Enhancing soil health and plant growth promotion by actinomycetes

Abstract

In recent times, numerous concrete efforts have been made by global scientific community for maintenance and judicious utilization of certain non-renewable natural resources like metal ores, fossil fuels and to an extent groundwater. However, soil, an important non-renewable asset, has received little attention and demands more awareness and exploration by researchers worldwide. Soil regeneration through chemical and biological processes of rock weathering takes several thousand years; thus, soil is classified as a vital, finite and non-renewable source. Soil health, thus, becomes a critical factor for humans, animals, plants and all natural ecosystems. Soil health deterioration, increased by industrialization and indiscriminate use of chemical fertilizers, has become a major environmental concern with high precedence. Public awareness to these problems has shifted approach to alternative strategies like using plant growth-promoting rhizobacteria (PGPR), also popular as bio-fertilizers, for achieving cleaner, safer and cost-effective increase in agricultural productivity. Amongst several bacteria reported as PGPR, actinomycete is one of the most promising options due to properties like nutrient cycling, antibiosis, rhizosphere competence and beneficial plant growth-promoting (PGP) traits. In this chapter, we intend to discuss about how actinomycetes are crucial as PGPR in maintaining soil health, fertility and agricultural productivity and investigate underlying PGPR mechanisms. We shall also briefly enlist few successful PGP actinomycetes, challenges associated and future implications to increase soil fertility.