0000000001299163
AUTHOR
M. Dolores Garcerá
Relationship between esterase activity and acrinathrin and methiocarb resistance in field populations of western flower thrips, Frankliniella occidentalis.
The western flower thrips, Frankliniella occidentalis (Pergande), is a serious pest in the south-east of Spain owing to its direct feeding on crops, transmission of the tomato spotted wilt virus and its very high level of resistance to insecticides. Mechanisms of resistance were examined using field populations of F. occidentalis with different susceptibilities to acrinathrin, methiocarb (selective insecticides), endosulfan, metamidophos and deltamethrin (broad-spectrum insecticides). Esterase activity towards alpha-naphthyl acetate and p-nitrophenyl acetate in resistant strains was significantly higher than in the reference strain (MLFOM) for both model substrates. This higher activity was…
Differences in the midgut proteolytic activity of twoHeliothis virescens strains, one susceptible and one resistant toBacillus thuringiensis toxins
The development of resistance to Bacillus thuringiensis toxic proteins is a growing concern because it could threaten both conventional and gene transfer use of this environmentally safe biological insecticide. The most common mechanism of resistance involves changes in binding affinity of toxin receptors in the insect midgut membrane. This has not been the case in Heliothis virescens. We have investigated changes in midgut proteolytic activity as a possibility to explain the resistance observed in this insect species. We have developed an improvement of known methods to demonstrate proteolytic activity in crude extracts. Using this method we have found differences in the proteolytic activi…
Sequiterpene-related compounds as endocrine disrupters in Oncopeltus fasciatus, and potential reduced glutathione synthesis modifiers
Sesquiterpene lactones have been found to exhibit effects on insect growth and development. In this study, the bioactivity of natural lactones extracted from Centaurea mariolensis and some structurally related synthetic derivatives has been investigated. Assays have also been carried out in order to determine the potential of these lactones as modifiers of reduced glutathione (GSH) synthesis.
Esterase isoenzymes and insecticide resistance in Frankliniella occidentalis populations from the south-east region of Spain.
BACKGROUND:Frankliniella occidentalis (Pergande) is among the most important crop pests in the south-east region of Spain; its increasing resistance to insecticides constitutes a serious problem, and understanding the mechanisms involved is therefore of great interest. To this end, F. occidentalis populations, collected from the field at different locations in south-east Spain, were studied in terms of total esterase activity and esterase isoenzyme pattern. RESULTS: Individual thrips extracts were analysed by native polyacrylamide gel electrophoresis (PAGE) and stained for esterase activity with the model substrate α-naphthyl acetate. Significant correlations were found between resistance t…
Evaluation of metabolic detoxifying enzyme activities and insecticide resistance inFrankliniella occidentalis
The western flower thrips Frankliniella occidentalis (Pergande) is a very significant pest of a number of different agricultural crops in the south-east of Spain. The importance of thrips as a pest is not due mainly to the direct damage inflicted on the plant, but to the loss in commercial value which occurs as a consequence of the development of dark spots caused by the tomato spotted wilt virus (TSWV) which they transmit. The economic threshold is therefore almost zero, which enhances the problems of resistance management. The present work is part of a global project that attempts to evaluate the status of insecticide resistance in field populations of thrips obtained from several agricul…
Gold-nanoparticles ingestion disrupts reproduction and development in the German cockroach.
The present work shows the effects of gold nanoparticles (AuNPs) orally administered on reproduction and development of the insect Blattella germanica. Newly emerged females were provided with food containing AuNPs (87.44μg/g) of a size between 15 and 30nm (mean 21.8nm), and were allowed to mate with males. Food ingestion, mortality, reproductive parameters (time to ootheca formation and eclosion, ootheca viability and fertility) as well as postembryonic developmental parameters of the first ootheca (nymphal survival and life span) were recorded throughout the experiment. Gold from AuNPs was accumulated by adults of B. germanica with a bioaccumulation factor of 0.1. Ingestion of AuNPs did n…
Silica Nanoparticles for Insect Pest Control.
To date, control strategies used against insect pest species are based on synthetic insecticide applications. In addition, the efficacy of these treatments could be decreased due to insecticide resistance in insect populations. Also, the irrational use of chemical control strategies has negative consequences of non-target organisms and threatening human health. Designing nanomaterial for pest insect control is a promising alternative to traditional insecticide formulations. In particular, it has been proven that silica nanoparticles have the potential for molecules delivery, release control improvement and also their toxicity as insecticide alone. In this work, we summarized the state of kn…
Estudio del efecto del tratamiento con hormonal juvenil en nifas de insectos
En esta práctica analizan las alteraciones producidas en la metamorfosis de insectos por diferentes compuestos con actividad mimética de la hormona juvenil, estudiando simultáneamente la diferente sensibilidad de las especies utilizadasproduccion: Departamento Biología Funcional
Efecto de la temperatura sobre el consumo de oxigeno en animales acuaticos
Frecuencia cardiaca en Daphnia magna: Relación con la temperatura.
Se determina el efecto de la temperatura sobre la frecuencia del latido cardiaco en Daphnia magna, a través de la determinación de la Q10 y la representación de Arrheniusproduccion: Departamento Biología Funcional
Actividad osmorreguladora en branquias de Artemia
Demostración de la existencia de zonas especializadas en el transporte de cloruro en Artemia parthenogenética.produccion: Departamento Biología Funcional
Electromiografía II
Se estudia el reclutamiento y la fatiga muscular mediante la determinación de la fuerza máxima de ambas manos, la observación y el registro del reclutamiento de unidades motoras y el registro de la potencia muscular durante la fatigaproduccion: Departamento Biología Funcional
Electromiografia
Estudio del ciclo estral en el ratón albino
En esta práctica se muestra como reconocer las diferentes fases del ciclo estral del ratón hembra, a partir de la observación de los tipos de células presentes en el exudado vaginal.produccion: Departamento Biología Funcional