Fichten-Mykorrhizen auf Standorten der Schwäbischen Alb und ihre Beziehung zum Befall durch Fomes annosus

Spruce mycorrhizac and heart rot incidence caused by Fomes annosus in southwestern Germany. Naturally occurring spruce mycorrhizac on calcareous soils of southwestern Germany were investigated and classified. These soils are characterized by a relatively high incidence of heart rot caused by Fomes annosus. On comparable sites stand history (former woodlands versus former sheep pastures), though influencing heart rot incidence, had no effect on the overall distribution of mycorrhizal types. The occurrence of rare types, however, varied between sites with different stand history. For all mycorrhizal types found, isolation of the fungal symbiont was attempted. Where isolation was successful, the isolates showed no antibiotic activity against Fomes annosus.     

Infektion und abbau der Wurzelrinde von Fichte durch Fomes annaus1

Infection and Deterioration of Spruce Root Bark by Fomes Annosus . The paper describes the mode of infection and consequent deterioration of spruce root bark by the root rot fungus, Fomes annosus using light and electron microscope observations. Spread of fungal hyphae occurs through bore holes produced by enzymatic activity. Although a definte loss of wall substance occurs, the bark tissues primarily represent merely a pathway for the fungus before it colonieses the xylem.     

Eine Methode zur Prüfung der Anfälligkeit und Ausbreitungsresistenz der Fichte (Picea abies Karst.) gegenüber dem Wurzelschwamm Fomes annosus (Fr.) Cooke1

A method for examining Norway spruce (Picea abies Karst.) for susceptibility and resistance to the spread of Fomes annosus (Fr.) Cooke . An easily applied method is described for determining the results of infections and the reactions of young Norway spruce to Fomes annosus. By the use of genetically homogeneous material, e. g. clonal plants, the importance of environmental factors such as nutrient supply and also the varying virulence of different fungal strains can be studied.     

Antagonists of Fomes annosus in the rhizosphere of grey alder (Alnus incana) and Norway spruce (Picea abies)

A comparison was made of the fungistatic effects of the root microflora of grey alder and Norway spruce with Fomes annosus as test fungus. The significantly higher frequency of actinomycetes in the alder rhizosphere probably constituted the main difference in this respect. The importance of fungi seemed to be about equal in the rhizosphere of the two tree species. Methods for studies of antagonism are tested and discussed.     

Zum Vorkommen von Fomes annosus (Fr.) Karst. im Boden von Fichtenbeständen (Picea abies Karst.)1

Occurrence of Fomes annosus in the soil of spruce stands (Picea abies Karst) . In stands of spruce Fomes annosus was found to occur in a viable state in the litter and soil to a depth of 25 cm. Successful isolations were obtained from 153 samples out of a total of 216. In ca. 40% of the 153 samples Fomes annosus could be isolated from 9 mg of soil; in the remaining samples it was found either in 90 mg, 230 mg or in 900 mg. The results raise the possibility of direct infection of the roots of spruce by Fomes annosus from the soil.     

Méthode ?estimation de la hauteur de pourriture dans le tronc des épicéas sur pieds attaqués par le Fomes annosus (Fr.) Cooke

Estimating the height of decay in standing Norway spruce attacked by Fomes annosus (Fr.) Cooke. A method is given for estimating the height of decay due to Fomes annosus in standing Norway spruce. A good correlation is provided by the height of the decay and, at the 1,30m level, the diameter and stage of the decay. The data were obtained using Pressler borings.     

Beziehungen zwischen der Ausbreitung künstlicher Fomes annosus-Infektionen in den Stämmchen zweier Fichtenklone und einigen holzchemischen Eigenschaften

The spread of Fomes annosus from artificial infections of stems, in relation to the chemical characteristics of timber of two spruce clones . Differences in the spread of Fomes annosus in two spruce clones (Picea abies Karst.), which were found by DIMITRI, may be attributed to differences in the properties of the wood from the two clones, detected in laboratory tests. Wood meal from the more resistant clone R inhibited Fomes annosus in bioassays more than wood meal from the more susceptible clone A. Wood from clne A-trees showed a higher nitrogen content than wood from clone R-trees.     

