Genotype/genotype × environment biplot analysis for cultivar evaluation and mega-environment investigation in primocane-fruiting red raspberry

Abstract

Primocane-fruiting (PF) red raspberry (Rubus idaeus L.) cultivars are being grown in many regions as their popularity increases. However, testing of this perennial fruit crop is expensive and requires many years. Large genotype (G) × environment (E) interactions can make identification of superior genotypes difficult. The G/G × E (GGE) biplot can be used to measure cultivar performance and group locations into mega-environments. The GGE biplot was applied to yield trial data of three PF red raspberry cultivars Autumn Bliss, Heritage, and Redwing grown in 17 environments (year-location combinations). The 17 environments encompassed six locations in Ontario and Quebec, Canada between 1989 and 1996. 'Autumn Bliss' produced the highest yields in 11 of 17 environments. 'Heritage' was usually the lowest yielding cultivar. Two mega-environments were identified based on the performance of 'Autumn Bliss' and 'Redwing'. Some environmental variables were likely to be responsible for the discriminating ability of the test environments as they were correlated with the primary effects. The GGE biplot was an effective analysis to determine mega-environments and the cultivars best adapted to each.