USING GENETIC DIVERSITY OF IMPROVE QUANTITATIVE DISEASE RESISTANCE AND AGRONOMIC TRAITS OF CORN
Location: Plant Science Research
Title: Mapping Disease Resistance QTL for Three Foliar Diseases of Maize in a RIL Population
Submitted to: Journal of Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 1, 2009
Publication Date: March 1, 2010
Citation: Zwonitzer, J., Coles, N., Krakowsky, M.D., Holland, J.B., McMullen, M.D., Pratt, R., Balint Kurti, P.J. 2010. Mapping Disease Resistance QTL for Three Foliar Diseases of Maize in a RIL Population. Journal of Phytopathology. 100:72-79.
Interpretive Summary: In this paper we identify regions of the genome conferring resistance to the corn diseases, northern corn leaf blight, southern leaf blight and grey leaf spot. We report evidence that some regions of the genome confer resistance to all three diseases.
Southern leaf blight (SLB), gray leaf spot (GLS), and northern leaf blight (NLB) are three important foliar diseases impacting maize production. The objectives of this study were to identify quantitative trait loci for disease resistance (dQTL) for resistance to these diseases in a maize recombinant inbred line (RIL) population, and to determine whether there was evidence for genes or loci conferring multiple disease resistance (MDR). The population of 109 RILs used in this study was derived from a cross between maize lines Ki14 and B73. Each disease was scored in separate trials. Nine, eight, and six dQTL were identified for SLB, GLS, and NLB, respectively. dQTL for all three diseases colocalized in bin 1.06, while dQTL colocalizing for two of the three diseases were identified in bins 1.08-1.09, 2.02/2.03, 3.04, 8.05, and 10.05. Highly significant correlations between the resistances to the three diseases were found. The highest correlation was identified between SLB and GLS resistance, (r=0.62). Identification of dQTL conferring resistance to more than one disease and the highly significant correlations observed suggest that MDR genes or loci are segregating within the Kb population.