Is it possible to minimize the interference of the weed Urochloa decumbens under the initial growth of the coffee tree at different phosphorus fertilizations?

Abstract

The coffee tree presents slow initial growth, and crops in form leave part of the soil exposed, favoring the development of weeds. In this way, there is competition for space, light, and nutrients, such as the phosphorus applied when planting seedlings. Alternatives that minimize stresses related to nutrition and competition with weeds are needed. Thus, the objective was to evaluate the different effects of sources of phosphorus fertilization on the initial growth of coffee plants in competition with the weed Urochloa decumbens. The experiment was carried out in a greenhouse, in DBC with a 4 x 5 factorial scheme, referring to four levels of U. decumbens infestation (null - coffee tree free of competition, low - one plant/pot, medium - two plants/pot and high – four plants/pot) and five sources of phosphorus (conventional MAP, polymer-coated MAP, bran organomineral, pelleted organomineral, and control treatment - without fertilization). Coffee plants and U. decumbens lived together for 120 days in the same pot. Coffee plant growth was evaluated in terms of height, shoot and root system dry matter, and leaf phosphorus content for coffee and U. decumbens plants. The weed proved to be a strong competitor, as the highest levels of infestation caused serious damage to the initial growth of the coffee tree. However, phosphate fertilization with the use of pelleted and bran organomieral provided a lower level of interference to coffee plant growth, minimizing the competitive advantage of the weed, and providing better results for the variables of growth and phosphorus absorption.