Influence of abiotic factor on incidence of Pink bollworm, Pectinophora gossypiella (SAUNDERS) on Bt cotton

Abstract

The present research on "Influence of abiotic factor on incidence of pink bollworm, Pectinophora gossypiella (Saunders) infesting Bt cotton" was carried out at Village: Daliya, Ta. Gondal, Dist. Rajkot during Kharif, 2020-21. The results of experiment were revealed that percent rosette flower were continuously increased and get its first peak (12.80 percent/plant) during 40 th SMW and second peak (11.20 percent/plant) was observed on 45 th SMW, then declined up to the harvest of the crop. The maximum temperature and bright sunshine hours were significantly positively correlated with rosette flower. Larval population was increased and get its first peak (7.00 larvae/20 bolls) during 43 rd SMW. The second peak (7.00 larvae/20 bolls) was observed on 46 th SMW (23 rd WAS) and then declined up to the harvest of the crop. The bright sunshine hours was found highly significant and correlated positively with larval population. The morning and evening relative humidity were found highly significant with negative correlation, while the minimum temperature and wind velocity were found significant with negative correlation with larval population. Percent green boll damage were continuously increased and get its first peak (24.80 percent/plant) during 44 th SMW. The second peak (16.80 percent/plant) was observed on 48 th SMW and then declined continuously up to the harvest of the crop. The male moth caught from 26 th SMW (1.50 moths/trap/week) to 2 nd SMW (1.00 moths/trap/week) and ranged from 1.50 to 13.50 per trap/week during the entire crop period.