Chapter 18 - Ecological and structural attributes of soil rhizobiome improving plant growth under environmental stress

Abstract

Environmental stresses have many effects on the soil rhizosphere. Climate changes in different climates lead to an increase in abiotic stresses, for example, salinity, drought, heat, cold, flood, and various biotic stresses. Pathogens such as fungi, bacteria, and viruses also greatly reduce agricultural productivity. In this situation, the use of chemical fertilizers and poisons, which lead to adverse effects on the products, has increased. In such conditions, plant growth promoting rhizobacteria (PGPR) are environmentally friendly and sustainable candidates to combat these stresses. PGPR help to improve these stresses in the rhizosphere using several mechanisms and has beneficial effects on plant growth after treatment at the plant root level. Plant growth stimulation through PGPR is the result of the secretion and production of many secondary metabolites that act through different mechanisms in the plant. Bacterial inoculations also increase nutrient uptake and crop growth. Therefore, they may be good supplements for chemical fertilizers and agricultural chemicals. Rapid progress in rhizosphere microbiome research has strengthened the belief that plants interact with various microbial communities and PGPRs and cope with stressors. In the past decade, many PGPRs that improve crop production under stress have been used to revitalize agricultural systems. In this chapter, we discuss the beneficial effects of PGPRs on the growth and development of plants under environmental stresses such as salinity and drought.