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Mycoparasitism by some white rot fungi on blue stain fungi in culture
1986 - IRG/WP 1304
When studying biological control of blue stain an interesting phenomenon of parasitism by some white rot fungi on blue stain fungi has been encountered. The majority of the 22 tested white rot fungi act parasitically upon blue stain fungi. The most interesting species among them is Bjerkandera adusta (Willd. ex Fr.) Karst., causing almost complete or complete decoloration of the hyphae of the blue stain fungi in culture on agar substrate. Obviously, complex enzyme reactions are involved; the main role probably performed by peroxidases. Bjerkandera adusta (Willd. ex Fr.) Karst., acted similarly upon blue stained wood, which was rapidly bleached.
R Benko, B Henningsson


Controlling the sapstain fungus Ceratocystis coerulescens by metabolites obtained from Bjerkandera adusta and Talaromyces flavus
1993 - IRG/WP 93-10024
Sapstain causes severe damage to wood and wood products, posing a major economic problem for the wood industry. The purpose of this study was to determine if metabolites from Bjerkandera adusta and Talaromyces flavus would (1) decolorize stain in wood caused by Ceratocystis coerulescens and (2) prevent sapstain by Ceratocystis coerulescens. We studied the interaction of the sapstain fungus Ceratocystis coerulescens against the test fungi Bjerkandera adusta and Talaromyces flavus in dual cultures on agar medium. The metabolites obtained from test fungi were examined on pine veener disks stained by Ceratocystis coerulescens. Our results indicate that the test fungi were antagonistic to the sapstain fungus Ceratocystis coerulescens. The combination of metabolites from the antagonists decolorize the sapstained pine veener disks and killed the existing growth of Ceratocystis coerulescens.
S C Croan, T L Highley


Degradation of resin constituents in various wood species by the white rot fungus Bjerkandera sp. strain BOS55
1999 - IRG/WP 99-10301
In previous studies, the white-rot fungus Bjerkandera sp. strain BOS55 was shown to cause extensive degradation of lipophilic extractives (resin) in Scots pine wood. Further research was carried out in order to investigate the ability of Bjerkandera sp. for reducing resinous constituents in various softwood (Douglas fir, larch and spruce) and hardwood species (birch, beech and poplar). The greatest resin reduction occurred in beech (79% in two weeks). High levels of resin elimination were also observed in softwood species like spruce (36%) or Scots pine (35%), as well as in hardwood species like poplar (32%) or birch (24%). In contrast, Bjerkandera sp. only caused a negligible loss of resin components in Douglas fir wood chips. HPLC analysis of acetone extracts from control and fungal-treated samples showed a rapid elimination of triglycerides, diglycerides, free fatty acids and sterols. Toxic constituents in softwood species like resin acids were partially removed in Scots pine, spruce and larch (29-34% in two weeks).
J Dorado, T A Van Beek, F W Claassen, R Sierra-Alvarez