Avaliação de híbridos de milho sob três densidades populacionais em fronteira agrícola no Maranhão

The aim of this study was to evaluate the agronomic performance of corn hybrids in three densities. The experimental design was randomized block in factorial 2x3 with four replications. No interaction between cultivars and density for any of the characters. Significant differences among hybrids, except for the number of rows of grain. The hybrid 2B707 showed greater height, ear length, number of kernels per row, ear weight and grain yield. The 2B710 hybrid overcomes 2B707 in ear diameter and grain weight. It was found that increasing the density a significant decrease in spike length, number of kernels per row and average ear weight. Also there was a decrease, but not significantly, with increasing density, the number of rows and weight of 100 grains. The ideal population was 55,000 plants where the yield was higher.O objetivo deste trabalho foi avaliar o comportamento agronômico de híbridos modernos de milho em três densidades populacionais. O delineamento experimental foi o de bloco casualizados em esquema fatorial 2x3 com quatro repetições. Não ocorreu interação significativa entre híbridos e densidades para nenhum dos caracteres avaliados. Ocorreram diferenças significativas entre híbridos, exceto para o número de fileiras de grãos. O híbrido 2B707 apresentou maior altura, comprimento de espiga, número de grãos por fileira, peso médio de espiga e rendimento de grãos. O híbrido 2B710 supera o híbrido 2B707 no diâmetro da espiga e no peso de grão. Verificou-se que com aumento da densidade ocorreu diminuição significativa do comprimento da espiga, número de grãos por fileira e peso médio de espiga. Também ocorreu diminuição, porém não significativa, com o aumento da densidade, do número de fileiras e do peso de 100 grãos. A população ideal foi a de 55.000 plantas, onde o rendimento de grãos foi mais elevado. Evaluation of maize hybrids under three densities in the agriculturalfrontier in Maranhão State, BrazilThe aim of this study was to evaluate the agronomic performance of corn hybrids in three densities.The experimental design was randomized block in factorial 2x3 with four replications. No interactionbetween cultivars and density for any of the characters. Significant differences among hybrids,except for the number of rows of grain. The hybrid 2B707 showed greater height, ear length, numberof kernels per row, ear weight and grain yield. The 2B710 hybrid overcomes 2B707 in ear diameterand grain weight. It was found that increasing the density a significant decrease in spike length,number of kernels per row and average ear weight. Also there was a decrease, but not significantly,with increasing density, the number of rows and weight of 100 grains. The ideal population was55,000 plants where the yield was higher