Abiotic stress is limiting to tea productivity. The severity and duration of the abiotic stress are critical, as it has multifarious effects on crop plants. The tea plant is commonly grown in rain-fed ecosystems and thus it encounters seasonal water deficit conditions that induce loss in crop yield. In this review, we have highlighted the effects of abiotic stress (drought, metal etc.) on the growth, mineral nutrition, reactive oxygen species (ROS), and antioxidant metabolism in tea plants. This article also highlights the mechanism of drought stress amelioration in tea plants on a physiological and biochemical basis. Drought stress caused increased water loss rate (WLR) and decrease in relative water content (RWC), dry mass, chlorophyll, carotenoid, and total phenolic contents of leaf and antioxidants like ascorbate and glutathione in tea. Leaf antioxidant enzymes (e.g., SOD, CAT, GR, etc.) showed differential activities whereas there was increase in ROS and lipid peroxidation with decreased POX activities with progressive stress. Drought stress altered antioxidative response with apparent decrease in mineral nutrient (Zn, Ca, Na, Fe, Mg, and K) contents of leaves suggesting that mineral deficiency mediated drought stress induced oxidative damage in tea. Tea plants exposed to heavy metals (e.g., Cd, Cu, Al) also showed reduction in growth and antioxidative responses. Further, a post-drought recovery study in tea also reveals that drought induced biochemical damages are not permanent, as the plant recovers on rehydration. Mineral nutrients play an important role in post-drought recovery in tea. The process of recovery was significantly influenced by foliar spray of K, Ca, Zn etc., leading to improved antioxidant potential. Thus, drought tolerance and post-drought recovery can be improved by application of nutrients like K, Ca, Zn, B etc. However, molecular mechanisms of abiotic stress amelioration and post stress recovery mediated by these nutrients need to be explored in future.
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