Volume 29, Number 1, 2005

Chemical control of green cover crops is common in no-till systems and nutrient mineralization of the residues left on the soil surface can be intensified by rainfall over time after the plant desiccation. Potassium leaching from six green cover crops was evaluated as affected by rainfall simulated at different stages after the herbicide application. Pearl millet (Pennisetum glaucum), guinea sorghum (Sorghum vulgare), black oat (Avena strigosa), triticale (Triticum secale), Indian hemp (Crotalaria juncea), and brachiaria (Brachiaria decumbens) were grown under […]

The presence of heavy metals can restrict the use of sewage sludge as a source for plant nutrients since they may contaminate soil, aquifers and plants. Urban sewage sludge from the Treatment Station of Ilha do Governador (ETIG), Rio de Janeiro, Brazil, was enriched with 1.667 mg kg-1 Cd and 8.000 mg kg-1 Zn. After 20 days of incubation under a constant humidity of 50% (g g-1), doses of 0, 20, 40 and 80 t ha-1 were applied to two soil samples (red-yellow Latosol (LV) and red-yellow Argisol […]

Biossolid has been used in agriculture as nutrient source and to improve soil physical attributes. The effect of biossolid on the aggregate stability and soil penetration resistance of a medium texture Oxisol (LVd) and clayey Oxisol (LVef) in Jaboticabal (SP) were evaluated. Dry biosolid mass was applied with a harrow at rates of 0.0, 25.0, 47.5, 50.0 Mg ha-1, incorporated at 0.1 m depth before sowing the maize. Samples were collected in the fifth year after the maize harvest from the 0.0-0.1, 0.1-0.2, […]

This study aimed to evaluate the speed of manure decomposition at different depths. Donkey, cow, goat, and sheep manure was used after stove drying at ± 65 °C. 20 g of each manure was wrapped in nylon bags and applied superficially or buried at 10.0 cm depth. Monthly, a nylon bag/plot was collected. The material was cleaned to evaluate decomposition, oven-dried and weighed to determine the loss percentage in relation to the initial weight. Decomposition was slow in the first thirty days when ± 95 % […]

Fertilizer recommendations for banana plantations should be technically sound and, mainly, more adjustable on a scientific base than the usual recommendation tables. A system was developed to estimate recommendable nutrient doses for banana (FERTICALC®-Bananeira), by means of modeling nutrient balance. This nutrient balance is obtained by the difference between the crop nutrient demand and supply through soil and plant residues. When the demand is higher than the supply, fertilizer application is recommended; when it is lower or equal to the […]

The effects of urban waste compost (UWC) on the chemical properties of a Rhodic Eutrustox and on the nutrition of gladiolus (Gladiolus grandiflorus) were studied. The gladiolus plants variety Red Beauty were field cultivated from August 1999 to January 2000. The experiment was set up in a randomized complete block design with six treatments and four replications. The treatments were: T1 – mineral fertilizer (MF); T2 – 10.0 t ha-1 of UWC; T3 – 20.0 t ha-1 of UWC; T4 – MF + 15.0 t ha-1 of UWC; […]

Soybean in symbiosis with Bradyrhizobium japonicum is able to satisfy its nitrogen (N2) demand with biological nitrogen fixation (BNF). However, BNF can be affected by molybdenium deficiency because this micronutrient is part of the nitrogenase enzyme responsible for the process. An experiment was conducted under field conditions on a Red Latosol (Oxisol) in Palotina, state of Paraná, Brazil. The effects of seed treatments with Mo, B. japonicum inoculation as well as foliar Mo fertilization on soybean yield were evaluated. Four […]