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This paper presents the process and the results of studies on fungitoxicity level of the chosen phenolic compounds occurring in wood that can be responsible for the natural resistance of this material to decay by fungi. All together 14 substances were exa¬mined: Eugenol, Vanillic acid, Isoeugenol, Cyclohexanone, Resorcinol, Syringaldehyde, 2,6-dimethoxyphenol (Syringol), Pyrogallol, 4-methoxybenzoic acid (Anisiic acid), 2- -furaldehyde, Furanone, 4-allyl-2,6-dimethoxyphenol, Tetramethyl-4-butanediamine and 3',5'-dimethoxyacetophenone and 6 different mixtures of these compounds imitating their natural coexistance in wood. For the tests the modified AG nutrient agar medium method based on using a series of media plates of various saturations of the tested substance was used. Trametes versicolor and Laetiporus sulphureus served as the test fungi. All together 20 variants of the experiment were pursued on 2400 plates. On this basis the fungitoxicity level of each substance was determined and they were evaluated in regards of their potential usefulness in the practical protection of trees and wood.
One of the methods limiting the damages done by Armillaria species is to decrease the number of dead wood stumps attacked by it, particularly it refers to deciduous tree stumps.The objective of the presented paper was an attempt to estimate the possibility to select some saprotrophic fungi species whose ability of decaying oak wood is higher and faster than that of Armillaria ostoyae (Romagn.) Herink and Armillaria gallica Marxm & Romagn, and which could be utilized in a biological protection method preventing Armillaria root-wood attack. All analyzed wood samples were colonized by tested mycelia. Among the fungi which could be utilized in a biological method of protection against root mould caused by Armillaria, the fungus Tramestes versicolor has shown to be the best suited for this purpose. Four different isolates were tested, which have confirmed their efficiency in decaying oak heartwood. Therefore, this fungus could be used for the elaboration of a biopreparation protecting effectively against Armillaria root rot.
The paper reports the laboratory research on the natural wood resistance against white pattern fungal wood decomposition. Wood samples of 25, both European and exotic, tree species were collected and used (tab. 1). All samples were dried and weighted, then put on the mycelium of four different white rot causing fungi species: Fomes fomentarius ((L.: Fr.) Kickx), Schizophyllum commune (Fr.: Fr.), Stereum hirsutum ((Willd.: Fr.) Gray) and Trametes versicolor ((L.: Fr.) Pilát). After 30, 60 and 90 days of exposition the samples were put out, cleaned, dried and weighted again. The weight loss indicated the range of wood decomposition and allowed to estimate its natural resistance against fungal wood decay. The results showed that in laboratory conditions the range of all fungi species trophic abilities were much wider than the one observed in nature. Examined fungi were able to destroy wood from trees they never occur on. The reasons of this could be both mechanical (the absence of bark – natural barrier for fungi) and chemical (the less of chemical substances occurring in wood of living trees that could be responsible for its natural resistance against fungi).
Armillaria root disease is one of the most important diseases causing losses in forestry, horticulture, pomiculture and agriculture. Fungi from Armillaria spp. infest roots and stem base in trees and shrubs, causing white wood rot. In Poland the most common species include Armillaria ostoyae (Romagn.) Herink, found both in coniferous and deciduous stands, and A. gallica Marxm. et Romagn. found in deciduous stands. Identification of antagonistic interactions between microorganisms in the soil medium enables to use their activity to protect plants against pathogens. Analyses were conducted on two Trametes versicolor isolates TR31 and TR55, collected from oak stumps, and 5 fungal species from the genus Armillaria: A. borealis Marxm. et Korhonen, A. cepistipes Velen., A. gallica, A. mellea (Vahl) P. Kumm. and A. ostoyae. Profiles of volatile compounds produced by T. versicolor isolates TR31 and TR55 determined in this study varied in their effect on growth of pathogens Armillaria borealis, A. cepistipes, A. gallica, A. mellea and A. ostoyae. TR31 more effectively than isolate TR55 inhibited growth of fungi from the genus Armillaria. Profiles of volatile compounds biosynthesised in the examined fungal cultures were assessed by headspace microextraction in a gas chromatograph coupled with a mass spectrometer. We detected 179 compounds in the analysed fungal cultures. They belonged to the following groups of chemical compounds: amines, alcohols, terpenes, aldehydes, ketones, hydrocarbons, heterocyclic compounds, esters and aromatic compounds (tab. 2). The most numerous group among the isolated volatile compounds comprised hydrocarbons, alcohols and esters at 32.4%, 16.2% and 14.5%, respectively. The highest concentrations reported in RU (i.e. the peak area of a given substances in relation to the peak area of the internal standard, i.e. tridecane) were recorded for aldehydes, alcohols and hydrocarbons. Among all the identified volatile compounds the highest concentration was observed for 2−methylbutanal. However, it was characteristic only of isolate TR31, which exhibited a greater capacity to inhibit growth of Armillaria spp. in comparison to isolate TR55 (fig.).
From research on the use of chiral ionic liquids with a natural origin substituenl for wood proteclion. Antifungal activities of chiral ionic liquids - menthoxymethylimidazolium derivates against brown-rot decay fungus (Coniophora puteana), white-rot decay fungus (Trametes versicolor) and blue-stain fungus (Sclerophoma pithyophila) were determined using screening agar-plate and agar-block methods. Results from antifungal tests revealed that 1-hexyl-3-[(1R,2S,5R)-(-)menthoxymethyl]imidazolium chloride exhibited the strongest antifungal activity against wood decay fungi (basidiomycetes) compared with the commercial didecyldimethylammonium chloride. Whereas compound with twelve carbons alkyl substituent has a weak antifungal activity. The infrared spectral analysis (FTIR ATR) confirmed that chiral imidazolium ionic liquids were built into the structure of the treated wood.
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