RESUMO
BACKGROUND: Insects of the order Lepidoptera are among the most destructive global pests, causing billions of dollars in damage annually. A new class of N-arylpyrazole-4-methylpiperidines with potent activity on lepidopteran species has been discovered. RESULTS: In a high-throughput insecticide screen compound 1 was identified to possess modest activity on the lepidopteran insect Plutella xylostella. Optimization of 1 to compound 42 resulted in a compound with excellent activity on Spodoptera exigua, Spodoptera frugiperda, and Helicoverpa zea with median lethal concentrations values of 2.8, 1.4, and 12.5 ppm respectively. Although the mode of action remains unknown, these compounds do not appear to work by many of the known biochemical mechanisms of insect control. CONCLUSION: N-Arylpyrazole-4-methylpiperidines represent a new class of insecticides with excellent activity on a broad spectrum of lepidopteran pests. Studies to date indicate the potential for a novel mode of action; however, the target site is unknown at present. © 2023 Society of Chemical Industry.
Assuntos
Inseticidas , Mariposas , Animais , Inseticidas/farmacologia , Pirazóis/farmacologia , Insetos , Controle de Insetos/métodos , Spodoptera , LarvaRESUMO
BACKGROUND: The leafminer, Phyllocnistis citrella Stainton, reproduces on leaf flush during winter. Deployment of pheromone during winter could suppress moth populations in spring and summer more than a spring application alone. We tested the primary pheromone component of P. citrella, (Z,Z,E)-7,11,13-hexadecatrienal, released gradually over several months from elastomeric dispensers in a citrus grove in 6.4 ha main plots in winter and/or 3.2 ha subplots in spring (834 mg triene ha(-1) ) and evaluated moth catch and leaf mining. RESULTS: After winter treatment, dispensers provided >85% disruption of male moth catch in traps for 37 weeks, and after spring treatment they provided >92% disruption for 26 weeks, but there was only a 12% reduction in leaf infestation in spring. Two applications were no better than only a single application in spring. Disruption of moth catch was weaker in treated plots where traps were placed high (3.1 m) rather than low (1.6 m) in the tree canopy. CONCLUSION: Dispensers provided effective and persistent disruption of male catch in pheromone-baited monitoring traps but were minimally effective in reducing leaf infestation by P. citrella. Winter application of pheromone did not reduce leaf mining in spring compared with spring application alone. Tops of trees may have provided a refuge for mating. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Assuntos
Citrus/parasitologia , Proteção de Cultivos/métodos , Controle de Insetos/métodos , Mariposas , Polienos , Atrativos Sexuais , Animais , Feminino , Masculino , Polienos/administração & dosagem , Estações do Ano , Atrativos Sexuais/administração & dosagemRESUMO
The Japanese beetle, Popillia japonica Newman, has an unusually broad host range among deciduous woody plants, yet it feeds only sparingly, or not at all, on certain species in the field. We evaluated beetles' preference, survival over time and fecundity on eight woody plant species historically rated as susceptible or resistant and, after verifying those ratings, tested whether resistance is correlated with so-called quantitative defense traits including leaf toughness, low nutrient content (water, nitrogen, and sugars), and relatively high amounts of tannins or saponins, traditionally associated with such plants. We further tested whether species unsuitable for Japanese beetles are also rejected by fall webworms, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), the expected outcome if the aforementioned traits serve as broad-based defenses against generalists. Choice tests supported historical resistance ratings for the selected species: tuliptree, lilac, dogwood, and Bradford callery pear were rejected by Japanese beetles, whereas sassafras, cherry plum, Virginia creeper, and littleleaf linden were readily eaten. Rejected species also were unsuitable for survival over time, or egg-laying, indicating beetles' inability to overcome the resistance factors through habituation, compensatory feeding, or detoxification. None of the aforementioned leaf traits was consistently higher or lower in the resistant or susceptible plants, and plant species rejected by Japanese beetles often were not rejected by fall webworms. Specialized secondary chemistry, not quantitative defenses, likely determines the Japanese beetle's dietary range among deciduous woody plant species it may encounter.
Assuntos
Besouros/fisiologia , Preferências Alimentares , Interações Hospedeiro-Parasita , Característica Quantitativa Herdável , Árvores/parasitologia , Animais , Feminino , Frutose/análise , Glucose/análise , Masculino , Mariposas/fisiologia , Nitrogênio/análise , Folhas de Planta/química , Saponinas/análise , Sacarose/análise , Taninos/análise , Árvores/química , Árvores/genética , Vitaceae/química , Vitaceae/genética , Vitaceae/parasitologia , Água/análiseRESUMO
OBJECTIVE: The purpose of this study was to determine whether knowledge of resident's identity affects the evaluation of surgical skills. STUDY DESIGN: During an objective structured assessment of technical skills, 33 residents in obstetrics and gynecology who performed 10 surgical skills were videotaped with two digital cameras simultaneously. One camera videotaped "hands only," concealing resident identity; the other camera videotaped from the "waist up," revealing identity. Residents wore opaque gowns and gloves. Four faculty reviewers with previous clinical experience with the residents scored the "hands only" videos first. The scoring was based on the total of a global rating scale and a task-specific checklist. RESULTS: The combined scores for all reviewers was significantly different between the two views (P=.03). When the video tapes were analyzed individually, two reviewers scored the views differently; one reviewer scored higher, whereas the other reviewer scored lower. CONCLUSION: Bias can occur in evaluation of surgical skills but is dependent on the individual reviewer. Resident identification can alter the score, depending on the evaluator.