Search results for "tefl"
showing 5 items of 25 documents
Variation in mortality among populations is higher for pymetrozine than for imidacloprid and spiromesifen inTrialeurodes vaporariorumin greenhouses i…
2014
BACKGROUND Insecticide resistance in Trialeurodes vaporariorum W. is unknown in the species' northern distribution range where it inhabits mainly commercial greenhouses. Resistance development in whiteflies feeding on year-round crops in greenhouses is possible owing to the use of chemical treatments to back up biocontrol. The authors tested the response levels to spiromesifen, pymetrozine and imidacloprid in whiteflies collected from seven greenhouses within a 35 km radius in western Finland. RESULTS All except one (PR) population had LC50 values below the recommended concentrations for the tested compounds. However, some populations showed reduced susceptibility to pymetrozine in comparis…
To B or Not to B: Comparative Genomics Suggests
2018
Insect lineages feeding on nutritionally restricted diets such as phloem sap, xylem sap, or blood, were able to diversify by acquiring bacterial species that complement lacking nutrients. These bacteria, considered obligate/primary endosymbionts, share a long evolutionary history with their hosts. In some cases, however, these endosymbionts are not able to fulfill all of their host's nutritional requirements, driving the acquisition of additional symbiotic species. Phloem-feeding members of the insect family Aleyrodidae (whiteflies) established an obligate relationship with Candidatus Portiera aleyrodidarum, which provides its hots with essential amino acids and carotenoids. In addition, ma…
The role of agroecosystems for invasion of a generalist herbivore
2014
Preconditioning of the generalist herbivore Trialeurodes vaporariorum to greenhouse monocultures and its subsequent performance on wild polycultures
2016
Generalist herbivores can face many challenges when choosing their host plant. This can be particularly difficult if their choice and performance are affected by host experience. Greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae), is an invasive generalist herbivore, which has established in year-round greenhouses at northern latitudes where it cannot overwinter outdoors. It mainly uses crops such as cucumber (Cucumis sativus L.), tomato (Solanum lycopersicum L.), and ornamentals as host plants. However, every summer the insect escapes greenhouses and is exposed to natural vegetation. We evaluated the performance of T. vaporariorum on diverse vegetation outside…
Teaching English as a foreign language in accordance with social-constructivist pedagogy
2013
RESUMEN: Este artículo postula que la enseñanza de una Lengua Extranjera (en este caso, del inglés) implica un obstáculo lingüístico que, si no se negocia de forma adecuada, puede hacer esta una tarea contradictoria con los principios básicos de la pedagogía socio-constructivista. Tras identificar este obstáculo y descartar algunas potenciales soluciones, el artículo recurre a los avances didácticos desarrollados en la Enseñanza del Inglés como Segunda Lengua durante las últimas dos décadas, un área ha permanecido más atenta a la naturaleza conflictiva de las interacciones sociales. A partir de este análisis, el artículo extrae algunos ejemplos de la literatura reciente para derivar un mode…