Plant species (72) representing 22 genera within 8 tribes of the Gramineae were tested for susceptibility to systemic colonization after conidial inoculation with 2 isolates of P. philippinensis from the Philippines. All susceptible species were members of the tribe Andropogoneae (genera Andropogon [1 sp], Bothriochloa [10 spp.], Eulalia [1 sp.], Saccharum [1 sp.], Schizachyrium [3 spp.], and Sorghum [3 spp.]) or the tribe Maydeae (genera Tripsacum [1 sp] and Zea [3 spp.]). Not all accessions susceptible to 1 isolate of the pathogen showed systemic symptoms when inoculated with the 2nd isolate; in some instances, only a few plants of an accession developed systemic symptoms. The results were similar to a previous host range study with P. sacchari from Taiwan. Close phylogenetic relationship between P. philippinensis and P. sacchari is indicated.