Padrão de emergência de plântulas de capim-capeta em função de diferentes densidades de sementes e profundidades no solo

Abstract

Wiregrass (Sporobolus indicus) is an invasive plant that has gained great relevance at pasture areas of Midwest and North of Brazil. The study on the behavior of seedling emergence is of fundamental importance for the adoption of management strategies for this weed. Because of this, the objective of this research was to evaluate the emergence pattern of Wiregrass seedlings as a function of seed density and sowing depth localization of seed on soil profile. The experiment was carried out in a in a completely randomized block design, with four replications, with treatments arranged at factorial scheme 3 x 8, being three seed densities (high, medium and low) associated with eight depths of seed localization at soil profile (0.0; 1.0; 2.0; 3.0; 4.0; 5.0; 6.0 and 7.0 cm). The effects of seed densities and sowing depth was evaluated by the number of emerged seedlings, the emergence speed index, relative emergence frequency, initial, mean and final emergence time and seedling emergence synchrony obtained over 27 days after sowing. The obtained results showed that the high density seed present higher emergence rate of wiregrass seedling when compared with two other densities. The increasing of seed depth on soil profile provides decreasing on seedling emergence of wiregrass. The relationship between seed density and soil depth has significative variation related to the seedling wiregrass emergence. The seed depth that promotes higher tax of seedling emergence of wiregrass is 2.0 cm for all seed densities. All seed densities have low or null seedling emergence at 6.0 cm and 7.0 cm of depth.