Exploiting genetic diversity to achieve sustainable Sorghum Anthracnose disease management

Authors: Cuevas, Hugo; VERMERRIS, WILFRED - University Of Florida; Knoll, Joseph - Joe; Prom, Louis; WALLACE, JASON - University Of Georgia

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/18/2023
Publication Date: 6/5/2024
Citation: Cuevas, H.E., Vermerris, W., Knoll, J.E., Prom, L.K., Wallace, J.E. 2024. Exploiting genetic diversity to achieve sustainable Sorghum Anthracnose disease management. Meeting Abstract. Abstract.

Interpretive Summary:

Technical Abstract: The resilience and sustainability of sorghum is determined by the effective use of its large genetic diversity for tolerance to biotic and abiotic stresses. Host plant disease resistance offers the most sustainable control mechanism against biotic stresses. Anthracnose caused by Colletorichum sublineola is one of the most damaging sorghum fungal diseases worldwide, because it affects all aerial tissues of the plant, resulting in substantial yield losses. The identification of host plant resistance sources in genetically diverse sorghum germplasm is imperative to establish a long-term management control that increases the resilience and sustainability of sorghum. A subset of ~1,700 tropical accessions from the USDA-NPGS sorghum core collection were genetically characterized through genotyping-by-sequencing (GBS) to study its genetic diversity and population structure. The data are publicly accessible as a genomic resource. The anthracnose resistance response was evaluated in accessions from Ethiopia, Sudan, Yemen, West and Central Africa and sweet sorghums and identified many genetically diverse resistant accessions. Genome-wide association studies (GWAS) associated multiple genomic regions with the observed resistance response, but genomic regions on chromosomes 4, 5, 8 and 9 were controlling most of the phenotypic variation. In parallel, the sorghum association panel (SAP) and three recombinant inbred lines populations from the nested association mapping population (SC1103, SC265 and SC1345) were screened for anthracnose resistance. The GWAS and QTL studies identified multiple anthracnose resistance loci in this temperate-adapted germplasm. Comparative genome mapping analysis revealed that some of the resistance loci identified in tropical germplasm were introgressed into temperate-adapted germplasm. Therefore, the introgressions of new resistance sources from tropical germplasm must be strategically selected based on population structure and genetic profile. The combination of these different resistance sources will be the most effective strategies to manage anthracnose disease, thus making an important contribution to the resilience of sorghum exposed to new environmental conditions.