Ovavesicula popilliae, a widespread and potentially important protozoan pathogen of Japanese beetle in Connecticut, was only found at one location of 40 in Michigan. We have successfully introduced it to 5 study sites in Michigan. In research plots at one location, 80% of the larvae sampled in October, 2000 were infected. Within the plot area, the larval density is 50% lower than in surrounding areas. We are collecting data on Japanese beetle populations at 5 introduction sites and comparing with the same at 5 control sites to determine what impact Ovavesicula and other introduced pathogens and parasitoids have on Japanese beetle populations. We are also investigating the importance of a gregarine found at 50/50 locations in Connecticut, and 24/40 locations in Michigan. In the first greenhouse experiment, infection with the gregarine reduced grub weight and caused 20% mortality within 6 weeks. Tiphia vernalis and Istocheta aldrichi were also absent in Michigan and have been introduced, but not yet recovered at the time of this writing.
Species 1: Coleoptera Scarabaeidae Popillia japonica (Japanese beetle)
Keywords: Ovavesicula Gregarine
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA