Falhas na semeadura : efeitos no desenvolvimento e produção da soja

Abstract

When the plants are not adequately distributed in the area, due to problems in seed distribution or difficulty in seedling emergence, faults appear in the planting line, which cause the nutrients to be absorbed with less efficiency by the plants, and may result in losses in the yield of the cultivar. Given this scenario, the present study was designed to evaluate whether the development and productivity of soybeans is influenced by faults in the planting row. A randomized block design (BCT) with six treatments and five repetitions was used, totaling 30 plots. The treatments consisted of gaps in the number of plants, being evaluated plots with no gaps (control), one, two, three, four and five gaps every 2 m of seeding furrow. Each plot consisted of four planting rows spaced 0.45 meters apart and four meters long, with the useful area of the plot equal to 3.6 m². The following were evaluated: plant height (PA), diameter of the main stem (DHP) at five centimeters from the ground, number of branches (NR), number of pods per plant (NVP), number of grains per pod (NGV), pods with three grains (VT), pods with two grains (VD), single pods with one grain (VS), number of grains per pod (NGV), thousand seeds mass (MMS) and grain yield (PG), the last two had their humidity corrected to 14% (commercial standard). The plant failures did not interfere in the characteristics plant height, stem diameter and number of branches, vegetative growth of soybeans. The presence of plant failures resulted in differences in the number of pods, pods with three grains and the number of grains per plant. From the results it can be concluded: a) The occurrence of faults in the soybean crop rows does not interfere in the morphology of the plant. b) The faults in the sowing row result in a greater number of pods per plant and in pods with three grains or more. c) The presence of faults in the sowing row does not interfere in the production and productivity of soybean. d) The plasticity of soybean can be explained by the increases in the number of pods, pods with three grains or more and in the increases in the mass of grains per plant.