Association mapping of genomic regions for resistance to anthracnose disease in sorghum association panel

Abstract

Sorghum [Sorghum bicolor (L.) Moench] is an important cereal crop for dryland areas in the world. The crop is constrained by several biotic and abiotic factors that reduce the productivity by up to 100% under severe conditions. The objective of this study was to determine the response of sorghum genotypes to anthracnose disease and identify genomic regions associated with resistance to anthracnose disease in sorghum association panel (SAP) collection. A total of 340 genotypes were screened in the field for resistance to anthracnose under natural infestation and 10 anthracnose resistant genotypes were identified. SAP_PI656036 was the most resistant and high yielding genotype. To facilitate gene discovery and molecular breeding in sorghum, approximately 265,000 single nucleotide polymorphisms (SNPs) in 274 worldwide accessions were characterized. Genome-wide association study was performed for anthracnose severity scores at ANT-70, ANT-77, ANT-84, ANT-91 and SAM in different locations. The GWAS analysis mapped 5 significant SNPs associated with several loci on Chr01, Chr02, Chr06 and Chr08 for resistance to anthracnose. The genome-wide SNP markers identified in this study can provide a basis for crop improvement through marker-assisted breeding and genomic selection. Furthermore, markers identified in this study could be converted into Kompetitive Allele Specific PCR (KASP) markers to support marker-assisted breeding for resistance to sorghum anthracnose.