苗期不同程度干旱胁迫和复水对藜麦生长和生理特性的影响

In order to clarify the effects of different degrees of drought stress and rehydration on the growth and physiological characteristics of quinoa at seedling stage, and provide important reference for the improvement of biological water-saving cultivation techniques and the research of drought-resistant biological breeding of quinoa. In this study, three drought stress levels were set, there were mild (LD), moderate (MD) and severe drought stress (SD). The soil relative water content accounted for about 55%, 35% and 15% of the field capacity, respectively, and compared with normal irrigation (CK, the soil relative water content accounted for about 75% of the field capacity). Each process was repeated 3 times. The indexes (plant biomass and physiological and biochemical indexes) were determined under stress for 24, 48 and 96 hours. After 96 hours of stress, all the plants were irrigated normally（treated again）, and after 1 day of treatment, the biomass and physiological and biochemical indexes continued to be determined. The results showed that mild and moderate drought stress could increase the root length of quinoa seedlings. Rehydration after 96 hours of drought, mild and moderate drought stress can make the plant height of quinoa seedlings elongate, and the fresh weight of roots and aboveground parts increase. With the increase of drought stress, the contents of proline and malondialdehyde in quinoa seedlings showed an upward trend, including soluble sugar, soluble protein content, SOD and POD.