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| Registros recuperados: 23 | |
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| Quintero,Nathalia; Stashenko,Elena E.; Fuentes,Jorge Luis. |
| In this work, the toxicity and genotoxicity of organic solvents (acetone, carbon tetrachloride, dichloromethane, dimethylsulfoxide, ethanol, ether and methanol) were studied using the SOS chromotest. The influence of these solvents on the direct genotoxicity induced by the mutagens mitomycin C (MMC) and 4-nitroquinoline-1-oxide (4-NQO) were also investigated. None of the solvents were genotoxic in Escherichia coli PQ37. However, based on the inhibition of protein synthesis assessed by constitutive alkaline phosphatase activity, some solvents (carbon tetrachloride, dimethylsulfoxide, ethanol and ether) were toxic and incompatible with the SOS chromotest. Solvents that were neither toxic nor genotoxic to E. coli (acetone, dichloromethane and methanol)... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antigenotoxicity; Genotoxicity; Interference; Mitomycin C; 4-nitro-quinoline-1-oxide; SOS chromotest; Solvents; Vitamin E. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000300018 |
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| Aspiazú,I.; Sediyama,T.; Ribeiro Jr.,J.I.; Silva,A.A.; Concenco,G.; Ferreira,E.A.; Galon,L.; Silva,A.F.; Borges,E.T.; Araujo,W.F.. |
| The objective of this work was to evaluate characteristics associated with the photosynthetic activity of cassava plants under weed competition. The trial was carried out under field conditions, and experimental units consisted of 150 dm³ fiberglass boxes containing red yellow Latosol, previously corrected and fertilized. Treatments consisted in the cultivation of cassava plants which were free of weed competition and associated with three weed species: Bidens pilosa, Commelina benghalensis or Brachiaria plantaginea. After manioc sprouting started, 15 days after being planted, weeds that had been sown when manioc was planted were thinned, there were then eight plants left per experimental unit in accordance with specified treatments: cassava free of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Interference; Bidens pilosa; Commelina benghalensis; Brachiaria plantaginea; Physiological variables. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582010000500004 |
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| Trezzi,M.M.; Balbinot Jr.,A.A.; Benin,G.; Debastiani,F.; Patel,F.; Miotto Jr.,E.. |
| The existence of large areas infested with populations of Conyza spp. resistant to glyphosate in Brazil demands appropriate and integrated management strategies. This experiment aimed to identify soybean cultivars with greater competitive ability with horseweed plants and to determine plant characteristics associated with this ability. The experiment was arranged in a randomized complete block design with split plots. Seven soybean cultivars (CD 225 RR, BRS 232, CD 226 RR, NK 7054 RR, BMX Apollo RR, BRS 245 RR and BRS 255 RR) were allocated in the plots, and two interference situations (absence and 13.3 plants of Conyza m-2, transplanted seven days before soybean planting) in the subplots. The average yield loss due to competition with horseweed was 25%.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Conyza spp.; Interference; Competition; Grain yield. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000300006 |
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| SCHUSTER,M. Z.; PELISSARI,A.; SZYMCZAK,L. S.; LUSTOSA,S. B. C.; MORAES,A.. |
| ABSTRACTWhite clover is tolerant to many herbicides, making difficult a chemical control of this species during soybean crop establishments. The objective of this research was to select herbicides applied postemergence to control white clover in soybean and know the effects of this control on soybean yield. Seven herbicides were assessed, applied postemergence, with or without sequential application of glyphosate, and two control treatments (no control and total control of white clover). Glyphosate (with two sequential applications), fomesafen (with a sequential application of glyphosate), chlorimuron-ethyl and lactofen have shown a satisfactory control of white clover (above 80%). The lower control efficiency has resulted in lower production of soybeans. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicide; Integrated Crop-Livestock System; Interference; Trifolium repens; Glycine max. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582015000300561 |
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| NOGUEIRA,C.H.P.; CORREIA,N.M.. |
