ARS | Publication request: Molecular Genetics of Fusarium Head Blight Susceptibility Associated with Chromosome 2a of Wild Emmer

Submitted to: Phytopathology
Publication Acceptance Date: July 31, 2004
Publication Date: July 31, 2004
Citation: Garvin, D.F., Stack, R.W. 2004. Molecular Genetics Of Fusarium Head Blight Susceptibility Associated With Chromosome 2a Of Wild Emmer [abstract]. Phytopathology. 94(supplement 6):s33.

Technical Abstract: The LDN(DIC) set of disomic substitution lines, in which chomosomes of durum wheat cv. Langdon (LDN) are replaced by corresponding ones from the wild emmer 'Israel A' (DIC), have been useful in locating genes for resistance to Fusarium head blight (FHB). The line LDN(DIC-2A) shows increased FHB, suggesting the presence of a susceptibility factor. A population of 95 recombinant inbred lines (RICL) from the cross LDN(DIC-2A) x LDN was screened for FHB resistance. DNA from the parents was isolated and screened with microsatellite markers to identify polymorphic loci. The FHB disease index of the RICL ranged from 18 to 95, with a mean of 61. The disease index for LDN and LDN(DIC-2A) were approximately 45 and 80, respectively. Molecular markers spanning over 100 cM of chromosome 2A were scored in the RICLs. QTL analysis revealed at least one region of chromosome 2A that was associated with increased susceptibility to FHB. Disease index means for individuals with alternate alleles at the microsatellite marker most strongly associated with FHB susceptibility differed by nearly 17% (71% vs 54%).