Unlocking Soil Potential: Potassium-Solubilizing Fungi from Paddy Rhizosphere | InformativeBD

R. Ranjitha, and Alagappan Gandhi, from the institute of India. wrote a Research Article about, Unlocking Soil Potential: Potassium-Solubilizing Fungi from Paddy Rhizosphere. Entitled, Efficacy of Potassium Solubilizing Fungi isolated from the Rhizospheric Soil of Paddy. This research paper published by the International Journal of Biosciences (IJB). an open access scholarly research journal on Biosciences. under the affiliation of the International Network For Natural Sciences| INNSpub. an open access multidisciplinary research journal publisher.

Abstract

Improving soil fertility is essential for enhancing agricultural productivity, with potassium (K) being a crucial nutrient for plant growth. In soil, potassium is predominantly found in insoluble forms, making it unavailable to plants. This study aims to identify and evaluate fungal strains capable of solubilizing insoluble potassium sources to improve soil fertility. Soil samples were collected from paddy fields in Pudukkottai, Tamil Nadu, and potassium-solubilizing fungi were isolated using modified Aleksandrov agar and Potato Dextrose Agar media. Ten fungal isolates were screened for their ability to solubilize potassium, with KSF1 demonstrating the highest solubilization index (SI) of 1.51. Quantitative analysis revealed that KSF1, identified as Aspergillus niger, released the highest amount of potassium from mica (42.16 mg/25 ml) on the 10th day of incubation. This isolate showed superior solubilization capabilities compared to others. The findings suggest that Aspergillus niger KSF1 is a highly effective potassium solubilizer, offering a sustainable approach to enhancing soil fertility and supporting agricultural productivity.

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Introduction

Improving soil fertility is one of the most common methods of agricultural production. Potassium (K) is one of the most important plant nutrients for increasing plant production. In plants, K plays a vital role in numerous biochemical and physiological activities such as photosynthesis, respiration, energy generation, nucleic acid biosynthesis cell, osmotic regulation, and enzyme activation (Masood and Bano, 2016). Most soil potassium, around 98%, is in the form of insoluble potash and cannot be used by plants and just 1-2% is available for plants Meena et al., (2016).To enhance potassium availability for plants, large amounts of fertilizer are regularly applied in the fields. However, many of these fertilizers are converted to insoluble forms after application and require continuous reapplication (Kang et al., 2002). Microorganisms are essential to the natural potassium cycle, with certain fungal strains in the soil capable of dissolving minerals such as mica, feldspar, and potassium aluminium silicate. Filamentous fungi, especially those from Aspergillus species, produce significant quantities of organic acids, which are essential for breaking down insoluble substrates containing potassium (B. Bagyalakshmi, 2012; Basak et al., 2022; Lian et al., 2008; Samah M. et al., 2023). The various microorganisms and minerals capable of releasing potassium from minerals have been recently reviewed (Etesami et al., 2017; Sharma et al., 2016). The fungus has been reported to have a higher solubility of insoluble potassium than bacteria.

A wide range of soil fungi are reported to dissolve insoluble phosphorus such as Aspergillus niger, which is the most common fungus having the ability to dissolve potassium-bearing minerals. The goal of this research is to find fungi that can bind potassium from various forms of potassium that are unavailable. If successful, this could provide a sustainable and environmentally friendly method of boosting agricultural yields and improving soil fertility.

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Source : Efficacy of Potassium Solubilizing Fungi isolated from the Rhizospheric Soil of Paddy