Compatibility between Legumes and Rhizobia for the Establishment of a Successful Nitrogen-Fixing Symbiosis

CLUA J; RODA C; ZANETTI ME; BLANCO FA

Genes

MDPI AG

Año: 2018

The root nodule symbiosis established between legumes and rhizobia is an exquisitebiological interaction responsible for fixing a significant amount of nitrogen in terrestrialecosystems. The success of this interaction depends on the recognition of the right partner by theplant within the richest microbial ecosystems on Earth, the soil. Recent metagenomic studies of thesoil biome have revealed its complexity, which includes microorganisms that affect plant fitnessand growth in a beneficial, harmful, or neutral manner. In this complex scenario, understandingthe molecular mechanisms by which legumes recognize and discriminate rhizobia frompathogens, but also between distinct rhizobia species and strains that differ in their symbioticperformance, is a considerable challenge. In this work, we will review how plants are able torecognize and select symbiotic partners from a vast diversity of surrounding bacteria. We will alsoanalyze recent advances that contribute to understand changes in plant gene expression associatedwith the outcome of the symbiotic interaction. These aspects of nitrogen-fixing symbiosis shouldcontribute to translate the knowledge generated in basic laboratory research into biotechnologicaladvances to improve the efficiency of the nitrogen-fixing symbiosis in agronomic systems.