Publication:

It's not you, it's me: Medicago truncatula efd-1 mutant phenotype depends on rhizobium symbiont

The work by Jardinaud et al. (2022a) illustrates the need to reconsider the identification of genes with a functional role in symbiosis when using a model system in which nodule development and plant growth are constrained due to a less efficient N-fixer. The influence of genotype-genotype interactions on the outcome of the legume-rhizobium symbiosis is a growing field of research (Cangioli et al. 2022). It is worth noting that this regulation is clearly bidirectional: not only the rhizobium strain influences the plant phenotype but also the other way around. One fine example of the latter is the hostdependent regulation of symbiotic hydrogenase expression in Rhizobium leguminosarum bv. viciae (Brito et al. 2008). Identifying the plant and bacterial factors that control the efficiency of these symbiotic systems is an exciting challenge that lies ahead.