鲁西南地区小麦茎基腐病病原菌鉴定及其致病力分析

为明确山东小麦茎基腐病害主要致病菌组成及其致病力，于2016年在山东省聊城、德州、临沂市共7个地点采集了具有典型茎基腐症状的病株并对其主要致病菌进行了分离、鉴定和致病力分析。结果共分离到45株病原真菌，其中有22株为镰孢菌，分别属于假禾谷镰孢菌（Fusarium pseudograminearum）、禾谷镰孢菌（F.graminearum）和亚洲镰孢菌（F.asiaticum），以假禾谷镰孢菌（F.pseudograminearum）分离频率最高，占所有镰孢菌株的68.18%；其余菌株属于链格孢菌（Alternaria spp.）。对22株镰孢菌进行小麦苗期致病力及重分离率测定发现，假禾谷镰孢菌（F.pseudograminearum）的致病力明显强于禾谷镰孢菌和亚洲镰孢菌，后两者的致病力相差不大；3种病原菌的重分离率均大于40%，病原菌测序鉴定结果与接种病原菌一致。

Identification and Pathogenicity of Pathogens Associated with the Wheat Crown Rot in the Southwest of Shandong Province

To understand pathogenicity and composition of the main pathogens causing wheat crown rot in the southwest of Shandong province, we collected a large number of diseased wheat plants with suspected crown rot symptoms from seven locations of Liaocheng, Dezhou and Linyi, and the major pathogens were isolated and identified,and pathogenicity was analysed. The results showed that 45 pathogenic strains were obtained, of which a total of 22 isolates belong to genus Fusarium, including F.pseudograminearum, F.graminearum and F.asiaticum,and the isolation frequency of F.pseudograminearum was the highest, accounting for 68.18%.The other strains were belong to Alternaria spp. The pathogenicity of 22 isolates of Fusarium spp. were tested at seedling stage of wheat with artificial inoculation method in greenhouse. The results indicated that the pathogenicity of F.pseudograminearum was obviously stronger than that of other two Fusarium species, and the pathogenicity between F.graminearum and F.asiaticum were found no significant difference. We also isolated the pathogens from diseased plants with typical crown rot symptom after inoculation. The re-isolation percentage of the three Fusarium species reached up to more than 40%. Based on molecular data, it was indicated that the pathogens-derived from re-isolation and that of inoculation were the same species of Fusarium.