Abstract

Jatropha curcas’sdehydrin (JC-DHNS) has been previously shown to play a role during natural dehydration process associated with maturation of Jatropha curcasseed. In this study, we generated transformed rice plant (tp) over expressing JC-DHNSgene and examined the role of over expressed gene in improving the drought tolerance. The tp plants showed a stronger growth under water stress condition induced by addition 20% of PEG 6000. It also showed an enhanced water stress tolerance as indicated by growth parameters included, fresh and dry weight, chlorophyll content, maximum quantum yield, actual quantum yield of photosystem II and non-photochemical quenching. Also, tp plants showed higher membrane stability under drought comparing with non-transformed plant (wt) as indicated through determination of membrane electrolyte leakage, the values of malondialdehyde and, hydrogen peroxide content as indicator for oxidation level. The tp plant had higher content of osmoregulators substances such as proline, free amino acids and total soluble sugar. The tp plant showed higher content of enzyme activity such as and superoxide dismutase catalase and ascorbate peroxidase compared with wt. Our results clearly showed that tp rice plant with JC-DHNS better coped with drought stress due increasing photosynthetic efficiency and antioxidant enzymes activity.

Keywords: Dehydrine; Over expression; Rice; Drought tolerance