Instituto Federal Do Sul Of Minas Gerais

Machado, Brazil

Instituto Federal Do Sul Of Minas Gerais

Machado, Brazil

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De Albuquerque J.E.,Federal University of Viçosa | Santiago B.C.L.,Federal University of Viçosa | Campos J.C.C.,Federal University of Viçosa | Reis A.M.,Federal University of Viçosa | And 3 more authors.
Journal of the Brazilian Chemical Society | Year: 2013

Photoacoustic spectroscopy was used to obtain optical properties of edible soybean, canola and olive oils as well to evaluate the oil modifications induced by thermal treatment. The normalized photoacoustic signal intensity and its phase were independently measured as a function of wavelength of the radiation source. The oil samples were heated up to the smoke point and then for additional 30 min in order to degrade them. After, the oil samples were cooled down and photoacoustic measurements were conducted in order to obtain the absorption spectra of samples at both degraded and non-degraded conditions. Comparisons between the two conditions indicate that the degraded oil samples exhibited widening of the absorption bands in ultraviolet region of the spectra, relative to the respective non-degraded sample. Also, the peaks of those absorption bands presented a red shift. © 2013 Sociedade Brasileira de Química.


PubMed | Instituto Federal Do Sul Of Minas Gerais, Murdoch University, Federal University of Viçosa and Federal University of Uberlandia
Type: Journal Article | Journal: Anais da Academia Brasileira de Ciencias | Year: 2015

Vegetation and soil properties of an iron-rich canga (laterite) island on the largest outcrop of banded-iron formation in Serra de Carajs (eastern Amazonia, Brazil) were studied along a topographic gradient (738-762 m asl), and analyzed to test the hypothesis that soil chemical and physical attributes play a key role in the structure and floristic composition of these plant communities. Soil and vegetation were sampled in eight replicate plots within each of the four vegetation types. Surface (0-10 cm) soil samples from each plot were analyzed for basic cations, N, P and plant species density for all species was recorded. CCA ordination analysis showed a strong separation between forest and non-forest sites on the first axis, and between herbaceous and shrubby campo rupestre on the second axis. The four vegetation types shared few plant species, which was attributed to their distinctive soil environments and filtering of their constituent species by chemical, physical and hydrological constraints. Thus, we can infer that Edaphic (pedological) factors are crucial in explaining the types and distributions of campo rupestre vegetation associated with ferruginous ironstone uplands (Canga) in Carajs, eastern Amazonia, therefore the soil properties are the main drivers of vegetation composition and structure on these ironstone islands.


Goncalves Netto A.,University of Sao Paulo | Nicolai M.,Agrocon Assessoria Agronomica | Carvalho S.J.P.,Instituto Federal Do Sul Of Minas Gerais | Borgato E.A.,University of Sao Paulo | Christoffoleti P.J.,University of Sao Paulo
Planta Daninha | Year: 2016

This work was carried out in order to evaluate the susceptibility to ALS-inhibiting herbicides of the Brazilian biotype of glyphosate-resistant A. palmeri, considering different chemical groups. For that, four experiments were performed, each with one of the following herbicides: glyphosate, chlorimuron-ethyl, cloransulan-methyl and imazethapyr. In each trial, treatments were organized according to a 2x8 factorial scheme, in which two were the species of Amaranthus (A. palmeri and A. spinosus) and eight were the herbicide rates (16D, 8D, 4D, 2D, D, 1/2D, 1/4D and herbicide absence; being D the commercial rate of each product). For glyphosate, D = 720 g a.e. ha-1; for chlorimuron-ethyl, D = 20 g ha-1; for cloransulanmethyl, D = 30 g ha-1; for imazethapyr, D = 100 g ha-1. Glyphosate was not applied on A. spinosus. In all the trials, the Brazilian biotype of A. palmeri had low herbicide susceptibility, so it was possible to conclude this biotype has ALS-EPSPs multiple resistance. Therefore, considering only ALS-inhibiting herbicides, this population has sulfonilurea-triazolopirimidineimidazolinone cross-resistance. © 2016, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.


