Mehmet Cengiz BALOĞLU, Ayşe Meral YÜCEL, Hüseyin Avni ÖRTEM, Musa KAVAS

Enhanced salt tolerance of transgenic tobacco expressing a wheat salt tolerance gene

Soil salinity is one of the most important limiting factors of agricultural productivity in the world. The Triticum aestivum salt tolerance-related gene (TaSTRG) possesses a functional response to salt and drought stress conditions. A variety of stress factors, such as salt, drought, abscisic acid, and cold, may induce the expression of TaSTRG in wheat. In this study, the TaSTRG gene was transferred to tobacco via Agrobacterium-mediated transformation. Overexpression of TaSTRG in transgenic tobacco plants indicated higher salt tolerance and mediated more vigorous growth than in wild-type plants. Under salt stress conditions, the transgenic tobacco plants had higher germination and survival rates and longer root length than the control plants. Under salt treatments (200-250 mM), TaSTRG-overexpressing tobacco plants accumulated a higher amount of proline and had significantly lower malondialdehyde content than wild-type plants. Furthermore, transgene inheritance followed Mendelian laws, indicating the stability of TaSTRG in transgenic tobacco plants. These results indicated that the wheat TaSTRG gene plays an important role in responding to salt stress.

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