bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vegetative compatibility and conversion to hypovirulence among isolates of Cryphonectria parasitica from northern Italy
Authors: Garbelotto M. , Frigimelica G. , Mutto‐Accordi S. 
Published: June 2007

AbstractIsolates of Cryphonectria parasitica from chestnut trees in forest stands and commercial orchards were tested for virulence, distribution in vegetative compatibility (v‐c) groups, and capacity of being converted to hypovirulence through acquisition of double‐stranded RNA determinants from five hypovirulent isolates. Even though 77% of the virulent isolates were converted to hypovirulence, the low retrieval of hypovirulent isolates and the relatively high v‐c diversity in our study area warrant further investigation.
Intersterility groups of Heterobasidion annosum in some spruce and pine stands in Byelorussia, Lithuania and Estonia
Authors: Korhonen K. , Bobko I. , Hanso S. , Piri T. , Vasiliauskas A. 
Published: June 2007

Abstract Heterobasidion annosum isolates were collected from spruce, pine and mixed stands growing on forest and former agricultural soils. Intersterility groups of the isolates were identified. Pine was attacked by the P group only and spruce mostly by the S group. Frequency of the P group on spruce was higher on old forest soils and in mixed spruce and pine stands. Based on its in vitro compatibility with the F group, the S population in Byelorussia and Lithuania is more closely related to the Finnish S population than to the Alpine S population of H. annosum.
The effect of site preparation and fertilization on the severity of Phaeoseptoria eucalypti on Eucalyptus species
Authors: Nichol Nicola S. , Wingfield M. J. , Swart W. J. 
Published: June 2007

AbstractThe effect of site preparation and fertilization on the susceptibility of Eucalyptus species to Phaeoseptoria eucalypti was examined. There was no significant difference in disease rating between plough and terrace treatments which consistently yielded trees that attained greater heights and possessed a denser foliage. These trees were also less susceptible to P. eucalypti than those associated with other forms of site preparation. Trace element application reduced the incidence of disease as did the application of 50 % fertilizer at planting and 50 % when trees were 6 months old as opposed to the second half being applied when trees were 3 months old.
Identification and partial characterization of an extracellular manganese‐dependent peroxidase in Armillaria ostoyae and Armillaria mellea
Authors: Robene‐Soustrade I. , Lung‐Escarmant B. , Bono J. J. , Taris B. 
Published: June 2007

AbstractLaccase and manganese‐dependent peroxidase (Mn peroxidase) activities were detected in the culture media of Armillaria ostoyae and A. mellea. Mn peroxidase was produced in significantly higher quantity by the A. ostoyae isolates and was purified by chromatography from one isolate of this species. Some properties of the purified enzyme were examined (absorption spectrum, H2O2 and MnSO4 optimal concentrations, pH optimum and lactate stimulation). Enzymes of potential importance in the lignin degradation (especially Mn peroxidase) by Armillaria sp. are compared to those of other root‐rotting fungi. The possible role of Mn peroxidase in modulating the pathogenicity of Armillaria sp. is discussed.
Effect of endophytic fungi from oak (Quercus robur L.) on mortality of leaf inhabiting gall insects
Authors: Butin H. 
Published: June 2007

AbstractObservations in the field suggest that certain species of endophytic fungi which occur, but are normally dormant, in the leaves ofQuercus roburcan be stimulated to pathogenic development by the feeding activity of certain gall insects. As a result of the death of leaf tissue the gall is also killed. This antagonistic relationship between endophytic fungi and gall insects is illustrated in the following three examples:Kabatiella apocrypta / Trioza remota, Gloeosporium quercinum / Neuroterus numismalisandDichomera saubinetii / Polystepha panteli.
Field evidence for the large pine weevil, Hylobius abietis as a vector of Heterobasidion annosum
Authors: Kadlec Z. , Starý P. , Zumr V. 
Published: June 2007

AbstractMycological analysis of the excrements of adult weevils (Hylobius abietis L.), trapped in the baited pitfall traps in South Bohemia, Czechosovakia, demonstrated the presence of viable spores which suggest a positive role of the weevils as vectors of H. annosum.
Gremmeniella abietina, Phacidium infestans, and other causes of damage in alpine, young pine plantations in Norway
Authors: Roll‐Hansen F. , Roll‐Hansen Helga , Skroppa T. 
Published: June 2007

