|
|
|
| Registros recuperados: 255 | |
|
|
| PIASECKI,C.; MAZON,A.S.; MONGE,A.; CAVALCANTE,J.A.; AGOSTINETTO,D.; VARGAS,L.. |
| ABSTRACT: Glyphosate-resistant hairy fleabane [Conyza bonariensis (L.) Cronq.] is one of the most important weeds in the world. Among the factors that make this weed species widely distributed in the most diverse environments is the high seed production capacity and dispersal. Hairy fleabane plants not controlled by herbicide application regrowth and overcome crop canopy, use environmental resources, interfere with crops, and complete their life cycle by producing thousands of seeds and replenishing the seed bank. Management strategies that reduce production and viability of hairy fleabane seeds can be adopted within the integrated management to reduce the seed bank and prevent further infestations. In this way, experiments were carried out in a greenhouse... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Conyza bonariensis; Resistance; Integrated weed management; Prevention; Soil seed bank. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100198 |
| |
|
|
| VARGAS,L.; HENCKES,J.R.; GAVA,F.; AGOSTINETTO,D.; CARVALHO,I.R.; RAMOS,R.; RODRIGUES,R.. |
| ABSTRACT: Resistance to herbicides is one of the main factors responsible for weed control failures. Once uncontrolled and stressed, resistant weeds demand a new application of herbicides from different modes of action, which results in higher monetary costs and environmental impact. Knowledge of weed sensitivity levels to herbicides before making decisions for their management in the field is paramount to increasing the efficiency of integrated weed management. Thus, methods that allow the rapid determination of sensitivity levels can help to the correct recommendation before the application, and thus, favor the greater technical, economic and environmental efficiency of weed management. The objective of this work was to validate a rapid method to detect... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Integrated weed management; Resistance; Control; Efficiency. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100222 |
| |
|
|
| LUCIO,F.R.; BARROSO,A.A.M.; TOLEDO,R.E.B.; PITELLI,R.A.; VICTORIA FILHO,R.. |
| ABSTRACT: Weed interference reduces the productive potential of crops. Among the control methods used, chemical ones occupy a major position. The repeated application of the same mechanism of action selects tolerant plants. Among the species that affect sugarcane, crabgrass is one of them. This study has aimed to know the tolerance of different populations of this species to herbicides inhibiting photosystem II. Three populations were collected, identified and submitted to the application of ametryn and diuron herbicides in ten different doses, and the experiment was conducted in a experimental design of complete randomized blocks with four repetitions in a factorial arrangement of 10 x 3 (10 doses x 3 populations), being one trial for each herbicide.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Digitaria horizontalis; Ametryn; Diuron; Tolerance; Resistance. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100242 |
| |
|
|
| RIZZARDI,M.A.; SCHNEIDER,T.; BIANCHI,M.A.; ROCKENBACH,A.P.. |
| ABSTRACT: Horseweed is an annual cycle weed naturally controlled by the herbicide glyphosate. However, the continued use of this product has selected tolerant and resistant populations. The objective of this study is to analyze the occurrence of horseweed biotypes with a low glyphosate susceptibility in the states of Rio Grande do Sul, Paraná and Mato Grosso do Sul. Seeds of horseweed plants (Conyzaspp.) that survived glyphosate applications were collected in RR soybean crops, totaling 137 samples from 37 municipalities. The seeds of the biotypes were sown, and the plants originated from them, when they reached the stage of four to six leaves, were subjected to a treatment with 1,440ga.e.ha-1 of glyphosate. According to the results, 108biotypes were not... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Conyza bonariensis; Conyza sumatrensis; Conyza canadensis; Resistance; Chemical control. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100290 |
| |
|
|
| GAZOLA,T.; DIAS,M.F.; CARBONARI,C.A.; VELINI,E.D.. |
