Genetic Transformation of Tomato Using Bt Cry2A Gene and Characterization in Indian Cultivar Arka Vikas

Transgenic tomato plants of south Indian cultivar Arka Vikas were developed using Agrobacterium strain EHA 105, harbouring Bt Cry2A gene with a construct containing 35S CaMV promoter, OCS terminator and nptII selectable marker, through Agrobacterium-mediated transformation. This study was conducted to improve the regeneration and transformation protocol for south Indian cultivar Arka Vikas. Hypocotyl was used as explant source for transformation due to high regeneration efficiency, molecular analysis through PCR for putative transformants in T0 generation and qualitative ELISA method was performed for Bt protein expression followed by insect bioassays. Insect bioassay studies was conducted using neonate larva of helicoverpa armigera to screen the plants and the plants expressing good resistance with molecular and phenotypic characters were carried further for successive generations. The experimental results concluded that Bt gene was deployed in tomato cultivar successfully and had developed resistance to neonate larva of Helicoverpa armigera at laboratory conditions. These results signified that transgenic lines expressed substantial quantity of Bt Cry2A protein efficient in management of Helicoverpa armigera. Precise screening of transgenic T1 lines is highly important to obtain single copy number plants since the expression of Bt protein in successive generations promotes effective management of this pest in the future.