Characterization and mapping of a rust resistance gene in the common bean landrace G19833

Authors: VALENTINI, GISELI - North Dakota State University; PASTOR-CORRALES, MARCIAL - Retired ARS Employee; HURTADO-GONZALES, OSCAR - Animal And Plant Health Inspection Service (APHIS); XAVIER, LARISSA - Orise Fellow; GILL, UPINDER - North Dakota State University; Song, Qijian

Submitted to: G3: Genes, Genomes, Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/30/2025
Publication Date: 7/21/2025
Citation: Valentini, G., Pastor-Corrales, M., Hurtado-Gonzales, O., Xavier, L., Gill, U., Song, Q. 2025. Characterization and mapping of a rust resistance gene in the common bean landrace G19833. G3: Genes, Genomes, Genetics. https://doi.org/10.1093/g3journal/jkaf168.
DOI: https://doi.org/10.1093/g3journal/jkaf168

Interpretive Summary: Common bean is an important food source globally, especially in Latin America and Africa, where it provides nutrition to millions of people. However, disease caused by fungal rust threatens bean production, especially under warm, wet conditions. Controlling rust diseases is challenging due to the pathogen's high genetic diversity and ability to evolve resistance-damaging strains. To address this, the researchers at USDA and North Dakota State University focused on G19833, a bean variety from Peru known for its strong resistance to multiple rust pathogens. The team aimed to identify the genetic basis of G19833 resistance. By combining phenotyping and genotyping of a large, segregated population, they identified a dominant gene conferring resistance to four major rust pathogens. The gene was mapped to a specific region on chromosome Pv04 that is rich in disease resistance genes. In depth molecular analyses further revealed several highly expressed resistance-related genes, providing insights into the defense mechanisms of G19833. Information from this study will enable breeders to incorporate the gene into new varieties and confer long-lasting resistance to multiple rust pathogens, which will reduce reliance on chemical controls, lower costs and environmental impacts while ensuring stable yield.

Technical Abstract: The Andean common bean landrace, G19833 exhibits broad and effective resistance to many virulence races of Uromyces appendiculatus, the fungal pathogen that causes the rust disease of common bean. The comprehensive resistance spectrum in G19833 enables the development of common bean cultivars with extensive resistance to the bean rust pathogen. In this study, we combined phenotyping, high throughput genotyping and large segregating populations to characterize and map the rust resistance gene present in G19833. Our results revealed one single dominant gene in G19833 conditioning resistance to the races 16-1 (52), 31-1 (53), 30-1 (55), and 37-1 (84) of U. appendiculatus. Using 650 F2 and 1,977 F3 plants from the G19833 × Olathe cross enable mapping the rust resistance gene to a 747 kb genomic region on chromosome Pv04. This region is characterized by low recombination and is known to contain several disease resistance genes, including those associated with rust resistance. We performed in silico gene expression analysis using RNA-seq data from G19833 to identify functional nucleotide-binding sites with leucine-rich repeats (NLRs). Our analysis revealed that some NLR genes were highly expressed across all 11 plant tissues examined, while others showed higher expression on specific tissues. These insights enhance our understanding of rust resistance in common beans and will facilitate the development of cultivars with durable rust resistance.