Effects of Exogenous Melatonin on wheat quality under drought stress and rehydration

Melatonin (MT) regulates and enhances crop tolerance to drought stress. However, the effect of melatonin spraying on grain quality under drought-rehydration treatment is evaluated insufficiently currently. Here, the present study is conducted by spraying 100mM MT before wheat grain-filling and then drought-rehydration treatment is carried out. Rewatering after drought stress increased appreciably wet gluten content, sedimentation index, total protein content, and glutein content of wheat grains and decreased prolainm content, albumin content, and globulin content. And MT application effectively alleviated grain quality damage, reducing wet gluten content and glutein content. Besides, MT compensated for the oxidative damage and the membrane lipid peroxidation damage caused by drought-rehydration treatment. In addition, two drought stresses reduced significantly photosynthetic parameters. And MT effectively improved the photosynthetic efficiency. These results indicated that MT was feasible to enhance wheat resistance and ameliorate grain quality during drought and rehydration.