Survey of Basidiomycets and Insect Infested Roadside Trees

Abstract

Some biotic and abiotic factors causal to the deterioration of roadside trees were surveyed in Fukuoka City on 23 species planted along 22 main streets. Various fruit bodies of basidiornycete, imperfect fungi and bacterial canker disease as well as insect pests were detected. Forty - six fungi strains were obtained in this survey. Aphyllophorales basidiomycete was the most abundant fungi found in surveyed raodside trees. Fruit bodies of 7 edible mushroom species were identified on the scaffold limbs, trunks and root collars of roadside trees. Population of all wood­ inhabiting basidiomycetes from healthy and diseased trees were significantly different. Robinia pseudoacacia declined severely with mycerial development and fruit body formation of white rot fungi, Fomitella fraxinea on root collars. It is conceivable that low soil pH might be a major factor. Fifty - one species of tree insects were identified in this survey, major pests being two species of termites (Isoptera), Reticulitermes speraius kyushuensis and Copiotermes formosanus which significantly attacked ten tree species. Cerarnbycid beetles, Anoplophora malasiaca and Eupromus ruber severely damaged Platanus orienialis and Machilus thunbergii, respectively. Root damage status corresponded significantly to the degree of upper tree decline. Results clearly show differences between evergreen broad-leaved trees and deciduous broad -leaved trees in tolerance to wood-inhabiting basidiomycetes and tree-parasitic insects. Overall, this preliminary survey documents some biotic and abiotic factors may contribute to roadside tree decline in Fukuoka City.