Symbiotic performance and characterization of Pigeonpea (Cajanus cajan L. Millsp.) Rhizobia occurring in South African soils

Loading...
Thumbnail Image

Authors

Bopape, Francina L.
Beukes, Chrizelle W.
Kopotsa, Katlego
Hassen, Ahmed I.
Steenkamp, Emma Theodora
Gwata, Eastonce T.

Journal Title

Journal ISSN

Volume Title

Publisher

MDPI

Abstract

Pigeonpea (Cajanus cajan (L.) Millsp.) is an important grain legume, which, like several other legumes, depends on the process of biological nitrogen fixation for its nitrogen (N2 ) requirement by forming a symbiotic association with rhizobia. Compared to other tropical legumes, however, the productivity of pigeonpea in South Africa is low, despite the extensive interests in developing it for wider markets. To assist this process, the objectives of the current study were to (i) characterize putative indigenous rhizobial strains that were previously derived from local soils with no previous history of legume cultivation and (ii) confirm their nodulation abilities on a local landrace and a genetically improved (exotic) genotype of pigeonpea. DNA-based analyses using the 16S rRNA and recA genes showed that the strains predominantly represented Rhizobium and Bradyrhizobium, although we also recovered Phyllobacterium and Paraburkholderia. These rhizobia nodulated both the local landrace and the improved pigeonpea genotype that were included for comparative purposes. In many cases, rhizobia performed similarly on the two genotypes, although the locally sourced landrace mostly performed better in terms of nodulation and plant biomass. While the current study generated vital information regarding the diversity of indigenous rhizobia associating with pigeonpea, further screening (including field inoculation trials) would be necessary to identify possible elite nitrogen-fixing rhizobial strains for development as inoculants to enhance South African pigeonpea production.

Description

Keywords

Grain legume, Nodulation, Plant growth promotion, Alphaproteobacteria, Betaproteobacteria

Sustainable Development Goals

Citation

Bopape, F.L.; Beukes, C.W.; Katlego, K.; Hassen, A.I.; Steenkamp, E.T.; Gwata, E.T. Symbiotic Performance and Characterization of Pigeonpea (Cajanus cajan L. Millsp.) Rhizobia Occurring in South African Soils. Agriculture 2023, 13, 30. https://doi.org/10.3390/agriculture13010030.