Investigating Escape from Adaptive conflict in the Legume Medicago truncatula

Trade-offs between genetically correlated traits cause significant evolutionary consequences. One example of an agriculturally and ecologically important trade-off exists between the ability for the legume plant Medicago truncatula to attract nitrogen-fixing rhizobia and to repel parasitic root-knot nematodes. In this study, I conducted a greenhouse experiment to examine one Medicago truncatula genotype that appears to have escaped this genetic conflict. I also included 17 closely grouped genotypes (based on phylogenetic distance) to see if I could identify others that behave similarly. While I was not able to replicate a positive correlation between susceptibility to rhizobia and nematodes, I did confirm the phenotype of the previously identified outlier genotype. Finally, I identified one other genotype that formed significantly more interactions with beneficial rhizobia while forming significantly less interactions with parasiti nematodes. My findings provide some very exciting avenues to pursue future research in identifying the genetic underpinnings of this interesting phenotype.