Bean rust, caused by uromyces appendiculatus, is a significant disease of dry and snap beans (phaseolus vulgaris) in the united states

North Dakota State University received a $744,729 Project Grant from the U.S. Department of Agriculture's National Institute of Food and Agriculture (NIFA) under the Agriculture and Food Research Initiative (AFRI), CFDA 10.310, awarded on August 1, 2025, with completion targeted for July 31, 2028. The award funds research to characterize bean rust disease caused by Uromyces appendiculatus, a significant threat to domestic dry and snap bean production. The project will employ traditional phenotyping and genomic analysis to examine the extensive population diversity of U. appendiculatus isolates that have evolved in the United States over the past three decades, with comparative analysis of global isolates from three additional continents to assess origin, evolution, and spread patterns.

The primary deliverable is the development of phased chromosome-scale reference genome assemblies for two U. appendiculatus isolates representing distinct Mesoamerican and Andean gene pools. These genomic resources will facilitate current and future scientific studies on the pathogen and support the development of improved rust resistance breeding strategies. By generating new insights into the genetic diversity and evolutionary dynamics of this wind-borne fungal pathogen, the project aims to strengthen U.S. and global food security in common bean production.

Despite numerous advancements in resistance breeding, U. Appendiculatus continues to evolve, posing a significant threat to bean production. The wind-borne spores of U. Appendiculatus can travel across continents to cause disease epidemics. The proposed research aims to address these challenges by unraveling the U. Appendiculatus extensive population diversity that originated in the US over the past three decades using traditional phenotyping and genomics. The US isolates will be compared to global isolates collected from three additional continents at genomic levels to study origin, evolution, and spread. This project will also develop phased chromosome-scale reference genome assemblies of two U. Appendiculatus isolates representing mesoamerican and andean gene pools to facilitate current and future genomic studies. The project aims to safeguard the US and global food security by generating new insights to mitigate threats to common bean production.