Modelo logístico de crescimento de cultivares crioulas de milho e de progênies de meios-irmãos maternos em função da soma térmica

Abstract

Corn is one of the crops that produce more in the world, it has a wise geographic distribution, because of the big genetic variability present including creole cultivates. The objective of this study was to evaluate the growing ‘Amarelão’ creole cultivate, ‘Lombo baio’ and ‘Oito carreiras’ and also maternal progenies of half-brothers of this cultivate. This experiment was done in the agricultural year 2012/2013 in Santa Maria, RS. It was used the block delineation aimlessly with four repetitions and constituted portions by two lines of five meters to the creole cultivates and lattice delineation with three repetitions and portions constituted by a five line meters to the progenies with a spacing of 0.2m between each plant and between lines of 0.9m. It was done five evaluations of the plant height and leaves numbers by plant and the growing curves were adjusted by logistic model because of the thermal sum accumulated. The logistic model was adequate for the adjustment of the growing curves. The ‘Amarelão’ creole cultivate, ‘Lombo baio’ and ‘Oito carreiras’ presented the higher plant hight and the biggest number of leaves by plant in comparison to progenies of maternal half-brothers.