2018 ASHS Annual Conference

A survey of roses from several states within the US was conducted to identify eriophyoid mite species associated with Rosa spp. Various microscopy techniques including bright field, phase contrast, differential interference contrast light microscopy, table top scanning electron microscopy and low temperature scanning electron microscopy were used. Three species of eriophyid mites were discovered, P. fructiphilus, Eriophyes eremus, and Callyntrotus schlechtendali. Phyllocoptes fructiphilus is the mite vector for an Emaravirus, Rose rosette virus (RRV), the causal agent of rose rosette disease (RRD). This mite was found primarily under the petioles (stipules), inside the flower sepals appressed to the ovary/seeds and on open leaves during the growing season. This mite often hides amongst dense simple and bulbous, glandular hairs (trichomes) or under stipules/petioles. Eriophyes eremus has been found under the stipules and is now recorded for the first time on the American continent. Callyntrotus schlechtendali was found on the open leaf surface. The latter two species were not associated to obvious plant injury. In addition, predatory mites that were found associated with these eriophyid mites may be useful as biological control agents.