Impact of zinc on dehydration and rehydration responses in tea.

Zinc nutrition of tea (Camelia sinensis) have a great impact on acclimation to dehydration stress and on improvement of stress recovery. Dehydration stress induced by withholding water for 7 d decreased relative water content, dry mass of leaf, and content of antioxidants like ascorbate and glutathione and increased H2O2 content and lipid peroxidation and changed activities of superoxide dismutase, catalase, peroxidase, and glutathione reductase. A pre-treatment with 0.1 and 0.5 mM ZnSO4 minimized these effects and increased Zn uptake. Further, foliar spray with 0.1 and 0.5 mM ZnSO4 before rehydration lowered H2O2 generation, increased content of antioxidants and activities of antioxidative enzymes, and decreased lipid peroxidation. The present findings suggest that zinc regulates water stress responses and recovery after rehydration in tea. [ABSTRACT FROM AUTHOR]