Root exometabolites as an ecological factor in the interaction between cultivated plants and soil micro­organisms

Abstract

The results of the analysis of scientific literature sources regarding the role of root exometabolites in the interaction between cultivated plants and soil microorganisms are presented. It has been proven that root exometabolites are recognized by rhizospheric microorganisms, which, in turn, produce signaling molecules and initiate various plant reactions in response to colonization. The main functions of root exometabolites are considered and their specific features are given depending on the type of plants and the stage of their development. The results of research on the positive influence of the rhizosphere microbiome on the growth and development of plants, which is due to the secretion of plant growth hormones by growth-stimulating bacteria, solubilization of nutrients, antagonism to pathogens and induction of the plant immune system, are presented. The components of protective metabolic systems of plants against soil phytopathogenic microorganisms that provide biomolecules of phenolic compounds are described. Mechanisms of regulation of interaction both at the level of molecular and ultrastructural changes of the cell, and at the level of biochemical and physiological processes are highlighted. The participation of transporter proteins in the synthesis and exudation of protective phytochemicals, which can be modified by the soil microbiome, is shown. Plant signaling molecules induce hyphal branching of micromycetes and trigger morphogenesis of fungal hyphae, which precedes successful colonization. The peculiarities of vesicular-arbuscular mycorrhiza, the induced root exudates of which contribute to both the development of microbial associations in the rhizosphere and plant growth, are considered. The interaction of plants with soil microorganisms plays an important role in the resistance of plants to heavy metals, for example by reducing their bioavailability in the soil using various mechanisms. The study of root exometabolites of plants will allow a better understanding of the interaction of plants and microorganisms, which determines their role as an ecological factor in microbial-plant associations.