Effect of soil moisture, organic matter and fertilizer application on brown eye spot disease in coffee plantations

Abstract

The aim of this study was to evaluate the effect of different soil coverings, fertilizers and soil conditioners on Brown eye spot (BES) management. The factors studied were arranged in a 3x2x5 factorial scheme, totaling 30 treatments, and allocated into a split-split plot arrangement. The experiment was arranged in a randomized block design with three replicates. The plots were composed of soil coverings, including polyethylene film, Urochloa decumbens, and an area with no cover. The subplots were treated with conventional and controlled-release fertilizers. The subdivided subplots were composed of soil conditioners, including organic compound, coffee husk, agricultural gypsum, hydroretentor polymer and check. The leaf and fruit BES incidence, foliage, soil moisture, plant growth, leaf area index, and productivity were evaluated. The data obtained were subjected to variance analysis and the Scott-Knott test (p < 0.05). U. decumbens and soil conditioners, including organic compound and coffee husk, promoted a higher soil moisture, therefore reducing the leaf and fruit BES and consequential defoliation. Despite the high soil moisture content present under the polyethylene film and subsequent promotion of vegetative growth, this soil covering provided a higher incidence and severity of BES in the fruits and leaves and defoliation. Controlled-release fertilizers, even though they did not promote a significant reduction in the incidence of BES, enabled improvements in the vegetative growth and foliage production. Agricultural gypsum, even though it promoted an improved productivity, caused nutritional imbalances and possible nutrient leaching, thus contributing to an increase in the occurrence BES, which caused a reduction of 72 to 81% in the leaf area index of coffee crop.