摘要： 为鉴定芝麻种质对不同病源区茎点枯病原菌的抗性差异,用来源于河南南阳、河南平舆和湖北武汉3个病区的芝麻茎点枯菌株,采用牙签接种法于芝麻生长苗期对30份芝麻种质材料进行接菌试验.结果显示:平舆菌株接种的供试材料发病最严重,30份供试材料中共有23份材料的病斑长度均值大于南阳和武汉菌株接种引起的病斑长度值,感病种质所占比例较大,鉴定出4份抗平舆菌株且与其他材料差异显著的抗性种质,而未发现对南阳菌株和武汉菌株表现抗性且差异显著的抗性种质.聚类分析表明:由3种菌株接种的供试材料中病斑长度10 cm以下的种质都聚在Ⅰ类,大于10 cm的都聚在Ⅱ类,可视病斑长度10 cm为抗性与敏感之间的分界线;对南阳和武汉病菌的抗性聚类图相似,Ⅰ类中材料数较多,地方种质主要聚在Ⅰ类中,而对平舆的抗性聚类图显示Ⅰ和Ⅱ材料数相当,地方和改良种质数在两类中的分布也相近;有10份种质抗性相对较好,可进行抗性利用.

关键词: 芝麻, 茎点枯病, 抗病性, 鉴定

Abstract: Sesame is usually suffered from Macrophomina phaseolina and induced charcoal rot.The study was designed to identified sesame gerplasm resistant differences to Macrophomina phaseolina from different sources.Three strains of Macrophomina phaseolina from Nanyang,Pingyu in Henan province and Wuhan in Hubei province were inoculated into 30 sesame materials by means of toothpick at seedling stage.The results showed that strain from Pingyu had highest pathogenicity as it induced longer disease spots than that from Nanyang and Wuhan,and 23 materials had longer average disease spots than that from the other two places in 30 tested materials.Most tested materials were seriously infected except for WB01,08-3354,08-3368 and PS48.However,these materials showed no significant difference to the pathogen strains from Nanyang and Wuhan.Cluster analysis showed the materials with disease spots less than 10 centimeters induced by the three strains were always divided intoⅠgroups,and the others fell into groupⅡ.Thus,the disease spot size of 10 centimeters could be taken as the standard for distinguishing the tolerance and susceptibility of sesame.The cluster result based on the disease spot size that induced by the pathogen strain from Nanyang was similar to that from Wuhan.They all showed more materials were clustered into groupⅠ,especially for the landraces.In contrast,cluster for Pingyu showed groupⅠand Ⅱwere considerable in the number of materials,and also in the rate of landraces and improved lines.The study figured out 10 materials that could be used for breeding for their resistance to Macrophomina phaseolina.

Key words: Sesame, Macrophomina phaseolina, Disease resistance, Identification

中图分类号: 

• S435

• S565.3