Quarantine species of Phytophtora genus causing diseases on tree and shrubs

Abstract

Phytophthora are fungi-like organisms belonging to the oomycetes. Species of this genus cause diseases that lead to economic losses and have ecological impacts in nurseries, forests, and natural ecosystems. The genus includes a lot of species that cause root and basal rots, wilting, leaf and stem blight, cankers, and stem dieback, leading to economic consequences worldwide. Some species are particularly harmful plant pathogens and are therefore included in quarantine lists of various countries. This article provides a brief overview of quarantine species of the genus Phytophthora associated with trees, shrubs, and ornamental plants. Species of this genus regulated in various countries are listed. It gives a description of the host plants and morphological characters of the pathogens that cause late blight of ornamental plants and shrubs – Phytophthora kernoviae Brasier, Beales & S.A. Kirk, Phytophthora ramorum Werres, De Cock & Man in't Veld, as well as Phytophthora alni Brasier & S.A. Kirk. The global distribution of these pathogens, as well as their phytosanitary status and harmfulness, is described. Illustrations of symptoms and key morphological diagnostic characters are provided.