Overexpression of the Glyoxalase II Gene Leads to Enhanced Salinity Tolerance in Brassica Juncea

Engineering of salinity tolerance in agronomically important crop plants is required to increase their productivity by enabling them to grow in saline soils, which are otherwise left uncultivated. Since an increase in the enzymes of glyoxalase system has been shown to impart salinity tolerance in the model plant tobacco, we used the glyoxalase II gene for engineering salinity tolerance in an important oil yielding crop, Brassica juncea. The transgenic plants of B. juncea overexpressing the glyoxalase II gene showed higher salinity tolerance as compared to the untransformed control plants as observed by delayed senescence in leaf discs at 400 mM and 800 mM NaCl in T1 generation. The percentage of germination of the T2 transgenic seeds was higher at 150 mM and 200 mM NaCl as compared to the seeds of untransformed plants. This for the first time demonstrates the applicability of utilizing the glyoxalase II gene for enhanced salinity tolerance in an oilseed crop plant B. juncea.

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