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Basidiosporogenesis by the white-rot basidiomycetes in vitr
1994 - IRG/WP 94-10081
Basidiospores of all forest-inhabiting basidiomycetes are a primary source of infection causing wood decay. However, most studies evaluating wood preservatives have used mycelia or basidiospores obtained from wild mushrooms. The objective of this study was to demonstrate in vitro methods that promote carpogenesis and basidiosporogenesis by the white-rot basidiomycetes, Schizophyllum commune and Trametes versicolor. After preincubation in the dark at 27°C for three to fifteen days, basidiospores were produced in four to sixteen weeks in basidiomes exposed to light at 12°C. Adequate light exposure, aeration, and low temperature treatment after preincubation are essential for fruiting body of these white-rotting basidiomycetes. Carpogenesis and basidiosporogenesis of Schizophyllum commune is controlled by nitrogen and carbon limitation. However, fruiting body formation in Trametes versicolor was induced by nitrogen limitation. Walset cellulose was found to be the best carboun source for carpogenesis and subsequent basidiosporogenesis. These results demonstrate the feasibility of using various potential inhibitors on basidiospore germination rather than relying on mycelial growth.
S C Croan


Basidiosporogenesis by brown-rot basidiomycetes in vitro
1995 - IRG/WP 95-10126
Basidiospores of wood-rotting basidiomycetes are a primary sourse of infection causing wood biodeterioration, especially in wood above ground. Most studies evaluating wood preservatives have used mycelia or basidiospores obtained from wild mushrooms. The objective of this study was to demonstrate in vitro methods that promote carpogenesis and basidiosporogenesis by the brown-rot fungi Antrodia carbonisa, Neolentinus lepideus, and Postia placenta. After preincubation in the dark at 27°C for 3 to 11 days, basidiospores were easily prodused in 1 to 4 months by basidiomata exposed to light at 12°C. Adequate light exposure, aeration, and low temperature treatment after preincubation are essential for fruiting body formation of these brown-rot basidiomycetes. The morphology of the basidiomata differed according to the basidiomycetes and the medium used. These results demonstrate that an enormous quantity of basidiosporee can be easily and continuously prodused in 2 to 4 months in vitro.
S C Croan


Bioconversion of wood wastes into gourmet and medicinal mushrooms
1999 - IRG/WP 99-50129
Increased wood wastes, including thinned material from stagnated and overstocked small-diameter forests, are a menace to forest health, to the sustainability of ecosystems, and to community economic viability. The objective of this study is to recycle wood wastes into value-added products, such as gourmet and medicinal mushrooms, by using the white-rot basidiomycetes, Pleurotus ostreatus, P. populinus, P. pulmonarius, and other Pleurotus species. When supplemented with low concentrations of dextrose, these basidiomycetes exhibit an excellent ability to colonize and stimulate fruiting body production on wood wastes. Inoculated wood wastes in air-permeable bags are incubated at 24°C in the dark for 3 to 5 weeks. When exposed to light cycle (10-h day), humidity, and air, they fruit within 4 to 8 weeks. Lyophilization of cultures stimulates filamentous mycelial growth and fruiting is then initiated within 3 to 7 days.
S C Croan


The effect of storage and subculturing on in vitro fruit body formation and spore production in Gloeophyllum sepiarium and Oligoporus placentus
2001 - IRG/WP 01-20232
Spores are widely assumed to be the main mode of infection of wood in conditions conducive to decay above ground. In order to supply spores on demand as an experimental material, fruiting body and basidiospore production in vitro by Gloeophyllum sepiarium and Oligoporus placentus have been examined. The optimum medium, time to spore production, and duration of fruiting as well as fruiting body shape varied among strains of both species. Even when the same strain was used as the inoculum source, there were differences in duration of fruiting and time to spore production in different experimental sets. This suggests that the method of mycelium storage and repeated subculturing could affect fungal capacity for fruiting and basidiospore production. Among the tested methods of mycelium storage, mycelia stored on wood blocks showed the most stable response in both fruiting and spore production.
S Choi, J N R Ruddick, P I Morris


