Implications of predictable and unpredictable environmental factors in common bean VCU trials in Minas Gerais

Abstract

The aim of this study was to estimate the relative contribution of predictable and unpredictable environmental variations to the lines x environments interaction and verify if it is possible to reduce the number of evaluation environments of the Value for Cultivation and Use Trials (VCU) conducted in Minas Gerais, Brazil. We used grain yield data from 166 VCU trials of common bean conducted in the state from 2002 to 2012. Individual and joint analyses of variance of the environments were carried out for each two-year period and the contribution of each source of variation to total variation was estimated. Subsequently, ecovalence was used, and joint analyses of variance were made considering different numbers of environments by means of resampling. The source of variation that most contributes to the interaction is location. Reduction in the number of environments in the VCU trials is not a good strategy for recommendation of cultivars in Minas Gerais.