Molecular Identity of Species and Isolates of the Coniphora Cellar Fungi

Abstract

Summary Within the genus Coniophora, C. puteana and the less common species C. marmorata, C. arida and C. olivacea form a group of domestic brown-rot fungi (“cellar fungi”), which cause considerable decay in the woodwork of buildings. The fungi are difficult to distinguish by their fruit bodies. Traditional methods fail to identify species in a pure culture. Also with regard to decay of wood in use, the basidiomes rarely develop, and the surface mycelium on wood is sparse except for the fine dark strands. Thus, molecular techniques were applied to obtain a reliable method for differentiation and detection and to aquire a greater knowledge of the domestic Coniophora species. Isolates obtained from decayed wood and from culture collections and identified as domestic Coniophora species were used. The internal transcribed spacer (ITS) of the ribosomal DNA was amplified by polymerase chain reaction, sequenced and restricted by the endonuclease TaqI. The ITS sequences characteristic of C. puteana, C. arida, C. marmorata and C. olivacea were obtained and entered into the international databases. The sequence size ranges from 525 to 729 bp. The data supplement our collection of ITS sequences from domestic wood decay fungi built for the characterization of mycelium in culture. Most isolates belong to C. puteana and some to C. arida, C. marmorata and C. olivacea. Two other isolates belong to a further Coniophora species close to C. olivacea. Obviously, at least five Coniophora species occur within European buildings. Many of the isolates were not correctly identified. Consequently, the traditional characterization methods used, viz., growth rate, temperature influence and wood weight loss, were less suitable for the differentiation of Coniophora species as formerly anticipated.