Author(s)

Kitti Wanlayaporn, Jetsada Authrapun, Apichat Vanavichit, Somvong Tragoonrung

Department of Agonomy, Faculty of Agriculture, Kasetsart University, Nakhon Pathom, Thailand.
Genome Institute, National Center for Genetic Engineering and Biotechnology, Pathum Thani, Thailand.
Interdisciplinary Graduate Program in Genetic Engineering, Kasetsart University, Bangkok, Thailand.

Southern corn rust is one of destructive diseases in maize caused by Puccinia polysora Undrew. A mapping population of tropical sweet corn recombinant inbred lines (RILs) derived from a cross between hA9104 and hA9035 inbred lines were set up to detect quantitative trait loci (QTLs) involved in partial resistance to southern corn rust. Eighty nine RILs were used to evaluate resistance levels using nine-point relative scale (1-9) at Sweet Seeds, Suwan Farm, Thailand include combined analysis. A genetic linkage map was constructed with 157 SSR markers, with a total length of 2123.1 cM, covering 10 chromosomes. Broad-sense heritability of individual location ranged from 0.76 and 0.82 and combined across locations was 0.87. Multiple QTL mapping (MQM) was applied for the identification of the QTLs. Fifteen QTLs were detected on chromosome 1, 2, 5, 6, 9 and 10 in both locations and combined across locations. QTLs on chromosome 1, 5 and 6 were contributed by alleles of resistant parent hA9104 while others were contributed by alleles from the susceptible parent, hA9035. Phenotypic variance of each QTL explained ranged from 6.1% to 41.8% with a total of 69.8% - 81.9%. QTL on chromosome 1, 6 and 10 were stable QTLs detected in both locations.

Sweet Corn; Southern Corn Rust; Partial Resistance; Quantitative Trait Loci (QTLs); Combined across Locations

K. Wanlayaporn, J. Authrapun, A. Vanavichit and S. Tragoonrung, "QTL Mapping for Partial Resistance to Southern Corn Rust Using RILs of Tropical Sweet Corn," American Journal of Plant Sciences, Vol. 4 No. 4, 2013, pp. 878-889. doi: 10.4236/ajps.2013.44108.