Plantas de cobertura na lavoura cafeeira em formação

Abstract

This study aimed to evaluate the effects of cover crops in coffee plantation in the formation phase. The experiment was conducted at the Federal University of Lavras - UFLA, in Lavras, state of Minas Gerais, from December 2016 to December 2018. The experiment was conducted using a randomized compleste block design arranged in a 4x5 factorial scheme, totaling 20 treatments using subdivided plots with three replicates. Four soil cover plants were studied (jack beans, velvet beans, forage peanut and brachiaria) plus a control treatment with only spontaneous vegetation. Four planting distances (or spontaneous vegetation) were maintained in relation to the coffee plantation (25, 50, 75 and 100 cm). The growth of coffee trees, soil moisture, soil penetration resistance, physiological characteristics, soil chemical attributes, nutrient leaf contents, and weed phytosociology were evaluated. Furthermore, the allelopathic potential of some of these cover plants was analyzed in seeds of lettuce and Euphorbia heterophylla. A randomized complete design was used in a 3x4 factorial scheme (totaling 12 treatments), in which each Petri dish represented an experimental unit. The first factor was represented by the cover plants (jack beans, velvet beans and brachiaria) and the second factor was represented by the concentration of extracts of these plants (0, 2.5, 5 and 10 w/v). The germination, radicle length and germination speed index of the test plants were evaluated. For analysis of variance, the Scott-knott test was used for the qualitative variables and regression was used for the quantitative variables. Multivariate analysis of the data was further used. Therefore, it is recommended the intercropping of either jack beans or velvet beans cultivated with a distance of 1 meter from the planting line of coffee trees.