Submitted to: International Rice Genetics Symposium
Publication Type: Proceedings
Publication Acceptance Date: 9/15/2005
Publication Date: 11/1/2005
Citation: Pinson, S.R., Hulbert, S., Liu, K., Nelson, J.C. 2005. Correlation between QTLs conferring resistance to four different diseases with each other and with RGAs identifies key regions for future research [abstract]. 5th International Rice Genetics Symposium, Manila, Philippines. p. 95.
Technical Abstract: The Lemont/TeQing RIL population is among the most studied rice gene-mapping populations available today, with 400+ QTL reported to date. Because these QTL were all mapped using the same population, their genetic locations and effects can be compared directly, without inexact interpolation between different genotypes and marker maps. QTL conferring resistance to four different diseases have been mapped in this population, including sheath blight (SB), blast, bacterial leaf blight (BLB), and bacterial panicle blight (BPB). By comparing the various disease resistance QTL with each other, with QTL for confounding traits such as plant height and heading time, and with resistance gene analogues (RGAs), we have identified four chromosomal regions of particular interest for further characterization of the genes/sequence. While no chromosomal regions were associated with resistance to all four diseases, four regions contain resistance QTLs for three diseases. The centromeric region of chromosome 12 contains resistance QTL for SB, blast and BLB and is known to contain a cluster of major blast resistance genes. The centromeric region of chromosome 3, and chromosome 4 from upper tip to its centromere (tip to RG1094e) contain QTL for SB, blast and BLB. No major resistance genes but several RGA’s map to these same regions. A BPB QTL maps just below this centromere, where an identically located heading date QTL and few RGAs reside. Chromosome 8 between C825x and RZ323 contains QTL for SB, BLB and BPB. Several RGA’s map to this region, but so do loci with large effect on height and heading.