| ABSTRACT: The objective of this work was to monitor the resistance of sourgrass (Digitaria insularis) to glyphosate in urban areas of the State of São Paulo to understand the spread of resistant biotypes. Three experiments were conducted under greenhouse conditions in a completely randomized design, with four replications. In the first experiment, seven sourgrass biotypes were used, and the control of plants was evaluated at 7, 14, 21, 28, and 35 days after application (DAA) of glyphosate. In the second experiment, the shikimic acid accumulation was quantified at 72 hours after the glyphosate application, and the same evaluations of weed control were performed. In the third experiment, rate-response curves were developed, with glyphosate at rates of 0, 90,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Shikimic acid; Digitaria insularis; EPSPS; Resistance. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100183 |
| |
|
|
| MATTE,W.D.; CAVALIERI,S.D.; PEREIRA,C.S.; IKEDA,F.S.; POLTRONIERI,F.. |
| ABSTRACT: In the current scenario of resistance of weeds to glyphosate in grain and fiber production systems, imidazolinone-resistant soybean is shown as an option in the rotation of biotechnology events and herbicide action mechanisms through the application of [imazapic+imazapyr]. However, due to its persistence in the soil, the herbicide may harm the subsequent crop. The objective of this work was to evaluate the residual activity of the herbicide [imazapic+imazapyr] applied in pre-emergence in soybean cultivation on cotton in succession. The experimental design was a randomized block design with five replicates, using seven concentrations (0; 6.25; 12.5; 25; 50; 100 and 200%) of the recommended dosage of the herbicide [imazapic+imazapyr] ([78,75+26,25]... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glycine max; Gossypium hirsutum; Carryover; Herbicide; Resistance. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100345 |
| |
|
|
| Vargas,L.; Silva,D.R.O.; Agostinetto,D.; Matallo,M.B.; Santos,F.M.; Almeida,S.D.B.; Chavarria,G.; Silva,D.F.P.. |
| The objective of this study was to determine changes in gas exchange and inhibition of EPSPs, based on the accumulation of shikimic acid in horseweed biotypes resistant and sensitive to glyphosate. Two experiments were conducted in a factorial model. The first one evaluated horseweed biotypes (one resistant and one susceptible to glyphosate), and herbicide rates (0 and 1,080 g a.e. ha ¹) applied on the weed. In the second experiment, the horseweed biotypes (susceptible and resistant to glyphosate) were evaluated in five periods as following: 0, 3, 7, 10, and 14 days after herbicide application (DAH). The photosynthetic rate, transpiration, carboxylation efficiency, and water efficiency were determined using an infrared gas analyzer (IRGA), and shikimic... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hairy fleabane; Resistance; Photosynthesis; EPSPs; Shikimic acid. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582014000100017 |
| |
|
|
| Kaspary,T.E.; Lamego,F.P.; Cutti,L.; Aguiar,A.C.M.; Bellé,C.. |
| Chlorophylls and carotenoids are the main photosynthetic pigment in plants. In the weeds, the greatest amount of photosynthetic pigments can result in high competitiveness of the species. The aim of this study was to quantify the content of photosynthetic pigments in biotypes of fleabane (Conyza bonariensis) susceptible and resistant to glyphosate, by two different methods, as well as a correlation between chlorophyll content obtained by portable and classical methodology (extractable chlorophyll). An experiment was conducted in greenhouse and laboratory, 2 x 5 factorial scheme, where factor A was equivalent to biotypes of fleabane (resistant and susceptible to glyphosate) and factor B to developmental stages plants (rosette vegetative I, II and III and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Conyza bonariensis; Chlorophyll; Carotenoids; Resistance. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582014000200020 |
| |
|
|
| Ferreira,E.A.; Galon,L.; Aspiazú,I.; Silva,A.A.; Concenço,G.; Silva,A.F.; Oliveira,J.A.; Vargas,L.. |
