水稻纹枯病是严重影响水稻生产的真菌病害,水稻相对病斑高度法作为评估立枯丝核菌AG-1 IA致病力的传统方法,需要将水稻培养至分蘖末期或抽穗期,再进行活体接种,耗时耗力,且试验条件不易控制。本研究以水稻相对病斑高度法(活体接种)为对照,利用水稻离体叶鞘法和离体叶片法测定了水稻纹枯病菌致病力和粗毒素活性,比较活体接种法与离体接种法的相关性。结果表明水稻离体叶片法、水稻离体叶鞘法和水稻相对病斑法测定致病力和粗毒素活性结果均呈显著正相关,水稻离体叶片法和离体叶鞘法测定结果能够准确反映立枯丝核菌AG-1 IA的致病力和粗毒素活性,离体评估方法操作方便,试验条件易于控制。因此,水稻离体叶片法、叶鞘法可以替代活体接种法作为测定立枯丝核菌AG-1 IA致病力和粗毒素活性的方法。水稻离体叶片法、叶鞘法与活体接种法结合起来可作为测定立枯丝核菌AG-1 IA毒素活性测定的新方法。本研究的结果还表明,水稻不同组织对水稻纹枯病菌毒素敏感性不同,水稻的叶鞘组织比叶片组织对纹枯病菌敏感。由于粗毒素的致病力与活体菌株接种的致病力存在显著差异,因此纹枯病菌毒素以外的致病因子,也是不容忽视的。在定量分析立枯丝核菌AG-1 IA与水稻的互作中,需要将不同水稻的组织进行区分,才能更加精准地了解互作机制。 Rice sheath blight is a serious fungal disease affecting rice production. Relative height of rice lesion as a traditional method to assess the pathogenicity of Rhizoctonia solani AG-1 IA, the rice needs to be cultured until the late tillering stage or heading stage, Vaccination in vivo, time-consuming and labor-intensive, and the test conditions are not easy to control. In this study, the relative disease lesion height (inoculation) of rice was used as control. The pathogenicity and crude toxin activity of Rhizoctonia solani were determined by leaf sheath method and in vitro leaf method. Compared with inoculation and in vitro Law relevance. The results showed that there was a significant positive correlation between pathogenicity and crude toxin activity of rice in vitro leaf sheath method, rice leaf sheath method and rice relative spot method, the isolated leaf method and isolated leaf sheath method can accurately reflect the results The pathogenicity and the crude toxin activity of Rhizoctonia solani AG-1 IA were evaluated by in vitro methods and the experimental conditions were easy to control. Therefore, in vitro leaf method and leaf sheath method could be used as an alternative to inoculum method for determining pathogenicity and crude toxin activity of Rhizoctonia solani AG-1 IA. In vitro leaf method and leaf sheath method combined with inoculation method could be used as a new method to determine the activity of AG-1 IA toxin in Rhizoctonia solani. The results of this study also show that different tissues of rice have different sensitivity to R. solani toxins, and leaf sheaths of rice are more sensitive to R. solani than leaf tissues. Since the virulence of crude toxin is significantly different from the virulence of live strains, virulence factors other than Rhizoctonia solani can not be ignored. In quantitative analysis of Rhizoctonia solani AG-1 IA interaction with rice, different rice tissues need to be distinguished in order to understand the interaction mechanism more accurately.