Genomic regions and novel sources associated with resistance to anthracnose in the Guatemalan climbing beans germplasm collection

Authors: MALDONADO-MOTA, CARLOS - Institute Of Agricultural Science And Technology (ICTA); MOGHADDAM, SAMIRA - Michigan State University; SCHRODER, STEPHAN - Bennekom, The Netherlands; Hurtado-Gonzales, Oscar; MCCLEAN, PHILLIP - North Dakota State University; PASCHE, JULIE - North Dakota State University; LAMPPA, ROBIN - North Dakota State University; Pastor Corrales, Marcial - Talo; TOBAR-PINON, MARIA - Institute Of Agricultural Science And Technology (ICTA); OSORNO, JUAN - North Dakota State University

Submitted to: Genetic Resources and Crop Evolution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/22/2020
Publication Date: 11/8/2020
Citation: Maldonado-Mota, C.R., Moghaddam, S.M., Schroder, S., Hurtado-Gonzales, O.P., Mcclean, P.E., Pasche, J., Lamppa, R., Pastor Corrales, M.A., Tobar-Pinon, M.G., Osorno, J.M. 2020. Genomic regions and novel sources associated with resistance to anthracnose in the Guatemalan climbing beans germplasm collection. Genetic Resources and Crop Evolution. 68:1073–1083. https://doi.org/10.1007/s10722-020-01050-y.
DOI: https://doi.org/10.1007/s10722-020-01050-y

Interpretive Summary: Anthracnose is a recurring disease that reduces yields of dry beans in the highlands of Guatemala. Planting resistant varieties is the most cost-effective way of managing this disease. Having multiple resistance genes is crucial for the development of common bean varieties with durable resistance to the anthracnose pathogen which is known to have populations comprised of many different virulent strains. In this study, 369 climbing bean accessions from the Guatemalan bean germplasm collection were inoculated under greenhouse conditions in Fargo, ND, with a virulent strain of the anthracnose pathogen that occurs in Central America, Mexico, and many others locations throughout the world. We found that 36 of the climbing accessions were resistant. A DNA-based study using 78,754 DNA markers was also conducted on the climbing beans. Several DNA regions associated with anthracnose resistance were identified on chromosomes Pv04 and Pv07 of common bean. Four candidate anthracnose resistance genes were also identified on both chromosomes. A future objective is to inoculate the resistant accessions with multiple virulent strains from Guatemala with the objective of identifying DNA regions that confer broad anthracnose resistance. These results can be used by scientists at universities, private institutions, and government agencies to develop anthracnose resistant beans that could benefit common bean producers and consumers.

Technical Abstract: The anthracnose disease caused by the fungal pathogen Colletotrichum lindemuthianum (Sacc and Magnus) Briosi and Cavara, is a disease that affects common bean (Phaseolus vulgaris L.) worldwide. Seed yield losses can reach up to 100% when infected seed is planted, and conditions favor the disease. A germplasm collection of climbing beans from Guatemala was evaluated in the greenhouse for their reaction to race 73 of C. lindemuthianum that occurs in many growing areas worldwide, was evaluated. This germplasm mostly represents the so-called race Guatemala. Approximately 10% of 369 climbing bean accessions showed no symptoms (score of 1 on a 1-9 anthracnose severity visual score scale). Genome wide association study (GWAS) results using 78,754 SNP markers indicated that genomic regions with resistance to race 73 of C. lindemuthianum exist in Pv04 and Pv07, which have been previously reported. We also report four candidate genes located on Pv04 and Pv07 suspected to be responsible for anthracnose resistance, based on their proximity to significantly associated SNP markers.