Rhizobia is a group of gram-negative soil-borne bacteria with several beneficial strains for biological nitrogen fixation in legume crops. Rhizobium strains are found native in the soil but where they are absent, commercial strains are inoculated on crops. We assessed the availability of native rhizobia in chickpea fields at two sites, with contrasting soil types, in NE South Africa. Serial dilutions were used to identify bacteria from soil samples and chickpea nodules sampled before sowing and at flowering, respectively. Our results indicated the absence of rhizobia strains at both sites. Burkholderia cenocepacia, Klebsiella variicola, Bacillus subtilis and Ochrobactrum spp, which are not important in agriculture but are often reported in clinical environments, were identified. Therefore, inoculating chickpea with compatible rhizobia strains may be necessary in some soils in this region.

根瘤菌是一组革兰氏阴性土壤传播细菌，具有几种有益的菌株，可用于豆类作物的生物固氮。在土壤中发现了根瘤菌菌株，但没有根瘤菌，将商业菌株接种到作物上。我们评估了南非东北部两个地区不同土壤类型的鹰嘴豆田中天然根瘤菌的有效性。连续稀释用于分别从播种前和开花时取样的土壤样品和鹰嘴豆节中鉴定细菌。我们的结果表明在两个位点都没有根瘤菌菌株。洋葱伯克霍尔德菌，水痘克雷伯菌，枯草芽孢杆菌和O牙菌属，确定了在农业中不重要但经常在临床环境中报道的那些。因此，在该地区的某些土壤中可能需要用相容的根瘤菌菌株接种鹰嘴豆。