Análise de adaptabilidade e estabilidade e correlação entre variáveis morfológicas e produtivas em cultivares crioulas de milho

Abstract

Maize landraces have great genetic variability and are considered important sources of alleles for use in Genetic Improvement Programs and also in family farming systems. The objectives of this thesis were to evaluate and compare the parameters of adaptability and stability for the morphological and productive variables in maize landraces and to estimate the correlation between morphological and productive characters. The experiments were conducted in the municipality of Ibarama, RS, in three sowing seasons in the 2015/2016 and 2016/2017 harvests, and morphological and productive characters of 11 cultivars and improved maize were evaluated. For plant height and spike insertion height, the 'Amarelão' cultivar, in addition to the lower averages, presents broad adaptability and stability, and 'Brancão' presents specific adaptability to favorable environments and, 'Cunha', low stability for both characters . Among the productive characteristics, the productivity and the weight of a thousand grains are those that determine the greater specificities of the genotypes in favorable and unfavorable environments, as well as the lower stabilities. Morphological and productive characters do not correlate with each other. Maize plants of higher stature are associated with those that produce spikes with higher number of rows, number of grains per row and weight of a thousand grains, but with lower productivity,