Conditions for basidiospore production in the brown rot fungus Gloeophyllum separium in axenic culture
1984 - IRG/WP 1232
Attempts to control and optimize the production of hymenial structures and basidiospore production in Gloeophyllum sepiarium in axenic culture resulted in the proposal of the following conditions as being suitable. The dikaryotic mycelia originally isolated from basidiocarps could consistently be induced to produce hymenial structures and pure basidiospore collects if illuminated by near ultraviolet light with emission maximum at 355 nm ("black light") at a temperature of 15°C on a chemically defined medium, where the concentration of the carbon and the nitrogen sources were shown to be of critical significance. The necessary conditions for basidiospore production in lignicolous fungi in general are is briefly discussed.
J Bjurman


Influence of abiotic factors on the production of Basidiocarps by lignocellulolitic Hymenomycetes from native forest and plantations of Pinus elliottii Engelm in the Fontes do Ipiranga State Park, São Paulo, Brazil
1991 - IRG/WP 1469
A report on the influence of abiotic factors on the production of basidiocarps by lignocellulotic Hymenomycetes of native forest and Pinus elliottii. It was concluded that the climatic conditions (temperature, humidity, microhabitat) and the decay stage of the logs affected the production of basidiocarps by Hymenomycetes.
M Aparecida de Jesus


Distribution of cellulases in the body of Coptotermes formosanus and the probability that the termite uses glucose as an energy and carbon sources
1997 - IRG/WP 97-10202
We assayed extracts of the digestive system and of the whole body of Coptotermes formosanus to determine where the various cellulases, glucose, and related substances were concentrated and to detect pyruvate dehydrogenase activity in the hindgut-removed body in order to verify its full cellulolytic system. About 20%, 18% and 36% of the total exo-1,4-ß-glucanase activity of C. formosanus were detected in the salivary glands, midgut, and hindgut, respectively. About a third of the total endo-1,4-ß-glucanase activity in the termite was detected in the salivary glands (34.5%) whereas the activities in the midgut and hindgut were 21.1% and 18.2%, respectively. About 75% of the total ß-D-glucosidase activity in the termite was detected in the midgut. Thus all the necessary cellulases for hydrolysis of natural cellulose to glucose were present in the region ranging from the salivary glands to the midgut in significant amounts. Most of the glucose and trehalose detected in the termite existed in the gutted-body. Most of the glucose detected in the gut existed in the midgut. Pyruvic acid was directly converted to acetyl-CoA in the presence of NAD+ by a crude extract of the gutted-body. These results suggest that natural cellulose ingested by the termite is hydrolyzed to oligosaccharides in the region of the foregut and midgut as well as in the hindgut, that oligosaccharides are hydrolyzed to glucose predominantly in the midgut, and that the resultant glucose is absorbed through the midgut wall into the tissues to be used as important energy and carbon sources.
S Itakura, H Tanaka, A Enoki


Towards harmonisation of regional approaches for an International Standard for the approval of wood preservatives
1997 - IRG/WP 97-20122
Recent proposals from the European Standards body (CEN) for an ISO Standard on wood preservatives has initiated debate on whether there is any prospect of an acceptable common approach among ISO member countries, to a harmonised framework of hazard classes, with agreed supporting biological tests, leading to a unified rationale for demonstrating compliance with minimum performance standards for specific preservatives in specific end-uses. This paper discusses a potential framework for developing an International Standard prescribing hazard classes and the biological test methods capable of supporting a common approach to the approval or standardisation of a wood preservative system. An approach is proposed which incorporates elements of existing standards or protocols used in Europe, Japan, Australasia, South Africa and North America based on the framework of European Standard EN599 but adopting regional variants with incorporation of field testing for the suggested Hazard Classes 2, 3, 4a, 4b and 5. The proposals are intended to initiate development of a consensus process rather than to suggest a solution in itself. However, it is hoped that the framework provided will allow the discussion process to advance more effectively and harmoniously.
A F Preston, A F Bravery


Is termite body size correlated with colony vigor?
1995 - IRG/WP 95-10130
Folk wisdom among termite researchers holds that the average body size (mass) of workers in a subterranean termite colony (Rhinotermitidae) is associated with the age and/or vigor of the colony. In particular, extremely large individuals are frequently thought to indicate a very old, or senescent, termite colony. However, there are very little data to support this assumption. It is also difficult to understand why subterranean termite colonies of advanced age, with a continuing food supply and supplementary reproductives presumably active in egg production, should be prone to senescence. We present data from 16 years of observations on a Coptotermes formosanus Shiraki field colony demonstrating a negative proportional relationship between average individual worker mass and estimated size of the colony foraging population. These results do not explain the phenomenon of senescence, but do suggest that decline in colony population size may be predicted from a measured increase in the average individual mass of workers sampled over a given period of time.
J K Grace, R T Yamamoto, M Tamashiro


