Host Plant Species of the Cicada Metcalfa Pruinosa in Romania

Metcalfa pruinosa (Say) is an invasive species native to North America, accidentally introduced to Europe, more specifically to Italy in 1979. In Romania it was observed for the first time in Constanta and a year later it was found in Timisoara, in the Western part of Romania too. In its place of origin the cicada consumes over 120 species of plants meanwhile in Europe, over 300, which indicates an emphasized polifagism. The aim of our studies was to identify new host plants and habitats in Romania. Observations took place in 13 counties of Romania in order to identity new host plants and habitats. Observations were performed in counties: Timis, Arad, Bihor, Hunedoara, Sibiu, Mures, Alba, Cluj, Mehedinti, Dolj, Salaj, Ilfov and Arges. The host plants were identified and the degree of attack was evaluated. The degree of attack was correlated with the number of host plants from an observation point. The number of attacked species was the highest in Timis county, where the degree of attack was also the highest, with an average value of 4.0. The most attacked plant species belonged to genera: Prunus, Buxus, Rosa, Hibiscus, Acer and Ligustrum. There is a positive correlation between the number of attacked plant species and the degree of attack. It has been found that where the diversity of plant species is high, Metcalfa pruinosa also has a larger population, and it is more likely to find the optimum plants for nutrition.