Molecular studies confirmed the occurrence of Wisteria vein mosaic virus in Italy
Wisteria vein mosaic virus (Potyvirus - WVMV) is the causal agent of the Wisteria mosaic disease which can severely affect the following Wisteria species (Fabaceae): Wisteria brachybotrys, W. floribunda, W. sinensis, W. venusta. Although the disease was first observed in the USA in the 1940s, its viral etiology was elucidated only in the 1970s by studies conducted in the Netherlands. WVMV is thought to originate from Asia and has been reported in other continents, and in particular in several European countries (see below). WVMV causes mild mosaic, mottling, chlorotic spots, necrotic flecks, and distortion or twisting of the leaves, as well as reduced flowering, leading to a loss of the ornamental value of the plants. Severely affected plants are unmarketable. WVMV is primarily spread through vegetative propagation of infected plant material but can also be transmitted (non-persistently) by aphids (Aphis craccivora and Myzus persicae), as well as by grafting and mechanical inoculation to a range of indicators (e.g. Chenopodium giganteum (=C. amaranticolor), Nicotiana clevelandii).
In Italy, the presence of the virus was first detected by serology in Piemonte (Northern Italy) in the 1970s and recent molecular studies confirmed its occurrence on a W. sinensis plant showing severe symptoms in a garden in Puglia (Southern Italy). The authors consider that WVMV could present a serious threat to the nursery market, as wisterias are popular perennial plants that are widely planted for ornamental purposes in Europe. They consider that further efforts to monitor WVMV in wholesale and retail nurseries should be made to prevent the spread of this virus with infected plant material.
A tentative geographical distribution of WVMV has been included in the EPPO Global Database: https://gd.eppo.int/taxon/WVMV00/distribution
EPPO region: Czech Republic, Italy, Netherlands, Poland, United Kingdom (England).
Asia: China (Beijing, Jiangsu, Jiangxi, Zhejiang), Iran.
North America: USA (Maryland, Michigan, Mississippi, New York, Washington).
Oceania: Australia (New South Wales), New Zealand.
Sources
D’Attoma G, Minafra A, Saldarelli P, Morelli M (2023) Molecular evidence for the presence of Wisteria vein mosaic virus in Italy: Shedding light on genetic diversity and evolutionary dynamics of virus geographic populations. Agriculture 13, 1090. https://doi.org/10.3390/agriculture13051090