Enhanced Drought Tolerance and Yield in Cry1ac and APX Co-Transformed Transgenic Rice (Oryza Sativa L.)

Abstract

In the present study, transgenic cry1Ac-APX plants were developed in popular rice variety, BPT 5204, employing Agrobacterium LBA4404 harbouring pcam-cry1Ac-APX vector. The transgenic plants generated were analysed based on herbicide (Basta) toleranceand molecular analyses. Seeds of T1 generation when germinated on MS medium containing 4 mg/l phosphinothricin (ppt) revealed 3 tolerant: 1 susceptible plants suggesting that the trangenes showed monogenic segregation. Homozygous lines were identified by 100% germination of T3 seed on PPT containing media. Abiotic stress assays of analysis cry1Ac-APX transgenic lines showed enhanced chlorophyll, proline and reducing sugars compared to untransformed control plants. The antioxidant enzymes SOD and CAT showed significantly higher levels in transgenic lines than UC.RT- PCR analyses revelled increased expression levels of drought related genes OsDREB, OsMYB and bZIP under both stressed and without stress conditions. Further, the pcam-cry1Ac-APX lines exhibited enhanced biomass and yield than UC.