Characterization of Root Nodule and Nodulation in Legume Plants

Eboigbe, Lugard; Jesuoghae, Osamagbe; Dudun, Aye-Mola G.

doi:10.21608/eajbsh.2025.434000

Characterization of Root Nodule and Nodulation in Legume Plants

Document Type : Original Article

Authors

Department of Plant Biology and Biotechnology, University of Benin, PMB 1154 Benin City, Nigeria

10.21608/eajbsh.2025.434000

Abstract

Legumes are essential crop for global agriculture, forming symbiotic relationships with nitrogen fixing bacteria, enhancing soil fertility and reducing fertilizer needs. It possesses a distinctive capacity to establish symbiotic associations with rhizobia, resulting in the formation of root nodules that assimilate atmospheric nitrogen. This research characterized root nodules and nodulation in four (4) legume strains; three (03) common beans (Phaseolus vulgaris) White Beans, Brown Beans, Ekpoma Local Variety and one (01) Groundnut (Arachis hypogeae). This research primarily focused on understanding root nodules and nodulation in legume plants. We also explored the connections between the number of leaves, the number of nodules, and the size of these nodules. Our findings revealed a positive correlation between nodule number and nodule size, meaning more nodules generally led to larger nodules. However, we observed a negative correlation between leaf number and nodule number, suggesting that an increase in leaves was associated with a decrease in the number of nodules. Significant variability in nodule number formation was recorded among legumes (Arachis hypogaea and Phaseolus vulgaris); the most nodules were recorded in BB2 ( brown beans) andWBK3 (white beans) . In a controlled experiment conducted using sterilized soil, our findings suggests that, while rhizobia plays a crucial component in nodulation they are not the exclusive necessity as the need for other factors is highlighted and that the number of nodules can serve as a valid gauge for nodule size and N₂ fixing ability. Thus, providing implications for the selection and breeding of legume strains to enhance nitrogen fixation and bio-fertilizer output in sustainable agriculture.

Keywords