Campos L.H.F.,University of Sao Paulo | Mello M.S.C.,University of Sao Paulo | Carvalho S.J.P.,Instituto Federal Do Sul Of Minas Gerais | Nicolai M.,University of Sao Paulo | Christoffoleti P.J.,University of Sao Paulo
Planta Daninha | Year: 2012

This work aimed to evaluate the initial growth of three species of weed considered as emerging problems for sugarcane crop: Neonotonia wightii, Stizolobium aterrimum, and Merremia cissoides. The experiment was arranged in a completely randomized design, with seven treatments and four repetitions for each species studied. Seven growth evaluations (treatments) were carried out every 15 days, totaling a 105 day-cycle, followed by the analysis of the variables, such as leaf area (Af) given in (cm2 per plant). The sampled material was dried in an oven, with the dry mass (g per plant) of the roots (Mr), the shoot (Ma) and total (Mt) being measured. The biomass accumulation observed shows the high ability of S. aterrimum to produce biomass. At the end of the experiment, stabilization of the dry mass of the shoot (Ma) was observed for the three species, followed by the variable total dry mass (Mt) also showing stabilization at the end of the experiment. S. aterrimum presented the highest initial growth rate and total dry mass accumulation, besides the highest leaf area (Af). N. wightii presented slow initial growth, while M. cissoides showed a significant accumulation of total dry mass (Mt), compared with the other species.


Campos L.H.F.,University of Sao Paulo | Mello M.S.C.,University of Sao Paulo | Carvalho S.J.P.,Instituto Federal Do Sul Of Minas Gerais | Nicolai M.,University of Sao Paulo | Christoffoleti P.J.,University of Sao Paulo
Planta Daninha | Year: 2011

This work aimed to evaluate the influence of sowing depth and soil cover conditions on the emergence of Merremia cissoides, Mucuna aterrima and Neonotonia wightii. Two experiments were carried out for each species. In the first experiment, the treatments were arranged in a factorial scheme 4 × 2, considering four sowing conditions (sown in the soil, and without straw;over the straw; under the straw and over the soil; and under the straw and sown in the soil) and two amounts of sugarcane straw (10 and 15 t ha -1). The treatments of the second experiment consisted of five levels of sowing depth (0, 20, 40, 60 and 80 mm). Seedling emergence was evaluated weekly up to 21 days after sowing (DAS). Higher emergence of M. cissoides and N. wightii was identified in the plots without straw and at lower depths of seed allocation in the soil. The species M. aterrima showed higher emergence in all treatments, proving to be highly adapted to the conditions of mechanized harvest and seed allocation.


Carvalho S.J.P.,Instituto Federal Do Sul Of Minas Gerais | Soares D.J.,Monsanto Corporation | Lopez-Ovejero R.F.,Monsanto Corporation | Christoffoleti P.J.,University of Sao Paulo
Planta Daninha | Year: 2015

Two experiments were carried out to evaluate soil persistence of chlorimuron-ethyl and metsulfuron-methyl and phytotoxicity to corn seeded as a succeeding crop. One experiment was conducted with chlorimuron-ethyl applied at 20 g ha-1, and one with metsulfuron-methyl applied at 3.96 g ha-1. Treatments were arranged in a factorial design with two types of soil (sandy and clay), three irrigation regimes (daily, weekly and no irrigation) and four application timings (90, 60 and 30 days before corn seeding, as well as untreated plots). Soil persistence of the herbicides was influenced by water availability, molecule water solubility (leaching potential) and application timings prior to corn seeding. In sandy soil, with adequate water availability, leaching probably had the greatest influence, reducing the persistence of the products, and consequently allowing less time between product application and corn seeding. In clay soil, microbial degradation was probably more important, because it was assumed that the lesser time available for microorganism activity, the lesser the damage was observed for corn, as long as the crop had enough water availability. Metsulfuron-methyl was the least phytotoxic herbicide, possibly as a result of the properties of its molecule and its higher leaching potential. © 2015 Sociedade Brasileira da Ciencia das Plantas Daninha. All Rights Received.


