CULTIVAR BY ENVIRONMENT INTERACTIONS, YIELD STABILITY AND GROUPING OF TEST LOCATIONS FOR FIELD BEAN CULTIVAR TRIALS IN ONTARIO

Abstract

Yield data of six recommended cultivars grown at seven locations (L) over 6 yr (Y) in the Ontario field bean (Phaseolus vulgaris L.) cultivar trials were analyzed to examine cultivar by environment interaction components, to determine yield stability of cultivars, and to group test locations. Cultivar (C), C × L, and C × L × Y effects were highly significant with large variance components indicating the importance of cultivar and test locations. The C × Y interaction was not significant. When yield stability was evaluated using cultivar means, regression coefficients (b), and deviations from linear regression (S2d), Ex Rico 23 was identified as being stable and potentially high yielding. Test locations were grouped into four homogeneous subareas by a biological classification method. Since breeding or recommending cultivars for four small subareas is not practical, efforts should be devoted to improving average stability and yield potential by testing at locations representative of homogeneous subareas.Key words: Bean (field), Phaseolus vulgaris, yield testing, genotype × environment interactions