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Golombieski,Jaqueline Ineu; Marchesan,Enio; Camargo,Edinalvo Rabaioli; Salbego,Joseânia; Baumart,Joele Schmitt; Loro,Vania Lucia; Machado,Sérgio Luiz de Oliveira; Zanella,Renato; Baldisserotto,Bernardo. |
Sublethal adverse effects may result from exposure of aquatic organisms to insecticides at environmentally relevant concentrations. Fingerlings of the common carp (Cyprinus carpio, Linnaeus, 1758), grass carp (Ctenopharyngodon idella, Valenciennes, 1844), and bighead carp (Aristichthys nobilis, Richardson, 1845) were exposed to diafuran, an insecticide widely used during rice cultivation in Southern Brazil. The aim of this study was to verify the relationship between the lethal concentration (LC50) of diafuran and the acetylcholinesterase (AChE) activity in brain and muscle tissues of these species as a possible early biomarker of exposure to this insecticide. LC50 was determined for fish exposed to diafuran concentrations during 96 h (short term): common... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cyprinus carpio; Ctenopharyngodon idella; Aristichthys nobilis; Pesticide; Lethal concentration. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162008000400003 |
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Santos,Rudã F.B.; Dias,Henrique M.; Fujimoto,Rodrigo Y.. |
The objective of this work was to evaluate the acute toxicity of formalin and histopathological effects on the Amazon ornamental fish, bluespotted coridora (Corydoras melanistius). A randomized design was used, with ten concentrations of formalin (40%) (0, 3, 6, 12, 25, 50, 100, 150, 200 and 250mg.L-1) with four replicates and five fish per container (3L) in static system for 96 hours. The moribund fish were killed and fixed in 10% formalin to proceed the histopathological analysis of gill, liver and kidney. At the end of this experiment the following mortality rates (%) were obtained in increasing order of exposure: 0, 0, 0, 0, 0, 65, 85, 100, 100 and 100%. The lethal concentration 50% (LC50-96h (I)) estimated was 50.76 mg.L-1 with regression of y =... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lethal concentration; Corydora; Formaldehyde; Toxicity; Histology; Amazon. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000400014 |
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Spanghero,Diogo Bessa Neves; Spanghero,Emília Carolina Alencar de Medeiros; Pedron,Janaína dos Santos; Chagas,Edsandra Campos; Chaves,Francisco Célio Maia; Zaniboni-Filho,Evoy. |
Abstract: The objective of this work was to evaluate peppermint (Mentha piperita) essential oil toxicity to and potential as an anesthetic for juvenile silver catfish (Rhamdia quelen). To determine the lethal concentration at 4 hours (LC50-4h), 210 fish (3.08±0.8 g and 7.59±0.67 cm) were exposed to 0, 20, 50, 80, 110, and 140 mg L-1 essential oil. To evaluate the anesthetic potential, nine fish were individually exposed to each oil concentration (50, 80, 110, and 140 mg L-1) used. Water quality parameters were controlled. The mortality rate and the severity and extent of the gill injuries of silver catfish juveniles at 4 hours of exposure increased with increasing peppermint essential oil concentrations, with LC50-4h estimated to be 75.06 mg L-1. The main... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mentha piperita; Rhamdia quelen; Anesthesia; Gill; Histology; Lethal concentration. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2019000101102 |
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Maldonado,Alexis; Merino,Loreto; France,Andrés. |
Dalaca pallens (Blanchard) is a pest with great impact on grassland production in Chile. The objective of this research was to evaluate the use of entomopathogenic nematodes (EPN) against D. pallens larvae. Twenty EPN isolates, collected along Chile, were used for nematode selection. The experimental unit consisted of five 50-mL plastic vials filled with Nothofagus dombeyi sawdust and inoculated with 40 dauers per vial. The experimental design was a completely randomized with four replicates per treatment. The results showed that isolate QU N3 (Steinernema australe) and QU N13 (Steinernema unicornum) produced the highest mortality, with 100 and 95% respectively and no differences (P < 0.001) between both. Later, these two isolates were used to calculate... |
Tipo: Journal article |
Palavras-chave: Biological control; Lethal concentration. |
Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000200006 |
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Kengne, Pierre; Charmantier, Guy; Blondeau‐bidet, Eva; Costantini, Carlo; Ayala, Diego. |
Salinity tolerance is an important trait that governs the ecology of disease‐vector mosquitoes by determining their choice of larval habitat, and consequently their ecological and geographical distribution. Here, we used laboratory strains to determine the osmotic responses of larvae of obligate freshwater disease‐vector mosquitoes (Aedes aegypti, Aedes albopictus, Anopheles coluzzii, An. gambiae, Culex pipiens, and Cx. quinquefasciatus) and assessed their relationship with salinity tolerance. First, we analyzed the acute dose–mortality response of fourth‐instar larvae to salinity; then, we measured their hemolymph osmolality after 24‐h exposure to varying salinities. We found that Ae. albopictus was the most tolerant species, followed by An. coluzzii,... |
Tipo: Text |
Palavras-chave: Adaptation; Aedes; Anopheles; Culex; Hemolymph osmolality; Lethal concentration; Mosquitoes; Osmoregulation; Salinity tolerance. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00585/69744/67634.pdf |
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Araújo,Alice M. N. de; Oliveira,José V. de; França,Solange M.; Navarro,Daniela M. do A. F.; Barbosa,Douglas R. e S.; Dutra,Kamilla de A.. |
ABSTRACT This study had the following objectives: to identify and quantify the constituent compounds of essential oils from Cymbopogon winterianus Jowitt, Eucalyptus globulus Labill., Eucalyptus staigeriana F. Muell. ex F.M. Bailey, Foeniculum vulgare Mill., Ocimum basilicum L., Ocimum gratissimum L., and Piper hispidinervum C. DC., investigate their toxicity and repellency to S. zeamais and evaluate the toxicity of P. hispidinervum to immature S. zeamais. Individual tests for each essential oil were conducted with a completely randomized design with five concentrations for each oil and four replicates. Gas chromatography-mass spectrometry revealed the presence of citronellal in C. winterianus, 1,8-cineole in E. globulus, limonene in E. staigeriana,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alternative fumigant; Bioactivity; Lethal concentration; Maize weevil; Natural insecticide. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000500372 |
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Pinheiro,Patricia Valle; Quintela,Eliane Dias; Oliveira,Jaison Pereira de; Seraphin,José Carlos. |
The objective of this work was to determine the most susceptible nymphal stage of Bemisia tabaci biotype B to neem (Azadirachta indica A. Juss.) oil applied to dry bean (Phaseolus vulgaris L.) in a screenhouse. A solution of commercial oil (Dalneem) extracted from neem seeds was sprayed directly on each nymphal instar at 0, 0.1, 0.25, 0.5, 1 and 2% concentrations for lethal concentration (LC) determination, and at 0, 0.5 and 1% concentrations for lethal time (LT) determination. The number of living and dead nymphs was recorded five days after spraying for LC determination, and daily during six days for LT determination. The LC50 estimated for fourth instar nymphs occurred at 0.56% concentration. For all instars, LC50 and LC95 were estimated at 0.32 and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Azadirachta indica; Phaseolus vulgaris; Immature stages; Lethal concentration; Whitefly. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2009000400004 |
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