thrips palmi Karny, Frankliniella schultzei Trybom, Thrips florum Schumtz and Thrips hawaiiensis Morgan were recorded from these surveyed districts. Among these species, Thrips parvispinus Karny found to be dominated, which accounts for over 93.87 per cent of the total thrips population recorded in all surveyed regions, followed by Scirtothrips dorsalis Hood (22.75%), Thrips palmi Karny (0.64%), Frankliniella schultzei Trybom (0.25%), Thrips florum Schumtz (0.31%) and Thrips hawaiiensis Morgan (0.27%). The high prevalence of T. parvispinus across surveyed districts may be due to its exceptional adaptability to different weather conditions prevailing in chilli growing areas, favorable host availability and also limited natural predation or parasitization. Hence, the present study underscores the need for targeted pest management strategies focused on the dominant species T. parvispinus to mitigate potential yield losses in chilli production, while monitoring the regional prevalence of secondary thrips species to ensure comprehensive pest control measures.