Desempenho produtivo de híbridos de milho safrinha sob diferentes densidades populacionais

Abstract

Corn (Zea mays L.) is one of the main global agricultural crops, with growing economic and social importance in Brazil, with Piauí being a prominent production center. The success of the crop depends on the adoption of adjusted management practices, with population density being a determining factor that regulates intraspecific competition for light, water, and nutrients. Therefore, this study aimed to evaluate the productive potential of second-crop corn hybrids subjected to different plant densities, seeking to identify the ideal configuration for maximum agronomic performance. The experiment was conducted in Baixa Grande do Ribeiro, Piauí, in a second-crop system, using a completely randomized factorial design with three populations (fifty thousand, fifty-five thousand, and sixty thousand plants per hectare) and two commercial hybrids. Yield components such as ear weight, number of grains per ear, and thousand-grain weight, as well as grain yield, were evaluated. The results indicated a significant interaction between the genetic material and the tested population. Hybrid 1 achieved its highest productivity at the lowest density (one hundred and sixty-five sacks/ha), while Hybrid 2 showed better results at the intermediate density (one hundred and sixty-three sacks/ha). Furthermore, there was a progressive reduction in the number of grains per ear with increasing density for both materials, and the Thousand Grain Weight of Hybrid 1 was more sensitive to population variation than Hybrid 2. It is concluded that the plant population that maximizes productivity is not universal, making it crucial to determine the ideal density for each genotype in the second-crop cultivation system, optimizing productive potential and tolerance to environmental stresses