Quantitative trait loci mapping for Gibberella ear rot resistance and associated agronomic traits using genotyping-by-sequencing in maize
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Unique and co-localized chromosomal regions affecting Gibberella ear rot disease resistance and correlated agronomic traits were identified in maize.
Dissecting the mechanisms underlying resistance to Gibberella ear rot (GER) disease in maize provides insight towards more informed breeding. To this goal, we evaluated 410 recombinant inbred lines (RIL) for GER resistance over three testing years using silk channel and kernel inoculation techniques. RILs were also evaluated for agronomic traits like days to silking, husk cover, and kernel drydown rate. The RILs showed significant genotypic differences for all traits with above average to high heritability estimates. Significant (P < 0.01) but weak genotypic correlations were observed between disease severity and agronomic traits, indicating the involvement of agronomic traits in disease resistance. Common QTLs were detected for GER resistance and kernel drydown rate, suggesting the existence of pleiotropic genes that could be exploited to improve both traits at the same time. The QTLs identified for silk and kernel resistance shared some common regions on chromosomes 1, 2, and 8 and also had some regions specific to each tissue on chromosomes 9 and 10. Thus, effective GER resistance breeding could be achieved by considering screening methods that allow exploitation of tissue-specific disease resistance mechanisms and include kernel drydown rate either in an index or as indirect selection criterion.
- Gabriel SB, Schaffner SF, Nguyen H, Moore JM, Roy J, Blumenstiel B, Higgins J, DeFelice M, Lachner A, Faggart M, Liu-Cordero SN, Rotimi C, Adeyemo A, Cooper R, Ward R, Lander ES, Daly MJ, Altshuler D (2002) The structure of haplotype blocks in the human genome. Science 296:2225–2229. doi:10.1126/science.1071220 CrossRefPubMedGoogle Scholar
- Hallauer AR, Carena M, Miranda Filho JB (2010) Quantitative genetics in maize breeding, 3rd edn. Iowa State University Press, AmesGoogle Scholar
- Löffler M, Kessel B, Ouzunova M, Miedaner T (2010) Population parameters for resistance to Fusarium graminearum and Fusarium verticillioides ear rot among large sets of early, mid-late and late maturing European maize (Zea mays L.) inbred lines. Theor Appl Genet 120:1053–1062. doi:10.1007/s00122-009-1233-9 CrossRefPubMedGoogle Scholar
- Martin M, Miedaner T, Schwegler DD, Kessel B, Ouzunova M, Dhillon BS, Schipprack W, Utz HF, Melchinger AE (2012) Comparative quantitative trait loci mapping for Gibberella ear rot resistance and reduced deoxynivalenol contamination across connected maize populations. Crop Sci 52:32–43. doi:10.2135/cropsci2011.04.0214 CrossRefGoogle Scholar
- Reid LM, Mather DE, Bolton AT, Hamilton RI (1994) Evidence for a gene for silk resistance to Fusarium graminearum Schw. ear rot of maize. J Hered 85:118–121Google Scholar
- Reid LM, Woldemariam T, Zhu X, Stewart DW, Schaafsma AW (2002) Effect of inoculation time and point of entry on disease severity in Fusarium graminearum, Fusarium verticillioides, or Fusarium subglutinans inoculated maize ears. Can J Plant Pathol 24:162–167. doi:10.1080/07060660309506991 CrossRefGoogle Scholar
- Reid LM, Zhu X, Morrison MJ, Woldemariam T, Voloaca C, Wu J, Xiang K (2010) A non-destructive method for measuring maize kernel moisture in a breeding program. Maydica 55:163–171Google Scholar
- Swarts K, Li H, Navarro JAR, An D, Romay MC, Hearne S, Acharya C, Glaubitz JC, Mitchell S, Elshire RJ, Buckler ES, Bradbury PJ (2014) Novel methods to optimize genotypic imputation for low-coverage, next-generation sequence data in crop plants. Plant Genome. doi:10.3835/plantgenome2014.05.0023 Google Scholar