<p>Pigeonpea (<i>Cajanus cajan</i>&#xa0;(L.) Millsp.) is an important leguminous crop in tropical countries. However, the productivity of pigeonpea is adversely affected in central India due to impaired nodulation. Limited studies are available on pigeonpea rhizobia in central India. Therefore, the current study was undertaken to estimate the abundance and molecular diversity of pigeonpea rhizobia in order to identify improved strains for bio-inoculants. Rhizobial numbers in Vertisols of central India averaged 3864 ± 714 cells g⁻¹ of soil. In general, their abundance was&#xa0;tenfold higher in rhizosphere than in bulk soil. Rhizobia isolates retrieved from field nodules were screened, and 48 promising isolates were shortlisted based on their nodulation efficiency and promotion of plant growth for further characterization. Both slow-growing (56%) and fast (44%)-growing rhizobia were predominant and there were no significant differences in their nodulating ability. The fast-growing <i>Rhizobium</i> spp. utilized the various carbon sources tested to a greater degree than the slow-growing <i>Bradyrhizobium</i> spp. Fast growers were resistant to antibiotics such as chloramphenicol, vancomycin, kanamycin, gentamycin and polymyxin-B while slow growers were resistant to erythromycin, carbenicillin and penicillin-G. BOX-PCR analysis highlighted that rhizobia in Vertisols of central India exhibit a wide range of diversity. 16S rRNA gene sequences were homologous to <i>Bradyrhizobium</i> spp<i>.</i>,&#xa0;<i>Rhizobium</i> spp<i>.</i>,&#xa0;<i>Ensifer</i> spp., and <i>Mesorhizobium</i> spp. Novel genera like <i>Labrys, Ramlibacter, Sphingobium</i> and <i>Ciceribacter</i> were also found to nodulate pigeonpea. The slow-growing <i>Bradyrhizobum yuanmingense</i> isolates were the most efficient in nodulating ability and can be further explored as effective inoculants for enhancing productivity of pigeonpea in central India.</p>