烟草青枯病菌分离株RSXJ-1的培养性状及其生物型鉴定

Cultural Characteristics and Biotype Identification of Isolate RSXJ-1 of Ralstonia solanacearum

从江西省峡江县烟区采集呈典型症状的青枯病烟株,采用平板梯度稀释分离法分离获得一株病原菌分离株,命名为RSXJ-1。在完成致病性测定的基础上,通过分子生物学方法将该菌株鉴定为茄科劳尔氏菌(Ralstonia solanacearum)。本文研究了该菌株在不同培养基上的培养性状,结果表明该菌株的培养性状与R.solanacearum的培养性状相一致;对该菌株进一步进行生物型研究,结果显示该菌株能利用乳糖、麦芽糖、纤维二糖、甘露醇和山梨醇氧化产酸并能还原硝酸盐;而不能利用甜醇氧化产酸,据此将该菌株鉴定为生物型Ⅲ-1。

A tobacco plant with typical symptoms of bacterial wilt was collected from Xiajiang county of Jiangxi province.A bacterial isolate was obtained from the plant using gradient dilution isolation method,ant it was named RSXJ-1.With completion of its pathogenicity test,the isolate was identified molecularly as Ralstonia solanacearum.This paper investigated the cultural characteristics of the bacterial isolate on different media.The results showed that cultural characteristics of the bacterial isolate were consistent with the cultural characteristics of R.solanacearum.Experiment of biotype identification of the isolate was also conducted.The results showed that the isolate had the ability of both oxdizing lactose,maltose,cellobiose,mannitol,and sorbitol to produce acid and reducing nitrate.However,it had no ability of oxdizing dulcitol to produce acid.According to the results,the isolate was identified as biotype Ⅲ-1 of R.solanacearum.