Fomes annosus (Fr.) Cke. und andere Stammfäulepilze in einem Douglasienbestand,Pseudotsuga menziesii (Mirb.) Franco1

Fomes annosus (Fr.) Cke. and other decay fungi in a Douglas fir stand, Pseudotsuga menziesii (Mirb.) Franco. 40% of the trees in a 40 years old Pseudotsuga menziesii stand showed butt rot. 85 trees were analysed for decay fungi. Fomes annosus, the most frequent fungus, also invaded the sap wood. Factors of the soil favourable to the rot and the possibility of transmission of the most frequent decay fungus, Fomes annosus, from (a) neighbouring spruce stands, (b) from the roots of Scots pine from the previous crop arc discussed. Caniophora puteana was isolated from about 10% of the butt rots. The importance of Calocera viscosa which grew out of the central decay of twelve trees as a decay fungus is still under investigation.     

Wundfäule in Fichtenwaldungen mit alten Schälschäden

Wound decays in spruce stands following bark stripping . 2083 trees in 91 sample plots on four trial areas (24 ha) were examined for bark stripping and decay. Only 25% of trees showed no injury. Of the injured trees, 73% showed some degree of decay, 10% discoloration. and 17% neither decay nor discoloration. Of the wood destroying fungi isolated Fomes annosus was dominant and appeared to be the most important and widespread of the wound inhabiting fungi in the test area. Besides the Basidiomycetes a considerable number of other fungi was isolated. The most frequent was Cylindrocarpon cylindroides var. tenue.     

Stamm- und Wurzelfäulen in Douglasien,Pseudotsuga menziesii (Mirb.) Franco1

Stem and root rot of Douglas fir, Pseudotsuga menziesii (Mirb.) Franco. In 20 year old Douglas fir most of the butt rot was caused by Fomes annosus. Stem decay was central as well as eccentric reaching the sap wood in either case. The side roots of 20 year old Douglas fir were compared with those of a 40 year old stand with butt rot. In individual trees with decay there were less roots with Fomes annosus decay in the younger stand. Calocera viscosa was more abundant in the older stand. Soil conditions which might have favoured root rot in the young stand are discussed.     

Fomes annosus sporocarps - their abundance on decayed logs left in the forest

On logs of Norway spruce, discarded and left lying after thinning because of severe decay by Fomes annosus, numerous sporocarps of F. annosus develop after one to two years. The surface area, position, number, and time of appearance of the fruiting bodies varied between two test areas. Removal of rotted logs is recommended as a prophylactic method of Fomes control in Picea abies stands.     

Fomannoxin,a phytotoxic metabolite of Fomes annosus: in vitro production,host toxicity and isolation from naturally infected Sitka spruce heartwood

The effect of different culture conditions on growth and production of fomannoxin and the sesquiterpene phytotoxin fomannosin by a single isolate of Fomes annosus was studied. Whereas fomannoxin was produced by actively growing hyphae, fomannosin production was associated with the declinning growth phase of the fungus. The presence of fomannoxin in chloroform extracts from the stained stein heartwood zone of Fomes annosus diseased Sitka spruce trees was established. Fomannosin however was not detected. Toxicity of fomannoxin to germinating seeds and young seedlings of Sitka spruce was demonstrated.     

Über die Infektion von Fichtenwurzeln (Picea abies Karst.) durch Forties annosus (Fr.) Cke.

Infection of roots of spruce (Picea abies Karst.) by Fomes annosus present in the soil. 108 roots of spruce were severed at approximately 50 cm from the base of the tree. The resulting wounds were invaded by Fomes annosus originating as mycelium or basidiospores in the soil. Infection rate on limestone soils was 41 %, on other soils 10 %. Odontia bicolor also grew into spruce roots from the soil.     

Genetic variation in Picea abies (L.) Karst. and Fomes annosus (Fr.) Cke. shown by growth of the fungus on wood dust

Growth of Fomes annosus is studied by a test based on growth of previously starved hyphae on sawdust of heartwood of Picea abies as the only nutrition. Our observations show that the method can be used to distinguish beween different spruce individuals or clones, between different Fomes annosus strains and between different growing sites of the trees.     

Fomes annosus Butt-Rot of Sitka Spruce IV. Observations on the Distribution of Cryptosporiopsis abietina (Petrak) in the Stems of Rotted Trees

Cryptosporiopsis abietina was isolated from the heartwood of12 out of 18 Sitka spruce suffering from butt rot caused byFomes annosus, but from none of eight healthy trees from thesame plantations. C. abietina was present in a distinct zoneabove the tissue colonised by F. annosus. It was present inboth sound wood, and in wood with stain or incipient decay. C. abietina inhibited the growth of F. annosus on malt agar,and to a lesser extent in autoclaved Sitka spruce heartwood.The possible influence of this potentially antagonistic funguson infection by F. annosus is briefly discussed.     

