Nodulation patterns and influencing factors in chickpea fields of Nagpur district: A regional survey

Abstract

Biological nitrogen fixation is crucial for enhancing soil fertility and reducing reliance on chemical fertilizers, with chickpeas benefiting from their symbiotic relationship with Mesorhizobium ciceri to convert atmospheric nitrogen into a usable form. This study assessed the nodulation status of chickpea (Cicer arietinum L.) in the Nagpur region, focusing on nodule density and functionality and their association with plant stage, variety, and location. A comprehensive survey was conducted across 11 tehsils in the Nagpur district, covering 44 villages and 120 fields. Chickpea plants were sampled from three fields per village, and nodules were counted after washing the roots to differentiate between total and active nodules. The survey revealed significant variability in nodulation across Nagpur, with the highest total nodules per plant recorded in Navegaon (57.48) and Awarmara (54.78), and the lowest in Bori (22.56) and Bhiwapur (23.45). Active nodule counts were highest in Navegaon (25.87) and Awarmara (24.65), while Bhiwapur (11.02) and Koradi (11.85) had the lowest. Correlation analysis showed a strong association between total and active nodules (r = 0.994) but weak correlations with plant stage and variety. This indicated that soil conditions, climate, and rhizobial strains were more critical for nodulation success than growth stage or variety. Further research is required to optimize these factors to improve chickpea productivity.