Yield and conservation of onion bulbs are influenced by nitrogen (N) availability in the soil, which is required in large amounts. This study aimed to evaluate the effect of N application rates and splitting on the plant nutritional status, yield and conservation of onion bulbs after harvest. Three field experiments were carried out in Southern Brazilian Haplumbrepts. Treatments consisted of a factorial combination (4 x 3) involving four N rates (0, 50, 100, and 200 kg ha-1) and three times of sidedressing (only 45, […]

Nitrogen is the most important nutrient for rice (Oryza sativa L) yields. This study aimed to evaluate the response of upland rice cultivars to N rate and application times in a randomized block design, in subdivided plots with four replications. The studied factors were five rice cultivars (BRS MG Curinga, BRS Monarca, BRS Pepita, BRS Primavera, and BRS Sertaneja), three application times (100 % at planting, 50 % at planting – 50 % at tillering and 100 % at tillering) […]

Especially under no-tillage, subsuface soil acidity has been a problem, because it depends on base leaching, which has been associated with the presence of low molecular weigth organic acids and companion anions. The objective of this study was to evaluate exchangeable base cation leaching as affected by surface liming along with annual urea side-dressing of maize and upland rice. Treatments consisted of four lime rates (0, 1500, 3000, and 6000 kg ha-1) combined with four nitrogen rates (0, 50, 100, […]

Appropriate nitrogen availability during the common bean cycle is essential to ensure high grain yield and quality. This nutrient can be absorbed by the roots and leaves. However, there are still doubts about the efficiency of N leaf application and the influence on common bean grain quality. Therefore, the purpose of this study was to evaluate the effect of N sidedressing and leaf application on common bean grain yield and quality. The experiment was carried out in the dry growing […]

Crop species with the C4 photosynthetic pathway are more efficient in assimilating N than C3 plants, which results in different N amounts prone to be washed from its straw by rain water. Such differences may affect N recycling in agricultural systems where these species are grown as cover crops. In this experiment, phytomass production and N leaching from the straw of grasses with different photosynthetic pathways were studied in response to N application. Pearl millet (Pennisetum glaucum) and congo grass […]

Nitrogen fertilizers increase the nitrous oxide (N2O) emission and can reduce the methane (CH4) oxidation from agricultural soils. However, the magnitude of this effect is unknown in Southern Brazilian edaphoclimatic conditions, as well as the potential of different sources of mineral N fertilizers in such an effect. The aim of this study was to investigate the effects of different mineral N sources (urea, ammonium sulphate, calcium nitrate, ammonium nitrate, Uran, controlled- release N fertilizer, and urea with urease inhibitor) on […]

The great difficulty of incorporation of N fertilizers into the “green sugarcane” system causes concern and since urea is the most commonly used source, there is the risk of loosing NH3 through volatilization. For this reason, a field experiment was undertaken (in a Hapludox Typic) with the objective of evaluating the agronomic efficiency of ammonium chloride on stubble of the second ratoon (SP89 1115), as well as its residual effect on the subsequent cycle (third ratoon). The experimental design was randomized […]

Nitrogen has strong impact on potato yield and its effects on plants can be evaluated by specific nutritional diagnostic techniques. The objective of this work was to determine the optimum economical N rate for tuber yield and to estimate the critical value of plant N indices in leaf of two potatoes cultivars. The experiment had a 4×2 factorial in a completely randomized block design with four replications, with four N levels (0, 100, 200 e 400 kg ha-1 of N, pre-planting applied […]

Maize yield has increased with the development of modern cultivars and the demand for N has followed the same trend. The objective of this study was to evaluate the effect the timing of N application on grain yield and distribution in maize plant components in the presence and absence of Mo fertilizer under no-tillage. The experiment was conducted in the 2006/07 growing season, at the Experimental Station of Coimbra-MG. The experiment was arranged in a randomized block with three replications […]

The aim of this study was to evaluate the N losses due to volatilization at different rates of common urea, polymer coated urea and urease inhibitor-treated urea in the out-of-season corn, using semi-open static collectors. The treatments consisted of N levels on side-dressing fertilization with urea in different treatments: (a) control (without N), (b) urea 40 kg ha-1 N, (c) urea 80 kg ha-1 N, (d) polymer coated urea 40 kg ha-1 N, (e) polymer coated urea 80 kg ha-1 […]