|VAN SANFORD, DAVID|
Submitted to: National Fusarium Head Blight Forum Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/30/2007
Publication Date: 11/30/2007
Citation: Perugini, L., Sneller, C., Kolb, F., Van Sanford, D., Griffey, K., Ohm, H., Brown Guedira, G.L. 2007. Haplotype Structure and Genetic Diversity at Fusarium Head Blight Resistance QTLs in Soft Winter Wheat Germplasm. National Fusarium Head Blight Forum Proceedings.
Technical Abstract: Several quantitative trait loci (QTLs) for resistance to Fusarium head blight (FHB) have been mapped in wheat. Haplotyping strategies make use of previous QTL mapping and molecular marker information. In our study we selected markers reported to be near FHB resistance QTL mapped in Sumai 3, Wuhan 1 and Ernie to haplotype a large set of eastern SW wheat lines submitted by breeders The objectives of this research were to (1) determine the genetic relationship among soft winter (SW) wheat lines with native and exotic sources of resistance using simple sequence repeat (SSR) marker data, (2) compare the SSR marker haplotypes of SW wheat lines with those of Sumai 3, Wuhan 1, and Ernie at known FHB resistance QTLs, and (3) identify lines with novel sources of FHB resistance. Reaction of the SW entries evaluated was skewed toward resistance, with 59 lines classified as resistant, 116 moderately resistant, and 28 intermediate. Only 12 and 18 lines were considered moderately susceptible and susceptible, respectively. Of the resistant lines, 24 have exotic sources of resistance in the pedigree and the remaining resistant lines had only SW germplasm in their pedigrees. Entries were grouped into 16 clusters that were generally based on breeding program or geographic origin of lines. The Chinese wheat cultivars having the Fhb1 resistance gene were grouped separately from all other entries. The eight SW wheat entries in this study that have the Fhb1 resistance gene based on haplotype data were resistant in the field evaluation. The Xsts3B-256 and Xgwm533 markers can be clearly used to identify lines with the Fhb1 resistance gene. However, there is a need for fine mapping other regions in which FHB resistance QTLs have been located. This seems to be particularly important for resistance from Ernie as allele sizes of Ernie for markers in the 5A and 4BL QTL intervals are common among Eastern soft wheat germplasm. A number of SW wheat breeding lines did not share any haplotype at known QTLs evaluated in this study. These lines likely carry novel sources of FHB resistance.