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期 刊 ：植物保护学报 2011年

关键词：狭卵链格孢；稗草；细交链孢菌酮酸；脂氧合酶；脂质过氧化；

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

摘 要 ：为明确狭卵链格孢菌Alternaria augustiovoide菌株AAEC05-3产生的毒素细交链孢菌酮酸(tenuazonic acid,TeA)的作用机制,利用离体试验,研究了TeA对稗草叶片细胞膜脂质过氧化的影响。结果显示,低浓度TeA处理对稗草叶片的细胞膜透性和脂质过氧化影响不大;用高浓度TeA处理稗草叶片24 h后,稗草叶片细胞膜透性和脂质过氧化作用显著增强。TeA浓度为100 μmol/L时,稗草叶片相对电导率和丙二醛(MDA)含量分别增加28.21%和63.58%;脂氧合酶(Lox)活性增高61.59%,且不饱和脂肪酸含量显著降低,亚油酸(18∶2)和亚麻酸(18∶3)分别降低19.56%和17.20%,脂肪酸氢过氧化物在叶片中大量积累。表明TeA可以诱导稗草叶片细胞膜的脂质过氧化作用。

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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