Fungi associated with canker and dieback diseases of Quercus suber in Tunisia

Abstract: Decline events have recently been observed in several cork oak forests in northwestTunisia (Kroumirie). The affected trees show crown thinning, leaf yellowing, branch dieback,cankers, epicormic shoots and exudates on branches and trunk. Six fungi isolates: Biscogniauxiamediterranea, Botryosphaeria corticola, Cytospora sp., Discula quercina, Fusicoccum sp. andPleurophoma cava were constantly isolated from cankered and wilted branches of affected plants.Pathogenicity tests on 3-year-old cork oak seedlings confirmed the virulence of all species. Theresults obtained emphasize the need to develop further research into the real incidence anddistribution of these and other pathogens, which are potentially involved in the aetiology ofdecline in the Tunisian cork oak forest.