In order to understand the compsition and structure of herbicidal component of Pythium aphanidermatum,the isolation and structural indentification were researched.The culture filtrate was extracted by ethyl acetate,pe...In order to understand the compsition and structure of herbicidal component of Pythium aphanidermatum,the isolation and structural indentification were researched.The culture filtrate was extracted by ethyl acetate,petroleum,and chloroform with the same volume respectively and the activity of the crude toxin was bioassayed.The toxin was separated by using the method of thin layer chromatography（TLC）,then the main fraction was separated by HPLC,and the structure was analyzed by the sepctrum of IR,13C-NMR and 1HNMR.The results showed that the ethyl acetate extracts had the strongest herbicidal activity.Using the method of TLC,the bioassay results showed that the extracts with Rf 0.19 had the strongest effect on weeds and the inhibition to Digitaria sanguinalis and Amaranthus retroflexus reached five levels,and the component was proved to be dimethyl o-phthalate from the spectrum of IR,13C-NMR and 1HNMR,which was one of the components from the toxin,and it had herbicidal activity.展开更多
小麦赤霉病(Fusarium head blight,FHB)是由禾谷镰刀菌(Fusarium graminearum)引起的重要病害,不仅造成了严重产量损失,其产生的真菌毒素更威胁了粮食安全。该病害具有“可防不可治”的特点,目前主要依赖化学防治,但长期使用化学药剂易...小麦赤霉病(Fusarium head blight,FHB)是由禾谷镰刀菌(Fusarium graminearum)引起的重要病害,不仅造成了严重产量损失,其产生的真菌毒素更威胁了粮食安全。该病害具有“可防不可治”的特点,目前主要依赖化学防治,但长期使用化学药剂易导致病原菌抗药性和环境污染。为开发绿色防控方法,本研究从小麦根际土壤中筛选获得13种生防菌,其中第12号菌株[鉴定为瓜果腐霉(Pythium aphanidermatum)]表现出显著抑菌效果。结果显示,该菌株在平板对峙实验中,使病原菌菌落直径减少69.2%(1.47 mm vs.对照组4.78 mm),抑制率达77%(P<0.01)。显微观察发现病原菌菌丝出现明显畸变,表明存在溶菌作用。胚芽鞘实验进一步证实,菌株预处理可使发病率降至0。本研究为小麦赤霉病的生物防治提供了新的候选菌株,并为减少化学农药使用、促进农业可持续发展提供了科学依据。展开更多
基金supported by a grant from the National High Technology Research and Development Program of China (2006AA10A214)the Natural Science Foundation of Hebei Province,China (C2007000464)
文摘In order to understand the compsition and structure of herbicidal component of Pythium aphanidermatum,the isolation and structural indentification were researched.The culture filtrate was extracted by ethyl acetate,petroleum,and chloroform with the same volume respectively and the activity of the crude toxin was bioassayed.The toxin was separated by using the method of thin layer chromatography（TLC）,then the main fraction was separated by HPLC,and the structure was analyzed by the sepctrum of IR,13C-NMR and 1HNMR.The results showed that the ethyl acetate extracts had the strongest herbicidal activity.Using the method of TLC,the bioassay results showed that the extracts with Rf 0.19 had the strongest effect on weeds and the inhibition to Digitaria sanguinalis and Amaranthus retroflexus reached five levels,and the component was proved to be dimethyl o-phthalate from the spectrum of IR,13C-NMR and 1HNMR,which was one of the components from the toxin,and it had herbicidal activity.
文摘小麦赤霉病(Fusarium head blight,FHB)是由禾谷镰刀菌(Fusarium graminearum)引起的重要病害,不仅造成了严重产量损失,其产生的真菌毒素更威胁了粮食安全。该病害具有“可防不可治”的特点,目前主要依赖化学防治,但长期使用化学药剂易导致病原菌抗药性和环境污染。为开发绿色防控方法,本研究从小麦根际土壤中筛选获得13种生防菌,其中第12号菌株[鉴定为瓜果腐霉(Pythium aphanidermatum)]表现出显著抑菌效果。结果显示,该菌株在平板对峙实验中,使病原菌菌落直径减少69.2%(1.47 mm vs.对照组4.78 mm),抑制率达77%(P<0.01)。显微观察发现病原菌菌丝出现明显畸变,表明存在溶菌作用。胚芽鞘实验进一步证实,菌株预处理可使发病率降至0。本研究为小麦赤霉病的生物防治提供了新的候选菌株,并为减少化学农药使用、促进农业可持续发展提供了科学依据。
