Semagn Kassa, Henriquez Maria Antonia, Iqbal Muhammad, Brûlé-Babel Anita L, Strenzke Klaus, Ciechanowska Izabela, Navabi Alireza, N'Diaye Amidou, Pozniak Curtis, Spaner Dean
Department of Agricultural, Food, and Nutritional Science, 4-10 Agriculture-Forestry Centre, University of Alberta, Edmonton, AB, Canada.
Morden Research and Development Centre, Agriculture and Agri-Food Canada, Morden, MB, Canada.
Front Plant Sci. 2023 Aug 23;14:1190358. doi: 10.3389/fpls.2023.1190358. eCollection 2023.
Fusarium head blight (FHB) is one the most globally destructive fungal diseases in wheat and other small grains, causing a reduction in grain yield by 10-70%. The present study was conducted in a panel of historical and modern Canadian spring wheat ( L.) varieties and lines to identify new sources of FHB resistance and map associated quantitative trait loci (QTLs). We evaluated 249 varieties and lines for reaction to disease incidence, severity, and visual rating index (VRI) in seven environments by artificially spraying a mixture of four isolates. A subset of 198 them were genotyped with the Wheat 90K iSelect single nucleotide polymorphisms (SNPs) array. Genome-wide association mapping performed on the overall best linear unbiased estimators (BLUE) computed from all seven environments and the International Wheat Genome Sequencing Consortium (IWGSC) RefSeq v2.0 physical map of 26,449 polymorphic SNPs out of the 90K identified sixteen FHB resistance QTLs that individually accounted for 5.7-10.2% of the phenotypic variance. The positions of two of the FHB resistance QTLs overlapped with plant height and flowering time QTLs. Four of the QTLs (, , , and ) were simultaneously associated with disease incidence, severity, and VRI, which accounted for 27.0-33.2% of the total phenotypic variance in the combined environments. Three of the QTLs (, , and ) were associated with both incidence and VRI and accounted for 20.5-22.1% of the total phenotypic variance. In comparison with the VRI of the checks, we identified four highly resistant and thirty-three moderately resistant lines and varieties. The new FHB sources of resistance and the physical map of the associated QTLs would provide wheat breeders valuable information towards their efforts in developing improved varieties in western Canada.
小麦赤霉病（FHB）是全球范围内对小麦和其他小粒谷物危害最大的真菌病害之一，可导致谷物产量降低10%-70%。本研究在一组加拿大历史和现代春小麦（L.）品种及品系中开展，以鉴定新的抗小麦赤霉病来源并定位相关的数量性状基因座（QTL）。我们通过人工喷洒四种菌株的混合物，在七个环境中评估了249个品种和品系对病害发病率、严重程度和视觉评级指数（VRI）的反应。其中198个的子集用小麦90K iSelect单核苷酸多态性（SNP）阵列进行了基因分型。基于从所有七个环境计算出的总体最佳线性无偏估计值（BLUE）以及国际小麦基因组测序联盟（IWGSC）RefSeq v2.0物理图谱，对90K中鉴定出的26,449个多态性SNP进行全基因组关联作图，确定了16个抗小麦赤霉病QTLs，每个QTLs分别解释了5.7%-10.2%的表型变异。其中两个抗小麦赤霉病QTLs的位置与株高和开花时间QTLs重叠。四个QTLs（、、和）同时与病害发病率、严重程度和VRI相关，在综合环境中占总表型变异的27.0%-33.2%。三个QTLs（、和）与发病率和VRI均相关，占总表型变异的20.5%-22.1%。与对照的VRI相比，我们鉴定出了四个高抗和三十三个中抗品系及品种。新的抗小麦赤霉病来源以及相关QTLs的物理图谱将为加拿大西部的小麦育种者在培育改良品种方面提供有价值的信息。
