万寿菊精油杀菌素对西瓜枯萎病菌的抑菌作用及对西瓜幼苗的影响

Studies on Antifungal Activity of Marigold Essential Oil Fungicide Against Fusarium oxysporum f.sp.niveum

采用田间试验和生物测定方法,研究了人工合成的万寿菊精油杀菌素对西瓜枯萎病菌和西瓜幼苗生长的影响。结果表明:0.5μg/mL万寿菊精油杀菌素24、48、72、144 h的抑制率分别为100%、76.7%、59.9%、56.8%;当浓度大于1.5μg/mL时抑制率达100%;10μg/mL万寿菊精油杀菌素处理西瓜幼苗的致萎指数得到显著降低,差异达显著水平(P<0.05);20μg/mL万寿菊精油杀菌素处理的西瓜枯萎病菌,大分子量的蛋白含量增多,小分子量的蛋白含量减少,但过氧化物酶的条带数没有变化;50μg/mL万寿菊精油杀菌素处理的西瓜苗叶片中3d后MDA含量减少差异显著(P<0.05),4d后过氧化物酶活性逐渐升高差异达显著水平(P<0.05),5d后差异极显著(P<0.01)。含药培养基上生长的西瓜枯萎病菌的果胶酶活性降低,呼吸强度明显提高,细胞膜通透性增大,几丁质酶活性稍高于对照。此杀菌素可用以预防和控制西瓜枯萎病,为西瓜枯萎病的综合防治提供一种新的方法和途径。

Marigold essential oil fungicide,synthesized analogues of extracts of Tagetes patula L.root,against Fusarium oxysporum f.sp.niveum(FON) and their influence on watermelon plant were studied by the methods of field test and biology assay.The results showed that the inhibition rate of 0.5μg/mL marigold essential oil fungicide after 24,48,72,144 h was separately 100%,76.7%,59.9%,56.8%,and the inhibition rate was 100%over 1.5μg/mL;wilting index was a significant difference with 10μg/mL reagents(P<0.05);protein of higher molecular weight enhanced and lower molecular weight reduced with 20μg/mL reagents,but the POD isozyme was not changed;with 50μg/mL reagents MDA contentreduced after 3 d to a significant difference(P<0.05),POD activities enhance after 4 d to a significant difference(P<0.05) and after 5 d to a higher difference(P<0.01).At the same time pectinas activities degraded,respiratory intensity enhanced,membrane permeability magnified and chitinase activity slightly raised of FON The fungicide could be used for preventing and controlling FON,which would provide a new method and technique for the integrated control of FON.