|Holland, Jim - Jim|
Submitted to: Genetics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/21/2007
Publication Date: 5/1/2007
Citation: Balint Kurti, P.J., Zwonitzer, J., Wisser, R., Oropeza-Rosas, M., Holland, J.B., Szalma, S., Carson, M.L. 2007. Precise mapping of Quantitative Trait Loci for Resistance to Southern Leaf Blight, caused by Cochliobolus heterostrophus race O, using an Advanced Intercross Maize Population. Genetics. 176:645-657. Interpretive Summary: We have used two different populations to map genes that confer substantial levels of resistance to Southern leaf blight of corn and have shown that a particular population (the IBM population) allows the mapping of these genes with an unprecedented level of precision. We have shown that most of these genes work well under widely different levels of disease pressure.
Technical Abstract: The IBM population, an advanced intercross recombinant inbred line population derived from a cross between the maize lines Mo17 (resistant) and B73 (susceptible), was evaluated in four environments for resistance to southern leaf blight (SLB) disease caused by Cochliobolus heterostrophus race O. Two environments were artificially inoculated, while two were not inoculated and consequently had substantially lower disease pressure. Four common SLB resistance QTL were identified in all environments; two in bin 3.04 and one each in bins 1.10 and 8.02/3. There was no significant correlation between disease resistance and days to anthesis. A direct comparison was made between SLB QTL detected in two populations, independently derived from the same parental cross; the IBM advanced intercross population and a conventional RIL population. The same major QTL for SLB resistance were detected in both populations, with the IBM providing between five and fifty times greater mapping precision.