【作者】 游倩； 刘小兰； 许莉萍； 阙友雄； 陈如凯；

【机构】 福建农林大学国家甘蔗产业技术研发中心；

【摘要】 由甘蔗黑穗病菌(Ustilago scitaminea Syd.)引起的甘蔗黑穗病是我国蔗区最重要的真菌性病害。为了解该病原菌的分子分化,对采集自全国7个省(区)、38个甘蔗栽培品种上的100个甘蔗黑穗病菌菌株进行单孢分离和培养,利用真菌通用性引物和甘蔗黑穗病菌特异性引物,逐一对其进行PCR标记验证,并进一步通过目标片段克隆和测序分析,确认了这些单孢培养物的正确性。而后,从18条ISSR引物中,筛选出7条具有良好多态性的引物,用于对这100个甘蔗黑穗病菌分离物进行遗传多样性分析。结果表明,每条引物的多态性位点平均为15个,多态性位点率为86.8%。100个分离物样本的相似系数分布在0.4628～0.9008,平均为0.6587,遗传多样性属于中等水平。在遗传距离为0.015水平处,可将100份甘蔗黑穗病菌菌株聚为3个群体。经过遗传相似系数、聚类和主成分分析,显示甘蔗黑穗病菌分离物间的相异程度与其地理来源的相关性高于与寄主品种来源的相关性。研究结果有利于更全面和深入地了解我国该病原的情况,并有助于甘蔗抗黑穗病育种。根据遗传距离分析,粤糖89-113、云蔗03-194、ROC16与NCo310(感1小种)几乎一致,表明这3个品种也是1小种的寄主。更多还原

【Abstract】 Sugarcane smut caused by Ustilago scitaminea Syd.is the most important fungal disease in sugarcane cultivation in China.100 pathogen strains,which come from 7 provinces and 38 sugarcane genotypes,were used for single spore isolation and culure.Both of current primers for detection of fungi and special primers for detection of U.scitaminea was used to identify these strains.Besides,cloning and sequence analysis of the target band were carried out for advanced testification.The seven ISSR primers with good polymorphic potencial were selected from 18 ISSR primers by experiment and were used for analysis of genetic diversity.The results showed that the average polymorphic loci per primer pair was 15 and the percentage of polymorphic loci was 86.8%.The genetic similarity indexes of 100 varieties ranged from 0.4628 to 0.9008 with an average of 0.6587,which implied that the genetic diversity among the pothogen strains was at middle level.At the genetic distance of 0.015,these 100 strains could be divided into three clusters.According to the results of the genetic similarity coefficient,clustering and principal component analysis,the values of dissimilarity between the strains in different geographical origin was higher than those in different host origin,ie.genotypes.The rests obtained in this study were conducive to go deep into understanding the pathogen in China and were contributive to sugarcane breeding for smut resistance.更多还原