Genomic regions for resistance to fungi and viruses in maize

ROSSI, E.; RUIZ, M.; RUEDA CALDERÓN, A.; BRUNO, C.; BONAMICO, N.; BALZARINI, M.

Congreso; XXXVI Reunión Científica Anual de la Sociedad de Biología de Cuyo; 2018

Discovering communalities among studies reporting quantitative trait loci (QTL) for maize diseases resistance is crucial. First, we performed a literature systematic review to search published QTL for maize disease resistance by searching multiple databases with the term ("Zea mays" or maize or corn), ((resistance or tolerance) and "disease"), (QTL or loci or "Quantitative Trait Loci"). A total of 110 studies containing QTL information related to fungi and virus resistance were found. Second, we performed a meta-analysis aimed at identifying genomic regions carrying major-effect QTL for resistance to fungal and viral diseases. For each chromosome, reported QTL were counted, and a global odd ratio of carrying major effect loci was calculated by averaging findings across studies. Results show that the greatest number of QTL was reported in chromosome 1, but the odds of finding major-effect loci for fungus and virus resistance in chromosome 10 were twice as high as the odds of finding those main loci in the rest of the genome. The major-effect QTL reported for resistance to fungal diseases were not located on the same chromosomes as those with virus resistance, except for chromosome 10. There was no agreement among studies in the occurrence of major-effect loci on chromosome 3 and 8. Bins 1.03, 1.04, 1.05, 1.06, 1.10, 2.04, 2.07, 5.03, 6.02 and 10.06 in chromosome 1, 2, 5, 6 and 10 were recognized as genomic regions where major-effect QTL are located. Our results summarize and confirm published findings about key genomic regions for maize molecular breeding against diseases that can cause significant yield losses.