ORIGINAL ARTICLE

Effect of Exogenous Trehalose on Physiological Responses of Wheat Plants Under Drought Stress 

Drought stress causes physiological changes in plant morphological growth and development. The protective role of trehalose (Tre) was investigated through exogenously applied to seedlings of wheat cv. Sakha 93 plants. Pots experiment were divided into four groups: control, Tre treatment, drought stress and drought stress with Tre treatment. Samples were collected in two stages after 7 and 14 days from drought stress to determine the fresh weight, dry weight, chlorophyll pigments, relative water content, electrolytic leakage, proline, malondialdehyde, antioxidant enzyme activities, and carbohydrates content. Drought stress reduced many growth and physiological characters. It significantly increased specific activities of guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) and significantly decreased the catalase (CAT) activity. It caused significantly increased in the Tre content while reduced sucrose and starch contents. Combination exogenous applied Tre (40 mM) with drought stress improved some growth parameters and photosynthetic pigments. Application of Tre markedly decreased proline and malondialdehyde contents, GPX; APX activities whereas increased CAT activity. Tre treatment appeared increased in the internal Tre content, on the other hand; exogenous Tre maintained the sucrose and starch contents in the seedlings of wheat plants under drought stress. The results concluded that applied Tre alleviated the adverse effect of drought stress on wheat plants by enhancing the antioxidant defense system and conservation of the membrane stability.