As a crop that is planted in all continents, except Antarctica, wheat (Triticum aestivum L.)owes its wide adaptability, at least in part, to the genes that control photoperiod sensitivity. Photoperiod sensitivity is an important physiological trait that influences the phenology of wheat, and the Ppd-1(Photoperiod-1) genes on group 2 chromosomes are significant regulators of this process. Photoperiod insensitivity is mainly controlled by the dominant Ppd-D1a allele, followed by the Ppd-B1a and Ppd-A1a alleles. However, Ppd-B1 has recently been shown to be present in different copy numbers, which alter the extent of photoperiod sensitivity, whereby genotypes with higher copy numbers are more photoperiod insensitive. The aim of this study is to further increase our knowledge of copy number variation of Ppd-B1 genes and their interaction with allelic variation to other Ppd-1 genes in Canadian winter wheats. Here, we employed a large panel of 450 Canadian winter wheat varieties to assess the frequency and the allelic variation at Ppd-D1, A1 and B1 and copy number variants at the Ppd-B1 as well as their effects on flowering time under field conditions. Results demonstrate that photoperiod sensitivity prevails in Canadian winter wheat: 68.75%, 81.5%, and 89.28 % genotyped carried sensitive alleles at the PPD-D1, PPD-A1, and PPDB1 loci, respectively. Most genotypes studied here carried one copy (78.57%), but the remainder carried two (9.37%) or more copies (12 %). In addition, we found that the frequency of the different copy number variants at PPD-B1 and allelic variation of PPD-1 genes have a substantial effect on the fine-tuning of flowering time. The panel was genotyped using Illumina iSelect wheat the 90K SNP chip, from which 20K polymorphic markers was used for various analyses. Using the phenotyping data from Elora, Ontario in 2017 and 2018 the association between these genotypic variations and different phenological and agronomic traits will be presented. The results are expected to relate to the geographical origin of the wheat accessions, which for the most part represents possible adaptation patterns.