Biotic Interactions in the Rhizosphere: A Diverse Cooperative Enterprise for Plant Productivity

Abstract

Microbes and plants have evolved biochemical mechanisms to communicate with each other. The molecules responsible for such communication are secreted during beneficial or harmful interactions. Hundreds of these molecules secreted into the rhizosphere have been identified, and their functions are being studied in order to understand the mechanisms of interaction and communication among the different members of the rhizosphere community. The importance of root and microbe secretion to the underground habitat in improving crop productivity is increasingly recognized, with the discovery and characterization of new secreting compounds found in the rhizosphere. Different omic approaches, such as genomics, transcriptomics, proteomics, and metabolomics, have expanded our understanding of the first signals between microbes and plants. In this review, we highlight the more recent discoveries related to molecules secreted into the rhizosphere and how they affect plant productivity, either negatively or positively. In addition, we include a survey of novel approaches to studying the rhizosphere and emerging opportunities to direct future studies.

Salinity tolerance of crops – what is the cost?

“…Rhizospheric fungi and plant growth-promoting rhizobacteria (PGPR) can increase plant yield under stressed and nonstressed conditions (De-la-Pena & Loyola-Vargas, 2014;Nadeem et al, 2014). Salt-tolerant PGPR populations can reduce Na + content of shoots, increase the expression of stress-responsive transcription factors, induce greater proline synthesis, enhance ROS scavenging and improve plant biomass under salinity stress (De-la-Pena & Loyola-Vargas, 2014;Nadeem et al, 2014). Arbuscular mycorrhizal fungal colonization of roots can improve plant salt tolerance by increasing water acquisition and shoot K + whilst decreasing shoot Na + concentration (Auge et al, 2014).…”

A Proteomic Approach Suggests Unbalanced Proteasome Functioning Induced by the Growth-Promoting Bacterium Kosakonia radicincitans in Arabidopsis

“…In general, the physiological alterations within the plant and the emerging phytostimulation provoked by PGPB are assigned to bacterial nitrogen fixation, increased nutrient uptake, production of plant hormones and modulation of plant development (van Loon, 2007; De-la-Pena and Loyola-Vargas, 2014). The plant root system has a vital role in water and nutrient acquisition, as well as in signaling of environmental cues and adaptation to altered conditions in the rhizosphere.…”

Integrated analysis of root microbiomes of soybean and wheat from agricultural fields

“…Other recent studies have focused on rhizospheric soil microbiota of soybean ( Glycine max ) in Amazon field environments and corn ( Zea mays) in production fields in the United States1819. Regardless of these foundational works, we know little about root microbiomes from crops and further research on root and rhizospheric soil microbiomes of commercial crops and non-model plants is currently highly required122021. For instance, no research to-date has explored root-associated microbiomes of wheat ( Triticum aestivum ) and soybean in field conditions using high-throughput sequencing techniques, despite the fact that these are the fourth and ninth most produced crops in the world22.…”