唐古特大黄根腐病病原菌的鉴定

Identification of Root Rot Pathogens of Rheum Tanguticum

本文通过对青海省果洛州班玛县多娘村和佐洛村唐古特大黄根腐病发病组织进行病原菌的分离纯化、形态特征观察和ITS区序列分子生物学鉴定。结果表明,唐古特大黄根腐病的致病菌2种,一种是菌株ZgB在ITS区序列对比中与狭截盘多毛孢菌(Truncatella angustata)序列匹配率、覆盖度、相似度最高,且在系统发育树中与之处于同一分支且同源性最高。另一种是菌株dgA在ITS区序列对比中与角担菌(Ceratobasidium sp.)序列匹配率、覆盖度、相似度最高,且在系统发育树中与之处于同一分支且同源性最高。初步推测,本次多娘村大黄根腐病是由狭截盘多毛孢菌和角担菌混合侵染引起,佐洛村大黄根腐病是狭截盘多毛孢菌侵染引起。

In this study,the pathogenic bacteria were isolated and purified,morphological characteristics were observed and ITS region sequence molecular biology was identified in the root rot disease infected tissues of rheum tanguticum in duoniang village and zuoluo village,bama county,goluo prefecture,qinghai province.The results showed that there were 2 kinds of pathogenic bacteria of root rot of Rheum tanguticum.One was ZgB which had the highest sequence matching rate,coverage and similarity with Truncatella angustata in ITS region sequence comparison,and was in the same branch and the highest homology with it in phylogenetic tree.The other was the strain dgA which had the highest sequence matching rate,coverage and similarity with Ceratobasidium sp.in the sequence comparison of ITS region,and was in the same branch with it in the phylogenetic tree with the highest homology.It was preliminarily speculated that the root rot of rhubarb in Duoniang Village was caused by the mixed infection of Truncatella angustata and Ceratobasidium sp.,and the root rot of rhubarb in Zuoluo Village was caused by Truncatella angustata.