The Role of Plant Growth-Promoting Bacteria in the Growth of Cereals under Abiotic Stresses

Abstract

Plant growth-promoting rhizobacteria (PGPR) are known to improve plant performance by multiple mechanisms, such as the production of beneficial hormones, the enhancement of plant nutritional status, and the reduction of the stress-related damage. The interaction between plants and PGPR becomes of particular interest in environments that are characterized by suboptimal growing conditions, e.g., high or low temperatures, drought, soil salinity, and nutrient scarcity. The positive role of PGPR will become even more appealing in the future, as world agriculture is facing issues as climate change and soil degradation. This chapter aims to discuss the main mechanisms of the interaction between PGPR and plants and will focus of how PGPR can decrease abiotic stress damage in cereals, which are critical crops for human diet.

Microbiome Fingerprint as Biomarker for Geographical Origin and Heredity in Crocus sativus: A Feasibility Study

“…Proteobacteria are the main microbial contributors to plant growth promoting rhizobacteria (PGPR), reported so far. They are fast growing and play a role in diverse metabolic activities that enhance plant growth (Philippot et al, 2013;Rampelotto et al, 2013;Schillaci et al, 2019;Mukhtar et al, 2020). Actinobacteria are the gram positive bacteria that are known to promote plant growth and having biocontrol activity (Viaene et al, 2016).…”

Effects of Combined Stresses of Salinity (NaCl) and Heavy Metal (NiCl2) Levels on Seed Germination and Growth of Citrullus colocynthis l.

“…The obstructive water content of seeds due to salinity and heavy metal stress leads to a decline in the activity of enzymes especially hydrolytic enzymes which have a key role to hydrolyze cotyledonous reserve food required for supplying energy by respiration during the early stages of seed growth. Limitation of water uptake, transfer of seed stocks, and direct influence on gene expression and organic structure is related to salinity and heavy metal stresses (Schillaci et al, 2019). An important reason behind the reduced seed germination may be the inhibited nutrient delivery from seed storage tissues to the developing embryo (Joshi, 2018).…”

Current perspectives and applications in plant probiotics

“…Within the rhizosphere, microorganisms play a crucial role in phosphate availability, they are also a source of nitrogen via diazotrophic nitrogen fixation and present a barrier (much like oral microflora in humans) to incoming pathogens (reviewed in 12 ). The rhizosphere is an environment rich in organic acids, become increasingly impacted by climate change 13 . Other mechanisms of PGP in the rhizosphere include the solubilisation and mobilisation of occluded phosphates.…”

“…Microorganisms can mine phosphate from soil and increase the amount of labile phosphorous available to plants. Research in this area of plant probiotics is extensive and will not be covered in this review, but for further reading see 8,[12][13][14][15] .…”