对干旱-复水条件下酸枣幼苗相对含水量(RWC)、组织含水量、耗水量、保护酶(SOD、POD、CAT)活性、细胞膜相对透性,蒸腾速率(Tr)、光合速率(Pn)、气孔导度(Gs)进行测定,研究干旱-复水对酸枣幼苗的生理影响.试验设4个处理,分别是1次(Ⅰ)、2次(Ⅱ)和3次(Ⅲ)干旱-复水周期和对照(CK).结果表明:复水后,酸枣幼苗的RWC随时间推移呈先下降后稳定的变化趋势,且在复水后第3 d及以后RWC随干旱-复水次数的增加而升高;耗水量在复水当天达最高值,组织含水量在大量耗水后(复水次日)出现最低值;复水次日酸枣幼苗的保护酶随干旱-复水次数的增加而升高,而保护酶活性较低的处理细胞膜相对透性较高,表明细胞膜受伤害较严重;经1次干旱-复水处理的酸枣幼苗在复水当天的Tr、Pn、Gs均为最低.试验证明酸枣幼苗能在反复的干旱-复水中建立对干旱逆境的抵御,并且经多次干旱-复水处理的酸枣幼苗能在再一次复水后迅速恢复蒸腾和光合以减少干旱胁迫对自身的伤害.%Seedlings relative water content (RWC), tissue water content, water consumption rate, protective enzyme (SOD, POD and CAT) activity, relative membrane permeability, transpiration rate (Tr), photosynthetic rate (Pn) and stomatal conductance (Gs) were analyzed to study the effects of water stress and re-watering on wild jujube. Four treatments, including one circle ( Ⅰ ), two circles ( Ⅱ ) and three circles (Ⅲ) water stress/re-watering treatments, and a normal watering (CK) treatment were designed in the experiment. Based on the results, RWC initially decreased, and then stabilized after re-watering. Generally, RWC increased with increasing water stress/re-watering circle after the third day of re-watering. While water consumption rate was highest on the day of re-watering after water stress, tissue water content was lowest on the second day of re-watering. On the second day after re-watering,protective enzyme activities in wild jujube seedlings increased with increasing water stress/re-watering circle. Relative membrane permeability was higher under treatments with lower protective enzyme activity, indicating serious damage of seedling cell membranes. Wild jujube seedling Tr, Pn and Gs after one water stress/re-watering circle were lowest on the day of re-watering. The experiment further showed that wild jujube seedlings became drought resistant after several water stress/re-watering circles. After two or three water stress/re-watering circles, transpiration and photosynthesis in wild jujube seedlings were recovered and drought damage was decreased.
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