119 research outputs found
Forms of application of nitrogen in different stages of the development of soybean culture / Formas da aplicação de nitrogênio em diferentes estádios do desenvolvimento da cultura da soja
In Brazil, inoculation with Bradyrhizobium japonicum and B. elkanii strains is the main form of Nitrogen (N) supply to soybean, but there are reports of the use of mineral N as a complement to biological fixation. The objective was to evaluate the effect of different forms and times of N application on the development and yield of soybean. The treatments include a control without N application and in all other treatments 10 kg ha-1 of N was applied, altering the time (V2, V4, R1 or R2) and the application form, namely, at sowing, broadcast on topdressing or by leaf spraying. The application of N provided an increase in leaf area, dry mass of shoot, number of nodules and dry mass of nodules in treatments with application of N at sowing and N at V2 on topdressing. For plant height, the treatment with N at V2 by leaf spraying was superior compared to control. The weight of one thousand seeds was not affected by N application. For grain yield the treatments with application of N by leaf spraying in V2 and R1 were highlighted. The greatest increase in grain yield on soybean is reached with leaf spraying at V2 stage
Management Effect on Rainfall Use Efficiency and Growth Rate of Spineless Cactus \u3cem\u3ecv.\u3c/em\u3e Miúda in Northeast Brazil
Spineless cactus has a high rainfall use efficiency. Under water deficit, they open their stomata during the night to capture atmospheric carbon dioxide when the air temperature is lower and relative humidity higher (Taiz and Zeiger, 2009), losing less water to the atmosphere. The rainfall use efficiency (RUE) can be expressed as the amount of water used by the crop to produce dry matter (Han and Felker, 1997). The RUE showed by spineless cactus, a CAM plant, is three to five times greater than the one observed in C3 and C4 plants (Felker and Russel, 1988; Nobel, 1991). Therefore, spineless cacti (Nopaleae opuntia) are important forage resource in northeast Brazil. Management practices, however, can affect the RUE and growth of spineless cactus, especially organic and mineral fertilization. Thus, the objective of this research was to evaluate the effect of organic and nitrogen fertilization and harvest frequency on rainfall use efficiency and growth rate of spineless cactus cv. Miúda (Nopalea cochenillifera Salm Dyck)
Composição bromatológica e digestibilidade de cana-de-açúcar colhida em duas épocas do ano
Objetivou-se com este estudo avaliar o efeito da época de corte sobre a composição bromatológica e digestibilidade in vitro de genótipos de cana-de-açúcar, comparar a composição bromatológica e digestibilidade in vitro das frações colmo e folhas, e estabelecer possíveis correlações entre composição química e digestibilidade in vitro da planta inteira de genótipos da cana-de-açúcar. Nove genótipos foram colhidos em maio e setembro de 2006. Em maio, somente a fração planta inteira foi analisada, em setembro foram separados em colmos, folhas ou planta inteira para determinação da composição bromatológica, sacarose (POL) e digestibilidade in vitro. Colmos apresentaram menor teor de fibra em detergente neutro (FDN) e lignina na MS, e maior digestibilidade in vitro da matéria seca (DIVMS) do que folhas. Em contrapartida, apresentaram menor digestibilidade in vitro da FDN (DIVFDN), maior teor de lignina na FDN e menor concentração de proteína bruta (PB). Houve redução no teor e digestibilidade da FDN com o avanço da maturidade, enquanto que DIVMS, POL e lignina aumentaram. A DIVMS se mostrou negativamente correlacionada com FDN e FDN/POL, porém não houve correlação entre DIVFDN e FDN ou FDN/POL. Conclui-se que o avanço da maturidade promoveu redução na DIVFDN e aumento na DIVMS, não existindo correlação genética entre acúmulo de açúcar e digestibilidade in vitro da fibra. Os dados deste artigo indicam não ser esperado que a seleção de genótipos com maior DIVFDN do colmo altere o teor de açúcar do mesmo.The objectives of this study were to evaluate the effect of time of harvest on chemical composition and in vitro digestibility of sugarcane genotypes, to compare chemical composition and in vitro digestibility of the stem and leaf fractions, and to determine possible correlations between chemical composition and in vitro digestibility of the whole plant in sugarcane genotypes. Nine genotypes were harvested in May and September of 2006. In May, only the whole-plant fraction was analyzed, in September the genotypes were separated in stems, leaves or whole-plant for determination of chemical composition, sucrose (POL) and in vitro digestibility. Stems had lower