Expression of nhaA gene confers salt-sensitivity in transgenic rice cultures and plants

Salinity is an important abiotic factor that limits crop productivity for which solutions are being investigated through extensive research in plant biotechnology. The current study was designed to determine if expression of Escherichia coli nhaA gene, a Na+/H+ antiporter, can confer salt tolerance in transgenic rice cultures and plants. Transgenic rice calli and plants containing the nhaA gene were treated with various concentrations of NaCl. Lower biomass and higher death rates were observed under salt stress conditions for these transgenic materials. These data suggest that transgenic rice containing the nhaA gene driven by the maize ubiquitin promoter are salt sensitive. In contrast to previous reports, an enhanced salt tolerance after nhaA expression in rice cultures and plants is not demonstrated in our current study.