Parasitism of cacao by Fomes noxius in Papua-New Guinea
Tropical Agriculture 42(1): 63-67
F. noxius is the most important root-disease fungus of cacao in Papua-New Guinea, and evidence is presented that this pathogen manifests 2 distinct sets of symptoms. One is the characteristic brown root rot; the 2nd consists of a crust of mycelium on the lower trunk, which may extent to a height of 3 ft. and is seldom connected with mycelium on the roots. Infections of the 2nd kind have been recorded almost exclusively from the northern Gazelle Peninsula, where the light soils are derived from pumice. The reason for the unusual growth of mycelium up the trunk is unknown, but it may be associated with a soil factor.