GENOTYPE-ENVIRONMENT INTERACTION AND STABILITY OF GRAIN YIELD IN TRITICALES AND TRICEPIROS

Abstract

Triticales and tricepiros are good alternatives to fresh forage and grain in livestock meat and dairy systems in Argentina. The development of new cultivars requires good performance and stability in different environments, so it is necessary to know the genotype-environment interaction. In this paper, the genotype x environment interaction, stability and adaptability of experimental strains and cultivars for grain yield were analyzed by means of ecovalence, index Pi, regression, and AMMI and SREG methods. During 2009-2012, thirty-two strains of triticale and eleven of tricepiro were evaluated in Río Cuarto, Cordoba Province, and Santa Rosa, La Pampa Province, Argentina. A randomized complete block design, and a sample of 1 m2 per plot to analyze grain yield (kg ha-1) was used. The average yield of the trials was 2,628 ± 357 kg ha-1. Highly significant (p < 0.01) differences were found for the main effects: genotype (F = 5.64), environments (F = 401.5) and the genotype-environment interaction (F = 1.66). None of the methods to estimate the genotype-environment interaction, stability and adaptability of the tested genotypes was entirely satisfactory by itself. The ecovalence method presented poor resolution, while the remaining methods showed some coincidences. The combination of the regression with the site regression GGE biplot was the best method to study the genotype x environment interaction and identify stable genotype and high grain yield. The results allowed identifying experimental strains to release as cultivars.