Hallimasch (Armillaria mellea Vahl ex Fr.) Kumm.) als Kernfäule-Erreger an Fichte (Picea abies Karst.)

Zusammenfassung In Fichtenbest?nden (Picea abies) tritt der Hallimasch (Armillaria mellea) h?ufig als Erreger einer Kernf?ule im Stamm lebender B?ume auf. Die F?ule geht von der Basis des Wurzelstockes aus. Im Vergleich zu einer durchFomes annosus verursachten F?ule breitet sich die Hallimaschf?ule in radialer Richtung etwas langsamer, in axialer Richtung aber erheblich langsamer aus, so da? sie meist nur eine sehr geringe H?he erreicht. Die Bedingungen für das Auftreten der Hallimaschf?ule sind noch nicht bekannt.

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Summary In spruce forestsArmillaria mellea frequently is the cause of a butt rot in living stems. The decay starts in the center of the stem base. Compared toFomes annosus theArmillaria rot does grow in the radial direction slightly more slowly, but in the axial direction much more slowly. Corresponding theArmillaria rot reaches only a slight high in the stem. The conditions which promote theArmillaria rot are not yet known.

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Gef?rdert mit Hilfe von Forschungsmitteln des Landes Niedersachsen.—Dr.L. Dimitri, Dr.R. Siepmann undR. Kliefoth danke ich für ihre Mithilfe bei den Au?enarbeiten und bei den Pilzdiagnosen.     

Die Wirkung wäßriger Streuextrakte verschiedener Waldbäume auf Mycelwachstum und Konidiosporenkeimung von Fomes annosus (Fr.) Cke.

The effect of water extracts of leaf and needle litter from different forest trees on the mycelial growth and the germination rate of conidia of Fomes annosus (Fr.) Cke. Litter extracts from various forest trees and stands have distinct effects on mycelial growth and germination rate of conidia of Fomes annosus. The effects depend on concentration of the extract, period of extraction and on date of collecting the litter samples.     

Induced resistance of Norway spruce,variation of phenolic compounds and their effects on fungal pathogens

Three clones of Norway spruce (Picea abies) were studied for their response to mass‐inoculation with the blue‐stain fungus Ceratocystis polonica. The effect of different pretreatments (fungal inoculation and wounding) before mass‐inoculation was investigated for their possible role in an acquired resistance reaction. Pretreated trees showed enhanced resistance to the subsequent mass‐inoculation relative to control trees that received no pretreatment. Furthermore, the fungal colonization of inoculated trees was less than that of wounded trees. The phenolic content of the bark, analysed by RP‐HPLC, was compared in trees receiving different treatments. Trees inoculated with C. polonica had higher average concentration of (+)‐catechin, taxifolin and trans‐resveratrol than wounded trees. Both inoculated and wounded trees had higher average concentrations of these compounds than control trees. The effect of the phenolic extract of Norway spruce bark on the growth of the root rot fungus Heterobasidion annosum and the blue‐stain fungi C. polonica and Ophiostoma penicillatum were investigated in vitro. Heterobasidion annosum was not negatively affected, and the extracts had fungistatic effects on the blue‐stain fungi. The growth of O. penicillatum was more inhibited than the growth of the more aggressive C. polonica.     

Die Wirkung von Monoterpenen auf das Mycelwachstum von Fomes annosus (Fr.) Cooke

The effect of monoterpenes on the mycelial growth of Fomes annosus (Fr.) Cke. Four monoterpenes, singly and in mixture, were tested for their effect on the mycelial growth of Fomes annosus. Inhibition was caused by all the substances, the severity depending on material and concentration. The inhibition was not maintained over the entire study period.     

Le champignon mycorrhizien Gomphidius glutinosus,un puissant antagoniste de Fomes annosus en culture pure

Gomphidius glutinosus a powerful antagonist of Fomes annosus in pure culture. F. annosus isolated from spruce was strongly inhibited by Gomphidius glutinosus found under Picea abies. In presence of the pathogen, Suillus placidus, a very probable mycorrhizal fungus of Pinus cembra and a moderate antagonist of F. annosus, produces a yellow reacting antibiotic substance.