204
in tetraploid wheat maps to chromosome 3AS and is not homologous to the locus
on chromosome 3BS of Sumai3 (Chen et al. 2007 ). A novel FHB resistance QTL
was mapped to chromosome 7A in tetraploid wheat (Kumar et al. 2007 ). This is
only the second major FHB QTL mapped in tetraploid wheat. Its R^2 value was 19
%. Tetraploid wheat accessions from Tunisia were a source of additional resistance
to FHB. Twenty such accessions were haplotyped with markers for known FHB
loci (Huhn et al. 2012 ). Based on these results there were indications that those
accessions likely carry novel sources of Type II FHB resistance. Moderate FHB
resistance was detected in one accession of T. carthlicum (4×), designated as
“Blackbird” (Fig. 8.3 ). This accession was crossed to Strongfi eld and a DH map-
ping population of 85 lines was produced (Somers et al. 2006 ; Han and Fedak
2003 ). Two QTL for FHB resistance were reported in this population. A QTL on
chromosome 6BS was derived from Blackbird and one on 2BL from Strongfi eld
(Fig. 8.4 ). The QTL on chromosome 6BS was coincident with the known FHB
resistance QTL Fhb2 derived from Sumai3. Two other loci located on chromo-
somes 5AS and 2AL had on epistatic effect on the locus on 6BS (Singh et al. 2008 ).
Three mapping populations derived from crosses of a resistant T. dicoccum donor
line with three Austrian recipient cultivars were produced (Buerstmayr et al. 2012 ).
Resistant QTL were detected on chromosomes 3B, 4B, 6A, 6B, and 7B; all QTL
except for 3B were contributed by T. dicoccum. All QTL except for 6A mapped to
genomic regions where FHB QTL have previously been reported in hexaploid
Fig. 8.3 FHB resistance
expressed on spike of
strain “Blackbird” of T.
carthlicum at 21 days after
inoculation
G. Fedak