棉花多酚类、黄酮类含量与抗枯萎病关系的研究

Studies on the Content of Polyphenols and Flavones in Cotton Plant and Their Relationship to Fusarium—wiit Resistance

本研究测定了抗、感枯萎病棉花品种多酚类及黄酮类物质的含量,分析了其与抗病性的关系。结果表明,无病条件下,3叶期感病品种的多酚类含量明显高于抗病品种。而黄酮类的含量则相反。在种子接菌条件下,抗病品种86—1多酚类含量急剧上升,至花蕾期含量达1叶期的2.7倍;感病品种鲁棉1号的含量则迅速下降,表明多酚类物质的大量形成是抗病的应激代谢反应。在接菌条件下感病品种黄酮类含量1～3叶期上升,以后逐渐下降;而抗病品种1叶期含量高,以后迅速下降至5叶期达最低,其后又上升,形成V形低谷,说明大量黄酮类物质降解可能与植保素形成有关。上述两类物质的动态变化与抗病性的表达具有重要作用。

Analysis of polyphenols and flavones—content in Fusarium—wilt resistant or susceptible cotton cultivars was made in an attempt to find their relationship to the cultivars with wilt resistance performance. In disease free condition, mesurements obtained from 3leaf—old plants showed that polyphenols—content in susceptible cultivars was noticeably hig her than that in resistant ones while the content of flavones was in a reverse order. When seeds contaminated with the wilt pathogen after planting were examined, during the period from 1—leaf stage to flower—budding stage, the content of polyphenals in resistant cultivar '86—1' increased rapidly that was 2. 7 times at flower—budding stage as much as what at 1—leaf stage while in susceptible cultivas 'Lu—mian 1', polyphenols—content showed a quick decline in the same period. These findings suggest that polyphenols in large amount are formed by stress—metabolic reaction. In comparison with polyphenols, the content of flavones displayed a different feature. In susceptible cultivar 'Lu—mian 1', though it increased at 1—to—3—leaf stage, declined gradually afterwards. In the resistant cultivar '86—1', after the highest flavones—content was found at 1—leaf stage, it dropped quickly until the lowest level appeared at 5—leaf stage, and then increased again, giving a V—shaped truck. The legradation of flavones in large amount may be correlated with the formation of phytoalexin. The dynamic changes in content of these two substances may be an important indicator accounting for cotton's wilt—resistance expression.