Diversity and distribution of Diplodia spp. - causative agent of black canker on pome fruit trees - in Germany

Black canker, caused by fungi of the genus Diplodia, poses an increasing threat to pome fruit production in Germany. In order to determine the spread of the disease in Germany, 423 bark samples with suspicious symptoms from all federal states were examined in a non-representative monitoring. In 62% of the samples examined, fungi of the genus Diplodia were isolated, with the species D. bulgarica dominating the Diplodia species spectrum with 56.6%, followed by D. seriata with 28.3%. D. malorum (7.8%), D. mutila (4.9%), D. juglandis (1.6%) and D. intermedia (0.8%), on the other hand, took up only a small part of the Diplodia species spectrum, with the latter two species being first records on apple in Germany.