0 avis
Symbiotic stimulation of root development in Medicago truncatula through the eyes of GWAS
Archive ouverte
Edité par CCSD -
International audience. Medicago truncatula is a model legume able to establish two types of root endosymbioses: root nodule symbiosis (nodulation) with nitrogen fixing rhizobia and arbuscular mycorrhizal symbiosis with some Glomeromycota fungi. These two types of root endosymbioses are beneficial for nitrogen and phosphate nutrition of the plant, respectively. Interestingly, establishment of these two endosymbioses requires a common set of plant genes, so called “Common symbiosis signaling pathway” (CSSP) and these two types of symbionts produce similar symbiotic signals called Lipo-chitooligosaccharides (LCOs). On top of their role in the establishment of root endosymbiosis, purified LCOs also stimulate root branching.Exploiting natural diversity together with genome wide association study (GWAS) is a powerful approach to explore trait architecture to identify gene polymorphisms associated with plant adaptation. This strategy was previously applied to identify nodulation-related loci in Medicago truncatula. Here, we have used GWAS together with a newly developed local score test to discover genomic regions including SNPs associated with rhizobial (Nod) or mycorrhizal (Myc) LCO stimulation of lateral root development in 173 natural accessions of Medicago truncatula. Heritability was higher for Nod-LCO than Myc-LCO. Using different phenotypic parameters and the local score approach, we could identify 123 loci for Nod-LCO and 71 for Myc-LCO stimulation. The loci identified suggest strikingly different mechanisms possibly underlying lateral root stimulation by these two closely related molecules that I will discuss here.
Consulter en ligne
Suggestions
Du même auteur
