In 2014, Physostegia chlorotic mottle virus (PhCMoV) was discoveredin Austria in Physostegia virginiana. Subsequent collaborative effortsestablished a link between the virus and severe fruit symptoms on importantcrops such as tomato, eggplant, and cucumber across nine Europeancountries. Thereafter, specific knowledge gaps, which are crucial to assessthe risks PhCMoV can pose for production and how to manage it,needed to be addressed. In this study, the transmission, prevalence, anddisease severity of PhCMoV were examined. This investigation led tothe identification of PhCMoV presence in a new country, Switzerland.Furthermore, our research indicates that the virus was already presentin Europe 30 years ago. Bioassays demonstrated PhCMoV can result inup to 100% tomato yield losses depending on the phenological stageof the plant at the time of infection. PhCMoV was found to naturallyinfect 12 new host plant species across eight families, extending its host range to 21 plant species across 15 plant families. The study alsoidentified a polyphagous leafhopper (genus Anaceratagallia) as a naturalvector of PhCMoV. Overall, PhCMoV was widespread in small-scalediversified vegetable farms in Belgium where tomato is grown in soil undertunnels, occurring in approximately one-third of such farms. However,outbreaks were sporadic and were associated at least once with thecultivation in tomato tunnels of perennial plants that can serve as a reservoirhost for the virus and its vector. To further explore this phenomenonand manage the virus, studying the ecology of the vector would bebeneficial.
