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

Abstract

Transgenic tomato plants of south Indian cultivar A rka 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 transforma tion due to high regeneration efficiency, molecular analysis through PCR for puta tive transformants in T 0 generation and qualitative ELISA method was performed for Bt p rotein expression followed by insect bioassays. Insect bioassay studies was condu cted 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 dep loyed 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 T 1 lines is highly important to obtain single copy num ber plants since the expression of Bt protein in successive generations promotes effective management of this pest in the future. Keywords: Agrobacterium, Bt Cry2A, Helicoverpa armigera, Tran sformation.