New Andean source of resistance to anthracnose and angular leaf spot: fine-mapping of disease-resistance genes in California Dark Red Kidney common bean cultivar

Authors: GONCALVES-VIDIGAL, M - Universidade Estadual De Maringá; GILIO, T - Universidade Estadual De Maringá; VALENTINI, G - Universidade Estadual De Maringá; VAZ-BISNETA, M - Universidade Estadual De Maringá; VIDIGAL FILHO, P - Universidade Estadual De Maringá; Song, Qijian; OBLESSUC, P - University Of California; MELOTTO, M - University Of California

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/11/2020
Publication Date: 6/29/2020
Citation: Goncalves-Vidigal, M.C., Gilio, T., Valentini, G., Vaz-Bisneta, M., Vidigal Filho, P.S., Song, Q., Oblessuc, P.R., Melotto, M. 2020. New Andean source of resistance to anthracnose and angular leaf spot: fine-mapping of disease-resistance genes in California Dark Red Kidney common bean cultivar. PLoS One. 15(6):e0235215. https://doi.org/10.1371/journal.pone.0235215.
DOI: https://doi.org/10.1371/journal.pone.0235215

Interpretive Summary: Anthracnose (ANT) and angular leaf spot (ALS) are devastating diseases of common bean around the world. Breeders are constantly searching for new genes with broad-spectrum resistance against the two diseases. Previous studies reported that Andean common bean cultivar California Dark Red Kidney was resistant to races of ANT and ALS found in Brazil, Argentina, Colombia, Central America, Africa and Europe. In this study, we mapped the DNA of California Dark Red Kidney to find resistance genes. We observed that the resistance to both ANT and ALS in California Dark Red Kidney was conferred by a novel, single dominant gene. We mapped the gene to a 33 kilobase DNA region at the end of chromosome 1 and developed markers to tag the resistance gene. The information from this study will greatly facilitate breeding this gene into beans that are currently susceptible to ANT and ALS. Scientists and breeders working in industry, academics and the government can use this information to improve the common bean.

Technical Abstract: Anthracnose (ANT) and angular leaf spot (ALS) caused by Colletotrichum lindemuthianum and Anthracnose (ANT) and angular leaf spot (ALS) caused by Colletotrichum lindemuthianum and Pseudocercospora griseola, respectively, are devastating diseases of common bean around the world. Therefore, breeders are constantly searching for new genes with broad-spectrum resistance against ANT and ALS. This study aimed to characterize the genetic resistance of California Dark Red Kidney (CDRK) to C. lindemuthianum races 73, 2047, and 3481 and P. griseola race 63-39 through inheritance, allelism testing, and molecular analyses. Genetic analysis of response to ANT and ALS in recombinant inbred lines (RILs) from a CDRK × Yolano cross(CY)showed that the resistance of CDRK cultivar is conferred by a single dominant loci, which we named CoPv01CDRK/PhgPv01CDRK. Allelism tests performed with race 3481 showed that the resistance gene in CDRK is independent of the Co-1 and Co-AC. We conducted co-segregation analysis based on genotypes of 110 CY RILs and phenotypes of the RILs in response to different races of the ANT and ALS pathogens. The results revealed that CoPv01CDRK and PhgPv01CDRK are coinherited, conferring resistance to all races. Genetic mapping of the CY population placed the CoPv01CDRK/PhgPv01CDRK loci in a 245 Kb genomic region at the end of Pv01. By genotyping 19 RILs from the CY population using three additional markers, we fine-mapped the CoPv01CDRK/PhgPv01CDRK loci to a smaller genomic region of 33 Kb. This 33 Kb region harbors five predicted genes based on the common bean reference genome. These results can be applied in breeding programs to develop bean cultivars with ANT and ALS resistance using marker-assisted selection.