Adaptability and yield stability of some maize cultivars in the Brazilian Northeast

Abstract

Twenty five cultivars of maize (Zea mays L.) were evaluated in 1994, in twelve different environments of the Northeast Region of Brazil. The trials were arranged in randomized block designs with three replications aiming to obtain knowledge concerning to the adaptability and yield stability of the cultivars in each environment. The significant effects related to environment, cultivars and cultivars x environments interaction gave the evidence of outstanding differences among that parameters. The hybrids showed better performance than the varieties, yielding in average 22.5% higher in relation to the environmental variations. Only the Cargill 505 and AG 510 hybrids showed poor adaptability in unfavorable environments. Taking in account the means presented by the varie-ties, CMS 39 was the most adjusted to the optimal genotype proposed in the model. None of the materials studied gave a determination coefficient (R²) lower than 80%, indicating a good production stability.