Evaluation of white-rot fungal growth on Southern Yellow pine wood chips pretreated with blue-stain fungi
2000 - IRG/WP 00-10349
White-rotting basidiomycetes do not colonize on southern yellow pine. This study seeks to reduce the resinous extractive content of southern yellow pine by treating it with blue stain fungi. The mycelial growth of wood-inhabiting ligninolytic white-rot fungi can be achieved on pretreated southern yellow pine wood. Aureobasidium, Ceratocystis, and Ophiostoma spp. removed 70% to 100% of the extractives from the southern yellow pine wood within a period of 3 to 6 days. Griofora fondosa, Hericium erinaceus, and Pleurotus ostreatus colonized readily after the treatment. As a result, ligninolytic white-rot fungi can be easily colonized on southern yellow pines pretreated with blue stain fungi.
S C Croan


A physiological role of the glyoxylate and TCA cycles in fruitbody formation of the coppertolerant brown-rot fungus Fomitopsis palustris
2002 - IRG/WP 02-10430
Changes in activity of the representative enzymes involved in biosynthesis of oxalic acid (oxalate) and carbon metabolism of glucose were investigated in relation to the fruit body formation of the copper-tolerant brown-rot fungus Fomitopsis palustris. Changes in specific activities of the two glyoxylate (GLOX) cycle key enzymes (isocitrate lyase (ICL) and malate synthase (MS)), the two oxalate-forming enzymes (oxaloacetase (OXA) and glyoxylate dehydrogenase (GLOXDH)), and a tricarboxylic acid (TCA) cycle enzyme (isocitrate dehydrogenase (IDH)), were measured during the fungal growth. The enzymes for GLOX cycle and oxalate synthesis in mycelia showed greater activities at the stage of mycelial growth than at the fruiting stage. At the fruiting stage, the IDH/ICL activity ratios was reversed, rising from 0.3 to 2.0. Thus, the results obtained indicate that IDH of the TCA cycle plays a more important role than ICL of GLOX cycle for the fruit body formation of F. palustris, whereas ICL is more important than IDH for the oxalate biosynthesis at the earlier satge of the cultivation.
Jeong-Jun Yoon, T Hattori, M Shimada


Succession after Fire of Fungal Fruiting Bodies in Mediterranean Pinus pinaster Stands in Spain
2012 - IRG/WP 12-10789
In this study we present the results of a 4-year survey aimed at describing the succession of fungal communities following fire in a Mediterranean ecosystem in Northwest Spain, dominated by Pinus pinaster Ait. After a large wildfire in 2002, six 2 x 50 m study plots were established in burned and unburned areas corresponding to early and late succession stages. During the autumn seasons from 2003 to 2006, fruiting bodies were collected and identified. We also collected information about dry and fresh weight, the saprotrophic or mycorrhizal status and the edibility of every species. During the four-years sampling, a total of 115 fungal taxa were collected (85 in the late stage and 60 in the early stage) from which only 30 appeared along the whole succession. Mycorrhizal population not only increased the number of species from early to late stage but also shifted in composition. After fire, pyrophytic species such as Pholiota carbonaria, Peziza violacea, Rhizopogon luteolus and Rhizopogon sp. appeared. The effect of fire on fungal fruiting body’s production was opposite depending on the saprotrophic or mycorrhizal status of the species: mycorrhizal decreased 6-fold, while saprotrophic increased 4-fold. Production of edible species was negatively affected by fire, decreasing significantly the potential of rural populations to harvest marketable mushrooms. The provided results can be useful to forest managers for optimization of management and harvest of these increasingly appreciated non-wood resources. Management may also prevent or alleviate stand-replacing wildfire in these Mediterranean forests.
P Vásquez Gassibe, M Hernández-Rodriguez, R Fraile Fabero, J A Oria-De-Rueda, P Martín-Pinto