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期 刊 ：植物保护学报 2011年

关键词：甜菜；

Keywords:Alternaria augustiovoide, Echinochloa crus-galli, tenuazonic acid, lipoxygenases, lipid peroxidation,

摘 要 ：由甜菜尾孢菌Cercospora beticola引起的甜菜褐斑病(Cercospora leaf spot, CLS)是甜菜生产中危害较重的叶部真菌病害,导致甜菜产量和含糖量下降。由于CLS早期症状不易识别,传统病斑形态目测诊断法易错过最佳防治时期,因此分子检测方法对于CLS的准确监测十分重要。迄今为止,国外已报道的分子检测法主要有基于甜菜尾孢菌 rRNA-genes的actin gene编码区和ITS区结合限制性酶切的分子检测法、基于 rRNA-genes的ITS区结合测序的检测方法和基于大量尾孢属真菌RAPD多态性分析而设计的特异引物Cebe2检测法。目前,我国对甜菜尾孢菌的分子检测工作尚未见报道,为此,本试验对甜菜尾孢菌上述3种主要分子检测方法进行了比较,并进一步验证了特异引物Cebe2的可靠性,初步确立了我国甜菜尾孢菌的快速分子检测技术体系,为我国CLS的早期准确检测和有效控制提供技术支持。

Abstract:In order to know the action of tenuazonic acid (TeA) produced by Alternaria augustiovoide strain AAEC05-3 on Echinochloa crus-galli (L.), the effect of TeA on lipid peroxidation of E.crus-galli leaf was studied by leaf segment method in vitro. The result showed that low concentration TeA did not affect the membrane permeability and lipid peroxidation of E.crus-galli leaf, but the membrane permeability and lipid peroxidation increased significantly in 24 h after treatment with high concentration of TeA. When E.crus-galli leaves were treated with 100μmol/L TeA, the relative conductivity and malondialdehyde (MDA) content increased 28.21% and 63.58%, respectively. After the treatment of 100μmol/L TeA, lipoxygenases (Lox) activity of leaf increased 61.59%, meanwhile, the content of unsaturated fatty acids decreased dramatically. The content of linoleic acid and linolenic acid decrease 19.56% and 17.20% in 100μmol/L TeA treatment, respectively. After the treatment of 100μmol/L TeA, the fatty acid hydroperoxides (FAH) was largely accumulated in E.crus-galli leaf. The results indicated that TeA could induce the lipid peroxidation of E.crus-galli leave. It is deduced that the lipid peroxidation induced by TeA could be Lox-mediated lipid peroxidation.

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