Wolbachia are intracellular bacteria that occur in an estimated 20% of arthropod species. They are of broad interest because they profoundly affect the reproductive fitness of diverse host taxa. Here we document the apparent ubiquity and diversity of Wolbachia in the insect orders Anoplura (sucking lice) and Mallophaga (chewing lice), by detecting single or multiple infections in each of 25 tested populations of lice, representing 19 species from 15 genera spanning eight taxonomic families. Phylogenetic analyses indicate a high diversity of Wolbachia in lice, as evidenced by the identification of 39 unique strains. Some of these strains are apparently unique to lice, whereas others are similar to strains that infect other insect taxa. Wolbachia are transmitted from infected females to their offspring via egg cytoplasm, such that similar species of lice are predicted to have similar strains of Wolbachia. This predicted pattern is not supported in the current study and may reflect multiple events of recent horizontal transmission between host species. At present, there is no known mechanism that would allow for this latter mode of transmission to and within species of lice.

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ABSTRACT. Nosema isolates from five lepidopteran forest defoliators, Nosema fumiferanae from spruce budworm, Choristoneura fumiferana; a Nosema sp. from jack pine budworm, Choristoneura pinus pinus and western spruce budworm, Choristoneura occidentalis (Nosema sp. CPP and Nosema sp. CO, respectively); Nosema thomsoni from large aspen tortrix, Choristoneura conflictana; and Nosema disstriae, from the forest tent caterpillar, Malacosoma disstria were compared based on their small subunit (SSU) ribosomal RNA (rRNA) gene sequences. Four of the species sequenced, N. fumiferanae, Nosema sp. CPP, Nosema sp. CO, and N. disstriae have a high SSU rDNA sequence identity (0.6%-1.5%) and are members of the ''true Nosema'' clade. They all showed the reverse arrangement of the (large subunit [LSU]-internal transcribed spacer [ITS]-SSU) of the rRNA gene. The fifth species, N. thomsoni has the usual (SSU-ITS-LSU) arrangement and is not a member of this clade showing only an 82% sequence similarity. We speculate, therefore, that a genetic reversal may have occurred in the common ancestor to the ''true Nosema'' clade. Although, the mechanism for rearrangement of the rRNA gene subunits is not known we provide a possible explanation for the localization. N. fumiferanae, Nosema sp. CPP, and Nosema sp. CO clustered together on the inferred phylogenetic tree. The high sequence similarities, the reverse arrangement in the rRNA gene subunits, and the phylogenetic clustering suggest that these three species are closely related but separate species.

Emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) is an invasive species from Asia that was discovered in North America Canada, in 2002. Herein, we describe studies to develop an autocontamination trapping system to disseminate Beauveria bassiana to control beetle populations. The standard trap for emerald ash borer in Canada is a light green prism trap covered in an insect adhesive and baited with (Z)-3-hexenol. We compared of green multifunnel traps, green intercept panel traps (both with and without fluon coating) and green prism traps for capturing emerald ash borer in a green ash plantation. The coated green multifunnel traps captured significantly more males and more females than any other trap design. We examined the efficacy of two native B. bassiana isolates, INRS-CFL and L49-1AA. In a field experiment the INRS-CFL isolate attached to multifunnel traps in autocontamination chambers retained its pathogenicity to emerald ash borer adults for up to 43 d of outdoor exposure. Conidia germination of the INRS-CFL isolate was >69% after outdoor exposure in the traps for up to 57 d. The L49-1AA isolate was not pathogenic in simulated trap exposures and the germination rate was extremely low (<5.3%). Mean (+/- SEM) conidia loads on ash borer adults after being autocontaminated in the laboratory using pouches that had been exposed in traps out of doors for 29 d were 579,200 (+/- 86,181) and 2,400 (+/- 681) for the INRS-CFL and the LA9-1AA isolates, respectively. We also examined the fungal dissemination process under field conditions using the L49-1AA isolate in a green ash plantation. Beetles were lured to baited green multifunnel traps with attached autocontamination chambers. Beetles acquired fungal conidia from cultures growing on pouches in the chambers and were recaptured on Pestick-coated traps. In total, 2,532 beetles were captured of which 165 (6.5%) had fungal growth that resembled B. bassiana. Of these 25 beetles were positive for the L49-1AA isolate.

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