SEASONAL ABUNDANCE AND DIVERSITY OF ARTHROPODS IN BT COTTON OF KALABURAGI, KARNATAKA, INDIA

Present study was conducted at Bt-cotton fields of selected study area of Kalaburagi. The results shows that, a total 21 arthropods were recorded, among them 13 insects were categorized as pests and 8 were natural enemies apart from that 3 species of predatory spiders were recorded. In Bt cotton agro-ecosystem leafhoppers, whiteflies, aphids, thrips, mites, and red cotton bugs were abundant during 35th, 36th, 40th, 38th, 39th and 46th SMW. On the other hand, natural enemies viz; spiders, lady bird beetles, lace wings, hover flies and ants were found predominantly during period of 34th to 36th SMW. A correlation studies shows that rainfall had a negative correlation with semilooper, whitefly, leafhopper, and hover fly and green lacewing population. Significantly positive correlation was observed between maximum temperature and mealy bug, green stink bug, pink bollworm and green lacewing, hover fly, white flies, and chafer beetle and spider population. Diversity of arthropod fauna was moderate to rich in Bt cotton agro-ecosystem of the selected study area (H'=2.09) with higher abundance of aphids followed by whiteflies, leaf hoppers, mites, thrips and red cotton bugs.