Abstract:A pot experiment was performed in a rain shelter. The aim of this study was to explore the possible physiological responses or roles of pre-drought priming to/in damage alleviation of subsequent severe drought stress in peanut seedlings. Three treatments were designed as follows:control (75% of field water capacity), drought stress without pre-drought treatment (D, 35%), and subsequent drought stress with pre-drought treatment (DD, 35%). Compared with the D treatment, pre-drought priming increased the leaf relative water content and reduced proline accumulation in the DD treatment when seedlings experienced subsequent drought stress. In addition, MDA and O·-2 contents and activities of antioxidant enzymes including superoxide dismutease (SOD), catalase (CAT), and peroxidase (POD) decreased in response to the DD treatment and recovered to the level of the control, or lower, following rewatering. Drought decreased photosynthetic rate (PN), photosynthetic capacity (PC), and maximum quantum yield of PSⅡ (YQ). However, PN, PC, and YQ in the DD treatment were higher than those in the D treatment when seedlings experienced a second drought stress. The hysteresis area and hysteresis rate of leaf photosynthesis (HP) and stomatal conductance (Hg) decreased significantly in response to the DD treatment following repetitive drought and rewatering. In conclusion, pre-drought priming increased leaf relative water content during the subsequent drought stress, reduced physiological damage caused by subsequent drought stress, and enhanced resistance to drought stress. The seedlings that experienced drought priming had the capacity to recover quickly to the growth level observed under normal soil water conditions. Therefore, peanut seedlings can adapt or ‘recognize’ the initial stressor from a previous exposure to drought stress, and displayed a more rapid and stronger physiological defense to the second drought stress using a fast physiological recovery mechanism.