The relation between GxE interaction and the number of locations in series of oilseed rape trials

The problem of the selection of locations (experimental stations) for experiments on oilseed rape is considered. The results of 138 experiments conducted by the Research Centre for Cultivar Testing (COBORU) in the period 2006-2010 at 41 experimental stations form the basis for all considerations. The method applied earlier by Pilarczyk and Fraś (2007, 2010) for analysis of similar results concerning winter wheat was utilized here. However, because of the high degree of non-orthogonality of the data (slightly overlapping sets of varieties among years) only analyses of single-year series were possible. The locations with a high contribution to the genotype-environment interaction were identified.