Location: Plant Science ResearchTitle: Genome-wide association study of popping expansion in tropical popcorn and field corn germplasm
|CAMARGO SENHORINHO, HENRIQUE - Universidade Estadual De Maringá|
|DACAL COAN, MARLON - Universidade Estadual De Maringá|
|MARINO, THIAGO - North Carolina State University|
|KUKI, MAURICIO - Universidade Estadual De Maringá|
|BARTH PINTO, RONALD - Universidade Estadual De Maringá|
|SCAPIM, CARLOS - Universidade Estadual De Maringá|
|Holland, Jim - Jim|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2019
Publication Date: 9/1/2019
Citation: Camargo Senhorinho, H.J., Dacal Coan, M.M., Marino, T.P., Kuki, M.C., Barth Pinto, R.J., Scapim, C.A., Holland, J.B. 2019. Genome-wide association study of popping expansion in tropical popcorn and field corn germplasm. Crop Science. 59:2007–2019.
Interpretive Summary: The most important characteristic of popcorn that determines its economic value is its popping expansion. Field corns that do not pop or only pop a small amount have low popping expansion values. High quality popcorn seeds, in contrast, have large values for popping expansion. We evaluated 186 inbred lines of maize, including both field and popcorn types for popping expansion, and used high density genome-wide markers to identify a small number of genetic variations that are associated with popping expansion. These markers can be used in breeding programs where the yield of popcorns is increased while maintaining good popping expansion.
Technical Abstract: Popcorn is a popular snack food with higher grain value compared to ‘field corn’ maize. In general, popcorn germplasm is less improved than common maize cultivars, with less favorable agronomic performance and greater susceptibility to pests, diseases, and lodging, especially in tropical environments. One approach to expanding and improving popcorn germplasm is to introduce favorable alleles for agronomic performance from field corn. If markers tagging quantitative trait loci (QTL) associated with popping expansion could be identified, they selected with markers to maintain popping expansion in breeding populations derived from crosses between field and popcorn. The objectives of this study were to identify single nucleotide polymorphism (SNP) markers and putative candidate genes associated with higher popping expansion in a diverse sample of popcorn and field corns relevant to Brazilian breeding programs. We applied a comprehensive genome wide association study (GWAS) for popping expansion, using 165,089 SNP markers in 183 inbred lines with two years of trial data. Four SNPs were significantly associated with popping expansion, some of which were colocalized to previously reported meta-QTLs, and others that were novel. Annotated genes closely linked to the associated SNPs were identified with functions related with starch content, which plays an important role in popping expansion quality. If these associations can be validated independently, they can be useful for breeders to select agronomically superior genotypes with greater popping expansion.