Mechanistic Insights of the Interaction of Plant Growth-Promoting Rhizobacteria (PGPR) With Plant Roots Toward Enhancing Plant Productivity by Alleviating Salinity Stress.

Mujtaba Aamir Bhat,Rubina Koser,Iqra Farooq,Farha Bhatti,Ishfaq Ahmad Wani,Farhana Latief Dar,Safikur Rahman,Vijay Kumar,Mudasir Ahmad Bhat,Arif Tasleem Jan

doi:10.3389/fmicb.2020.01952

Abstract

Agriculture plays an important role in a country’s economy. The sector is challenged by many stresses, which led to huge loss in plant productivity worldwide. The ever-increasing population, rapid urbanization with shrinking agricultural lands, dramatic change in climatic conditions, and extensive use of agrochemicals in agricultural practices that caused environmental disturbances confront mankind of escalating problems of food security and sustainability in agriculture. Escalating environmental problems and global hunger have led to the development and adoption of genetic engineering and other conventional plant breeding approaches in developing stress-tolerant varieties of crops. However, these approaches have drawn flaws in their adoption as the process of generating tolerant varieties takes months to years in bringing the technology from the lab to the field. Under such scenario, sustainable and climate-smart agricultural practices that avail bacterial usage open the avenues in fulfilling the incessant demand for food for the global population. Ensuring stability on economic fronts, bacteria minimizes plant salt uptake by trapping ions in their exopolysaccharide matrix besides checking the expression of Na+/H+ and high-affinity potassium transporters. Herein we describe information on salinity stress and its effect on plant health as well as strategies adopted by plant growth-promoting rhizobacteria (PGPR) in helping plants to overcome salinity stress and in mitigating loss in overall plant productivity. It is believed that acquisition of advanced knowledge of plant-beneficial PGPR will help in devising strategies for sustainable, environment-friendly, and climate-smart agricultural technologies for adoption in agriculture to overcome the constrained environmental conditions.

Highlights

With rapid urbanization, the reduction in agricultural land left less space to expand the cultivation of plants
Required for cell division and elongation in plants, the inoculation of ST-plant growth-promoting rhizobacteria (PGPR) P. putida modulated internal indole-3-acetic acid (IAA) pools that resulted in an increase in the growth parameters in cotton plants grown under salinity stress (Yao et al, 2010; Egamberdieva et al, 2017)
Though much progress has been made in understanding the different attributes of plant–microbe interactions and in formulating methodologies for crops grown under salinity stress, we still lag behind in achieving sustainability in plant productivity

Summary

Introduction

The reduction in agricultural land left less space to expand the cultivation of plants. Solute accumulation, enhanced expression of SOS1, EREBP, SERK1, and NADP-Me2 ACC deaminase activity; improves the growth of plants in water-stressed rain-fed environments Enhanced expression of SOS-related genes, increased tissue-specific expression of ion transporters, modulation of ABA signaling cascade ACC deaminase activity, minimizes the salinity-induced oxidative damages to the plants Root dry weight and shoot biomass

Results

Conclusion