População de plantas e componentes de produção de milho doce

Abstract

The objective of this work was to evaluate the population density effect of plants upon yield components of two sweet corn hybrids during two agricultural years. The experiments were placed in an area of eutrophic Red Nitosol, argyle texture, in Maringá County, PR, during summer period of 2009 and 2010. The experimental design was randomized blocks with four replications. The treatments based on combination among hybrids (Tropical Plus e RB - 6324) and plant population density (40.000, 55.000, 70.000, 85.000 and 100.000 plants per hectare), in two growing seasons (2009 and 2010), using, in this way, the factorial scheme 2 x 5, since it was possible to perform the joint analysis of experiments, for all characteristics evaluated. It was observed an effect of plant population upon all response variables evaluated. The population increment provided, in general, increase in plant height and height of ear insertion, and reduction in culm diameter. The linear increase in leaf area index, associated with good weather conditions, besides an appropriate irrigation and fertilization, made withal, in 2009 and 2010, the total productivity of husked ears, like the yield of commercial ears without straw, presented growth trend, with increasing plant population. In higher plant densities, it was noted reduction in the length and diameter of the ear, throughout, during all interval population densities used, the values of these characteristics were within the standard for marketing and industrial use. In 2010, for Tropical Plus, the increase in plant population had a positive effect on the number of kernels per ear row. It also found that are produced lighter ears, even as ears of sweeter grains and with lower concentration of starch, when the population density is increased.