摘要
Actually, in Republic of Congo, rhizobia have poorly phenotypically and biochemically characterized. This study aimed to characterize native rhizobia. Rhizobia strains were isolated using nodule roots collected on <i><span style="font-family:Verdana;">Milletia laurentii</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Acacia spp</span></i><span style="font-family:Verdana;">., </span><i><span style="font-family:Verdana;">Albizia lebbeck</span></i><span style="font-family:Verdana;">,</span><i> </i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Vigna unguiculata</span></i><span style="font-family:Verdana;">. The strains isolated were characterized microbiologically, biochemically, physiologically, and molecularly identified using 16S rRNA method. The results reported in this study are only for six strains of all 77 isolated: RhA1, RhAc4, RhAc15, RhAc13, RhW1, and RhV3. All native strains were positive to urease activity, negative to cellulase and pectinase activity except for one isolate that showed a positive cellulase activity. Moreover, isolates have grown at 12% of NaCl. On different effects of temperatures, isolates were able to grow up to 44</span><span style="font-family:;" "=""><span style="font-family:Verdana;">°C and showed good growth at pH from 7 to 9 and the ability to use ten different carbon hydrates sources. The strains were identified as </span><i><span style="font-family:Verdana;">Rhizobium tropici</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Rhizobium sp</span></i><span style="font-family:Verdana;">., </span><i><span style="font-family:Verdana;">Mesorhizobium sp</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">Bradyrhizobium yuanmingense</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Bradyrhizobium elkanii</span></i><span style="font-family:Verdana;">. The phylogenetically analysis of the 16S rRNA genes, using a clustering method, allowed us to have a history that is both ancient and stable of four clades among genes with similar patterns. Expanding our awareness of the new legume-rhizobia will be a valuable resource for incorporating an alternative nitrogen fixation approach to consolidate the growth of legumes. These germs can be used in Congolese agriculture to improve yield of crops.</span></span>
Actually, in Republic of Congo, rhizobia have poorly phenotypically and biochemically characterized. This study aimed to characterize native rhizobia. Rhizobia strains were isolated using nodule roots collected on <i><span style="font-family:Verdana;">Milletia laurentii</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Acacia spp</span></i><span style="font-family:Verdana;">., </span><i><span style="font-family:Verdana;">Albizia lebbeck</span></i><span style="font-family:Verdana;">,</span><i> </i><span style="font-family:Verdana;">and</span><i><span style="font-family:Verdana;"> Vigna unguiculata</span></i><span style="font-family:Verdana;">. The strains isolated were characterized microbiologically, biochemically, physiologically, and molecularly identified using 16S rRNA method. The results reported in this study are only for six strains of all 77 isolated: RhA1, RhAc4, RhAc15, RhAc13, RhW1, and RhV3. All native strains were positive to urease activity, negative to cellulase and pectinase activity except for one isolate that showed a positive cellulase activity. Moreover, isolates have grown at 12% of NaCl. On different effects of temperatures, isolates were able to grow up to 44</span><span style="font-family:;" "=""><span style="font-family:Verdana;">°C and showed good growth at pH from 7 to 9 and the ability to use ten different carbon hydrates sources. The strains were identified as </span><i><span style="font-family:Verdana;">Rhizobium tropici</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Rhizobium sp</span></i><span style="font-family:Verdana;">., </span><i><span style="font-family:Verdana;">Mesorhizobium sp</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">Bradyrhizobium yuanmingense</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Bradyrhizobium elkanii</span></i><span style="font-family:Verdana;">. The phylogenetically analysis of the 16S rRNA genes, using a clustering method, allowed us to have a history that is both ancient and stable of four clades among genes with similar patterns. Expanding our awareness of the new legume-rhizobia will be a valuable resource for incorporating an alternative nitrogen fixation approach to consolidate the growth of legumes. These germs can be used in Congolese agriculture to improve yield of crops.</span></span>