Albinati J.,Federal University of Minas Gerais | Pappa G.L.,Federal University of Minas Gerais | Otero F.E.B.,University of Kent | Oliveira L.O.V.B.,Federal University of Minas Gerais | Oliveira L.O.V.B.,Instituto Federal Do Sul Of Minas Gerais
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

This paper investigates the impact of geometric semantic crossover operators in a wide range of symbolic regression problems. First, it analyses the impact of using Manhattan and Euclidean distance geometric semantic crossovers in the learning process. Then, it proposes two strategies to numerically optimize the crossover mask based on mathematical properties of these operators, instead of simply generating them randomly. An experimental analysis comparing geometric semantic crossovers using Euclidean and Manhattan distances and the proposed strategies is performed in a test bed of twenty datasets. The results show that the use of different distance functions in the semantic geometric crossover has little impact on the test error, and that our optimized crossover masks yield slightly better results. For SGP practitioners, we suggest the use of the semantic crossover based on the Euclidean distance, as it achieved similar results to those obtained by more complex operators. © Springer International Publishing Switzerland 2015.


Carvalho C.A.M.,Instituto Federal Do Sul Of Minas Gerais | Guimaraes R.M.,Federal University of Lavras | Silva T.T.A.,Instituto Federal Do Sul Of Minas Gerais
Revista Brasileira de Sementes | Year: 2012

Thc evaluate the germination and vigor of Coffea arabica L. cv. Catuaí Vermelho IAC 99 seeds, with and without parchment, submitted to physiological conditioning in a solid matrix for different time periods. The experimental design was a 2 x 4 factorial, with physiological conditioning of seeds, with and without parchment, and four conditioning times (0, 4, 8 and 12 days). The seeds were maintained at 30 oC in a solid matrix, with an adjustment of 100% of the water-holding capacity. After conditioning, the parchment of all the seeds was manually removed and the moisture, germination and vigor were evaluated. It was found that the presence of parchment did not influence the conditioning effects on seed quality. Conditioning for time periods of 4 and 8 days did not improve coffee seed quality, but there was loss in germination and vigor with 12 days conditioning.


Machado E.C.R.,Instituto Federal Do Sul Of Minas Gerais | Lima R.S.O.,Instituto Federal Do Sul Of Minas Gerais | Silva A.P.P.,Instituto Federal Do Sul Of Minas Gerais | Marques B.S.,Instituto Federal Do Sul Of Minas Gerais | And 2 more authors.
Planta Daninha | Year: 2014

Availability of basic information on weed biology is an essential tool for designing integrated management programs for agricultural systems. Thus, this study was carried out in order to calculate the base temperature (Tb) of southern sandbur (Cenchrus echinatus), as well as fit the initial growth and development of the species to accumulated thermal units (growing degree days - GDD). For that purpose, experimental populations were sown six times in summer/autumn conditions (decreasing photoperiod) and six times in winter/spring condition (increasing photoperiod). Southern sandbur phenological evaluations were carried out, on alternate days, and total dry matter was measured when plants reached the flowering stage. All the growth and development fits were performed based on thermal units by assessing five base temperatures, as well as the absence of it. Southern sandbur development was best fit with Tb = 12 °C, with equation y = 0,0993x, where y is the scale of phenological stage and x is the GDD. On average, flowering was reached at 518 GDD. Southern sandbur phenology may be predicted by using mathematical models based on accumulated thermal units, adopting Tb = 12 °C. However, other environmental variables may also interfere with species development, particularly photoperiod.


Silva A.P.P.,Instituto Federal Do Sul Of Minas Gerais | Marques B.S.,Instituto Federal Do Sul Of Minas Gerais | Lima R.S.O.,Instituto Federal Do Sul Of Minas Gerais | Machado E.C.R.,Instituto Federal Do Sul Of Minas Gerais | And 2 more authors.
Planta Daninha | Year: 2014

This work was carried out with the objective of evaluating the growth and development of honey weed (Leonurus sibiricus) based on days or thermal units (growing degree days). Thus, two independent trials were developed to quantify the phenological development and total dry mass accumulation in increasing or decreasing photoperiod conditions. Considering only one growing season, honey weed phenological development was perfectly fit to day scale or growing degree days, but with no equivalence between seasons, with the plants developing faster at increasing photoperiods, and flowering 100 days after seeding. Even day-time scale or thermal units were not able to estimate general honey weed phenology during the different seasons of the year. In any growing condition, honey weed plants were able to accumulate a total dry mass of over 50 g per plant. Dry mass accumulation was adequately fit to the growing degree days, with highlights to a base temperature of 10 °C. Therefore, a higher environmental influence on species phenology and a lower environmental influence on growth (dry mass) were observed, showing thereby that other variables, such as the photoperiod, may potentially complement the mathematical models.

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