Abstract

The present study aimed to evaluate the grain yield adaptability and stability of 20 blackeyed cowpea genotypes under rainfed agriculture in North, Northeastern and Central/Western Brazil. Three parametric methodologies and one non-parametric methodology were used. We found significant differences among genotypes, environments, and interaction between genotypes and environments. The traditional method indicated that the MNC05-832B-230-2-3 line was the most stable but had low grain yield. The linear regression indicated that the California Blackeye-3 and California Blackeye-5 cultivars had wide adaptability and stability. The bi-segmented regression model indicated that the MNC04-783B-7-3 and California Blackeye-3 genotypes exhibited adaptation to favorable and unfavorable environmental conditions, respectively. The non-parametric method characterized the MNC04-783B-7-3 line as the most suitable and stable genotype. Spearman´s rank correlation showed that some methodologies should not be used simultaneously and that others should be used complementary to each other.

Key words: Vigna unguiculata, genotype × environment interaction, non-parametric method, parametric method, seed yield.