Overexpression of tobacco osmotin gene leads to salt stress tolerance in strawberry (Fragaria × ananassa Duch.) plants

Abstract

Transgenic plants of strawberry tolerant to salt stress were produced using Agrobacterium mediated gene transfer technology. Leaf discs of in vitro grown plantlets of strawberry cv. Chandler were used as explants. Agrobacterium tumefaciens strain GV2260 harbouring osmotin gene under the control of CaMV 35S promoter in a binary vector system pBinAR was used in transformation experiments. Transgene integration and copy number were assessed by PCR and Southern hybridization confirming single copy as well as multiple copies of transgene integration in 10 different lines of transgenic strawberry. Expression of osmotin gene was confirmed in transgenic lines TL3, TL5, TL9 using Northern hybridization, while biochemical analysis revealed enhanced levels of proline, total soluble protein and chlorophyll content as compared to the wild plants. Leaf disc assays performed using both wild-type and transgenic plants had shown that these transgenic lines were tolerant to salt stress.