neutral detergent fiber (NDF) and lignin in the DM, and greater in vitro dry matter digestibility (IVDMD) than leaves. However, stems had lower in vitro NDF digestibility (IVNDFD), higher lignin in the NDF and lower crude protein (CP). The NDF and IVNDFD were reduced with advanced maturity, while IVDMD, POL and lignin were increased. IVDMD was negatively correlated with NDF and NDF/POL, however there was no correlation between IVFDND and NDF or NDF/POL. It can be concluded that with the advance in maturity the IVNDFD was reduced and IVDMD was increased, and there was no genetic correlation between accumulation of sugar and in vitro fiber digestibility. Data from this study indicate that it is not expected that selection of genotypes with greater stem IVNDFD would alter the sugar content of the plant
Late evaluation of the relationship between morphological and functional renal changes and hypertension after non-operative treatment of high-grade renal injuries
Objective: To evaluate the anatomical and functional renal alterations and the association with post-traumatic arterial hypertension. Methods: The studied population included patients who sustained high grades renal injury (grades III to V) successfully non-operative management after staging by computed tomography over a 16-year period. Beyond the review of medical records, these patients were invited to the following protocol: clinical and laboratory evaluation, abdominal computed tomography, magnetic resonance angiography, DMSA renal scintigraphy, and ambulatory blood pressure monitoring. The hypertensive patients also were submitted to dynamic renal scintigraphy (Tc-99m EC), using captopril stimulation to verify renal vascular etiology. Results: Of the 31 patients, there were thirteen grade III, sixteen grade IV (nine lacerations, and seven vascular lesions), and two grade V injuries. All the patients were asymptomatic and an average follow up post-injury of 6.4 years. None had abnormal BUN or seric creatinine. The percentage of renal volume reduction correlates with the severity as defined by OIS. There was no evidence of renal artery stenosis in Magnetic Resonance angiography (MRA). DMSA scanning demonstrated a decline in percentage of total renal function corresponding to injury severity (42.2 +/- 5.5% for grade III, 35.3 +/- 12.8% for grade IV, 13.5 +/- 19.1 for grade V). Six patients (19.4%) had severe compromised function (< 30%). There was statistically significant difference in the decrease in renal function between parenchymal and vascular causes for grade IV injuries (p < 0.001). The 24-hour ambulatory blood pressure monitoring detected nine patients (29%) with post-traumatic hypertension. All the patients were male, mean 35.6 years, 77.8 % had a familial history of arterial hypertension, 66.7% had grade III renal injury, and average post-injury time was 7.8 years. Seven patients had negative captopril renography. Conclusions: Late results of renal function after conservative treatment of high grades renal injuries are favorable, except for patients with grades IV with vascular injuries and grade V renal injuries. Moreover, arterial hypertension does not correlate with the grade of renal injury or reduction of renal function
Plants population and harvesting times influence in saccharine sorghum BRS 506 production
Saccharine sorghum is an excellent option for ethanol production under industrial and agronomic perspectives, due to high green matter production and succulent stalks with fermentable sugars. The aim of this work was to evaluate the harvesting season and plants population effect over the
ethanol and fodder production from sweet sorghum culture BRS 506. The experiment was installed in November 2012, at (CDTCA/UFLA), located in Lavras (MG). The experimental design was in randomized blocks, with 3 repetitions, factorial scheme 4 x 4 (4 populations: 70, 100, 130 and 160
thousand plants ha-1 ; 4 harvesting seasons: flowering (0 days after flowering (DAF), 10 DAF, 20 DAF and physiological maturity at 40 DAF). The variables evaluated at harvesting: green matter weight (GM), dry matter weight (DM), juice volume (JV), total soluble solids (ºbrix), total reducing sugars (TRS) and brix tonnes per hectare (TBH). The populations increase provided the highest JV and it has not affected other variables. The characteristics were influenced by the harvesting seasons. The harvesting season at 40 DAF provided the highest ºbrix. The ºbrix and the TRS showed linear growth with an increase after flowering for plants harvesting. The highest productivities (GM, DM, JV and TBH) were obtained close to 17, 22, 17 and 14 DAF, respectively, favoring higher fodder and ethanol
production in these stages
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