The impact of root exudates, volatile organic compounds, and common mycorrhizal networks on root system architecture in root-root interactions

ABSTRACT Plants constantly communicate with coexisting neighbors and adjust their physiological and morphological characteristics, including changes in root system architecture (RSA). Increased or decreased biomass accumulation, horizontal and vertical asymmetric distribution are the main behavioral performances. Some evidence has shown that these performances are associated with plant plasticity such as secretion of root exudates and release of volatile organic compounds (VOCs) and describe the role of common mycorrhizal networks (CMNs) as a communication pathway during belowground interplant interaction. Here, we highlight the direct role of root exudates as cues and signals and the indirect effects via regulating soil nutrients and soil microorganisms of these media in root-root interactions on RSA have been taken into consideration. At last, the existing knowledge gaps and potential research directions have been outlined for a better understanding of plant belowground interactions via RSA.