Bacterial wilt, caused by the soil-borne bacterium Ralstonia solanacearum, is a lethal disease of tomato, but the molecular mechanisms of the host resistance responses to R. solanacearum remain unclear. In this study, we report the first work describing the transcriptome of cultivar resistance and susceptible tomato cultivar after inoculation with R. solanacearum. To elucidate the characteristi...

Previously, we isolated several genes that potentially affected the expression of type III secretion system (T3SS) in Ralstonia solanacearum OE1-1. Here, we focused on the rsp0316, which encodes a putative 2-nitropropane dioxygenase (hereafter designated NpdA). The deletion of npdA substantially reduced the T3SS expression and virulence in OE1-1, and the complementation with functional NpdA cou...

Ralstonia solanacearum is a causative agent of bacterial wilt and therefore poses serious threat to cultivated peppers (Capsicum annuum L.). Although attempts have been made control by grafting, the disease resistance mechanisms that protect grafted are poorly understood. Here, we grew composed rootstock Buyeding or Weishi scion Xinfeng 2. Following infection R. solanacearum, assessed differenc...

The plant pathogen Ralstonia solanacearum has two genes encoding for the sigma factor σ(54): rpoN1, located in the chromosome and rpoN2, located in a distinct "megaplasmid" replicon. In this study, individual mutants as well as a double mutant of rpoN were created in R. solanacearum strain GMI1000 in order to determine the extent of functional overlap between these two genes. By virulence assay...

Ralstonia solanacearum phages ΦRP12 and ΦRP31 are jumbo phages isolated in Thailand. Here we show that they exhibit similar virion morphology, genome organization and host range. Genome comparisons as well as phylogenetic and proteomic tree analyses support that they belong to the group of ΦKZ-related phages, with their closest relatives being R. solanacearum phages ΦRSL2 and ΦRSF1. Compared wi...

The study was undertaken to assess whether seedling age played any role in governing the vulnerability of tomato to the bacterial wilt pathogen, Ralstonia solanacearum, based on the preliminary observations that the extent of mortality during seedling-stage screening was relatively less in older seedlings. Employing the virulent strain ‘NH-Av01’ isolated from tomato, 2-, 3-, 4or 5-weekold seedl...

This study aims to isolate and identify the causal pathogen of tomato bacterial wilt in Egypt. In 2008, tomato plants showing typical symptoms of bacterial wilt disease with no foliar yellowing were observed in Minia, Assiut and Sohag governorates, Egypt. When cut stems of symptomatic plants were submerged in water, whitish ooze was evident and longitudinal sections showed a brown discoloration...

Most strains of the bacterial wilt pathogen Ralstonia solanacearum are tropical, but race 3 biovar 2 (R3bv2) strains can attack plants in temperate zones and tropical highlands. The basis of this distinctive ecological trait is not understood. We compared the survival of tropical, R3bv2, and warm-temperate North American strains of R. solanacearum under different conditions. In water at 4 degre...