Multidimensional Analysis of Diversity in Genotypes of Winter Oilseed Rape (Brassica napus L.)

The effect of genotype, environment (year, location) and their interaction on seed yield and important breeding traits of 25 genotypes of winter oilseed rape were investigated under field conditions in Greater Poland. Multi-environmental field experiments were conducted in a randomized block design with four replications during three growing seasons in two locations. Five traits, such as the beginning of flowering, seed yield and its structure, the length of siliques, the number of seeds per silique and the weight of 1000 seeds were recorded. The tested Brassica genotypes showed significant differences in terms of yield and other investigated traits across harvesting years and growing locations. Analysis of variance indicated that the main effects of genotypes, locations and years as well as all interactions were significant for all traits of study. The correlation coefficient between the investigated traits displayed strong negative relationships between seed yield and the beginning of flowering (except E2). The use of multivariate statistical methods in this study allowed for the simultaneous characterization of 25 tested genotypes in terms of several traits. Visualization of the experimental results and finally the distribution of Brassica genotypes in space of two first canonical variates showed a variation between the cultivars, double low, resynthesized and lines with changed fatty acid content in terms of yield and its components, as well as the beginning of flowering.