安徽凤阳玉米穗腐病病原菌的分离鉴定

目的]明确凤阳玉米穗腐病的病原菌种类。方法]在凤阳玉米种植区采集玉米穗腐病样品,采用组织分离法对病样进行分离与纯化,结合病原菌形态学特征与分子生物学进行鉴定。结果]分离得到的56株病原菌分别为禾谷镰孢菌(Fusarium graminearum)、尖孢镰孢菌(Fusarium oxysporum)、串珠镰孢菌(Fusarium verticillioides)、多变根毛霉(Rhizomucor variabilis)和青霉菌(Penicillium spp.),其分离频率分别为44.64%、21.42%、14.29%、14.29%和5.36%。禾谷镰孢菌Fg21菌丝生长温度为5~30℃,最适生长温度为25℃,最适pH为7.0;尖孢镰孢菌Fa09菌丝生长温度为10~35℃,最适生长温度为28℃,最适pH为7.0;串珠镰孢菌Fv03菌丝生长温度为10~35℃,最适生长温度为25℃,最适pH为10.0;碳源对镰孢菌菌株营养生长影响相对稳定,而氮源对其营养生长影响的变幅较大。结论]试验结果为玉米穗腐病的综合防治提供了理论依据。

Isolation and Identification of the Pathogen of Maize Ear Rot in Fengyang,Anhui Province

Objective] The aim was to know the pathogens causing maize ear rot in Fengyang.Method] The maize ear rot samples were collect-ed from Fengyang County.The tissue isolation method was adopted to isolate the maize disease samples,and then purified them.The pathogens were identified based on results of morphological characteristics and molecular biology. Result] Fifty-six isolates were identified as members of Fusarium gra minearum,Fusarium oxysporum,Fusarium verticillioide,Rhizomucor variabilis and Penicillium spp.,and the isolation frequency were 44.64%,21.42%,14.29%,14.29% and 5.36%,respectively.In this experiment,Fusarium gra minearum was the predo minant species in maize ear rot.The Fusarium gra minearum Fg21 could grow under 5-30 ℃,with optimal condition at 25 ℃,pH 7.0;the Fusarium oxysporum Fa09 could grow unde 10-35℃,with optimal condition at 28℃,pH 7.0;the Fusarium verticillioide Fv03 could grow unde 10-35℃,with opti-mal condition at 25℃,pH 10.0.Vegetative growth of Fg21,Fa09 and Fv03 were found to be significantly influenced by nitrogen source compared with carbon source.Conclusion] The results provide theoretical basis for comprehensive prevention and control of maize ear rot.