Project Number: 1275-22000-261-01
Project Type: Specific Cooperative Agreement

Start Date: Aug 11, 2006
End Date: May 17, 2009

Objective:
Conduct research to reduce the genetic vulnerability in common bean to highly variable pathogens by incorporating new genes for disease resistance with special consideration for the hyper variable bean rust pathogen. The emphasis will be on, but not limited to, genes from the under-utilized Andean gene pool, wild and landrace andean and Middle American Beans.

Approach:
Field rust collection of the rust pathogen will be used to monitor the virulence diversity of Uromyces appendiculatus. This diversity will be characterized by inoculating rust pathogen strains on a set of differential bean cultivars. Virulence analysis results will be used to construct a phylogenetic tree that determines relationship among strains. Beans containing both characterized and uncharacterized rust resistance genes and released bean germplasm lines having various rust resistance gene combinations will be challenged with newly identified strain of the rust pathogen. The genetic diversity of the strains will be explored with molecular markers. Clusters based on molecular markers will be compared with those generated by virulence analysis for insights into the evolution of the rust pathogen with beans. Classical genetics methods will be used to study the mode of inheritance of new rust resistance genes.