Canadian heritage wheat variety alleles of flowering and plant height pathway genes associated with low fusarium head blight

Citation

Dhariwal, R., Henriquez, M.A., Hiebert, C., McCartney, C., Graf, R., Randhawa, H. 2018. Canadian heritage wheat variety alleles of flowering and plant height pathway genes associated with low fusarium head blight. 9th Canadian Workshop on FHB & 4th Canadian Wheat Symposium, November 19–22, 2018 Winnipeg, Manitoba.

Résumé

Fusarium head blight (FHB), caused by mycotoxin-producing Fusarium species, is a devastating disease
that reduces yield, quality and marketability of wheat grains. Presence of mycotoxins e.g. deoxynivalenol
(DON) in the infected grains is a major food safety issue especially in the export market. The use of
resistance cultivars offers the most effective approach to manage FHB in wheat. Therefore, several
studies have been conducted to identify FHB resistance QTL in wheat around the globe, however, most
of the identified QTL possess a small effect on resistance and a high-level of genotypic x environment
interactions. Conversely, several aboveground traits e.g. plant height, canopy and ear related traits have
been reported to be associated with low Fusarium infection. Thus, to identify the novel FHB resistance
QTL without a possible trade-off with agronomically important traits, a doubled haploid mapping
population derived from AAC Innova/AAC Tenacious was utilized. It was phenotyped for different
aboveground and FHB resistance related traits during 2015 to 2018 followed by SNP genotyping and
QTL analysis. QTL analysis resulted into a flowering pathway gene (Ppd-D1b) and two other major
QTL/genes (QFhb.lrdc-2D and Rht-B1a) which were associated with low FHB and derived from the wheat
cultivar (cv) AAC Tenacious. Among the three identified major QTL/genes, Ppd-D1b (photoperiod
sensitive allele) had largest effects on type-I and -II resistance. Haplotype and pedigree analysis showed
that Ppd-D1b was inherited along with tall allele of Rht8 through cv Neepawa and traces back to
Canadian heritage wheat variety Marquis.