ABSTRACT

Soils present in various agroecosystems differ in their composition of abiotic and biotic components which exert remarkable influence on the development of plants from seed/propagule germination, to growth and maturity of grains and other plant produce. Soil provides anchorage and nutrients for the emerging seedlings and transplants till they attain harvest stage. The availability of nutrients from soil to plants depends on the fertility of the soil derived from the organic matter and minerals (fertilizers) that are added naturally or artificially. In addition, the microorganisms present in the soil may be beneficial to the development of plants by fixing atmospheric nitrogen and decomposing complex organic matter into easily available forms. In contrast, some of them may be harmful by infecting roots/stems or aerial parts of plants at different stages of plant growth, causing a range of adverse effects (diseases), resulting in the debilitation and ultimately the death of plants. As these microorganisms cause several economically important diseases, it is essential to establish their identity rapidly and reliably by employing appropriate technique(s), depending on their morphological, biological, biochemical, immunological and genetic properties.