AbstractField studies of damage and mortality were carried out through 16 years in six young plantations, mostly of Pinus contorta, but also P. sylvestris and P. sibirica. Differences between pine species, P. contorta provenances, sites, and soil treatments are reported and discussed, as are influences of environment, climatic conditions, snow cover, and nutrient deficiency. Gremmeniella abietina was by far the most important cause of mortality; there were great differences between the sites as to development and seriousness. Other important causes of mortality and damage were Phacidium infestans, elk (Alces alces L.), voles, and snow pressure.
Resistance of Picea abies seedlings to infection by Heterobasidion annosum in relation to drought stress
Authors: Lindberg M. , Johansson M. 
Published: June 2007

AbstractNorway spruce (Picea abies) seedlings, 2–4 years old, were subjected to different degrees of stress. Drought stress affected the predisposition to infection by Heterobasidion annosum in the same way in root wood, stem wood and stem bark. At high water potentials (−3 to −5 bar) resistance was high, at intermediate levels (‐ 5 to ‐ 15 bar) it was low but increased again at water potentials below ‐ 8 to ‐ 15 bar. Neither light nor oxygen deficiencies appeared to have adverse effects on resistance. Total length of unsuberized roots was a sensitive indication of strain on the seedlings.
Fungal succession in sapwood of Norway spruce infested by the bark beetle Ips typographus
Authors: Solheim H. 
Published: June 2007

AbstractFungal invasion of Norway spruce sapwood was investigated during a period of 130 weeks fol‐lowing attack by the spruce bark beetle Ips typographus. Heavy beetle attack tended to overwhelm the trees quickly and no secondary resinosis was produced. Nonetheless, fungal penetration in the sapwood was initiated only slowly, although it accelerated during the fourth week after attack. Typically the leading edge of fungal penetration was a few millimeters in advance of the visible blue‐stain during the sapwood colonization. Fungi invaded the sapwood in a successional pattern with the most pathogenic species Ophiostoma polonicum first, followed by other beetle‐transmitted Ophiostoma and Graphium species. The later succession was probably influenced by sapwood moisture. Strong decaying white‐rotters invaded near the base of the trees, where sapwood moisture remained favourable, while cf. Trichoderma viride dominated in the drier parts or the trees.
The susceptibility of Scots pine seedlings to Gremmeniella abietina: effect of growth phase, cold and drought stress
Authors: Petäistö Raija‐Liisa , Kurkela T. 
Published: June 2007

AbstractThe effect of the growth phase of pine seedlings on the success of Gremmeniella infection was studied in both simulated and natural growing seasons. Also the effect of cold and drought stress on the success of the infection was studied.
Detection of the endophyte Discula umbrinella in buds and twigs of Fagus sylvatica
Authors: Toti L. , Viret O. , Horat Gisela , Petrini O. 
Published: June 2007

AbstractEndophytic fungi have been isolated from buds and twigs of beech trees collected at four different sites in Switzerland. Discula umbrinella. was recovered at high frequencies from the bud scales and the twig pieces contiguous to the buds, but was virtually absent from the rolled up leaves enclosed by the scales. In addition to infection by air‐borne inoculum, thalli of D. umbrinella may grow from the twigs into the leaf tissues.
Requirements and biological aspects of Fusarium eumartii and its possible role in oak decline in North‐eastern Italian oak forests
Authors: Ragazzi A. , Mugnai Laura , Moricca S. , Vagniluca S. , Dellavalle Irene 
Published: June 2007

AbstractTo determine a possible role of Fusarium eumartii in oak decline in different zones of Italy some requirements (temperature, substrates, pH) and some biological aspects (ability to produce phytotoxic metabolites, and pathogenicity) were studied in vitro and by inoculation tests on oak seedlings.
Stimulation of growth, sporulation, and potential staining capability in Ceratocystiopsis falcata
Authors: Kawchuk L.M. , Hutchison L.J. , Reid J. 
Published: June 2007

AbstractA procedure is described for the rapid extraction from the hyphomycete Gliocladiumroseum of a compound that stimulates growth, perithecial formation, and pigmentation in the mycelium of the wood‐inhabiting ascomycete Ceratocystiopsis falcata.
Factors influencing mansonone induction in elm callus by culture filtrate elicitors of Qphiostoma ulmi
Authors: YangIB D. , Jeng R.S. , Hubbes M. 
Published: June 2007

