IDENTIFICATION OF PYTHIUM SYLVATICUM AND SPECIES-SPECIFIC PRIMERS
PYTHIUM SYLVATICUM鉴定及其专一性PCR引物

Pythium sylvaticum, a new record of Pythium in China, was isolated from damping-off seedlings of rice, cotton and soybean in Hangzhou region. Its a heterothallic species. This species is characterized by hyphal swellings frequent globose or limoniform, oogonia smooth, antheridia 1-3 per oogonia, diclinous, antheridial stalks branched, often bifurcate near the oogonium, oospores aplerotic. The study was conducted to sequence the rDNA internal transcribed spacer (ITS) region of P. sylvaticum, and to design species-specific primers for polymerase chain reaction (PCR), based on comparison of the sequence of the ITS region among 59 species of Pythium. Using PCR, the primer pair PSF1 PSR2, amplified isolates of P. sylvaticum from 14 isolates of 11 Pythium species, but not isolates of 10 other Pythium species.