Abstract

MEDINA, Sol et al. Evaluación de la estabilidad del rendimiento de variedades de maíz en siete localidades de venezuela. Agronomía Trop. [online]. 2002, vol.52, n.3, pp.255-276. ISSN 0002-192X.

Summary In order to evaluate yield stability of seven varieties of maize, obtained from a recurrent selection of a sib program, a test was designed which included seven experimental varieties, as well as two hybrids and three commercial varieties used as control. Seven tests were made in the same number of locations found in Venezuela maize areas, during the rainy period of 1993. A randomized complete block design was used with four replications. Grain yield (kg plot-1) adjusted to 12% humidity was evaluated and transformed to t ha-1. For the evaluation of yield, an analysis of combined variance through the localities and an analysis of stability was performed according to the AMMI (additive main effects and multiplicative interactions) model. Through the analysis of the combined variance it was possible to detect high significant differences for the effects: locations, genotypes and interactions genotype by location. The study of the interaction genotype by location provided different patterns of responses between varieties and hybrids. Tuxpeño 1RC, Mercedes 90, Máquina C3 Apure 1990, Máquina C1 Apure 1988 and Compound CENIAP 90, conformed the group of varieties with higher profits and stability (Principal component 1, PC1 value close to 0). Hybrids, on the other hand showed a lower stability in the environmental conditions selected during the evaluation year. Hybrid CENIAP PB-8 reached a high yield (5, 02 t ha-1) and PC1 close to 1, where as hybrid CENIAP-81 presented low yields (4, 33 t ha-1) and a negative PC1

Keywords : Principal components; genotype by locality interaction;; multiplicative interaction; AMMI model; additive effect.