黄淮海夏玉米主产区穗腐病病原菌的分离鉴定

为明确我国黄淮海夏玉米主产区玉米穗腐病的病原菌种类、优势种群及虫害、年度、省份对病原菌的影响,以形态学为基础,结合分子生物学方法对2013、2015年随机采自河南、河北、山东3省的155份玉米穗腐病样品进行分离鉴定。结果表明,引起黄淮海夏玉米主产区玉米穗腐病的主要致病菌为镰孢菌Fusarium spp.,包括拟轮枝镰孢F.verticillioides、禾谷镰孢F.graminearum、层出镰孢F.proliferatum、木贼镰孢F.equiseti及藤仓镰孢F.fujikuroi,分离频率分别为49.7%、28.4%、12.3%、3.9%和1.3%;其次为木霉菌Trichoderma spp.,包括哈茨木霉T.harzianum、绿色木霉T.viride和棘孢木霉T.asperellum,分离频率分别为8.4%、3.2%和5.2%;青霉菌Penicillium spp.分离频率较低,为14.2%;曲霉菌Aspergillus spp.包括黑曲霉A.niger和黄曲霉A.flavus,分离频率分别为2.6%和1.9%。研究表明,黄淮海主产区玉米穗腐病优势病原菌为拟轮枝镰孢、禾谷镰孢和木霉菌,不同省份不同年度间病原菌种类及优势病原菌存在差异,虫害能加重玉米穗腐病的发生。

Isolation and identification of pathogens causing maize ear rot in Huang-Huai-Hai summer corn region

In order to confirm the pathogenic species, predominant population and the influence of pest, years and provinces on pathogens in maize ear rot in the Huang-Huai-Hai summer corn region, 155 samples of maize ear rot were collected randomly from Henan, Hebei and Shandong provinces in 2013 and 2015. The pathogens were isolated and identified from cankered maize ears with morphological and molecular methods. The results showed that some species of Fusarium spp., including F. verticillioides, F. graminearum, F. proliferatum, F. equiseti and F. fujikuroi, were the main pathogens causing the maize ear rot in Huang-Huai-Hai summer corn region, the isolation frequencies were 49.7%, 28.4%, 12.3%, 3.9% and 1.3%, respectively. Trichoderma spp., including T. harzianum, T. viride and T. asperellum, were the secondary pathogens, the isolation frequencies were 8.4%, 3.2% and 5.2%, respectively. The isolation frequencies of Penicillium spp. was 14.2%. Aspergillus spp. including A. niger and A. flavus, the isolation frequencies were 2.6% and 1.9%, respectively. The results indicated that F. verticillioides, F. graminearum and Trichoderma spp. were the main pathogens of Huang-Huai-Hai summer corn re-gion, there existed difference in the species of pathogens and dominant pathogen between different provinces and years, and pests could also aggravate the occurrence of maize ear rot.