AbstractMansonone F (phytoalexin) production in elm callus induced by elicitors of Ophiostoma ulmi is affLited by cultural and experimental conditions. These factors include different fun gal isolates, fungal culture age, elicitor concentration, the time of elicitor treatment, the callus cu Ytured with or without light and the callus subculturing frequency.
Variation in Heterobasidion annosum detected by Random Amplified Polymorphic DNAs
Authors: Fabritius Anna‐Liisa , Karjalainen R. 
Published: June 2007

AbstractThe production of Random Amplified Polymorphic DNAs (RAPDs) by Polymerase Chain Reaction (PCR) was used to detect variation in the isolates of Heterobasidion annosum with various geographical origins. Specific RAPD products were detected for each of the intersterility groups: the European S, F, P and the North American S group. There was considerably more polymorphism found among European S than P isolates. The analysis of RAPDs was shown to be a simple and a fast way to generate DNA markers specific to the previously established intersterility groups and thus useful for diagnostic purposes.
The effect of wood moisture on infection of Sitka spruce stumps by basidiospores of Heterobasidion annosum
Authors: Redfern D. B. 
Published: June 2007

AbstractIn an inoculation experiment to test the effect of wood moisture content on infection of Sitka spruce (Picea sitchensis) stumps by basidiospores of Heterobasidion annosum, exposure to high rainfall increased infection in the heartwood and reduced sapwood infection compared to covered stumps. This was associated with a greater moisture content in both wood types. Within‐treatment variation in the amount of infection was high and it is suggested that endogenous factors in stumps may have a greater influence on infection than the environment or the availability of spores.
Dieback of poplar and willow caused by Pseudomonas syringae in combination with freezing stress
Authors: Ramstedt M. , ÅRström B. , von Fircks H. A. 
Published: June 2007

AbstractDieback of poplar and willow, grown in short‐rotation forestry plantations, was shown to be a result of Pseudomonas syringae infections in combination with freezing stress. Bacteria isolated from damaged poplar and willow trees at several sites in Sweden, identified as P. syringae, showed ice nucleationactive (INA) properties in laboratory tests. To confirm the effect of bacterial infection, five different P. syringae isolates were reinoculatcd into stems of Salix viminalis, S. dasyclados and Populus spp. in the greenhouse before application of sub‐zero temperature stress. Subsequent dieback of the shoots was observed. It is concluded that P. syringae is a Potentiall severe pathogen of willow and poplar.
A rapid method for screening potential biological control agents of wood decay
Authors: Schoeman M. , Webber J. , Dickinson D. 
Published: June 2007

AbstractSixteen isolates of microfungi, obtained from freshly felled pine, were screened for inhibitory activity on a number of wood‐decay basidiomycetes. The screening procedure employed a bi‐layer test which involved growing the potential biocontrol isolates on either agar medium or irradiated pine discs. The influence that the two different substrata had on subsequent inhibition of decay fungi may have important implications for the screening of isolates for biocontrol activity. The use of such techniques for screening biocontrol agents is discussed.
Susceptibility of Eucalyptus grandis provenances to a root rot associated with Ganoderma sculptrutum in Zimbabwe
Authors: Masuka A. J. , Nyoka B. I. 
Published: June 2007

SummaryWidespread cankering, gummosis, wilting and death of Eucalyptus grandis were first observed in Zimbabwe in 1956. Recent investigations have revealed the symptoms and deaths to be associated with infection by Ganoderma sculptrutum. Indigenous tree species, in particular Brachystegia spiciformis and Julbernardia globiflora, provide inoculum source for the fungus.A total of 170 half‐sib families in 23 provenances were assessed for symptoms and death associated with G. sculptrutum infection. There were statistically significant differences (p ≤ 0.001) in observed symptoms among families in a provenance. Provenance differences were not significant (p > 0.05). There were significant differences among provenances (p ≤ 0.05) and families (p ≤ 0.001) for death associated with G. sculptrutum. Differences among the four blocks were significant for both symptoms (p ≤ 0.01) and death (P ≤ 0.001). Family heritability estimates ranged from 0.00 (±0.82) to 0.79 (±0.13) for symptoms and from 0.00 bb (±0.82) to 0.75 (±0.14) for death.
Mycoflora associated with slash‐pine seeds from cones collected at seed orchards and cone‐processing facilities in the south‐eastern USA1
Authors: Fraedrich S. W. , Miller T. 
Published: June 2007

