Phytophthora pini Leonian resurrected to distinct species status.

Phytophthora pini was named by Leonian in 1925, but this species was largely ignored until 1956 and then merged with P. citricola by Waterhouse in 1963. This study compared the ex-type and ex-authentic cultures of these two species with isolates of P. plurivora and the P. citricola subgroups Cil I and III reported previously. Examination of these isolates revealed that the ex-type culture of P. pini is identical to P. citricola I. Phytophthora pini Leonian therefore is resurrected to distinct species status and redescribed here with a Latin description, replacing P. citricola I. Molecular, physiological and morphological descriptions of this species are presented. The molecular description includes DNA sequences of five nuclear and mitochondrial regions as well as PCR-SSCP fingerprints. The relationship among the above species and other species recently segregated from the P. citricola complex also is discussed.