RESULTS

Phenotypic:

     Analysis of the phenotypic data revealed a significant negative relationship between years of registration for the 48 wheat cultivars and days to first heading (Figure 1), days to maturity (Figure 2), and head length (Figure 3).  Data analysis also revealed a significant positive relationship between year of cultivar registration and number of heads per plant (Figure 4), weight of kernels per head (Figure 5), weight of kernels per plant (Figure 6) and weight of 100 kernels per cultivar (Figure 7). No significant relationships were found between year of registration and plant height (Figure 8), number of kernels per head (Figure 9) or awns.  The proportion of cultivars with awns was 23%, and without was 77%.

Genotypic:

    Analysis of gel images (Figure 10) showed 43 polymorphic bands across the 12 primers. No significant relationships were found between the percent of polymorphic bands and year of cultivar registration (Figure 11) nor between the average number of polymorphic bands per cultivar and the decades of cultivar development (Figure 12).  More genetic variation was present in the cultivars registered pre-1920's followed by a reduction during the 1920 - 1960 period with an increase in genetic variation since then.  However, overall the trend is not significant.  An analysis of the genetic similarity (Figure 13) among the cultivars also revealed considerable genetic variability among them.  Pembina and Canthatch were the most similar genetically while Ladoga was the most dissimilar.  Three groups of cultivars were discerned from Figure 13.  The first group of cultivars (Red Fife to Canuck) tended to be the earlier developed cultivars, the second larger group of cultivars (Prelude to Lancer) tended to be mid to later developed cultivars, while the third group (Renown to Ladoga) tended to be developed in the mid years.  There appears to be no relationship between this genetic similarity analysis and the cultivar's pedigree nor ancestry as given by DePauw et al., (1995).