Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/1/2003
Publication Date: 11/1/2003
Citation: Garvin D.F., Hansen, J.M., Stack, R.W. 2003. Genetic characterization of a scab resistance suppressor from wild emmer [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. CD-ROM. Paper No. 621.
Technical Abstract: Fusarium head blight (FHB) is a major disease of wheat in many regions of the world. Recently Stack et al. (2002) provided evidence for the existence that chromosome 2A from wild emmer line 'Israel A' increases FHB susceptibility. The genetic basis of this phenomenon is now being investigated in further detail. Results of disease evaluations of hybrids from a cross between the durum wheat line 'Langdon' and a Langdon-Israel A chromosome 2A substitution line suggests that the extreme FHB susceptibility conferred by Israel A chromosome 2A is additive in nature. In contrast, a major FHB resistance QTL on chromosome 3A of Israel A behaved in a dominant fashion when similarly tested. The hybrids from a cross between the durum-Israel A 2A and 3A chromosome substitution lines exhibited FHB severity intermediate to these two lines, indicating that gene(s) on chromosome 2A suppress the chromosome 3A FHB resistance QTL. Analysis of FHB severity in individuals from a segregating population derived from this same cross revealed that individuals presumed to have the FHB resistance QTL exhibited a FHB severity frequency distribution similar to that expected if a single additive genetic factor conditioning FHB susceptibility was segregating in these individuals. Molecular mapping of the regions of Israel A chromosome 2A that are responsible for increased FHB susceptibility is being pursued.