海南玉米穗腐病病原菌分离鉴定及优势种的遗传多样性分析

为了阐明海南省玉米穗腐病病原菌的种类,结合形态学和分子生物学方法对83份病样进行了病原菌的分离和鉴定,最终获得12种病原菌,包括拟轮枝镰孢(Fusarium verticillioides)、层出镰孢(F.proliferatum)、亚粘团镰孢(F.subglutinans)、木贼镰孢(F.equiseti)、新知镰孢(F.andiyazi)、棘孢木霉(Trichoderma asperellum)、拟康宁木霉(T.koningiopsis)、卵孢木霉(T.ovalisporum)、喙刚毛球腔菌(Exserohilum rostratum)、玉蜀黍平脐蠕孢(Bipolaris maydis)、草酸青霉(Penicillium oxalicum)和可可毛色二孢(Lasiodiplodia theobromae)。其中,拟轮枝镰孢分离频率占65.06%,为优势种。以拟轮枝镰孢的EF-1α、histone 3和β-tubulin基因序列为基础进行多基因家系分析,以明确海南省与内陆部分省份不同菌株之间的遗传关系。结果表明,海南省内菌株之间具有丰富的遗传多样性,而且海南省和内陆省份菌株之间存在高频率的基因交流。

Characterization of the maize ear rot pathogens and genetic diversity analysis of dominant species in Hainan

In order to clarify the population of pathogens causing maize ear rot in Hainan Province, the pathogenic organisms were isolated from 83 diseased samples and 12 different species including Fusarium verticillioides, F. proliferatum, F. subglutinans, F. equiseti, F. andiyazi, Trichoderma asperellum, T. koningiopsis, T. ovalisporum, Setosphaeria rostrata, Bipolaris maydis, Penicillium oxalicum and Lasiodiplodia theobromae were identified by molecular method and morphological characteristics. Among these pathogens, F. verticillioides, the dominant agent, accounted for 65.06% of the total isolates. The genetic relationships among different strains of F. verticillioides from Hainan and inland Provinces were then evaluated by multigene genealogical analysis based on the EF-1α, histone 3 and β-tubulin gene sequences. The results showed that there was abundant genetic diversity among Hainan strains and a high frequency of gene exchange were also detected between Hainan and inland strains.