Flavonoid mediated selective cross-talk between plants and beneficial soil microbiome

Abstract

Plants generate a wide variety of organic components during their different growth phases. The majority of those compounds have been classified as primary and secondary metabolites. Secondary metabolites are essential in plants’ adaptation to new changing environments and in managing several biotic and abiotic stress. It also invests some of its photosynthesized carbon as secondary metabolites to establish a mutual relationship with soil microorganisms in that specific niche. As soil harbors both pathogenic and beneficial microorganisms, it is essential to identify some specific metabolites that can discriminate beneficial and pathogenic ones. Thus, a detailed understanding of metabolite’s architectures that interact with beneficial microorganisms could open a new horizon of ecology and agricultural research. Flavonoids are used as classic examples of secondary metabolites in this study to demonstrate recent developments in understanding and realizing how these valuable metabolites can be controlled at different levels. Most of the research was focused on plant flavonoids, which shield the host plant against competitors or predators, as well as having other ecological implications. Thus, in the present review, our goal is to cover a wide range of functional and signalling activities of secondary metabolites especially, flavonoids mediated selective cross-talk between plant and its beneficial soil microbiome. Here, we have summarized recent advances in understanding the interactions between plant species and their rhizosphere microbiomes through root exudates (flavonoids), with a focus on how these exudates facilitate rhizospheric associations. Supplementary Information The online version contains supplementary material available at 10.1007/s11101-022-09806-3.

Fe-Based Nanomaterial-Induced Root Nodulation Is Modulated by Flavonoids to Improve Soybean (Glycine max) Growth and Quality

“…In addition, Fe 3 O 4 NMs significantly improved genistin content by 119.4–624.7% compared to the unexposed control and EDTA-Fe treatments, Fe–P NMs increased daidzein content by 14.8% in rhizosphere soil compared to the unexposed control (Figure S8). The up-regulation of flavonoids in the rhizosphere by Fe-based NMs could facilitate cross-talk between the soybean and rhizosphere microbiome, and trigger the activation of nodulation genes to start legume-rhizobium symbiosis …”

“…The up-regulation of flavonoids in the rhizosphere by Fe-based NMs could facilitate cross-talk between the soybean and rhizosphere microbiome, and trigger the activation of nodulation genes to start legume-rhizobium symbiosis. 49 Flavonoids are scarcely synthesized in organs or plants grown in the dark because the expression of chalcone synthase (CHS) genes is highly dependent on light. 50 Long-distance transport from shoot to root of flavonoids has been confirmed.…”

A 16S rRNA amplicon approach to the structural and functional diversity of bacterial communities associated with horse gram crop for drought mitigation and sustainable productivity

“…Important features of Rhizobium along with non‐rhizobial endophytes such as Bacillus, Paenibacillus, Micromonospora, Flavobacterium, Pseudomonas, Paracoccus and Novosphingobium were highlighted in this study. These were found in all domains of horse gram with many interesting functional traits, such as nutrient acquisition (Dhole & Shelat, 2022), drought mitigation (Verma et al, 2021), secondary metabolite defence system against phytopathogens (Bag et al, 2022), and signalling mechanisms through root exudates (Chialva et al, 2022). Overall, we found that a persistent survival rate over spatial and temporal dynamic patterns existed among the diverse and abundant beneficial microbes with many functional traits present in all sequential ecological zones (soil, rhizosphere region, root nodules and seeds).…”

Understanding plant–microbe interaction of rice and soybean with two contrasting diazotrophic bacteria through comparative transcriptome analysis

“…Pathway analysis results showed that the major pathways involved within 5 days of inoculation were related to the biosynthesis of secondary metabolites, phenylpropanoids and flavonoids ( Thomas et al., 2019 ; Wiggins et al., 2022 ). Bag et al. (2022) suggested that secondary metabolites are crucial for plants’ adaptation to new changing environments and biotic and abiotic stress management.…”

“…Pathway analysis results showed that the major pathways involved within 5 days of inoculation were related to the biosynthesis of secondary metabolites, phenylpropanoids and flavonoids (Thomas et al, 2019;Wiggins et al, 2022). Bag et al (2022) suggested that secondary metabolites are crucial for plants' adaptation to new changing environments and biotic and abiotic stress management. Two pathways, viz., "Plant pathogen interaction" and "MAPK signaling," were specific to RG, whereas the pathways related to nitrogen metabolism and plant hormone signaling were specific to RB.…”