| ABSTRACT The objective was to study the selectivity of herbicides bentazon and nicosulfuron, alone and in a mixture, to Crotalaria juncea, when established in intercropping with maize, as well as weed control and maize development in this production system. Two experiments were conducted in the field, in late harvest and in harvest periods. The experimental design was a randomized block, with 14 treatments and four replicates. Eight treatments with herbicides bentazon (720 and 960 g a.i. ha-1), nicosulfuron (16 and 48 g a.i. ha-1) and bentazon plus nicosulfuron (720 + 16; 720 + 48; 960 + 16; 960 + 48 g a.i. ha-1) were studied, besides six controls (single crop maize and sunn hemp, with and without weed control, intercropped maize and sunn hemp, with and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Green manure; Sunn hemp; Phytointoxication; Interference; Simultaneously sowing. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000400747 |
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| Araújo,FC.; Ronchi,C.P.; Almeida,W.L.; Silva,M.A.A.; Magalhães,C.E.O.; Good-God,P.I.V. |
| The aim of this study was to determine the weed strip control (WSC) required for adequate coffee growth after transplanting. A non-irrigated, field-planted (spaced 3.80 x 0.70 m) crop was used. The experimental design was a randomized block, with four replicates. The treatments were arranged in a 9 x 18 split-plot design to test the WSC of 0, 15, 30, 45, 60, 90, 120, 150, and 190 cm, which involved continuously hand-weeding at each side of the coffee row, and 18 coffee growth measurements. Multiple regression analyses were carried out relating to growth-variables as a function of both WSC and growth-evaluation times. Brachiaria decumbens was the main weed accomplishing 88.5% of the total weed dry mass. The minimum width of the WSC increases as the crop... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea arabica; Competition; Interference; Surinam grass; Weed management; Weedy periods. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582012000100015 |
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| DEISS,L.; MORAES,A.; PELISSARI,A.; FRANZLUEBBERS,A.J.; NETO,F.S.; PONTES,L.S.; BARRO,R.S.; SZYMCZAK,L.S.. |
| ABSTRACT Weed competition on soybean (Glycine max) growth and yield was expected to be different when managed in an agroforestry system as compared with sole-cropping without trees. Therefore agronomic practices to control weeds might need to be modified in agroforestry systems. We analyzed weed competition effects on soybean growth, grain yield, and yield components at different distances from 4year-old eucalyptus (Eucalyptus benthamii) in an alley cropping system, as well as in a sole-crop system in southern Brazil. Above-ground soybean biomass was collected throughout the growing season and a logistic function was used to model crop growth. Weed above-ground biomass sampled during the soybean cycle, and grain yield and yield components at the end of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eucalyptus benthamii; Fire; Glycine max; Growth analysis; Interference; Integrated crop-livestock system. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100268 |
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| Aspiazú,I; Sediyama,T; Ribeiro Jr,J.I; Silva,A.A; Concenco,G; Ferreira,E.A; Galon,L; Silva,A.F; Borges,E.T; Araujo,W.F. |
| The objective of this work was to evaluate characteristics associated with the photosynthetic activity of cassava plants in competition with weeds or not. The trial was performed on open environment conditions, with experimental units consisting of fiber glass vases with 150 dm³ filled with Red Yellow Latosol, previously fertilized. Treatments consisted in the cultivation of cassava plants isolated and associated to three weed species (Bidens pilosa, Commelina benghalensis and Brachiaria plantaginea). After cassava shooting, 15 days after planting, a removal of the weeds excess was performed, sown at the time of cassava planting, leaving six plants m-2 of B. pilosa and four plants m-2 of C. benghalensis and B. plantaginea. At 60 days after emergence (DAE),... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bidens pilosa; Commelina benghalensis; Brachiaria plantaginea; Interference. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582010000400001 |
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| HUSSAIN,S.; KHALIQ,A.; BAJWA,A.A.; MATLOOB,A.; AREEB,A.; ASHRAF,U.; HAFEEZ,A.; IMRAN,M.. |
| ABSTRACT: Understanding the weed interference with different sowing times of crop is inevitable for forecasting yield losses by weed infestation and designing sustainable weed management systems. A field experiment was carried out to evaluate the effects of sowing dates (20th November, 10th December) and various little seed canary grass (LCG) infestation levels (10, 20, 30 and 40 plant m-2) on growth and yield of wheat under semiarid conditions. Plots with two natural infestations of weeds including LCG (Unweeded control; UWC) and excluding LCG (UWC-LCG) were maintained for comparing its interference in pure stands with designated densities. A season-long weed-free (WFC) treatment was also run. All the weeds/LCG infestation levels starting from 10 LCG... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Interference; Little seed canary grass; Sowing time; Weeds; Wheat yield losses. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100272 |
