Agrobacterium-mediated transformation of chickpea with alpha-amylase inhibitor gene for insect resistance.

Chickpea is the world's third most important pulse crop and India produces 75% of the world's supply. Chickpea seeds are attacked by Callosobruchus maculatus and C. chinensis which cause extensive damage. The alpha-amylase inhibitor gene isolated from Phaseolus vulgaris seeds was introduced into chickpea cultivar K850 through Agrobacterium-mediated transformation. A total of 288 kanamycin resistant plants were regenerated. Only 0.3% of these were true transformants. Polymerase chain reaction (PCR) analysis and Southern hybridization confirmed the presence of 4.9 kb alpha-amylase inhibitor gene in the transformed plants. Western blot confirmed the presence of alpha-amylase inhibitor protein. The results of bioassay study revealed a significant reduction in the survival rate of bruchid weevil C. maculatus reared on transgenic chickpea seeds. All the transgenic plants exhibited a segregation ratio of 3:1.