Fertilization of Microbial Composts: A Technology for Improving Stress Resilience in Plants

Abstract

Microbial compost plays a crucial role in improving soil health, soil fertility, and plant biomass. These biofertilizers, based on microorganisms, offer numerous benefits such as enhanced nutrient acquisition (N, P, and K), production of hydrogen cyanide (HCN), and control of pathogens through induced systematic resistance. Additionally, they promote the production of phytohormones, siderophore, vitamins, protective enzymes, and antibiotics, further contributing to soil sustainability and optimal agricultural productivity. The escalating generation of organic waste from farm operations poses significant threats to the environment and soil fertility. Simultaneously, the excessive utilization of chemical fertilizers to achieve high crop yields results in detrimental impacts on soil structure and fertility. To address these challenges, a sustainable agriculture system that ensures enhanced soil fertility and minimal ecological impact is imperative. Microbial composts, developed by incorporating characterized plant-growth-promoting bacteria or fungal strains into compost derived from agricultural waste, offer a promising solution. These biofertilizers, with selected microbial strains capable of thriving in compost, offer an eco-friendly, cost-effective, and sustainable alternative for agricultural practices. In this review article, we explore the potential of microbial composts as a viable strategy for improving plant growth and environmental safety. By harnessing the benefits of microorganisms in compost, we can pave the way for sustainable agriculture and foster a healthier relationship between soil, plants, and the environment.

Keywords: PGPR; biofertilizer; compost; nutrient transformation; plant diseases.

Figure 1

Schematic representation of the composting process.

Figure 2

Schematic representation of the compost-based biofertilizers. Mycorrhizal fungal filaments and plant-growth-promoting rhizobacteria in the soil act as to support the development of the plant root system and are more effective at water and nutrient absorption than the roots themselves. PGPR and AMF also explore the soil and reach places unattainable to roots and increase nutrient uptake by plants from the soil. Their effects on plant growth through two different mechanisms, such as direct mechanism and indirect mechanism, are illustrated.