ABSTRACT
This review summarizes the research progress of the adaptive mechanism of oat (Avena sativa) to drought stress. The adaptation of oat to drought stress is related to various factors, including receiving abscisic acid (ABA) signals to actively close stomata, reducing photosynthetic efficiency, decreasing growth and accelerating senescence, and reducing nutrient consumption; regulating the expression of related genes through phytohormones, and transmitting drought stress signals; upregulating the expression level of antioxidant enzyme genes, increasing the activities of antioxidant enzymes, and alleviating or avoiding oxidative damage to cell membranes by scavenging or regulating reactive oxygen species (ROS). Oat may regulate cell osmotic pressure in a low-cost and convenient way through inorganic ions in the early stage of drought stress. Organic compatible solutes are synthesized and regulate cell osmotic pressure to relay the osmotic regulation of inorganic ions at the initial stage of drought stress and together with inorganic ions to regulate cell osmotic pressure. At the molecular level, oat genomics research has made important progress, and some drought tolerance-related genes and some transcription factors (TFs) have been studied and identified. Exogenous growth regulators such as proline, melatonin, salicylic acid and potassium can improve the ability of oat to withstand drought stress. Oat can survive in arid and semi-arid environments, suggesting that there is a unique drought tolerance mechanism.
