UTTAR PRADESH JOURNAL OF ZOOLOGY

This study was conducted to investigate ‘Seasonal diversity and abundance of predatory arthropods (Insect pests and Spiders) in Bt and non-Bt cotton fields of Nalgonda district, Telangana state, India’ at farmers fields of Palem village, Nakrekal mandal, Nalgonda district, Telangana state, India. Sweep net and hand-picking methods were used for the collection of predatory arthropods (Predatory insects and spiders) on Bt and non-Bt cotton plants. Predatory arthropod species were identified with the help of the Guide on Cotton Pests and Predators by RARS, PJTSAU Warangal and Literature. During the study period, 09 predatory insects and 02 spiders on Bt cotton and 11 predatory insects and 03 spiders on non-Bt cotton were observed, which belonged to 12 different insect families and 03 spider families in 07 different orders. The seasonal abundance was lower in both Bt and non-Bt crops in the month of July 2019; gradually increased from July 2019 to November 2019 and then decreased from December 2019 to January 2020 on both Bt cotton and non-Bt cotton fields We noticed small differences in diversity and abundance of predatory arthropods between non-Bt and Bt during the 2019-2020 cotton season. We found 2 species of predatory arthropods in July, 6 species in August, 9 species in September, 10 species in October, 11 species in November, 7 species in December and 9 species in January on Bt cotton and 2 species in July, 5 species in August, 10 species in September, 12 species in October, 12 species in November, 9 species in December and 9 species in January on non-Bt cotton fields during the 2019-2020 cotton cropping year. We found a lower number of species in Bt cotton in comparison to non-Bt cotton fields. Ecological indexes were calculated for analysis of community structure of predatory arthropods.