Effect of plant root on rhizospheric microbes

Plant roots have a significant impact on the rhizosphere microbiome, the community of microorganisms that live in and around the root zone. Plant roots release a variety of exudates, including sugars, amino acids, and organic acids, which serve as a food source for microbes. These exudates also attract and recruit beneficial microbes to the rhizosphere.

In turn, rhizosphere microbes provide a number of benefits to plants, including:

• Nutrient acquisition: Microbes can help plants to acquire nutrients from the soil, such as nitrogen, phosphorus, and potassium. This is done through a variety of mechanisms, including nitrogen fixation, phosphate solubilization, and potassium mobilization.
• Plant growth promotion: Some microbes produce plant growth hormones, which can stimulate root growth, shoot growth, and flowering. Other microbes produce enzymes that can help plants to break down complex organic compounds in the soil.
• Disease resistance: Microbes can help plants to resist diseases by competing with pathogens for nutrients and space, or by producing antibiotics or other antimicrobial compounds.

Role of plant growth promoting rhizobacteria (PGPR) for improving crop productivity in sustainable agriculture

PGPR are a group of beneficial bacteria that live in the rhizosphere of plants. PGPR can promote plant growth and productivity in a number of ways, including:

• Nutrient acquisition: PGPR can help plants to acquire nutrients from the soil, such as nitrogen, phosphorus, and potassium. This is done through a variety of mechanisms, including nitrogen fixation, phosphate solubilization, and potassium mobilization.
• Plant growth promotion: PGPR produce plant growth hormones, such as auxins, cytokinins, and gibberellins. These hormones can stimulate root growth, shoot growth, and flowering.
• Disease resistance: PGPR can help plants to resist diseases by competing with pathogens for nutrients and space, or by producing antibiotics or other antimicrobial compounds.

PGPR can be used to improve crop productivity in sustainable agriculture by reducing the need for chemical fertilizers and pesticides. PGPR can also help plants to tolerate abiotic stresses, such as drought, salinity, and cold.

Here are some examples of how PGPR are being used to improve crop productivity in sustainable agriculture:

• Inoculating legumes with rhizobia: Rhizobia are a type of PGPR that can fix nitrogen from the air. Inoculating legumes with rhizobia can reduce or eliminate the need for nitrogen fertilizer.
• Using PGPR to improve phosphorus uptake: PGPR can help plants to solubilize phosphorus from the soil, making it more available to plants. This can be particularly beneficial in soils with low phosphorus availability.
• Using PGPR to control pests and diseases: PGPR can be used to control pests and diseases by competing with pathogens for nutrients and space, or by producing antibiotics or other antimicrobial compounds.

Overall, PGPR are a valuable tool for improving crop productivity in sustainable agriculture. PGPR can help plants to acquire nutrients more efficiently, resist diseases, and tolerate abiotic stresses. This can lead to reduced input costs and increased yields for farmers.

Dr Murthada Shukur thank you for your contribution to the discussion

Yes, plant roots grow through soil they mostly release water soluble compounds such as amino acids, sugars and organic acids that supply food for the microorganisms. High levels of exudates in the rhizosphere attract a plethora of microorganisms to a larger extend than elsewhere in the soil. Root exudates are known as one of the most important factors affecting microbial growth in the rhizosphere. As cell numbers are several orders higher in the root zone than in the background soil lacking plants. The microbial community is more diverse, active, and synergistic than in nonrhizosphere soil. The most important factors which affect / influence the microbial flora of the rhizosphere or rhizosphere effect are: soil type & its moisture, soil amendments, soil PH, proximity of root with soil, plant species, and age of plant and root exudates. These rhizobacteria also indirectly improve plant growth by inducing plant resistance to various biotic and abiotic stresses, such as pathogen attack and heavy metal contamination, using such mechanisms as the production of antibiotics, induction of induced systemic resistance, rhizosphere competence. The differential root exudates had strong impact on key bacteria than dominant bacteria, key fungi, and dominant fungi. Moreover, strigol had positively effects with bacteria, whereas phenolic compounds and chrysin were negatively correlated with rhizosphere microorganisms. Plant growth promoting rhizobacteria (PGPR) living on plant roots and promoting plant growth are critical to plant growth. These PGPRs exert their effects by facilitating food intake, helping to counteract pathogen attack, and regulating plant hormone levels. They are a secure and favorable alternative to chemical fertilizers as well as a useful option to decrease stress conditions. Many bacterial species act as PGPRs and have visibly improved plant growth, health, and productivity. They promote the plant growth by providing nutrients, hormones, and other plant growth substances. The carbon-rich root exudates provide nutrients to the microbes present in the rhizosphere. PGPR possess diverse functions such as symbiosis, nitrogen fixation, phosphate solubilization, etc. The rhizosphere conditions have a direct impact on crop growth and yield. Nutrient-rich rhizosphere environments stimulate plant growth and yield and vice versa. Extensive cultivation exhaust most of the soils which need to be nurtured before or during the next crop.