Seasonal incidence of invasive thrips, Thrips parvispinus (Karny) infesting chilli

Abstract

The present investigation was carried out to study the seasonal incidence of invasive thrips infesting chilli at the Department of Entomology, Anand Agricultural University, Anand (Gujarat), during kharif-rabi, 2022-23 and 2023-24. Present study revealed invasive thrips incidence on chilli twigs began in October (43rd SMW) during kharif-rabi 2022-23, with population peaks in the 2nd (8.20 thrips/twig) and 8th SMW (9.00 thrips/twig), which declined by the 11th SMW (5.60 thrips/twig). Highly negative correlations were observed with morning vapour pressure (r = -0.67**) and minimum temperature (r = -0.51*). In the year 2023-24, infestation started in September (38th SMW) and peaked in December (49th SMW). The infestation exhibited a highly significant negative correlation with the maximum temperature, minimum temperature, morning vapour pressure, evening vapour pressure, and rainfall. On chilli flowers, the infestation began as soon as flowering began in November (48th SMW) during kharif-rabi, 2022-23. It peaked in January (1st SMW, 10.80 thrips/flower), and it showed a significant negative correlation with the maximum temperature (r = -0.52*). In kharif-rabi 2023–24, the infestation started in October (43rd SMW) and peaked in December (52nd SMW, 10.60 thrips/flower), showing significantly negative correlations with maximum temperatures, minimum temperatures, and morning vapor pressure. The incidence of black thrips persisted throughout the crop period in both years.