Vol. 11, Special Issue 1 (2022)

Author(s):
BL Dudwal, Sunita Koodi, SK Dudwal, Sheeshpal Choudhary and Manju Choudhary

Abstract:
Iron (Fe) in the soil mostly present in the form of insoluble Fe (III) oxides and hydroxides. The total iron in soil is much higher than most crops require. However, the concentration of free Fe (III) in most agricultural soils is below that required for optimal plant growth. Generally, chelation of Fe (III) is the most successful mechanism by which plants roots can acquire Fe. Production of chelating compounds by microorganisms increases Fe solubility in the rhizosphere and hence increases plant Fe acquisition. Bacterial siderophores, fungal siderophores and other chelating metabolites are assumed to serve as major sources of plant-available Fe in the rhizosphere. In cultivated soils iron is oxidized to form ferric oxide and oxy hydroxides results in low availability of iron for living organisms. To face the demand of Fe (III) in the rhizosphere leads to strong competition for this nutrient among living organisms, plants and microorganisms have developed active strategies of iron uptake. Efficient siderophores of microbial populations from the rhizosphere do not compete with the plant harboring them and even seems to contribute to the plant iron nutrition. The complex interaction between soil chemical properties, plants, and microbes affects the iron dynamics in the rhizosphere and later on affect the plant health and nutrition.