西瓜雄性不育系‘Se18’抗氧化酶活性和内源激素含量变化分析

Analysis of the Changes in Antioxidant Enzymes Activities and Endogenous Hormones Contents in Watermelon Male Sterile Line Se18 During Bud Development

以西瓜雄性不育系‘Se18’为试材,研究开花期间花蕾和叶片中抗氧化酶活性和内源激素含量的变化。结果表明:不育株雄花花蕾在整个发育时期,超氧化物歧化酶(SOD)和过氧化物酶(POD)活性升高,过氧化氢酶(CAT)活性降低;可育株中CAT活性升高,SOD和POD活性降低。不育株和可育株雄花花蕾中的生长素(IAA)、脱落酸(ABA)、赤霉素(GA_3)、玉米素核苷(ZR)、茉莉酸(JA)和油菜素内酯(BR)及异戊烯基腺嘌呤核苷(IPA)等7种内源激素含量变化趋势不同,且含量差异明显。其中,不育株中IAA、GA_3、BR和IPA含量降低,JA含量升高;可育株中JA、BR、GA_3和IPA含量降低,IAA和ZR含量升高。不育株叶片中的IAA、ZR和BR含量显著下降,ABA和JA含量显著上升;IAA/ABA、IAA/GA_3、IAA/JA、IAA/ZR、IAA/BR、IAA/IPA及ABA/GA_3、ABA/ZR在不育株和可育株间的变化趋势不一致,且差异较大。因此推测上述抗氧化酶活性变化和内源激素含量异常可能与西瓜雄性不育的发生密切相关。

Watermelon male sterile line Sel8 was used as the testing material, changes in antioxidant enzymes activities and endogenous hormones contents in the lamina and flower bud of this line were studied. The results showed that the activities of SOD and POD in sterile watermelon plants were markedly increased, while the activity of CAT was declined. However, the activity of CAT in fertile watermelon plants was markedly increased, while the activities of SOD and POD were declined. Moreover, the contents oflAA, ABA, GA3, ZR, JA, BR and IPA exhibited different variation trends between sterile and fertile plants throughout the whole male flow buds development stage, and the difference in contents between them was also significant at each stage. The declining oflAA, GA3, BR and IPA contents and rising of JA content might be closely connected with the occurrence of watermelon male sterility. But the declining of JA, BR, GA3 and IPA contents and rising of IAA and ZR contents in fertile watermelon plants. Significant declining of IAA, ZR and BR and distinctive rising of ABA and JA contents in the lamina of sterile plants were observed. Inconsistent variation trend was found in terms of IAA/ABA, IAA/GA3, IAA/JA, IAA/ZR, IAA/BR, IAA/IPA, ABA/GA3 and ABA/ZRbetweenthe male sterile and fertile plants and the difference was great. Therefore, we speculated that the changes in antioxidative enzymes activities and abnormal endogenous hormones levels might be responsible for the occurrence of male sterility in watermelon.