Role of flavins in the resistance of Sinorhizobium meliloti – alfalfa association to Aphanomyces root rot

CSANR Project 126

Status: Complete

Project Summary

Priority area:

Novel approaches to disease and fertility management that transcend traditional organic approaches and seek to exploit and integrate biological and chemical processes.

Flavins (riboflavin, FMN and FAD; vitamin B2) are bioactive molecules that have a beneficial effect on plant growth and soil quality. Recently we found that mutations in the riboflavin biosynthetic pathway affect the abundant flavin secretion by the nitrogen-fixing plant symbiont Sinorhizobium meliloti. We also have found that flavins play a critical role in the ability of S. meliloti to promote plant-host adaptation to environmental stresses – the features defining the efficiency of bacterial inoculums used as a part of Rhizobium-Legume crop system. However, the impact of rhizobia on the ability of the associated alfalfa to resist a pathogen attack or the effect of disease on symbiotic performance has not been evaluated. The goal of this research is to test the interaction of S. meliloti and Aphanomyces euteiches root rot on alfalfa. We speculate that the rhizobia will affect resistance/susceptibility of alfalfa and will evaluate the role of bacteria produced flavins on alfalfa resistance to the pathogen.


Annual Entries


Principal Investigator: Svetlana Yurgel
Grant Amount: $39000