广豆根根腐病病原鉴定

Identification of Pathogens Causing Root Rot of Sophora tonkinensis

目的:鉴定引起广豆根根腐病的病原菌,为广豆根根腐病病害的防治提供理论依据。方法:通过组织分离法分离得到病原菌,对其形态特征的观察及该菌rDNA-ITS序列的测定,并与Gen Bank中的序列进行比对。结果:该菌在PDA培养基上菌落圆形,气生菌丝薄绒状,白色,浅灰色,间有土黄色分生孢子座,基物表层肉色。小型分生孢子数量多,卵形、肾形,8～16μm×2.5～4μm;大型分子孢子马特型,多数3～5个隔膜。该菌rDNA-ITS序列长度为553 bp,它与Fusarium solani(登录号为:AB518683.1、AB470903.1、AB369488.1、AJ608989.1、GQ365154.1、EF152426.1)和Fusarium oxysporum(登录号为:GQ922558.1、GQ922559.1、DQ452447.1)的序列同源性均达99%。结论:结合以上两种鉴定方法,得出引起广豆根根腐病的病原菌为半知菌类镰孢霉属真菌茄腐镰孢菌Fusarium solani。

Objective： To identify the pathogens what caused of root rot,it can provide method of theoretical gist of integrated pest management of these kinds of diseases in the future.Methods： Pathogens from rotten root of Sophora tonkinensis were isolated by tissue isolation.Their morphological characteristics were observed and rDNA-ITS sequence were sequenced,then analyzed by Blast in Gen-Bank.Results： Round colony in PDA medium,The aerial mycelium was thin,white,light gray and yellowish brown eustroma was on the surface of material.The surface of base material was flesh.Large number of small conidia ware oval,kidney-shaped,8 ～ 16 μm × 2.5 ～ 4 μm.And the large conidia just like Matt spore type,which had 3 to 5 septums.The length of rDNA-ITS of the fungi was 553 bp,which the ITS region sequences compared with the sequence of Fusarium solani（accession number： AB518683.1,AB470903.1,AB369488.1,AJ608989.1,GQ365154.1,EF152426.1）,and Fusarium oxysporum（accession number： GQ922558.1,GQ922559.1,DQ452447.1） homology reached 99%.Conclusion： Combination of two identification methods,it arrived at the cause of root rot pathogen fungi was Fusarium solani.