SEASONAL INCIDENCE OF RICE THRIPS Stenchaetothrips biformis (BAGNALL)

Abstract

Studies conducted at the Paddy Breeding Station, Coimbatore on the seasonal incidence of the rice thrips, Stenchaetothrips biformis in the rice nursery and the main field revealed a peak occurrence of the pest during the months of August and September. The pest population and its damage during the month of March were very low. The pop- ulation of thrips was higher on the weed host, Echinochloa colona during the month of March. Significant positive association was known to exist between thrips population and their damage (r=0.82) and regression equation Y 14.2 + 17.9X indicated that for an increase of one thrip, there would be an increase of 17.9% damage. The regression analyses revealed that an increase of 1% RH would increase the thrips population and their damage by 0.06 and 1.867% respectively as well as increase in sunshine by one hour would reduce the thrips population by 0.017 and their damage by 0.565% in the nursery. In the transplanted crop, increase in evening RH by 1% would increase the thrips population by 0.271 and their damage by 1.129 % as well as increase in sunshine by one hour would reduce thrips damage by 0.29%. The population of thrips on E. colona would be increased by 0.531 for every 1°C increase in minimum temperature.

DOI

https://doi.org/10.29321/MAJ.10.A02040

Pages

143 - 149

Creative Commons

Copyright

© The Author(s), 2025. Published by Madras Agricultural Students' Union in Madras Agricultural Journal (MAJ). This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited by the user.

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