Diversity of Biscogniauxia mediterranea within Single Stromata on Cork Oak

Charcoal canker, caused by the fungus Biscogniauxia mediterranea , is one of the most frequent diseases of cork oak in Portugal. The pathogen has been considered a secondary invader that attacks only stressed hosts; however, in recent years, an increasing number of young trees exhibiting the disease symptoms have been recorded. A collection of monoascosporic cultures isolated from single stromata of B. mediterranea in cork oak from different locations was analyzed by means of microsatellite—Primed Polymerase Chain Reaction—using three microsatellite primers, in order to detect the genetic variation of the population thus discussing its plasticity and ability to adapt to different conditions. The results showed a high level of genetic variability among isolates obtained from the same stroma, being impossible to distinguish isolates from individual stromata neither from different geographical location.