Heart-rot and Decay Due to Polyporus palustris

Polyporus palustris Berk. and Curt. is encountered commonly in India as causing brown cuboidal decay of wood in service, besides causing heart-rot in living Cassia nodosa. It attacks hardwoods besides conifers on which it was hitherto known. The fungus described here has been recorded for the first time in India from sporophores. P. palustris has also been studied in culture. It is heterothallic and bipolar. Polyporus palustris Berk. and Curt. has so far been known as a decay fungus on conifers only, causing brown carbonizing rot in the heartwood (Overholts, 1953). Bagchee (1954) recorded the fungus in India from culture obtained from decayed spruce. The sporophore of P. palustris had not so far been recorded in India, though we have encountered the fungus as occurring commonly in India, both on hardwoods and conifers. It causes decay of sal (Shorea robusta) and chir (Pinus roxburghii ) poles treated with creosote in service. The fungus has been also encountered as a wound parasite, causing brown cuboidal heart-rot in Cassia nodosa, resulting in wind-throw of the tree (Pl. I, fig. 4).