697 resultados para plantio direto


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia - FEIS

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Soil compaction is one of the limiting factors in areas subjected to direct seeding. The method used to break up the compacted layer should disturb the soil as little as possible, as well as maintain the ground cover. The aim of this study was to evaluate the influence of subsoiling, scarification and use of shaft-type furrowing mechanisms when sowing, on preserving the ground cover, water content and soil density, as well as the effects on maize yield in a dystroferic Red Nitosol, cultivated under a system of direct seeding for ten years. The experimental design was of randomised blocks, with eight soil management treatments: subsoiling to a depth of 0.40 m before sowing the winter crop, subsoiling to 0.40 m before sowing the maize, scarification to 0.30 m before the winter crop, scarification to 0.30 m before the maize, scarification to 0.20 m before the winter crop, scarification to 0.20 m before the maize, direct seeding of the maize with a shaft-type furrowing mechanism and direct seeding of the maize using a double disc furrower. There were four replications. Subsoiling and scarification influenced the preservation of the ground cover, soil density and water content immediately after sowing, but did not interfere in plant development or grain yield in the maize crop. The use of shaft-type furrowing mechanisms in the sowing operation had no effect on any of the parameters under study.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The objective of this work was to evaluate the grass cover crop production in crop systems involving maize and Urochloa ruziziensis, and the influence of topdressing nitrogen rates in the yield and agronomic efficiency on common-bean cultivated in succession in no-tillage. The experiments were conducted in Jaboticabal-SP, in a eutrophic red latosol, in the second year of no-tillage system implementation. The IPR 139 cultivar was used in split plot design with three replications, in randomized block. The plots had been composed for three crop systems in the summer season, with maize exclusive, maize intercropped with U. ruziziensis and U. ruziziensis exclusive. The subplots had been constituted for five nitrogen rates (0, 40, 80, 120 and 160 kg ha(-1)), applied as topdressing at V4-4 in irrigated common-bean cultivated in the winter-spring season. The use of U. ruziziensis in crops systems, exclusive or intercropped with maize favors the grass cover crop production sufficiently to total soli surface covered, possibility similar grain yield compared to maize exclusive. The topdressing nitrogen application doesn't affect the common-bean yield in succession to maize and U. ruziziensis intercropped. The increase of nitrogen rates in common-bean in succession to maize exclusive improves the yield, although decreases the agronomic efficiency.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Agricultura) - FCA

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Agricultura) - FCA

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The soil acidity in no tillage system could be resolved by lime superficial application, improvement to crop mineral nutrition and yield. The experiment carried out on a Rhodic Kandiudalf in Botucatu, São Paulo State, Brazil, in dry conditions, aiming to evaluate the agronomic development and leaf diagnosis of black oat plants, under superficial liming in no tillage system. A randomized complete block design was used, with four replications, the treatments were superficial application of different dolomítico lime rates (R0 = zero – without lime; R1 = 1,8 t ha-1 – lime to increase the base saturation at 50%; R2 = 3,6 t ha-1 – lime to increase the base saturation at 70% and R3 = 5,4 t ha-1 – lime to increase the base saturation at 90%), in October 2002. The black oat Common cultivar was seed in April 2004, in to second year, after the crop rotation of millet (spring) – common bean (summer) – black oat (autumn-winter). The results showed that: the black oat had yield increase by superficial liming, mainly to most dry matter and grain per panicule. Beyond, the superficial liming application did not prejudice leaf diagnosis of culture.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Biodiesel is a reality in Brazil, due to the National Program of Biodiesel Production and Use (PNPB), which became mandatory in 2008 in adding 2% biodiesel in all diesel sold in a blend known as B2. The agribusiness sector responded to the federal program, facing many difficulties in biodiesel production, which highlights the supply of raw material. Problems related to biodiesel production were mainly the shortage of vegetable oil, because of demand from domestic and foreign markets, and rising prices of raw materials available for production, making this biofuel production economically feasible, even in Brazil, where agricultural production costs are among the most competitive in the world. The crambe is a specie that has aroused the interest of Brazilian producers due to oil content, hardiness, and mechanized cultivation, mainly for being a winter crop, it becomes one more option for farmers in this period. In addition, you can compose systems of crop rotation as well as being used as ground cover in winter. The aim of this study was to evaluate the potential for productive and cost of production of crambe, conducted in no-tillage system, to compare these parameters with other oil crops such as sunflower, canola and soybean. The trial was conducted in the agricultural year 2008 at the Experimental Farm Lageado belonging to the Faculty of Agronomic Sciences - UNESP, located in Botucatu - SP. The estimated yield was 1.507,05 kg ha-1, resulting in a production of 561,94 liters of oil per hectare. The cost of installation and conduct of crambe per hectare was R$ 875,87, resulting in a cost of R$ 1,56 per liter of oil, the lowest cost among the oilseed crops analyzed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The current paper had as its objective to analyze the precision planter's operational performance according to five different displacement velocities and two types of jumpers for planting no-tillage corn. The utilized experimental delineation consisted of blocks at random with parcels subdivided in factorial scheme 2x5, two types of jumpers (4 and 5 staples) and five different displacement velocities (3.0; 4.5; 5.0; 7.0 e 9.0 km h-1) with four repetitions and by applying the average comparation test, as for the jumpers effects as for the displacement velocities effects, to the significance level of 5%. It was evaluated the data concerned to the longitudinal distribution of plants, average number of days for the emergence of seedlings, initial and final stand of plants, survival indices, mechanical harm on seeds, germination tests and grain production. It was also observed the planter displacement velocity effect of on variables as: longitudinal distribution of plants, average number of days for the emergence of seedlings, initial and final stand of plants, mechanical harm and yield. The survival indice of plants were high for all the studied velocities and jumpers. Among the studied velocities, the one of 5.0 km h-1 presented the highest yield to both types of jumpers.