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Adult mites Balaustium murorum collected from a wild population died in laboratory storage containers and became mouldy. The fungus was identified as Purpureocillium lilacinum (predominate isolate) by 98% internal transcribed spacer (ITS) and beta-tubulin (Bt2a/Bt2b) BLAST match to authentic strains from soil. Larvae, deutonymphs, and adults could be artificially infected by topical application with a 107/ml spore inoculum, resulting in rapid dehydration and an increased mortality. This strain of P. lilacinum was more virulent to larvae than post-larval stages. Post-treatment, P. lilacinum was re-isolated internally with high frequency from cadavers. This P. lilacinum has a 25°C optimal growth temperature, 20-35°C thermal growth range, 0.997 aw optimal water activity (aw), and a minimum 0.96 aw to produce spores. Results indicate that infection with P. lilacinum can occur for population control, most likely during periods of moderate temperature and frequent rainfall. Because P. lilacinum is commercially available as a nematocide, application of P. lilacinum may reduce the effectiveness of Balaustium for plant pest control. This strain P. lilacinum UAMH 11932 is pathogenic to B. murorum and it has been deposited at the University of Alberta Microfungus Collection and Herbarium, Toronto, CAN. [ABSTRACT FROM AUTHOR]

Soil fungi were cultured from 24 wallows and proximal control sites in Maine and New Hampshire, USA during the autumn moose (Alces alces) breeding season of 2016 to investigate the presence of soil fungi pathogenic to winter tick larvae (Dermacentor albipictus). Twenty genera of fungi were isolated, and all are considered common in a forested ecosystem. The predominant genera isolated in wallows were pathogenic to winter tick larvae and included Aspergillus spp. (in particular A. flavus), Beauveria bassiana, Mortierella spp., Mucor spp., Paecilomyces spp., Penicillium spp., and Trichoderma spp. Wallow soils had specific characteristics and differed from proximal control sites by having: 1) lower fungal diversity, 2) a higher frequency of primary colonizers including Mortierella spp., Mucor spp., Penicillium spp., and Trichoderma spp., and 3) a more variable total amount of fungi indicative of changing (disturbed) soil conditions. We conclude that wallows are sites of soil disturbance that concentrate fungi known to be pathogenic to larval winter ticks. Fungi acquired by breeding moose using wallows might subsequently act as an on-host mechanism of tick control. [ABSTRACT FROM AUTHOR]