| The objective of this work was to evaluate the translocation of glyphosate in C. bonariensis plants resistant and susceptible to that herbicide. The 14C-glyphosate was mixed with commercial gyhphosate (800 g ha-1) and applied on the center of the adaxial face of a third node leaf, using a micro syringe, and adding 10 µL of a solution with specific activity of 1,400 Bq, 45 days after plant emergence. The concentration of the glyphosate translocated in the plant was evaluated at time intervals of 6, 12, 36 and 72 hours after being applied on the application leaf, stem, roots and leaves. Ten hours after treatment application, the distribution of the product in the application leaf, divided into base, center and apex, was also evaluated by measuring the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicides; Radiochemical; Resistance; Translocation. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582008000300020 |
| |
|
| |
|
|
| VARGAS,L.; SCHNEIDER,T.; AGOSTINETTO,D.; BIANCHI,M.A.. |
| ABSTRACT Ryegrass is a weed of annual cycle that is present in winter crops, in orchards and vineyards of the South region of Brazil. The species is normally controlled by the glyphosate herbicide, but the continuous use of this product caused the selection of resistant biotypes. The use of ACCase inhibitor herbicides is the main alternative for the control of this species, but it has not been satisfactory in some places, thus causing suspicion of resistance to this action mechanism. Thus, the objective of this paper was to evaluate the occurrence and geographic distribution of ryegrass biotypes that are resistant to the clethodim herbicide in the state of Rio Grande do Sul. For that, seeds of ryegrass plants that survived the application of clethodim were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lolium multiflorum; Resistance; Chemical control; Acetyl coenzyme A carboxylase. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000200365 |
| |
|
|
| Menezes,V.G.; Kalsing,A.; Mariot,C.H.P.; Grohs,D.S.; Freitas,T.F.S.. |
| Roguing is a practice used to reduce the seed source of red rice escapes to control in Clearfield-rice areas. However, there is great difficulty in performing it in large and heavily infested rice fields. This objective of this work was to evaluate the effects of the use of imazamox herbicide, applied in different rates and times, on plants of Clearfield-rice and red rice. Four experiments were conducted during the 2007/08 and 2008/09 growing seasons, in completely randomized block design and treatments arranged in factorial design, using three replications per treatment. The treatments had increasing rates of imazamox, application times and rice cultivars. The rice cultivars tested were IRGA 417, IRGA 422 CL, Avaxi CL and Puitá INTA CL. The variables... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Oryza sativa; Imazamox; Roguing; Resistance; Prevention. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000400018 |
| |
|
|
| Dun, Zhe; Mitchell, Paul D.. |
| Transgenic plants producing insecticidal protein derived from Bacillus thuringiensis (Bt) have been widely adopted since their commercial introduction in 1996. The widespread adoption of such plants has reduced use of conventional insecticides while attaining yield gains, thus providing economic, environmental and human health benefits. However, the benefits from Bt crops will be reduced or even eliminated if pests develop resistance to these toxins so that Bt crops are less or no longer effective. Although field resistance to Bt crops has not yet been found in the continental U.S., resistance to Bt sprays has been found in diamondback moth and greenhouse populations of cabbage looper. Hence, considerable attention has been devoted to developing management... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Resistance; Bio-tech; Sustainable; Agricultural and Food Policy; Crop Production/Industries; Environmental Economics and Policy. |
| Ano: 2011 |
URL: http://purl.umn.edu/103581 |
| |
|
|
| Livingston, Michael J.; Storer, Nicholas P.; Van Duyn, John W.; Kennedy, George G.. |
| We examine producer behavior, resistance evolution, and returns under alternative refuge requirements in an eastern North Carolina region with multiple corn, cotton, and soybean fields infested by a mobile pest. Returns are highest, pyrethroid sprays occur least frequently, and pyrethroid resistance evolution is delayed most effectively with no refuge requirement. Complying with the current 20% refuge requirement costs the producer $8.67 per cotton acre, or $34.21 per non-transgenic insecticidal (Bt) cotton acre. Returns are highest under each refuge requirement when one-toxin Bt cotton is not phased out; however, removal of the technology at the earliest phase-out date minimizes regional pyrethroid sprays. |
