Soil Bacteria Support and Protect Plants Against Abiotic Stresses

The objective of this synthesis paper is to review the pivotal role of plant growth-promoting bacteria in developing sustainable systems for crop production under abiotic stress conditions. In this review, much research information about salt-stress has been gathered because soil salinity, which limits crop yield and restricts use of land, is a major constrain to food production. We start by reviewing the root zone bacteria that have been found to possess plant growth-promoting properties. We then review how plant growth-promoting bacteria act as enhancers of the main biochemical and molecular mechanisms developed by plants to cope with salt stress. We then discuss the potential role that agronomic manipulations can play in ameliorating the impact of salinity stress on plants. The body of studies suggests that, under abiotic stress conditions, the use of improved PGPR inoculants might be advantageous for the development of sustainable agriculture in which yield losses are reduced and plant growth is improved.