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| DURIGON,M.R.; MARIANI,F.; CECHIN,J.; CAMERA,A.S.; VARGAS,L.; CHAVARRIA,G.. |
| ABSTRACT: This work aimed to compare the competitive ability of canola hybrids susceptible (conventional) or resistant to triazine or imidazolinone group herbicides, with turnip. The experiments were conducted in greenhouse, in a completely randomized design, with four replicates. The hybrids Hyola 571CL (resistant to imidazolinone), Hyola 555TT (resistant to triazine), and Hyola 61 (conventional) were used. The treatments consisted of ratios (100:0; 75:25; 50:50; 25:75; 0:100%) of canola and turnip plants. The evaluation was performed 44 days after emergence, determining the leaf área (AF), dry matter of aerial part (MSPA), and stature (EST) of the plants. The competitiveness analysis was performed through diagrams and interpretation of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brassica napus L.; Raphanus sativus L.; Interference; Competitiveness. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100171 |
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| Ronchi,C.P.; Terra,A.A.; Silva,A.A.. |
| The effects of competition of six weed species on growth, nutrient concentration and nutrient content of coffee plant root system under greenhouse conditions were evaluated. Thirty days after coffee seedling transplantation into 12 L pots with soil level area of 6.5 dm². Weeds were transplanted or sowed in these pots, at densities of 0, 1, 2, 3, 4 and 5 plants per pot. The duration of competition (or weedy periods) from weed transplantation or emergence until plant harvesting, at the weed preflowering stage, were (in days): 77 (Bidens pilosa), 180 (Commelina diffusa), 82 (Leonurus sibiricus), 68 (Nicandra physaloides), 148 (Richardia brasiliensis) and 133 (Sida rhombifolia). Dry matter of coffee plants was linearly reduced with increasing B. pilosa and S.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea arabica; Weed density; Interference; Mineral nutrition; Root. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582007000400004 |
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| Silva,C.M.M.; Ferreira,L.R.; Ferreira,F.A.; Miranda,G.V.. |
| Imazapyr has been used to control stump sprouting in stand of Eucalyptus plantations, where herbicide is applied to the tree trunk before cutting. The herbicide is applied exclusively on the stump to be killed, but little is known about the final fate of the molecule. Imazapyr exudation via roots of eucalypt grown in soil as the substrate was evaluated under greenhouse conditions. Different herbicide doses (0.000, 0.375, 0.750, 1.125, 1.500, and 3.000 kg ha-1 a.i.) were applied on the aerial parts of 8-month-old Eucalyptus grandis clonal seedlings, cultivated in pots with 18.0 dm³ of soil. Forty days after this treatment, the eucalypt plants were cut and a lateral opening in the containers was made and the plants inclined 90º, with plants sensitive to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chopper; Eucalyptus grandis; Bioindicators; Interference; Exudates. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582004000100014 |
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| Cerqueira,F.B.; Erasmo,E.A.L.; Silva,J.I.C.; Nunes,T.V.; Carvalho,G.P.; Silva,A.A.. |
| The objective of this study was to evaluate the competitiveness of two cultivars of upland rice drought-tolerant, cultured in coexistence with weed S. verticillata, under conditions of absence and presence of water stress. The experiment was conducted in a greenhouse at the Experimental Station of the Universidade Federal de Tocantins, Gurupi-TO Campus. The experimental design was completely randomized in a factorial 2 x 2 x 4 with four replications. The treatments consisted of two rice cultivars under two water conditions and four densities. At 57 days after emergence, were evaluated in rice cultivars and weed S. verticillata leaf area, dry weight of roots and shoots and total concentration and depth of roots. Was also evaluated in rice cultivars, plant... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spermacoce verticillata; Interference; Oryza sativa. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000200006 |
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| Agostinetto,D.; Fontana,L.C.; Vargas,L.; Perboni,L.T.; Polidoro,E.; Silva,B.M.. |
| Determining the periods of weed competition with crops helps the producer to choose the most appropriate time to use weed control practices. This strategy allows for the reduction of the number of herbicide applications, reducing costs and the environmental impact of pesticides. The objectives were to determine the period before the interference (PBI) of crabgrass (Digitaria ciliaris) competing with flooded rice, the critical period of interference prevention (CPIP) of crabgrass with soybean and the effects of competition on the grains yield and their components. Experiments were conducted with the coexistence of BRS Querência rice cultivar with crabgrass, for periods of 0, 7, 14, 21, 28, 35, and 110 days after emergency (DAE) and Fundacep 53RR soybean... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Digitaria ciliaris; Oryza sativa; Glycine max; Interference. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582014000100004 |
