Fusarium head blight resistance QTL in an elite doubled haploid winter wheat cross 32C*17/Peregrine.
Lin Y, Brule-Babel A, McCartney C, Loewen M, Humphreys G (2018) Fusarium head blight resistance QTL in an elite doubled haploid winter wheat cross 32C*17/Peregrine. Poster and abstract presented at 9th Canadian Fusarium Workshop, Nov. 19-22, 2018 in Winnipeg, MB
Resistance to Fusarium head blight (FHB) is complex and involves multiple genes with relatively small effects. The breeding line 32C*17 did not carry the widely known Fhb genes (Fhb1, Fhb2, and Fhb5) but still showed strong FHB resistance under severe disease pressure in both Canada and Germany. A doubled haploid population was generated from the cross between 32C*17 and the cultivar Peregrine with intermediate FHB resistance. Disease incidence (Inc), severity, Fusarium damaged kernels and deoxynivalenol (DON) were collected from six site-years of field tests and one year of greenhouse testing. Genotyping was done with the 90K wheat Illumina Infinium iSelect SNP array platform. A linkage map with the total length of 1827.56cM was generated and covered approximately 80% of the wheat genome. Transgressive segregation was observed for all FHB traits measured. Several FHB QTLs were detected, but were not consistently shown through all site years. The 32C*17 alleles for QTL identified on chromosomes 6D and 4D reduced Inc and DON. The 4D QTL was 10-12 cM (450,358,490 bp ) away from the Rht-D1 locus, thus this 4D FHB resistance was not directly affected by the Rht-D1 locus. Peregrine showed intermediate field severity (32.6%) and high greenhouse severity (75.3%), but it still contributed a Type II resistance QTL on the chromosome 3A in both field and greenhouse tests. Although the parents were polymorphic for Fhb2, Qfhs.ifaSA (5A) and Qfhi.nauSA (5A), no FHB QTL were detected in this region. This study revealed that 32C*17 mainly contributed Type I FHB resistance.