| Tipo: Journal Article |
Palavras-chave: Bollworm; Bt cotton; Pyrethroids; Resistance; Structured refuge; Unstructured refuge; Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies; Q16; Q56; Q57; Q58; R34; R38. |
| Ano: 2007 |
URL: http://purl.umn.edu/6619 |
| |
|
|
| Miller, Gay Y.; Algozin, Kenneth A.; McNamara, Paul E.; Bush, Eric J.. |
| Public health experts are concerned about the diminishing efficacy of antibiotics. Some have called for a ban on growth-promoting antibiotics in animal agriculture. This study identifies the contribution of growth-promoting antibiotics in the grower/finisher phase of U.S. pork production. With National Animal Health Monitoring System swine data, relationships are estimated between growth-promoting antibiotic use and productivity. Results indicate improvements in average daily gain (0.5%), feed conversion ratio (1.1%), and mortality rate (reduced 0.22 percentage points); these productivity improvements translate into a profitability gain of $0.59 per pig marketed, or an improvement of 9% in net profits associated with growth promotion antibiotics. |
| Tipo: Journal Article |
Palavras-chave: Antibiotics; Economics; Growth promotants; Productivity; Resistance; Swine; Q12; Q18. |
| Ano: 2003 |
URL: http://purl.umn.edu/43146 |
| |
|
| |
|
| |
|
|
| Aksoy,A; El Kahlout,KEM; Yardimci,H. |
| ABSTRACT Using disinfectants in poultry houses is a common practice to ban the zoonotic pathogens like Salmonella. A major concern in using disinfectants is the emergence of bacteria strains that resist some disinfectants. This phenomenon is manifested in the resistance of some Salmonella serotypes against quaternary ammonium compounds. Such resistance is attributed to qacEΔ1 gene which may be possessed by some Salmonella serotypes. This work aimed to evaluate the resistance of Salmonella serotypes (S. Typhimurium, S. Infantis and S. Entiridis) against different disinfectants (benzalkonium chloride, iodine, gluteraldehyde and hydrogen peroxide). The effect of the disinfectants were evaluated by treatment of the bacteria with different concentrations... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Disinfectants; PCR; Poultry; Resistance; Salmonella. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2020000100301 |
| |
|
|
| Biffi,CP; Stefani,LM; Miletti,LC; Matiello,CA; Backes,RG; Almeida,JM; Neves,GB. |
| Isolates of Salmonella sp (104) from poultry samples were isolated and serotyped where eleven were identified as Salmonella Typhimurium (ST). ST isolates were phenotypically tested by disk diffusion and minimum inhibitory concentration (MIC). Four genes related to enrofloxacin (GyrA, GyrB, ParC and ParE), two to gentamicin (AadA and AadB) and two to ceftiofur (BlaCMY-2 and AmpC) resistance were searched by PCR. Our results showed ST resistance to all three antibiotics tested (18.1% for ceftiofur, 45.4% for gentamicin, and 18.1% for enrofloxacin) according to the diffusion test. In the MIC test, the ST isolates showed higher levels of resistance (27.2% for ceftiofur, 54.5% for gentamicin, and 18.2% for enrofloxacin). Three resistance genes out of four... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antimicrobial; Gene; Resistance; Salmonella. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2014000200013 |
| |
|
|
| Colares,Tatiane; Dionello,Rafael G.; Radunz,Lauri L.. |
| ABSTRACT Rice (Oryza spp.), the most important cereal in the world, is grown and consumed in all continents. Brazil is among the top ten producing countries. Stored grains can be attacked by pests (rodents, insects, fungi and mites) that cause serious qualitative and quantitative losses. Because of these losses, one way to alleviate the problem caused by insects during rice storage is the use of resistant materials (grains). Thus, the aim of this study was to evaluate grains from nine different genotypes of rice, in order to identify the existence of materials less susceptible to the attack of Sitophilus zeamais, during 180 days of storage. The mean time of biological cycle (days), susceptibility index (IS) and the number of weevils emerged were evaluated.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Resistance; Rice genotypes; Storage; Weevil. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000300275 |
| |
| Registros recuperados: 255 | |
|
|
|
