冠菌素对玉米幼苗耐干旱胁迫的诱导效应  

Induced Drought Resistance of Maize(Zea may L.) Seedling by Coronatine

作　　者：汪宝卿[1] 李召虎[1] 段留生[1] 翟志席[1] 

机构地区：[1]中国农业大学作物化学控制研究中心,北京100094

出　　处：《西北植物学报》2007年第4期740-746,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家高技术研究发展计划(863计划)项目(2003AA241170)

摘　　要：以玉米幼苗为材料,在20%PEG模拟干旱条件下,研究了植物生长物质冠菌素0.001～1.0μmol·L^-1处理时叶片水分状况及其脯氨酸、可溶性糖、MDA含量及抗氧化酶活性.实验表明,在干旱胁迫条件下,低浓度（0.01μmol·L^-1）的冠菌素处理能显著降低干旱胁迫下叶片水势,并显著提高玉米幼苗叶片相对含水量、可溶性糖和游离脯氨酸的含量;同时能显著提高玉米叶片中POD、CAT和APX的活性（分别比对照高32.1%、13.8%和29.5%）,而对SOD和GR的活性无显著影响;此时叶片中MDA的含量显著比对照降低11.6%,能够在一定程度上维持细胞膜的完整性.高浓度冠菌素处理（1.0μmol·L^-1）下各指标的变化趋势则相反.结果证明,低浓度冠菌素（0.01μmol·L^-1）能增强玉米幼苗耐干旱胁迫的能力.Maize seedling with 20%PEG simulating drought stress were used to research the effects of leaf water status,proline, soluble sugar, MDA and antioxidant enzymes activity after 0. 001 - 1.0 μmol·L^-1 plant growth regulator coronatine application. The results showed that low concentration coronatine can significantly improved leaf relative water content, decreased leaf water potential,increased soluble sugar and unconjugated proline concentration under drought stress. At the same time, 0.01 μmol·L^-1 coronatine can enhance the activity of POD, CAT and APX by 32. 1%, 13.8% and 29.5 % respectively, compared to control,but has little effect on activity of SOD and GR. It also significantly decreased MDA content by 11.6% compared to control. Therefore, the integrity of cell membrane was maintained in some extent, However,the results with high concentration coronatine （1.0 μmol·L^-1） treatment were reversed to low concentration coronatine （0.01 μmol·L^-1） treatment. It proved low concentration coronatine （0.01 μmol·L^-1） can improve the capacity of the drought resistance of maize seedling.

关 键 词：冠菌素 玉米幼苗 干旱胁迫 抗氧化酶 

分 类 号：Q945.78[生物学—植物学]