Phellinus noxius . [Descriptions of Fungi and Bacteria

Abstract

Abstract A description is provided for Phellinus noxius . Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On trees belonging to over 50 tropical genera; especially Hevea, Elaeis and Thea . DISEASE: Brown root rot particularly of rubber, oil palm and tea. The roots of diseased trees are characteristically encrusted with a mass of sand, earth and stones intermingled with and held together by the brown mycelium, which eventually turns black. A crust of mycelium may form on the trunk under certain conditions in New Guinea (44, 1483). The attacked wood is discoloured reddish-brown or brown mottled with white patches. In advanced stages of decay, the wood becomes light dry and friable and honey-combed, and a brown network of lines appears on the surface of the wood under the bark. GEOGRAPHICAL DISTRIBUTION: Africa (Cameroon, Congo, French Equatorial Africa, Ghana, Ivory Coast, Kenya, Nigeria, Tanzania); Asia (Ceylon, Formosa, India, Indonesia, Malaysia); Australasia & Oceania (Australia, Fiji, Papua & New Guinea, New Hebrides, Samoa); Central America & Caribbean (Costa Rica, Cuba, Puerto Rico). (CMI Map 104, ed. 2, 1964) and Fidalgo (1968). TRANSMISSION: Infection of freshly exposed tree stumps is by air-borne spores. Carpophores may sporulate up to 6 weeks (42: 145). Healthy roots in contact with infected roots or dead wood are invaded, those of 6-yr-old rubber trees appearing more susceptible than 20-yr-old trees (33: 256). The pathogen may survive up to 4 yrs in buried roots 3 inches diam., depending on soil conditions (40: 427).