Produtividade e qualidade de sementes de soja em função da densidade e localização na planta

Abstract

To maintain the growth of the culture in the country, several technological advances have occurred, among them are the quality of the seeds used in the soybean crops. The quality of seeds is a very important factor, as it ensures a fast and uniform plant stand in the crop. The production of high quality seeds will depend on the sum of all genetic attributes. In order to increase productivity per cultivated area, and high yields are only obtained if conditions are favorable at all stages of the crop, a number of factors must be considered, the maximum yield to be reached by soybean is determined by the optimization of the plant's ability to maximize the interception of solar radiation during the early vegetative and reproductive stages. The objective of this work is to evaluate the yield and the physiological quality of seeds produced in the different thirds of the plant (main and secondary branches) in the different populations. The experiment was conducted in the State of Rio Grande do Sul, in the city of Pelotas, at the Visconde da Graça Agrotécnico College (CAVG), a campus linked to the Federal Institute of Education, Science and Technology of the South of Rio Grande do Sul (IFSul). The experiment was conducted in the 2017/2018 harvest. The second stage of the work was conducted at the LDAS Seed Analysis Laboratory, at the "Eliseu Maciel" School of Agronomy (FAEM), Federal University of Pelotas. A 3x3x2 triffatorial experiment (population density x thirds x branches) was installed, arranged in randomized blocks, with 4 replicates. The data were submitted to analysis of variance using the statistical software Rstudio, and there was a significant correlation between the factors. Secondary branches contribute to a greater proportion of seed yield in smaller populations. In a soybean plant the largest number of seeds is found in the middle third. The highest percentages of germination are in secondary branches, except in the middle third where there is no difference between thirds. Seeds produced in the lower third of the plant have vigor inferior to the other thirds.