知识与财富的链接
为阐明中国玉米镰孢穗腐病的主要致病镰孢菌种类及其分布特征,采用形态学、培养特征及特异性分子鉴定方法,对采集自我国18省100个县的玉米籽粒样品进行分离鉴定,并通过TEF-1α基因序列测定解析禾谷镰孢复合种的构成.结果表明,在我国引起玉米穗腐病的主要致病菌为镰孢菌,分离频率为56.0%,其次还有青霉菌、曲霉菌、木霉菌等.138个镰孢菌分离物中鉴别出7个种及复合种,其中拟轮枝镰孢菌Fusarium verticillioides(56.5%)和禾谷镰孢复合种F.graminearum species complex(37.7%)为广泛分布的优势致病种类,其余为黄色镰孢菌F.culmorum(2.2%)、层出镰孢菌F.proliferatum(1.5%)、尖镰孢复合种F.oxysporum species complex(0.7%)、茄镰孢复合种F.solani species complex(0.7%)和亚粘团镰孢菌F.subglutinans(0.7%).在禾谷镰孢复合种中鉴定出3个独立种:广泛分布的禾谷镰孢菌F.graminearum sensu stricto(59.6%)、分布在云南、贵州及陕西商洛等南方生态区的南方镰孢菌F.meridionale(25.0%)和分布在内蒙古、吉林、山西、河北及北京等北方生态区的布氏镰孢菌F.boothii(11.5%).
Based on morphology, cultural characters and species-specific molecular detection, 130 kernel samples collected from 100 counties in 18 provinces of China were identified, and the species in Fusarium graminearum species complex were analyzed by comparing TEF-1α gene sequences. The results showed that the species of Fusarium were mainly pathogens (56.0%) causing maize ear rot in China, and other fungi were Penicilium spp., Aspergillus spp., Trichoderma spp. and Alternaria spp. In the 138 isolates of Fusarium, seven species were identified, including widely distributed F.verticillioides (56.5%) and F.graminearumspecies complex (37.7%), and others were F.culmorum (2.2%), F.proliferatum (1.5%), F.oxysporum species complex (0.7%), F.solani species complex (0.7%) and F.subglutinans (0.7%). In the isolates of F.graminearum species complex, three species were identified, including widely distributed F.graminearum sensu stricto with the frequency of 59.6%, F.meridionale (25.0%) only found in southern maize-growing zone and F.boothii (11.5%) in northern ecological zone.
