Yield adaptability and stability of semi-prostrate cowpea genotypes

The objective of this work was to evaluate the yield adaptability and stability of semi-prostrate cowpea (Vigna unguiculata) genotypes. Twenty cowpea genotypes were evaluated using the additive main effects and multiplicative interaction (AMMI) model with supplementary genotype and environment. The trials were carried out in nine environments (Balsas, MA, 2010; Balsas, MA, 2011; Bom Jesus, PI, 2010; Bom Jesus, PI, 2011; Sao Raimundo das Mangabeiras, MA, 2010; Sao Raimundo das Mangabeiras, MA, 2011; Sao Joao do Piaui, PI, 2011; Campo Grande do Piaui, PI, 2011; Buriti, MA, 2011) of the Mid-North region of Brazil in a randomized complete block design with 20 treatments and four replicates. The effects of genotypes, environments, and genotype x environment interaction were significant. Genotypes differed as to yield adaptability and stability. The line MNC03-736F-2 presented genes for yield adaptability and stability. Among the evaluated genotypes, BR 17-Gurgueia and Pingo-de-Ouro-1-2 are the most predictable, and BRS Xiquexique is the most adapted. Among the test sites, Balsas, MA is the most appropriate for selection of genotypes superior for yield adaptability and stability.