Plant health: feedback effect of root exudates-rhizobiome interactions

Abstract

The well-being of the microbial community that densely populates the rhizosphere is aided by a plant’s root exudates. Maintaining a plant’s health is a key factor in its continued existence. As minute as rhizospheric microbes are, their importance in plant growth cannot be overemphasized. They depend on plants for nutrients and other necessary requirements. The relationship between the rhizosphere-microbiome (rhizobiome) and plant hosts can be beneficial, non-effectual, or pathogenic depending on the microbes and the plant involved. This relationship, to a large extent, determines the fate of the host plant’s survival. Modern molecular techniques have been used to unravel rhizobiome species’ composition, but the interplay between the rhizobiome root exudates and other factors in the maintenance of a healthy plant have not as yet been thoroughly investigated. Many functional proteins are activated in plants upon contact with external factors. These proteins may elicit growth promoting or growth suppressing responses from the plants. To optimize the growth and productivity of host plants, rhizobiome microbial diversity and modulatory techniques need to be clearly understood for improved plant health.

Plant Growth Promoting Rhizobacterial Mitigation of Drought Stress in Crop Plants: Implications for Sustainable Agriculture

“…Thus, LCOs are crucial signaling molecules within the rhizosphere, which stimulates plant growth enhancement and could have an impact on plant nutrition via modification of the root structure [165]. The effect of LCOs on nutrient uptake enhancement in plants was reported in Medicago truncalata by Oláh et al [166], who observed an improvement in the number of lateral roots of the plant when LCOs were applied [167]. In the same way, a positive improvement in the root architecture of Arabidopsis thaliana was observed when plants were treated with LCOs from Bradyrhizobium japonicum.…”

“…In the same way, a positive improvement in the root architecture of Arabidopsis thaliana was observed when plants were treated with LCOs from Bradyrhizobium japonicum. This resulted in an increase in the root surface area, the number of root tips, as well as the root lengths of A. thaliana treated plants [167,168].…”

Inoculation with a microbe isolated from the Negev Desert enhances corn growth

“…A more robust and developed root system was observed in the bacteria-treated plants. Stimulation of root growth and effective root area for enhanced water and nutrient uptake is a very important stress management tool because a healthy and proliferated root system helps the plant maintain optimal growth and development under stress conditions (Olanrewaju et al, 2019;Mendes et al, 2013).…”

A novel biosensor to monitor proline in pea root exudates and nodules under osmotic stress and recovery

“…Plant root exudates are composed of a great variety of primary and secondary metabolites, including low-molecular weight compounds such as sugars, amino acids and organic acids, as well as high-molecular weight molecules such as mucilage and proteins (Bais et al 2006;Oburger and Jones 2018). The different molecules present in root exudates can mediate both positive and negative interactions in the rhizosphere (Huang et al 2014;Olanrewaju et al 2019). Focusing on the former, the symbiosis established between plants of the Leguminosae family and a group of alpha-proteobacteria named rhizobium has been widely studied.…”