Survival ofPhellinus noxiusin Soil and in the Roots of Dead Host Plants

Abstract

The survival of Phellinus noxius arthroconidia, basidiospores, and mycelia and of P. noxius-colonized wood was measured in soils with different soil matrix potentials. Survival of arthroconidia declined more slowly in soils with -0.50 and -0.42 MPa of soil matrix potential compared with soils with -0.15 and -0.025 MPa. However, arthroconidia were rarely recovered from the treatments after 3 months. Basidiospores were not recovered after 3, 3.5, 4, and 4.5 months in the -0.025, -0.15, -0.42, and -0.50 MPa soil matrix potential treatments, respectively. Mycelia that were buried in the soil with -0.025 MPa were not recovered after 4 weeks, whereas mycelia in soils with -0.50, -0.42, and -0.15 MPa were not recovered after 10 weeks. P. noxius was not recovered from pieces of artificially infested wood subjected to 1 month of flooding. However, in treatments with lower soil moisture, P. noxius survival ranged from 80% to more than 90% over 2 years. Colonies of P. noxius were not recovered from the rhizosphere of soils around the infested roots of three host species, Calophyllum inophyllum, Casuarina equisetifolia, and Cinnamomum camphora. However, P. noxius was recovered from naturally infected roots of these hosts 1 to 10 years after they were killed. These results indicated that woody debris in soils harboring P. noxius played an important role in the long-term survival of the fungus. Flooding infested fields may help control P. noxius in the field.