Salt tolerance of potato genetically engineered with the Atriplex canescens BADH gene

Abstract

Potato (Solanum tuberosum L.) is among the top staple foods in the world, and salinity adversely affects its yield and quality. To improve salt tolerance in potato, the present study is focused on the Agrobacterium-mediated transformation of potato by the Atriplex canescens betaine aldehyde dehydrogenase (BADH) gene driven by single, double, and triple CaMV 35S promoters. The study led first to the detection of seven lines containing the BADH gene followed by the identification of T-DNA insertions via DNA hybridization and enzyme-linked immunosorbent assays. The salt tolerance was found to be promoter dependent, as the lines with triple promoters showed a higher resistance than those tranformed with single and double promoters. The transgenic lines showed lower content of H2O2 and malondialdehyde and a lower relative electrical conductivity than wild-type plants. Furthermore, these lines also showed higher proline and chlorophyll content. In silico analysis confirmed that the A. canescens BADH protein had a remarkable tendency to interact with sodium ions and water molecules like other BADH proteins. Taken together, the overexpression of BADH under triple CaMV 35S promoters enhanced salt tolerance of potato.