Characterization
of nodulation and nitrogen fixation potential of selected wild legumes of semiarid
region, Tirupati, India
Bhargava Y. and Murthy J.S.R.
Res. J. Biotech.; Vol. 20(12); 148-158;
doi: https://doi.org/10.25303/2012rjbt1480158; (2025)
Abstract
Bioavailability of nitrogen is one of the major nutrients limiting crop plant growth
and yield in agroecosystems worldwide. Symbiotic / Biological Nitrogen Fixation
(BNF) by legumes and associative, endosymbiotic and endophytic nitrogen fixation
in non-legumes play major role in reducing the use of synthetic nitrogen fertilizer
in agriculture, increased plant nutrient content and soil health reclamation and
potential economic gains to farmers in terms of input cost. Fifteen native wild
legumes and cultivated Arachis hypogaea were selected from the semi-arid region,
Tirupati to study nodule morphology and nitrogen fixation potential. The similarity
matrix was used for cluster analysis to construct a phenogram using the unweighted
pair group method with averages (UPGMA). The wild species included Indigofera mysorensis,
a new addition to the global list and a report of nodulation in Albizia lebbeck,
Mimosa pudica and Tephrosia tinctoria from India.
Morphological features of the nodule are characteristic of the species. There is
a positive correlation between intensity of nodule interior colour and nitrogenase
activity. All the species are highly effective nitrogen fixers and three-fold variation
was observed among the species. Nodule morphological features and nitrogenase activity
grouped 16 legumes into 5 distinct clusters at 65% level indicating the diversity.
