Nitrogen sidedressing and molybdenum application to untilled corn and nitrogen (15n) allocation in the plant
01/Aug/2010
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 […]
Soil aggregation in a crop-livestock integration system under no-tillage
01/Aug/2010
Grazing intensities can influence soil aggregation, which can be temporarily and permanently affected. The objective of this study was to evaluate the aggregate stability in water at the end of a soybean cycle and during pasture development in a crop-livestock integration system under no-tillage and grazing intensities. The experiment was initiated in 2001, in a dystrophic Red Latosol, after soybean harvest. Treatments consisted of pasture (black oat + Italian ryegrass) at heights of 10, 20 and 40 cm, grazed by young […]
Chemical phophorus extractors used as environmental indicators in sewage-sludge treated soil
01/Aug/2010
Sewage sludge (SS) application to agricultural soils can raise the levels of some nutrients inadequately, for example P. In practice, the applied SS doses are based on the N requirement of crops, in which the P requirement or final destination of the applied P in the residue is not taken into account. Phosphorus is often associated with the eutrophication of water bodies, for being transported by runoff. The objective of this study was to evaluate if three chemical extractors used […]
Nutrient extraction and export by fully irrigated sugarcane varieties
01/Aug/2010
A review of technology research supporting the Brazilian sugaralcohol sector shows that only sporadic studies with irrigated sugarcane have been developed to investigate nutritional requirements. In this context, the objective of this study was to quantify the capacity of extraction and export of N, P, K, Ca, and Mg as well as the nutritional requirement for the production of one ton of stalk per hectare (TCH) in the plant cane cycle of 11 sugarcane varieties (SP79-1011, RB813804, RB863129, RB872552, RB943365, […]
Soil quality indicators in lead mining and metalurgy area. II – Mesofauna and plants
01/Aug/2010
The influence of soil management or the contaminant application to the soil, usually induce to a quicker response in the soil mesofauna than in other pedogenic properties; these organisms are therefore good environmental quality indicators. The aim of this study was to identify and quantify the organisms groups of the soil mesofauna and determine Pb and Zn contents in plants in the mining and metallurgy plant in Adrianópolis (PR),to originate biological indicators of the quality of these solis. At the […]
Potassium fertilizer management for sugar cane
01/Aug/2010
Brazil is the largest sugar cane producer in the world and, due to the increasing interest in renewable energy sources, the cultivated area is expanding. Sugar cane is usually planted in soil with low nutrient levels, which can limit the yield. In sugar cane, potassium is basically applied in the furrow, which can decrease the K use efficiency due to leaching or salinizaton to plant roots. The goal of this study was to evaluate stalk yield and technological properties of […]
Liming influence on soil chemical properties, nutritional status and yield of alfalfa grown in acid soil
01/Aug/2010
Alfalfa is an important forage crop with high nutritive value, although highly susceptible to soil acidity. Liming is one of the most efficient and prevailing practices to correct soil acidity and improve alfalfa yield. The objective of this study was to evaluate response to liming of alfalfa grown in a greenhouse on a Typic Quartzipsamment soil. The treatments consisted of four lime rates (0, 3.8, 6.6 and 10.3 Mg ha-1) and two cuts. Alfalfa dry matter increased quadratically with increasing lime rates. […]
Coffea arabica L. nutritional status survey based on dris, in the Upper Paranaíba region – Minas Gerais
01/Aug/2010
A striking characteristic of soils under savanna vegetation is the low natural fertility, as in soils in the Upper Paranaíba region – MG. This characteristic is aggravated by the use of low fertilizer quantities, which may cause nutritional imbalance in plants. The objective of this study was to evaluate the nutritional status of coffee plants in the Upper Paranaíba region – MG, using the integrated system for diagnose and recommendation (DRIS) to interpret leaf analyses and apply the fertilization response […]
Attributes of irrigated rice and soil solution as affected by salinity levels of the water layer
01/Aug/2010
In the State of Rio Grande do Sul, Brazil, flooded rice fields using Patos Lagoon as the source of water for irrigation are subject to be damaged by salinity, since this source is bound to the sea on its southern end. The sensitivity of rice is variable during plant development, being higher in the seedling and reproductive periods. However, there is not enough information about the behavior of plants under salt stress during the course of its development, especially in […]
Restoration of the soil structure by crop sequences established in no-till, as related to water erosion in distinct surface physical conditions
01/Aug/2010
Soil structure plays a prominent role in plant growth and erosion control, and consequently in food production and soil and water conservation. This research was developed with the objective of implementing and accompanying the restoration process of the structure of a degraded soil, by planting crop sequences under no-tillage (autumn-winter and spring-summer, grass and legume, in single and intercropped systems), and later verifying the relations with water and soil losses caused by rainfall erosion, under distinct surface physical conditions (untilled […]