酸枣保护酶活性和膜脂过氧化产物对干旱胁迫的响应

以3年生酸枣为试材,通过盆栽控水试验法研究干旱胁迫条件下酸枣生理生化特性的响应规律。结果表明:随着干旱胁迫梯度的加大、干旱时间的延长,保护酶SOD、POD和CAT在酸枣体内积累,表现出先增后降的变化趋势;在中度干旱下SOD活性达到608.36 U/g·FW,高于CK组52.14%且差异极显著(P0.01),POD活性达到190.97μg/min·g·FW,高于CK组113.59%(P0.01)。而CAT活性变化与SOD、POD略有不同,随胁迫程度的加重,其活性逐渐降低,仅高于CK组1.40倍(P0.05)。电导率、NR活性以及丙二醛(MDA)含量表现出增加的趋势;电导率持续升高,高于CK组11.14倍(P0.01),对膜的结构和功能破坏越严重。NR活性达到14.60μg/(g·h)比CK增加了94.66%(P0.01),MDA含量达到26.82μmoL/g·FW,是CK组的2.71倍(P0.05),膜脂过氧化反应加强,对膜的伤害增加。

The Activities of Protective Enzymes and Product of Membrane Lipid Peroxidation of Zizyphus jujuba Mill.Responsed to Drought Stress

The method of potting water control was used to study the law of the physio-bioehemical char- acteristics of Zizyphus jujuba Mill. of three-years-old growth responded to drought stress. The results showed that the content of protective enzymes SOD, POD and CAT were accumulated under drought stress gradient increase and time prolong, the variation trend was increased early and decreased later. SOD ac- tivity reached 608.36 U/g· FW, 52.14% higher than the CK group under moderate treatment and the difference significantly （P 〈 0. 01 ）. POD activity reached 190.97 p,g/min, gFW, higher than 113.59% of the CK group （P 〈 0.01 ）. The change of CAT activity has slightly difference from SOD and POD, which decreases gradually with stress severity, only 1.40 times higher than the CK group （ P 〈 0.05 ）. Conduc- tivity, NR activity and the content of malondialdehyde （MDA） were rising continuously. Conductivity continues to rise, than group CK 11.14 times （P 〈0.01 ）, and more serious damage to the structure and function of the membrane. NR activity reached 14.60 μg/（ g.h）, which is an increase of 94.66% com- pared with CK （P 〈0.01 ）. The content of MDA reached 26.82 umoL/g. FW, which is CK 2.71 times （P 〈 0. 05 ）. Membrane lipid peroxidation strengthening is harmful to the film.