The adult Japanese beetle, Popillia japonica Newman, as a host and potential autodisseminator of the milky disease pathogen, Bacillus popilliae Dutky

Adult Japanese beetles, Popillia japonica, were evaluated for competency as hosts and potential autodisseminators of the milky disease pathogen. Bacillus popilliae. Adults were injected during a series of 20 replicates with either 1.0 x 10⁵, 5.0 x 10⁴, or 1.0 x 10⁴ spores and maintained for 16 days in a controlled environment. Forty-one percent of the females and 29% of the males were competent hosts. Eighty-four percent of the sporulation had occurred by days 10 and 11 postinjection. Competent beetles contained hemolymph which had an average of 1.6 x 10⁷ spores per µl 16 days postinjection. Beetles injected after mid-July were not competent hosts of the pathogen. A mark, release, and recapture study was conducted. No injected adults were recaptured out of the 1,200 released. Twenty of 4,000 control beetles released were recaptured within two days.