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Farnese F.S.,Federal University of Vicosa | Oliveira J.A.,Federal University of Vicosa | Farnese M.S.,Centro Universitario Of Formiga | Gusman G.S.,Federal University of Vicosa | And 2 more authors.

Arsenic (As) is the one of the main environmental pollutant and phytoremediation is an effective tool for its removal of the environment. In this study, Pistia stratiotes were exposed to seven As concentrations (0, 3, 7, 10, 13, 16 and 20 μM) and then, the influence of this metalloid on growth, mineral nutrition and photosynthesis were analyzed. It was observed that this species have a high affinity for As and pollutant uptake occurs rapidly. The uptake of Cu, Mn, Fe and P increased until the concentration of 13 μM, decreasing in higher concentrations.The Mg content also decreased from this same concentration. No effects were observed in the uptake of K, Ca and Zn. Growth rate and photosynthetic pigments content were negatively affected by As. Despite this decrease, the growth was maintained up to the concentration of 13 μM of As. The maintenance of growth and the change in nutrients uptake are probably related with the increase in antioxidant capacity of the plant, indicating resistance to the pollutant. In this way, P. stratiotes is probably an efficient phytoremediator of As, even when in concentrations up to one hundred times greater than those permitted in water for human consumption. Source

De Castro Ferreira E.,Fundacao Oswaldo Cruz Mato Grosso do Sul | De Sousa A.M.,Minas Gerais State University | Morais M.H.G.,Minas Gerais State University | Rocha A.M.S.,Federal University of Ouro Preto | And 6 more authors.
BioMed Research International

Some epidemiological aspects of leishmaniasis in the municipality of Formiga, Brazil, an important touristic site, were evaluated. Those included phlebotomine sand fly vectors, canine infection, and geoprocessing analysis for determining critical transmission areas. Sand flies (224 insects) belonging to ten different species were captured. The most captured species included Lutzomyia longipalpis (35.3%), Lutzomyia cortelezzii (33.5%), and Lutzomyia whitmani (18.3%). A significant correlation between sand fly densities and climatic conditions was detected. Serological diagnosis (DPP and ELISA) was performed in 570 dogs indicating a prevalence of 5.8%. After sequencing the main species circulating in the area were Leishmania infantum and Leishmania braziliensis. Spatial analysis demonstrated that vegetation and hydrography may be related to sand fly distribution and infected dogs. The municipality of Formiga has proven leishmaniasis vectors and infected dogs indicating the circulation of the parasite in the city. Correlation of those data with environmental and human cases has identified the critical areas for control interventions (south, northeast, and northwest). In conclusion, there is current transmission of visceral and canine human cases and the city is on the risk for the appearance of cutaneous cases. © 2015 Júlia Alves Menezes et al. Source

Pinto D.B.F.,Centro Universitario Of Formiga | Da Silva A.M.,Federal University of Lavras | Beskow S.,Federal University of Pelotas | De Mello C.R.,Federal University of Lavras | Coelho G.,Federal University of Lavras
Transactions of the ASABE

Hydrological models have been increasingly employed for evaluation of pollution caused by diffuse sources in watersheds. In this study, the Soil and Water Assessment Tool (SWAT) was used to simulate streamflow and suspended sediment concentration (SSC) at the Lavrinha Creek watershed (LCW) outlet, which is situated in the Mantiqueira Range region in Minas Gerais State, Brazil. Temporal series associated with climatic variables, streamflow, and SSC were obtained from existing hydrological monitoring that has been conducted in the LCW since January 2006. Eight months (January 2006 to August 2006) were chosen as the warm-up period for the SWAT model, while two years (September 2006 to August 2008) were considered for model calibration and two years (September 2008 to August 2010) for model validation. A statistical index, Nash-Sutcliffe efficiency (NSE), was employed to evaluate the model performance. Streamflow simulations with SWAT on a daily basis resulted in NSE values of 0.81 and 0.79 for the calibration and validation periods, respectively; when simulating sediment concentration, the model resulted in NSE values of 0.68 and 0.75 for the calibration and validation periods, respectively. The SWAT model was considered adequate to simulate streamflow and SSC at the LCW outlet, thus constituting an important tool for water resources management in the Mantiqueira Range region. © 2013 American Society of Agricultural and Biological Engineers. Source

da Silva F.C.,Federal University of Fluminense | da Silva F.M.,Federal University of Lavras | Scalco M.S.,Federal University of Lavras | Sales R.S.,Centro Universitario Of Formiga
Coffee Science

The coffee yield is strongly influenced by adequate supply of water and nutrients to plants. Because not all soil is the ideal amount of nutrients for plant growth, fertilization is intended to supplement these nutrients. The nole of fertigation is to provide coffee the water volume to be supplied with nutrients and preventing entering the plant water stress and nutrition. This study was carried out in the experimental area of the Department of Agriculture, Universidade Federal de Lavras in coffee cultivar Catigua MG 3 plants spaced 2.5 × 0.60 m. We tried to raise the detachment force of fruit maturation in green and cherry fruit moisture, trying to verify if these parameters correlate with the status of plants, over the period of maturation and consequently the selective mechanical harvesting. It was concluded that the oscillations of the detachment force of the coffee cherry are related to variables of the soil. The alterations found in fruit detachment force are observed when changes occur in soil moisture and soil water tension. © 2016, Editora UFLA. All rights reserved. Source

Ribeiro L.R.,Centro Universitario Of Formiga | Ribeiro L.R.,Federal University of Lavras | Santos M.F.,Centro Universitario Of Formiga | Silva Q.M.,Centro Universitario Of Formiga | And 3 more authors.
Biologia (Poland)

Infusions of the leaves and seeds of Annona crassiflora Mart. are commonly employed in the treatment of diarrhoea, snakebites, tumours and disorders of the hair and scalp. The aim of the present study was to investigate the cytotoxic and genotoxic properties of ethanolic extracts of A. crassiflora by evaluating their effects on germination, root elongation, chromosome structure and the cell division of Lactuca sativa (lettuce). The experiment followed a randomized design involving the treatment of L. sativa seeds with ethanolic extracts from leaves and seeds of A. crassiflora applied at ten concentrations (0. 0125, 0. 025, 0. 05, 0. 1, 0. 2, 0. 4, 0. 6, 0. 8, 1. 0, and 1. 2 mg/L) and with five repetitions per treatment. Seeds of L. sativa exposed for 48 h to A. crassiflora leaf extract at concentrations ≥ 0. 1 mg/L, or to seed extracts at concentrations ≥ 0. 2 mg/L, showed germination percentages that were significantly (p < 0. 05) lower than those of seeds exposed to aqueous ethanol control. Exposure of L. sativa seedlings to leaf (but not seed) extracts of A. crassiflora produced significant (p < 0. 05) reductions in the mitotic indices of root meristem cells of lettuce and induced chromosome and nuclear abnormalities in the root cells. The presence of chromosome stickiness, bridges, fragments, laggard chromosomes and nuclear condensation were also observed. The cytogenetic effects observed suggest that folkloric medicines prepared with extracts of the leaves or seeds of A. crassiflora should be employed with caution. © 2013 Versita Warsaw and Springer-Verlag Wien. Source

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