The growing interest in using rhizobia as inoculants in sustainable agricultural systems has prompted the screening of rhizobia species for beneficial traits that enhance nodulation and nitrogen fixation under abiotic stressed conditions. This study reports phenotypic and phylogenetic characterization of rhizobia strains previously isolated from the root nodules of several indigenous and exotic legumes growing in South Africa and other countries. The Rhizobia strains were screened for their ability to tolerate various abiotic stresses (temperature 16, 28, and 36 °C; acidity/alkalinity pH 5, 7, and 9; heavy metals 50, 100, and 150 mM AlCl3.
View Article and Find Full Text PDFThe genome of strain SARCC-3054 was sequenced after being confirmed as a potential plant growth-promoting rhizobacteria in both and assays. The 6.3 MB genome has a GC content of 60.
View Article and Find Full Text PDFstrains BD1274 and BD1212 were isolated from seeds. Strain BD1274 induced a disease symptom on a healthy onion, whereas strain BD1212 did not and remains nonpathogenic. A comparative genomic study revealed that the strains differ in their genomic compositions, particularly in the genes that confer pathogenicity.
View Article and Find Full Text PDFspp., commonly referred to as due to the honey scented flowers, are indigenous legumes mainly growing in the Cape Floristic Region of the Western Cape, South Africa. Dozens of species, including are used to make the well-known, popular and widely enjoyed beverage called '.
View Article and Find Full Text PDFRecent developments in the legume rhizobium symbiotic interaction particularly those related to the emergence of novel strains of bacteria that nodulate and fix nitrogen in legumes is gaining momentum. These novel strains of bacteria were mostly isolated from the root nodules of indigenous and invasive legumes belonging to the sub families Papilionoideae and Mimosoideae in South Africa, South America and South East China. These rhizobia are phylogenetically and taxonomically different from the traditional 'alpha rhizobia' and are termed 'β-rhizobia' as they belong to the β-sub class of Proteobacteria.
View Article and Find Full Text PDFThe draft genome sequence of sp. strain SARCC-RB16n reveals the presence of major symbiotic ( and ) and additional plant growth-promoting (PGPR) genes associated with enhanced growth of (Burm. f.
View Article and Find Full Text PDFSARCC-755 is a free-living soil bacterium that formed nodules on pigeonpea roots in the present study. However, the draft genome sequence reveals that this species contains the gene but lacks the common nodulation () genes and probably uses other pathways to induce nodules on the legume plant.
View Article and Find Full Text PDFInduction of systemic tolerance in sorghum [Sorghum bicolor (L.) Moench] against drought stress was studied by screening a large collection of rhizobacterial isolates for their potential to exhibit this essential plant growth-promoting trait. This was done by means of a greenhouse assay that measured the relative change in both plant height and -biomass (roots and shoots) between rhizobacteria-primed versus non-primed (naïve) plants under drought stress conditions.
View Article and Find Full Text PDF(formerly ) is a wide-spread legume species indigenous to southern Africa. Little is known regarding the identity or diversity of rhizobia that associate with this plant in its native range in South Africa. The aims of this study were therefore: (i) to gather a collection of rhizobia associated with from a wide range of geographic locations and biomes; (ii) to identify the isolates and infer their evolutionary relationships with known rhizobia; (iii) to confirm their nodulation abilities by using them in inoculation assays to induce nodules under glasshouse conditions.
View Article and Find Full Text PDFTwelve nodulating Paraburkholderia strains isolated from indigenous South African fynbos legume Hypocalyptus sophoroides were investigated to determine their taxonomic status. Genealogical concordance analysis, based on six loci (16S rRNA, atpD, recA, rpoB, lepA and gltB), revealed that they separate into two consistent and exclusive groups. Average nucleotide identity and DNA-DNA hybridisation comparisons indicated that they were sufficiently divergent from their closest known phylogenetic relatives (Paraburkholderia caledonica and Paraburkholderia terrae, respectively) to be regarded as novel species.
View Article and Find Full Text PDFsp. strain Nafp2/4-1b is a rhizobacterium isolated from the rhizosphere of grassland in South Africa. This draft genome report confirms the presence of genes related to iron acquisition, alleviation of abiotic stress in plants, and other essential traits of plant growth-promoting rhizobacteria (PGPR) that signify the potential of this strain as a plant growth-promoting agent.
View Article and Find Full Text PDF