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| GALON,L; FORTE,C.T.; GIACOMINI,J.P.; REICHERT Jr,F.W.; SCARIOT,M.A.; DAVID,F.A.; PERIN,G.F.. |
| ABSTRACT The objective of the study was to evaluate the competitive ability of summer crisp and butterhead lettuce types in coexistence with populations of ryegrass. The experimental design was completely randomized in a factorial 2 x 7 scheme, with four replications. On the A factor the lettuce types (summer crisp and butterhead) were allocated and, on B, the densities of ryegrass (0, 2, 4, 8, 16, 32 and 64 plants per pot). The number of leaves, chlorophyll content, leaf area, green mass and dry mass of the lettuce types and ryegrass were evaluated, and the diameter of the culture stem and the tiller number of the weed were determined. Differences in competitive ability between the lettuce types in competition with ryegrass were found, and butterhead was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Interference; Lactuca sativa; Lolium multiflorum. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000200239 |
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| Reigosa,Manuel; Gomes,Anabele Stefânia; Ferreira,Alfredo Gui; Borghetti,Fabian. |
| In this article, we review allelopathy studies conducted in Brazil or involving plant species that occur in the country. Conceptions and misconceptions associated with allelopathy, as well as some international criteria to be applied in allelopathic research, are presented and discussed. We observed a sharp increase in the number of papers on this subject conducted in Brazil between 1991 and 2010. However, most studies are conducted under laboratory conditions, lack a clear hypothesis or a solid justification, and typically make use of target species that do not co-exist with the donor species under natural conditions. We also found that most studies do not take the additional steps in order to purify and identify the bioactive molecules. We recommend that... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Allelochemicals; Competition; Interference; Phytotoxicity; Weed control. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000400001 |
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| Carvalho, Leonardo Bianco; FCAV; Guzzo, Caio Dória; Universidade Estadual Paulista "Júlio de Mesquita Filho"; Pitelli, Robinson Antonio; Universidade Estadual Paulista "Júlio de Mesquita Filho"; Cecílio Filho, Arthur Bernardes; Universidade Estadual Paulista "Júlio de Mesquita Filho"; Bianco, Silvano; Universidade Estadual Paulista "Júlio de Mesquita Filho". |
| The objective was to evaluate the effects of initial weedy periods on the weed community and on the productivity of direct seeded and transplanted table beet cropping systems. A field trial was conducted at São Paulo State University, Brazil, in a randomized complete block design using a 2 x 13 factorial scheme. Direct seeding and seedling transplanting methods were evaluated within thirteen increasing weekly weedy periods. Weed relative importance was calculated and weed density and weed dry matter accumulation data were analyzed by nonlinear regression as well as beet yield and stand, which were submitted to analysis of variance. Amaranthus viridis, Coronopus didymus, Cyperus rotundus, Digitaria nuda, Galinsoga parviflora and Nicandra physaloides were... |
| Tipo: Experimento de campo |
Palavras-chave: 5.01.02.00-1 Beta vulgaris; Weeds; Interference; Direct seeding; Seedling transplanting Matocompetição Beta vulgaris; Weeds; Interference; Direct seeding; Seedling transplanting. |
| Ano: 2010 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/4649 |
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| Rezaeieh,Alireza D.; Aminpanah,Hashem; Sadeghi,Seyed M.. |
| Pot experiment was conducted in Iran, to evaluate the effect of methanol on competition between rice (Oryza sativa) and barnyardgrass (Echinochloa crus-galli). The experiment was conducted as a randomized complete block design with a factorial treatment arrangement and three replicates. Factors were two aqueous methanol foliar applications (0, and 14% v/v) and five rice: barnyardgrass ratios (100:0, 75:25, 50:50, 25:6, and 0:100). Replacement series diagrams for aboveground dry weight illustrated that 'Shiroudi' was more competitive than barnyardgrass as averaged across methanol foliar applications. When methanol was not sprayed, the lines for 'Shiroudi' and barnyardgrass intersected at 75:25 rice: barnyardgrass ratio, but when methanol was sprayed at 14%... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Barnyardgrass; Interference; Methanol; Rice. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000200879 |
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| Registros recuperados: 23 | |
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