Seasonal incidence of pink bollworm in relation to weather parameters in Bt cotton

The results indicated that the rosette flower damage, green boll damage, pink bollworm larval population per 20 green bolls, locule damage and open bolls damage in Bt cotton ranged from 2.10 to 44.50%, 5.00 to 55.00%, 1.00 to 18.00 larvae per 20 green bolls, 29.18 to 55.36% and 33.56 to 56.70% during kharif 2019–2020 and 5.35 to 49.60%, 5.00 to 65.00%, 3.00 to 25.00 larvae per 20 green bolls 46.07 to 65.34% and 41.80 to 58.10% during 2020–21, respectively. The peak of rosette flower damage, green boll damage, pink bollworm larval population per 20 green bolls, locule damage and open bolls damage was observed during 44^th and 43^rd, 45^th and 44^th, 46^th and 44^th, 50^th and 50^th SMW during both years 2019–20 and 2020–21 in Bt cotton, respectively. The Pink Bollworm population had a significant positive correlation with maximum temperature, minimum temperature, evaporation and bright sunshine and significant negative correlation with rainfall, wind speed and relative humidity.