The phylogenetic relationships and distribution of Ralstonia pseudosolanacearum and Ralstonia solanacearum sequevars were analyzed in 108 strains of Solanaceae in three mesoregions of the Pernambuco State, Brazil. These mesoregions are characterized by a semiarid climate and account for 88.20% of the area of the state. Ralstonia pseudosolanacearum (phylotype I, biovar 3) was predominant in Agreste, and R. solanacearum (phylotype II, biovar 1) was predominant in São Francisco and Sertão. Two haplotypes of R. pseudosolanacearum were identified by analysis of the haplotype network of the partial egl gene sequences and were phylogenetically related to sequevars I-17 and I-18. Five haplotypes of R. solanacearum were identified; two haplotypes were related to sequevar IIA-50, and three haplotypes were related to new sequevars IIA-61, IIA-62, and IIA-63. In Brazil, sequevars I-17, IIA-61, IIA-62, and IIA-63 were detected exclusively in the semiarid climate of Pernambuco, unlike sequevars I-18 and IIA-50, which were detected in other regions of Brazil. Furthermore, R. pseudosolanacearum (phylotype I) and sequevar IIA-50 were detected in the Sertão mesoregion. Sequevar I-18, IIA-61, and IIA-62 strains were prevalent in the Agreste mesoregion, and sequevars I-17 and IIA-50 were prevalent in the São Francisco mesoregion. The virulence variability of the strains toward tomato was related to species and sequevars. Introduced R. pseudosolanacearum strains of sequevar I-18 had higher estimated virulence compared to that of the native R. solanacearum strains of sequevar IIA-50. This is the first study that analyzes the variability of Ralstonia spp. in the semiarid region of Brazil.

的亲缘关系和分配青枯pseudosolanacearum和青枯病sequevars在108株茄科在伯南布哥州，巴西三个mesoregions进行了分析。这些中部地区的特点是半干旱气候，占该州面积的88.20％。阿格列斯特主要以假单胞菌（Ralstonia pseudosolanacearum）（I型，生物变种3）为主，圣弗朗西斯科和塞尔托省以青枯菌（R. solanacearum）（II型，生物变种1）为主。通过分析部分蛋黄的单倍型网络，鉴定了假单胞菌的两个单倍型。基因序列，并且在遗传上与后代I-17和I-18相关。鉴定了五种青枯菌单倍型。两个单倍型与后代IIA-50相关，三个单倍型与新后代IIA-61，IIA-62和IIA-63相关。在巴西，Sequevars I-17，IIA-61，IIA-62和IIA-63仅在伯南布哥半干旱气候中被检测到，这与在巴西其他地区检测到的Sequevars I-18和IIA-50不同。此外，假单胞菌在Sertão中部地区检测到（I型）和Sequevar IIA-50。Sequevar I-18，IIA-61和IIA-62菌株在阿格里斯特中部地区盛行，Sequevars I-17和IIA-50菌株在圣弗朗西斯科中部地区盛行。菌株对番茄的毒力变异性与物种和后代有关。引入R. pseudosolanacearum相比于天然的sequevar I-18的菌株具有较高的估计的毒力青枯sequevar IIA-50的菌株。这是分析Ralstonia spp变异性的第一项研究。在巴西的半干旱地区。