SummaryA diverse mycoflora was associated with slash‐pine seeds from cones obtained at seed orchards and cone‐processing facilities in the southeastern USA. Potentially pathogenic fungi, including Lasiodiplodia tbeobromae, Sphaeropsis sapinea, and Fusarium spp., were isolated from seeds of cones obtained at all locations. Fusarium proliferatum and F. semitectum were the Fusarium spp. most often associated with seeds; F. subglutinans was rarely isolated. Many other species of fungi were associated with seeds from all locations. Incidence of fungus‐damaged seeds ranged from 2 to 11% among collection sites. Disease incidence was found to increase during cone storage. Types of fungi and the incidence of fungus‐damaged seeds were similar for damaged/discoloured cones and apparently healthy cones. The potential for slash‐pine seeds to become colonized by pathogenic fungi, such as S. sapinea and the various Fusarium spp., could have important implications for the establishment of these fungi in forest‐tree nurseries, as well as their introduction into foreign countries.
Comparison of Gremmeniella abietina isolates from Pinus sylvestris and Pinus contorta in terms of conidial morphology and host colonization
Authors: Hellgren M. 
Published: June 2007

SummaryGremmeniella abietina isolates from Pinus contorta in northern Sweden produced, in vitro, shorter conidia with fewer septa compared with isolates from Pinus sylvestris in the southern part of the country. After mycelial inoculation of shoots with G. abietina isolates from both host species, the resulting necroses were longer in P. sylvestris than in P. contorta. Keeping seedlings in artificial mild winter climate or detaching shoots from the seedling before inoculation caused longer necroses. No host specificity in colonization was found. Isolates from P. sylvestris caused longer necroses than did isolates from P. contorta, and both types of isolates caused longer necroses in P. sylvestris than in P. contorta. The differences found between the two G. abietina populations probably reflect regional variation in the fungus.
The ecology of fungal cankers on Cupressus macrocarpa in southern England
Authors: Sánchez M. E. , Gibbs J. N. 
Published: June 2007

SummaryBark isolations from cankers on Cupressus macrocarpa in southern England yielded Seiridium cardinale, Pestalotiopsis funerea and Pestalotiopsis monochaetioides. The recovery pattern of the three fungi indicated that only S. cardinale was a primary pathogen; the two Pestalotiopsis species being secondary. Pathogenicity data obtained following the inoculation of C. macrocarpa branches with mycelium of the three fungi confirmed this view.No evidence of vegetative incompatibility was found in S. cardinale, but five vegetative‐compatibility (vc) groups were found in P. funerea and six in P. monochaetioides. Different vc groups of the two Pestalatiopsis species were often found in the same S. cardinale lesion, suggesting that a number of separate colonization events were involved. It is possible that this sometimes leads to complete replacement of the pathogen.
First report of Mycosphaerella dearnessii in Switzerland
Authors: Holdenrieder O. , Sieber T. N. 
Published: June 2007

SummaryBrown‐spot needle blight caused by Mycosphaerella dearnessii [syn. Scirrbia acicola; anamorphic state: Lecanosticta acicola (syn. Septoria acicola)] was observed for the first time in Switzerland. So far, the disease seems to be confined to planted Pinus mugo and Pinus uncinata near Zurich. Pinus sylvestris adjacent to diseased P. uncinata did not show any disease symptoms.
Fungi colonizing Scots‐pine cone scales and seeds and their pathogenicity
Authors: Lilja A. , Hallaksela A. M. , Heinonen R. 
Published: June 2007

SummaryFungi were isolated from the cone scales and seeds of Scots pine using plating on malt‐extract agar and/or the standard blotter method in a Jacobsen's apparatus. Alternaria alternata, Epicoccum purpurascens and Ulocladium atrum were isolated from damping‐off seedlings germinating on agar or filter paper, but, in pathogenicity tests with peat‐sand (1:3) growth substrate, they were not pathogenic. All the Fusarium species isolated were pathogenic in growth substrate. Some F. avenaceum colonies formed no aerial hyphae and they proved to be a mixed culture of the fungus, a fluorescent Pseudomonas sp., and a gram‐negative bacterium. The bacterial associates appeared to increase the pathogenicity of F. avenaceum. All the micro‐organisms tested were more pathogenic in sterilized than in unsterilized peat‐sand substrate.
Sugar‐beet chitinase inhibits the growth of a spruce pathogen
Authors: Susi A. , Mikkelsen J. D. , von Weissenberg K. , Nielsen K. K. 
Published: June 2007

