Intercropping of corn and Urochloa ruziziensis and the effect of this system of production in the soybean crop in rotation [Consórcio de milho com Urochloa ruziziensis e os efeitos na cultura da soja em rotação]
Correia N.M.,Sao Paulo State University |
Leite M.B.,Sao Paulo State University |
Bioscience Journal | Year: 2013
This work aimed to study the intercropping of corn and Urochloa ruziziensis cv. Common, regarding to vegetative growth and corn yield, capacity of production of forage dry matter, the infestation of weeds and the effect of this system of production in the soybean crop in rotation. Two forms of sowing (hand-sowing and on-line sowing) of U. ruziziensis, four amounts of seeds (200, 400, 600 e 800 points of cultural value, PCV = quantities of seeds x cultural value) and one treatment additional with the single corn were studied. The intercropping did not affect negatively the vegetative growth and corn yield when compared to the single corn. The sowing of 200 PCV of U. ruziziensis seeds, hand-sowed and on-line sowed to 22 days after of sowing of the corn was enough for the maintenance of adequate amount of straw on the soil. At the moment of the harvest of the corn, the dry matter of weed reduced with the increase of the amount of U. ruziziensis seeds and was bigger when the forager was hand-sowed. In the soybean crop in rotation, the density and dry matter of weed reduced linearly with the increase of the amount of U. ruziziensis seeds used in the first year of the research. The intercropping of corn and U. ruziziensis in the first year of the experiment benefited the plants population, plants height and yield of soybean when compared to the monoculture of corn in the same period.
Bernardi A.C.C.,Embrapa Pecuaria Sudeste Soil Fertility |
Mota E.P.,University of Sao Paulo |
Cardosa R.D.,UNICASTELO |
Monte M.B.M.,CETEM |
Oliveira P.P.A.,Embrapa Pecuaria Sudeste
Communications in Soil Science and Plant Analysis | Year: 2014
Nitrogen (N) loss by ammonia (NH3) volatilization is the main factor for poor efficiency of urea fertilizer applied to the soil surface. Losses can be suppressed by addition of zeolite minerals to urea fertilizer. The objective of this study was to evaluate ammonia volatilization from soil and dry-matter yield and nitrogen levels of Italian ryegrass. A greenhouse experiment was carried out with the treatments of urea, urea incorporated into soil, urea + urease inhibitor, urea + zeolite, ammonium nitrate, and unfertilized treatment. Ammonia was captured by a foam absorber with a polytetrafluoroethylene tape. There were few differences between zeolite and urease inhibitor amendments concerning NH3 volatilization from urea. Results indicate that zeolite minerals have the potential to improve the N-use efficiency and contributed to increasing N uptake. Zeolite and urea mixture reduced 50% the losses by volatilization observed with urea. © 2014 Taylor and Francis Group, LLC.
Productivity, physiological quality and chemical composition of crambe seeds in different doses of phosphorus [Produtividade, qualidade fisiológica e composição química de sementes de crambe em diferentes doses de fósforo]
Vazquez G.H.,Sao Paulo State University |
Lazarini S.,University Camilo Castelo Branco |
Camargo F.P.,University Camilo Castelo Branco |
Ferreira R.B.,Sao Paulo State University |
Bioscience Journal | Year: 2014
The crambe is a brassica with high content of oil used for biodiesel production and that has aroused interest in the short cycle and low production cost. However, there are doubts about their response to phosphated fertilization. The objective of this study was to evaluate the effect of different doses of phosphorus on yield, physiological quality, chemical composition and oil content of crambe seeds. The treatments consisted of five doses of phosphorus (0, 25, 50, 75 and 100 kg ha-1) applied at sowing. There was no effect of phosphorus on mineral composition and oil content of the seeds of crambe that showed the following averages: 30.11 N, 7.46 P, 7.35 K, Ca 10.06, 6.58 mg and 8.98 g kg-1 S; 36.25 Cu, Fe 169.40, 36.75 Mn 73.60 mg kg-1 Zn and 30.22 oil. It was concluded that the productivity of crambe increases with phosphorus rates of up to 100 kg ha-1, but its use does not affect the survival rate of plants, dry mass, the mass of thousand seeds, the physiological quality, chemical composition and oil content of the seed.
Chiarelli-Neto O.,University of Sao Paulo |
Pavani C.,University of Sao Paulo |
S. Ferreira A.,University of Sao Paulo |
Uchoa A.F.,UNICASTELO |
And 2 more authors.
Free Radical Biology and Medicine | Year: 2011
We have studied the spectroscopic properties of hair (white, blond, red, brown, and black) under illumination with visible light, giving special emphasis to the photoinduced generation of singlet oxygen ( 1O 2). Irradiation of hair shafts (λ ex > 400 nm) changed their properties by degrading the melanin. Formation of C3 hydroperoxides in the melanin indol groups was proven by 1H NMR. After 532-nm excitation, all hair shafts presented the characteristic 1O 2 emission (λ em = 1270 nm), whose intensity varied inversely with the melanin content. 1O 2 lifetime was also shown to vary with hair type, being five times shorter in black hair than in blond hair, indicating the role of melanin as a 1O 2 suppressor. Lifetime ranged from tenths of a nanosecond to a few microseconds, which is much shorter than the lifetime expected for 1O 2 in the solvents in which the hair shafts were suspended, indicating that 1O 2 is generated and suppressed inside the hair structure. Both eumelanin and pheomelanin were shown to produce and to suppress 1O 2, with similar efficiencies. The higher amount of 1O 2 generated in blond hair and its longer lifetime is compatible with the stronger damage that light exposure causes in blond hair. We propose a model to explain the formation and suppression of 1O 2 in hair by photosensitization of melanin with visible light and the deleterious effects that an excess of visible light may cause in hair and skin. © 2011 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Vanzela L.S.,UNICASTELO |
Grecco D.L.G.,Fernandopolis SP |
Da Costa Neto J.N.,Fernandopolis SP |
Santos G.O.,Sao Paulo State University
Engenharia Agricola | Year: 2014
The siltation is a natural process, but can be accelerated by human actions and results in major problems for the reservoirs, reducing its useful volume for irrigation. An example of this problem was the reduction of the area of mirror water of Fernandópolis municipal dam in 48.3% during 20 years. Therefore, this study aimed to evaluate the production of sediments and siltation of Fernandópolis municipal dam from a methodology that can be applied to small earth dams for agricultural purposes. For this, it was monitored, monthly throughout the year, the volume of sediment deposited in the reservoir. The percentage of retention sediment in Fernandópolis municipal dam ranged from 53.9 to 94.5%, that associated with a high specific sediment yield, will cause its full silting in at most 57 years. It is recommended to minimize this process the restoration of permanent preservation areas and the removal of 17,500 m3 of sediment from the riverbed of the dam.