Molecular and serological detection of Parietaria mottle virus in Phytolacca americana, a new host of the virus

Parietaria mottle virus (PMoV) is an emerging virus in Mediterranean countries, responsible for severe disease in tomato and pepper crops in the field and protected cultivation. The principal wild reservoir of PMoV is Parietaria officinalis, and only few additional wild plants have been described as natural reservoirs of the virus. During field survey in southern Italy, several plants of Phytolacca americana showing virus-like symptoms were collected. Serological and molecular assays showed that these plants were infected by PMoV. Sequence comparison of the movement protein gene of the PMoV isolate from P. americana showed the greatest similarity to the corresponding sequence from tomato plants growing nearby. These results indicate that P. ameriacana is a new natural host of PMoV, and further investigation is warranted to establish the potential of this host as reservoir of the virus in the field.