Procedural Approach for Assessing Cultivar-Location Data: Pairwise Genotype-Environment Interactions of Test Cultivars With Checks

A simple procedure for assessing cultivar-location data is proposed. The procedure consists of comparisons between checks and each of the test cultivars to find those test cultivars for which comparison with the checks can be done ignoring variability among locations, and to isolate those for which a location-by-location comparison is advisable. Since the level at which a comparison-wise genotype-environment interaction is deemed to be important can be set by the user, this represents a great simplification of the assessment process. A set of regional trial data was used as an example to demonstrate the approach. The complementary nature of this method with cluster analyses which group cultivars or locations is discussed.