SummaryThe inhibiting effect of sugar‐beet chitinase, a defence enzyme in plants, on the growth of the fungi Heterobasidion annosum and Gremmeniella abietina was examined. The enzyme inhibited the growth of H. annosum, but had no effect on G. abietina. The role of hydrolytic enzymes in defence is briefly discussed.
Changes in the level of phenols during needle development in Scots‐pine populations in a control and polluted environment
Authors: Kareolewki P. , Giertych M. J. 
Published: June 2007

SummaryChanges in the level of phenolic compounds in needles of young Scots‐pine (Pinus sylvestris trees of various provenances were studied in an environment polluted by sulphur dioxide and fluorine compounds, and in a control environment. An increase in the content of ortho‐diphenols (o‐dPh) and total phenols (TPh) was found in the First year of needle development. This increase was significantly greater in the plants from the polluted environment. Relative to levels in the control environment, the highest level of phenols in the polluted environment was found in 2‐year‐old needles, followed by 3‐year‐old and then 1‐year‐old needles.
Evaluation of superficial canker instability for hypovirulent Cryphonectria parasitica inoculated on American chestnut trees
Authors: Griffin G. J. , Griffin S. L. 
Published: June 2007

SummaryHypovirulent strains of Cryphonectria parasitica produced superficial cankers on American chestnut (Castanea dentata) that were unstable for superficiality after one winter. Some unstable cankers yielded C. parasitica isolates that had high virulence on American chestnut trees and were vegetatively incompatible with the original inoculated hypovirulent strain, whereas other unstable cankers yielded isolates that had low virulence and were vegetatively compatible with the original hypovirulent strain.
Influence of the Phytophthora isolate and the seed source on the development of beech (Fagus sylvatica) seedling blight
Authors: Werres S. 
Published: June 2007

SummaryPhytophthora cactorum, the causal agent of beech seedling blight, can kill Fagus sylvatica seedlings within a few days. Eight isolates of Phytophtbora cactorum and one isolate of Phytophtbora citricola were tested for their pathogenicity towards beech seedlings derived from eight different registered stands. The P. citricola isolate proved to be more aggressive than all the P. cactorum isolates, although there were significant differences among the latter. The influence of the seed source was less sever than that of the fungi. Regions of provenance generally had less influence on disease development than fungal isolate but differences in susceptibility among sources were important in the interaction between isolate and source.
Distribution of clones of Phellinus noxius in a windbreak on Ishigaki Island
Authors: Hattori T. , Abe Y. , Usugi T. 
Published: June 2007

SummaryThe distribution of clones of Phellinus noxius, the causal agent of brown root rot, was studied in a windbreak on Ishigaki Island of Japan. In total, 99 isolates obtained from infected trees of Calopbyllum inophyllum, Casuarina equisetifolia and Bauhinia racemosa were analysed by means of a somatic compatibility test on a sawdust‐rice‐bran medium, an antagonism test on PDA with guaiacol solution, and by esterase analysis with isoelectric focusing. Results obtained from the three methods were almost identical, although the somatic compatibility test was less precise than the other methods. Isolates from neighbouring infected trees belonged to the same clone in many cases. On plots of 150–400 m2, 1–5 clones were found. Single clones covered an area of up to 20 × 20 m. A total or 25 different clones were recognized within the sample sites. This suggested that multiple basidiospore infection existed in the site, although infection centres spread by vegetative growth across root contacts of neighbouring trees.
Fast methods for DNA extraction for PCR analyses from Heterobasidion annosum mycelium and Endocronartium pini aeciospores
Authors: Pappinen A. , Kasanen R. , Möykkynen T. , von Weissenberg K. 
Published: June 2007

SummaryThe extraction of DNA from mycelium of Heterobasidion annosum or aeciospores of Endocronartium pini could be done rapidly by homogenizing the fungal material in PCR‐compatible buffer in Eppendorf tubes with a disposable pestle mounted on an electric drill. The DNA yield with this method was relatively low but sufficient for PCR analysis with ITS‐specific primers. For large series of fungal samples this protocol provides a quick and cheap method of determining the intersterility groups of H. annosum or for specific primer studies on E. pini populations. The time needed for DNA isolation from E. pini aeciospores and H. annosum mycelium could be reduced by nearly 85% compared to the mortar‐and‐pestle protocol.By using a disposable pestle mounted on an electric drill and phenol‐chloroform as extraction solution, the yield of DNA was higher than with the mortar‐and‐pestle method with phenol‐chloroform as extraction solution. The quality of DNA was sufficient for both specific‐primer and RAPD analyses, but the more complicated extraction method with phenol was needed.