Genotypic variation among Douglas-fir tussock moth nucleopolyhedrovirus (OpNPV) isolates in the western United States.

Periodic outbreaks of the Douglas-fir tussock moth (Orgyia pseudotsugata) in forests of western North America generally end with a sudden collapse due primarily to an epizootic caused by a nucleopolyhedrovirus (NPV) that occurs naturally within O. pseudotsugata populations. We genotypically characterized NPV populations from Washington State, Oregon, Idaho, New Mexico and California for the first time.

In vitro culture of Lambdina fiscellaria lugubrosa nucleopolyhedrovirus in heterologous cell lines.

Infections of two heterologous insect cell lines derived from Malacosoma disstria (Md108) and Choristoneura fumiferana (Cf70) by the Lambdina fiscellaria lugubrosa nucleopolyhedrovirus (LafiNPV-W) were characterized. Cytopathic effects characteristic of LafiNPV-W infection, including rounding of cells, nuclear hypertrophy, and occlusion body (OB) production, were observed in both cell lines. Budded virus titers were slightly higher in Md108 cells than Cf70 cells (5.

Development of a dipstick immunoassay to detect nucleopolyhedroviruses in Douglas-fir tussock moth larvae.

In this paper, we describe the development of a novel field detection system for the identification of Orgyia pseudotsugata nucleopolyhedrovirus (OpNPV) and OpNPV infections in Douglas-fir tussock moth (O. pseudotsugata) (DFTM) larvae, utilizing antibodies in a dipstick immunoassay. The dipstick method is sensitive to a minimum of 10ng of extracted virus protein, or approximately 1070 virus occlusion bodies, and is sufficiently sensitive to detect OpNPV infections in DFTM prior to mortality.

Recovery of nontarget Lepidoptera on Vancouver Island, Canada: one and four years after a gypsy moth eradication program.

The gypsy moth (Lymantria dispar) is a destructive defoliator that is not established in British Columbia, Canada, because of successful eradication programs involving the microbial insecticide Bacillus thuringiensis var. kurstaki (Btk). In 1999, three aerial applications of Btk were made over two areas, totaling 12,805 ha, on southern Vancouver Island, Canada.

Development and evaluation of methods to detect nucleopolyhedroviruses in larvae of the Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough).

Various molecular methods are used to detect pathogenic microorganisms and viruses within their hosts, but these methods are rarely validated by direct comparison. Southern hybridization, enzyme-linked immunosorbent assay (ELISA), and a novel DNA extraction/PCR assay were used to detect Orgyia pseudotsugata multiple nucleopolyhedrovirus (OpMNPV) in Douglas-fir tussock moth larvae. PCR was more sensitive than Southern hybridization and ELISA at detecting semipurified virus.

Genotypic variation and presence of rare genotypes among Douglas-fir tussock moth multicapsid nucleopolyhedrovirus (OpMNPV) isolates in British Columbia.

The Douglas-fir tussock moth (Orgyia pseudotsugata) multicapsid nucleopolyhedrovirus (OpMNPV) is periodically applied to suppress Douglas-fir tussock moth populations in British Columbia and in the western United States. The strain of OpMNPV in the product currently used for suppression is not genetically distinct from naturally occurring OpMNPV. To separate the mortality caused by the applied virus from that caused by the naturally occurring virus, a rare and genetically distinct strain of OpMNPV must be applied.