Effect of Bt cotton litter and squares on soil collembolan, formicid, and non-acarine mesofauna abundance.

Abstract This experiment examined the impact of four BGII Bt cotton varieties (Mahadev BGII, MRC-6918 BGII, MRC-7351 BGII, and Sumo BGII) and one non-Bt variety (Suraj) on soil mesofauna, focusing on collembola, ants, and non-acarine mesofauna in an undisturbed natural grassland. Soil and litter mesofauna showed variable preferences among the different Bt cotton varieties. Specifically, average soil mesofauna abundance per 100 grams was lowest in Sumo Bt squares (299.33) and highest in MRC-7351 Bt litter (4948.67). Entomobryid collembola populations per 100 grams ranged from 0.00, observed in Sumo Bt squares and silver oak leaves, to a maximum of 40.00 in Suraj non-Bt squares. Podurid collembolans were observed only in the Mahadev litter (4.33 per 100 grams). Ant abundance per 100 grams was lowest in Sumo Bt squares (1.33) and highest in MRC-6918 squares (23.67). Non-acarine soil mesofauna per 100 grams were most abundant in Sumo Bt squares (293.67) and least abundant in MRC-6918 squares (1.00). Key words:Ants, BG II Bt cotton, Entomobryidae, Litter and soil mesofauna, Poduridae References Blackwood, C.B. and Buyer, J.S., 2004.Soil microbial communities associated with Bt and Non- Bt corn in three soil. J. Environ. Quality,33:832-836. Dunsfield, K.E. and Germida, J.J., 2004.Impact of genetically modified crops on soil and plant associated microbial communities. J. Environ. Quality, 33: 806-815. Griffith, B.S., Caul, S., Thompson, J., Birch, A.N.E., Scrimgeour, C., Cortet, J., Foggo, A., Hackett. and Krogh, P.H., 2006.Soil microbial and faunal community responses to Bt maize and insecticide in two soils. Env. Quality, 35: 734-741. Gupta, V.V.S.R. and Stephanie Watson, 2004. Ecological impacts of GM cotton on soil biodiversity. Consultancy report by CSIRO Land and Water, Australia. Kumar, N.G., Nirmala, P., Avinash, T.G. and Saleem Sakhidad, 2025a. Abundance of soil mesofauna in the soil and litter associated with Bt cotton compared to non-Bt crops. J. Soil Biol. Ecol.,45(1); 68-73. (doi.org:10.58682/JSBE.45.1/NPJL8340). Kumar, N.G., Nirmala, P., Avinash, T.G. and Saleem Sakhidad, 2025b. The influence of Bt cotton varieties litter and squares on the abundance of soil mesofauna and acarids. J. Soil Biol. Ecol.,45(2); 58-64.(doi.org:10.58682/JSBE.45.2/SWPC8823). Motavalli, P.P., Kremer, R.J., Fang, M. and Means, N.E., 2004. Impact of genetically modified crops and their management on soil microbiologically mediated plant nutrient transportations. J. Env. Quality. 33:816-824. O’Callaghan, M., Glare, T.R., Burges, E.P.J. and Malone, L.A., 2005. Effects of plants genetically modified for insect resistance on non-target organisms. Ann. Rev. Entomol., 50:271-292. Rui, Y.K., Yi, G.X., Zao, J., Wang, B.M., Li, H., Zhai, Z.X., He, Z.P. and Li, Q.X., 2005.Changes of Bt toxin in the rhizosphere of transgenic Bt cotton and its influence on soil functional bacteria. World J. Micro. Biotech., 21: 1279-1284. Stotzky, G., 2004.Peristence and biological activity in the soil of the insecticidal proteins from Bacillus thuringiensis especially from transgenic plants. Plant Soil. 266: 77-89. Sundararaj, N., Nagaraj, S., Venkataramu, M.N. and Jagannath, M.K., 1972. Design and analysis of field experiments. UAS, Misc. Series, No. 22, Bangalore. Tarafdar, J.C., Indira Rathore and Vandana Siva, 2012. Effect of Bt-transgenic cotton on soil biological health. Appl. Biol. Res., 14(1): 1-9. Wei, X.D., Zou, H.L., Chu, L.M., Liao, B., Ye, C.M. and Lan, C.Y., 2006. Field released transgenic papaya affects microbial communities and enzyme communities and enzymes activities in soil. Plant Soil. 285: 347-358. Xingyuan Men, Feng Ge, Xiangui Liu and Fedal N. Yardim, 2003. Diversity of arthropod communities in transgenic Bt cotton and non- transgenic cotton agroecosystems. Environ. Entomol. 32(2); 270-275.