José Ricardo Mantovani

Produção de alface e acúmulo de nitrato em função da adubação nitrogenada

An experiment using pots under greenhouse conditions was carried out to evaluate the influence of nitrogen fertilization on the growth and nitrate accumulation of lettuce cultivars. The experimental design was of randomized blocks in a 5 x 5 factorial scheme, with four replicates. Treatments were five nitrogen rates: 0; 141,5; 283; 566 and 1132 mg/pot N as urea, and five lettuce cultivars: Lucy Brown, Taina, Vera, Veronica and Elisa. Maximum growth was observed in the treatment using 283 mg of N/pot. The use of higher rates did not increase plant growth but raised nitrate accumulation in shoot organs. Lucy Brown and Taina accumulated more nitrate than Vera, Veronica and Elisa cultivars.

Uso fertilizante de resíduo da indústria processadora de goiabas

The guava processing industry waste (GPIW) has been used in some areas, however is not known its effect on soil fertility. A greenhouse experiment was carried out to evaluate the effect of GPIW on soil fertility, using corn as testing plant. The experiment was in randomized blocks design combining five GPIW rates (0; 20; 40; 60 and 80 t ha-1) in the absence and the presence of mineral fertilization. The GPIW increased P and K concentration and behaved as a slow release source of N and P for corn.

Calagem e adubação com vermicomposto de lixo urbano na produção e nos teores de metais pesados em alface

The effect of urban waste vermicompost over dry matter and heavy metal concentration in lettuce tops, was evaluated in two greenhouse experiments, one with an Oxissol and another an Alfissol. The experiments followed a completely randomized design combining five liming levels, to elevate the degree of base saturation to 40; 50; 60; 70 and 80%, with five vermicompost rates of 0; 25; 50; 75 and 100 t ha-1, with four replicates. The use of urban waste vermicompost in higher rates than 50 t ha-1 limited the lettuce yield in both soils. Even at these rates, however, the lettuce did not become inappropriate as food from the point of view of heavy metal contamination.

Extratores para avaliação da disponibilidade de metais pesados em solos adubados com vermicomposto de lixo urbano

The objectives of this work were to select chemical extractants to evaluate the availability of heavy metals in soils treated with urban waste vermicompost and lime, and to verify the effects of these treatments in available contents of heavy metals in soils. Two experiments were carried out in greenhouse. An Oxissol was utilized in the first experiment and an Alfissol in the other. Lettuce was used as a testing plant in both experiments. The experiments followed a completely randomized design combining five liming levels, to elevate the base saturation to 40%, 50%, 60%, 70%, and 80%, with five vermicompost rates of 0, 25, 50, 75, and 100 tons ha -1 , with four replicates. The DTPA and the Mehlich 3 detected increase in Ni, Pb, Cu and Zn contents in clay and sandy soils fertilized with urban waste vermicompost. The DTPA is more efficient than Mehlich 1 and Mehlich 3 to evaluate the changes in available contents of heavy metals caused by increase of pH in clay soil. The Mn is the only element which availability is efficiently evaluated in both soils, and the recomended extractant is the DTPA.

Comparação de procedimentos de quantificação de nitrato em tecido vegetal

Nitrate content determination is important for food quality evaluation, but its determination is affected by interferences. The objective of this work was to compare nitrate determination procedures for vegetable tissues. In dry matter samples from three lettuce cultivars that received five levels of nitrogen in a greenhouse experiment, nitrate was extracted with deionized water and its determination was made by the cadmium column method, the distillation method, the salicylic acid method, and the method using the reductive mixture with zinc. The salicylic acid method and that of reductive mixture with zinc overestimated the nitrate content in lettuce dry matter, because they were influenced by the color of dry matter extracts and other interferences. The cadmium column and the distillation methods are the best for nitrate determination in vegetable tissues, but the simplicity and lower cost of distillation in relation to cadmium column method suggest that the first one must be recommended.

