Authors : Mahesh A. Naikwade; Tejas B. Kapadnis; Shubham S. Nikale

Volume/Issue : Volume 11 - 2026, Issue 4 - April

Google Scholar : https://tinyurl.com/4zfw76a8

DOI : https://doi.org/10.38124/ijisrt/26apr1116

Note : A published paper may take 4-5 working days from the publication date to appear in PlumX Metrics, Semantic Scholar, and ResearchGate.

Abstract : Soil microorganisms contribute significantly to nutrient cycling and the maintenance of soil fertility in agricultural ecosystems. Among beneficial microorganisms, species belonging to the genus Azotobacter are recognized for their capacity to fix atmospheric nitrogen and stimulate plant growth through multiple biochemical activities. The present investigation was conducted to isolate and characterize Azotobacter species from rhizospheric soils collected from major crop fields in Ahilyanagar district, Maharashtra, India. A total of twenty soil samples were obtained from the root zones of crops such as sugarcane, onion, pigeon pea, maize and wheat.The collected soil samples were examined to determine their physicochemical characteristics, specifically pH, moisture level, and capacity to retain water, following established analytical protocols. Bacterial isolates were obtained through serial dilution and plating techniques and subsequently screened on Ashby’s mannitol agar for the selective recovery of Azotobacter. Colony morphology, Gram staining, and biochemical assays including catalase activity, starch hydrolysis, and nitrate reduction were used for characterization of isolates. Twenty bacterial strains were recovered from the soil samples and designated as ANAZO-1 to ANAZO-20. Among these isolates, fourteen strains showed characteristics consistent with Azotobacter, while the remaining isolates displayed different phenotypic features. The analyzed soil samples exhibited pH values ranging from 5.6 to 6.7, indicating slightly acidic to near-neutral conditions. Moisture content ranged from 29.25% to 49.37%, while water-holding capacity varied between 31.90% and 51.25%. The occurrence of Azotobacter species in the rhizosphere suggests their potential contribution to soil fertility and crop productivity. These isolates may serve as promising candidates for future development of biofertilizer formulations aimed at sustainable agricultural practices.

Keywords : Azotobacter, Rhizospheric Soil, Biofertilizer, Nitrogen fixation, Soil Microbiology.

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