Strengths, weaknesses, opportunities and threats (SWOT) analysis of Bt cotton in India

The cotton ecosystem in India is different from rest of the world; it is the only country where seven cultivated types of cotton (four species + three types of hybrids) are commercially grown. The green signal for commercial cultivation of Bt-cotton has been a milestone where yield loss due to bollworms was considered as a social catastrophe. Release of Bt-cotton has been a declared war between three bollworms (H. armigera, Erias and Pectinophora) and Bt-cotton. Widespread trials of Bt-cotton have indicated possibility of reduction to the tune of 50% insecticide sprays indicating good bollworms. Helicoverpa armigera was knocked down by Bt-cotton till 100 days. ETL (1 larva) crossed two times more in NBT genotypes than Bt genotypes. The efficacy of Bt gene was evident because there was large gap between respective Bt and NBt types. The trials conducted in Karnataka have emphasized the need for increase in basic inbuilt tolerance to bollworms in the cotton genotypes subjected for transformation. It is because a conventional intra hirsutum hybrid DHH11(NBt) produced 27.62% increased yield than one of the Bt genotypes (MECH-162). Further, among the NBt types conventional check DHH-11 itself was superior than other genotypes. The SWOT analysis (Strength, Weaknesses, Opportunities and Threats) of Bt-cotton has been made in relation to Indian rainfed and irrigated. This analysis indicated different strategies, in development and spread of Bt-cotton in India. Transformation of G. arboreum and G. herbaceum cotton has been found to be most urgent to avoid further genetic erosion in the country. Genotypic independent transformation is crucial for Bt gene transfer in India because as many as 45 genotypes adapted to various agro-climatic zones are being cultivated on large scale in India under different agro-ecosystems. Efforts at Dharwad centre have revealed the possibility of transformation in diploids. Crop phenology in India has great diversity and has many alternate hosts to Helicoverpa armigera. Hence delay in resistance development in India is expected. Further, Indian laboratories are also working for transformation of multiple gene constructs to maintain genetic diversity for cry genes. Tailoring good cotton genotypes with Bt genes provide a way for exploitation of complete yield potential of the crop in the present millennium. This paper deliberates our experience in conducting Bt trials, superimposing data of Bt-cotton in Indian ecology and genetic transformation studies.