Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/15/2005
Publication Date: 1/14/2006
Citation: Chen, X., Faris, J.D., Jinguo, H., Stack, R., Adhikari, T., Kianian, S., Cai, X. 2006. Saturation mapping of the major FHB resistance QTL Qfhs.ndsu-3AS in tetraploid wheat. Plant and Animal Genome XIV Conference Abstracts, P291.
Technical Abstract: Fusarium head blight (FHB) is a serious disease of durum wheat (Triticum turgidum L. var. durum, 2n=4x=28, genomes AABB) worldwide. Sources of effective resistance have not been identified in durum wheat. One source of resistance is the wild tetraploid, T. turgidum subsp. dicoccoides. In previous work, a population of 83 recombinant inbred chromosome lines (RICLs) derived from a cross between Langdon (LDN) and a disomic LDN-T. dicoccoides (LDN-DIC) chromosome 3A substitution line was used to construct a genetic map for chromosome 3A, and an FHB resistance QTL designated Qfhs.ndsu-3AS was identified. Here, we used SSR, STS, TRAP and EST-derived markers to saturate the genomic region containing the QTL. The entire population was screened for reaction to FHB in two additional greenhouse experiments, and subsequent data analysis indicated that Qfhs.ndsu-3AS now explains 55% of the phenotypic variation. Two co-dominant PCR-based markers that flank the QTL region were used to screen 545 F2 plants derived from a cross between LDN and the RICL LDN-DIC 3A-72, which harbors the FHB resistance QTL on a small fragment derived from T. dicoccoides. Using the flanking markers we identified 117 recombinants, which were further used for high resolution mapping of the QTL region. Comparative mapping indicated that Qfhs.ndsu-3AS is not homoeologous to Qfhs.ndsu-3BS, a major FHB QTL derived from the common wheat cultivar Sumai 3.