河南省花生青枯病菌的分子鉴定及其生物学特性研究

Molecular Identification and Biological Characterization of Ralstonia solanacearum Infecting Peanuts in Henan Province

为了明确河南省花生青枯病的病原菌分类属性,对采自河南省内不同市的30个青枯病菌株在16S rDNA序列、碳水化合物利用、致病性、演化型及序列变种等方面进行了鉴定。30个青枯病菌株的16S rDNA测序结果表明,引起河南花生青枯病的病原为茄科雷尔氏菌(Ralstonia solanacearum);所有青枯病菌株可侵染茄子、辣椒、马铃薯、烟草和番茄,但不侵染姜,属于生理小种1号;根据能否利用3种双糖和3种己醇的能力,可将其中4个菌株归于生化型Ⅱ,10个菌株归于生化型Ⅲ,16个菌株归于生化型V;所有青枯病菌株均能用多重PCR扩增得到144 bp演化型Ⅰ特异条带和280 bp茄科雷尔氏菌特异条带,表明青枯病原菌均属于茄科雷尔氏菌演化型Ⅰ,即亚洲组13;利用egl基因的系统发育进化分析表明,来自河南的30个菌株与Gx525、Ah-XnJn-12-6、HA2-1聚为一支,属于序列变种14。

To identify the taxonomic properties of the pathogen of peanut bacterial wilt disease in Henan Province,30 strains collected from different regions in Henan Province were comparatively characterized in terms of 16S rDNA sequences,carbohydrate utilization,pathogenicity,evolutionary type,and sequence variation.The results showed that,based on the 16S rDNA sequencing results of these 30 strains,the pathogen causing peanut wilt disease was R.solanacearum;all the strains could infect eggplant,chili pepper,potato,tobacco,and tomato,but did not infect ginger and belonged to physiological race 1;based on the analysis of the ability to utilize three disaccharides and three hexanols,four strains were classified as biovarⅡ,10 strains as biovarⅢ,and 16 strains as biovar V;all the strains were able to produce 144 bp specific band for evolutionary typeⅠand 280 bp specific band for R.solanacearum through multiplex PCR amplification,which indicated that all of the strains belonged to the evolutionary typeⅠ,i.e.,the Asian group 13 of R.solanacearum;based on the phylogenetic analysis of the egl gene,all the strains from Henan were clustered together with Gx525,Ah⁃XnJn⁃12⁃6,and HA2⁃1,belonging to sequence variant 14.