RESUMEN
The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is an important pest of field crops, fruit orchards, commercial vegetables, ornamental plants, and home vegetable gardens. Pheromone-baited traps designed to attract, trap, and kill H. halys are marketed for use in home gardens to reduce damage to plants. To test this assertion, we conducted the following experiment: One group of 15 gardeners placed stink bug traps at the end of a row of tomatoes, Solanum lycopersicum (L.), in their vegetable garden and another group of 14 placed no traps in their garden and served as controls. Gardeners with traps were no more or less likely to have H. halys on tomato plants than those without traps, but the abundance of H. halys on tomato fruits was marginally greater in gardens with traps. However, tomato fruits grown in gardens with traps sustained significantly more injury than tomato fruits grown in gardens without traps. Furthermore, tomato fruits on plants near the trap housed more H. halys than tomato fruits on plants at the end of a row away from the trap. Traps may be useful in identifying gardens where H. halys is likely to be found and ones in which stink bug injury to tomatoes is likely. We found no evidence that stink bug traps protected tomatoes from H. halys, and it appears that the addition of traps to gardens may increase injury to tomato fruits.
Asunto(s)
Conducta Apetitiva/fisiología , Hemípteros/fisiología , Interacciones Huésped-Parásitos/fisiología , Control de Insectos/métodos , Solanum lycopersicum/parasitología , Agricultura , Animales , Solanum lycopersicum/crecimiento & desarrollo , Maryland , Dinámica PoblacionalRESUMEN
The vertebrate hosts of 672 blood-engorged Culex quinquefasciatus Say, collected in Harris County, Texas, during 2005, were identified by nucleotide sequencing PCR products of the cytochrome b gene. Analysis revealed that 39.1% had acquired blood from birds, 52.5% from mammals, and 8.3% were mixed avian and mammalian blood meals. Most frequent vertebrate hosts were dog (41.0%), mourning dove (18.3%), domestic cat (8.8%), white-winged dove (4.3%), house sparrow (3.2%), house finch (3.0%), gray catbird (3.0%), and American robin (2.5%). Results are interpreted in conjunction with concurrent avian and mosquito West Nile virus (WNV) surveillance activities in Harris County. We conclude that Cx. quinquefasciatus is an opportunistic feeder and principal mosquito vector of WNV in this metropolitan area; however, transmission by other mosquito species or by other modes of infection, such as ingestion, must account for the high WNV infection rates among local blue jays and American crows.
Asunto(s)
Culex/virología , Insectos Vectores/virología , Fiebre del Nilo Occidental/transmisión , Virus del Nilo Occidental/aislamiento & purificación , Animales , Aves/virología , Gatos/virología , Perros/virología , Conducta Alimentaria , Control de Mosquitos , Texas , Fiebre del Nilo Occidental/prevención & controlRESUMEN
West Nile virus (WNV) was detected in 11 dead birds and two mosquito pools collected in east Texas and southern Louisiana during surveillance studies in the winter of 2003 to 2004. These findings suggest that WNV is active throughout the year in this region of the United States.
Asunto(s)
Enfermedades de las Aves/epidemiología , Estaciones del Año , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/aislamiento & purificación , Animales , Enfermedades de las Aves/virología , Culex/virología , Insectos Vectores/virología , Louisiana/epidemiología , Control de Mosquitos , Passeriformes/virología , Texas/epidemiología , Factores de Tiempo , Fiebre del Nilo Occidental/epidemiologíaRESUMEN
The sensitivity of the VecTest antigen-capture and RT-PCR assays were compared to brain tissue culture in Vero cells for the detection of WNV in a sample of dead birds collected in East Texas and southern Louisiana during the summer of 2003. Cell culture was used as the gold standard, because it yielded the most positives. Direct culture of brain tissue and the WNV antigen-capture assay, done on oropharyngeal swabs, gave statistically comparable results (46% and 40% positive, respectively). In contrast, RT-PCR done on brain homogenates was significantly less sensitive than direct tissue culture (33% compared to 46%, respectively). Results indicated that RT-PCR may not be consistently the most sensitive assay for detection of WNV in dead bird brain tissue and that the VecTest antigen-capture assay has a number of advantages over the other two detection techniques for routine surveillance activities.