Nitrato em alface e mobilidade do íon em solo adubado com composto de lixo urbano

A contaminacao do meio ambiente por nitrato pelo uso agricola do composto de lixo urbano tem sido pouco estudada. O objetivo deste trabalho foi avaliar o efeito da adubacao com composto de lixo urbano no acumulo de nitrato em alface, na mobilidade no solo e nas perdas por lixiviacao de nitrato. Dois experimentos simultâneos foram realizados em casa de vegetacao, em colunas de PVC, em delineamento em blocos ao acaso, com cinco tratamentos e quatro repeticoes. Em um deles efetuou-se um cultivo de alface e, no outro, dois cultivos sucessivos. Os tratamentos constituiram-se de cinco doses de composto de lixo urbano, equivalentes a 0, 30, 60, 90 e 120 t ha -1 . As colunas receberam solo das profundidades de 0–20 (tratado com composto de lixo), 20–40 e 40–60 cm de um Argissolo, textura media, e uma muda de alface. O composto de lixo urbano nao torna a alface impropria para o consumo no que diz respeito a concentracao de nitrato, mas apresenta potencial de contaminacao de lencol freatico causado pelas perdas do ion por lixiviacao.

GROWTH AND PHYSIOLOGICAL RESPONSES OF TREE SPECIES (Hymenaea courbaril L., Peltophorum dubium (Spreng.) Taub. and Myroxylon peruiferum L. F.) EXPOSED TO DIFFERENT COPPER CONCENTRATIONS IN THE SOIL

1 Received on 13.06.2017 accepted for publication on 01.03.2018. 2 Universidade Federal de Lavras, Programa de Pós-Graduação em Botânica Aplicada, Lavras, MG-Brasil. E-mail: <danimarques.bio@gmail.com>. 3 Universidade José do Rosário Vellano, Instituto de Ciências Agrárias, Alfenas, MG-Brasil. E-mail: <adriano.silva@unifenas.br>, <jose.mantovani@unifenas.br> and <DalvanaSousa@hotmail.com>. 4 Universidade Federal de Alfenas, Instituto de Ciências da Natureza, Alfenas, MG-Brasil. E-mail: <thiagonepre@hotmail.com>. *Corresponding author.

EARLY GROWTH OF COFFEE PLANTS AND SOIL FERTILITY PROPERTIES IN RESPONSE TO COFFEE HUSK APPLICATION

Coffee processing generates large amounts of husk, which can be used as organic fertilizer if technical criteria are considered. This study investigated the effect of coffee husk, applied to or incorporated into the soil, on soil fertility properties, early crop growth and nutrient accumulation in coffee plants. The experiment analyzed coffee plants in a greenhouse in pots, in randomized blocks, in a 5x2 factorial arrangement plus a control treatment, with four replicates. The treatments consisted of the combination of five coffee husk rates (3.5; 7; 14; 28, and 56 t ha -1 ), applied in two forms: spread on the surface or incorporated into the soil, plus the control treatment, without husk application. Portions of 7 dm 3 soil were blended with lime, phosphate fertilizer, as well as coffee husk rates in the treatments with residue incorporation, and incubated for 30 days. Thereafter, one coffee seedling per plot was planted, the coffee husk rates were applied on the soil surface for the treatments without residue incorporation, and the plants were left to grow for 180 days. Coffee husk applied to or incorporated into the soil surface increases the K and organic matter contents of the soil, intensifies the early growth of coffee plants and accelerates N and K accumulation in the plant shoots. The application of coffee husk on the surface is more indicated than its incorporation into the soil, and the best rate at coffee planting is equivalent to 20 t ha -1 .

ATRIBUTOS DE FERTILIDADE E PRODUÇÃO DE HORTALIÇAS FOLHOSAS EM SOLOS ADUBADOS COM ESTERCO BOVINO

The effect of organic fertilization with cattle manure on fertility properties of soils with different clay contents was evaluated; as well as the influence of cattle manure fertilization on the production of lettuce, and on subsequent arugula and common chicory grown in these soils. The experiment with pot plants was arranged in randomized blocks and analyzed in a 3x6 factorial design with four replications. The treatments consisted of three soil types with different clay contents (166; 362; 565 g kg) and six cattle manure rates (0; 10; 20; 40; 80, and 160 t ha). Batches of each soil were manured, limed, filled in pots, moistened, and incubated for 30 days. Then, mineral base fertilization was applied and one lettuce seedling per each pot was grown. After lettuce harvest, the residual effect of organic fertilization was assessed in two subsequent crops, first arugula and then common chicory. The application of up to 160 t ha cattle manure reduces soil acidity and increases nutrient contents, particularly of P, K and Zn, in soils with 165 to 565 g kg clay content. Fertilization with cattle manure at rates of up to 160 t ha increases electrical conductivity of soils, without affecting growth and yield of the leafy vegetables. Cattle manuring increases the yield of lettuce, as well as of arugula and common chicory grown afterwards.