A long-term study of Phytophthora species in Germany. 1. Phytophthora species which could be definitely identified

Taxonomical investigations with Phytophthora isolates in Germany of the las t 14 years are presented in two different publications. The Phytophthora is olates originated from heavily damaged horticultural crops, including nurse ries, from trees in forests and in urban horticulture and from soil samples . In part 1, those isolates which could be definitively identified as known P hytophthora species are summarized. Furthermore, a detailed description of the methods used for isolation and for the taxonomical procedure is given. The dominant Phytophthora species which could be isolated were P. nicotiana e, P. cactorum, P. citricola, P. cryptogea and P. drechsleri. Furthermore n ew Phytophthora/host interactions could be detected. With P. cinnamomi, the mating type A1 was first detected in Germany in 1993.