bluuebunny/crossref_metadata_2025_split huggingface dataset:
Testing Fraxinus excelsior, Fraxinus americana, and Fraxinus pennsylvanica for resistance to Pseudomonas syringae subsp. savastanoi pv. fraxini
Authors: Van Dam B. C. , Van Der Voet H. 
Published: June 2007

AbstractEight clones ofFraxinus excelsior, one clone ofF. americanaand one clone otF. pennsylvanicawere tested for their susceptibility to bacterial knot disease by artificial inoculations. Parametric and non‐parametric methods of statistically analysing their resistance were compared.
Effects of ammonium and nitrate on mycorrhizal seedlings of Pinus sylvestris1
Authors: Termorshuizen A. J. , Ket Petra C. 
Published: June 2007

AbstractThe effects of ammonium sulphate and sodium nitrate on Pinus sylvestris seedlings inoculated with Paxillus involutus and Suillus bovinus were investigated. Weekly fertilization (26 weeks) positively affected the plant dry weight, but inhibited the mycorrhizal formation and decreased the root length/weight ratio. Ammonium treatments affected the seedlings more positively and the mycorrhizas more negatively than nitrate did. The effects on seedlings inoculated with P. involutus were more pronounced than on those inoculated with S. bovinus. The possible mechanisms of the effects of nitrate and ammonium on mycorrhizas are discussed.
Cryphonectria cubensis, a potential pathogen of Psidium guajava in South Africa
Authors: Swart W. J. , Conradie E. , Wingfield M. J. 
Published: June 2007

AbstractThe pathogenicity of an isolate of Cryphonectria cubensis was tested in artificial inoculations on Eucalyptus grandis, Psidium guajava and Syzygium cordatmn. The isolate was able to colonize host tissue of all three species following inoculations of branch sections. It rapidly colonized the tissue of potted guava plants of the important commercial cultivar, Fan Relief and resulted in the death of a number of inoculated branches. Pathogenicity was also proven on mature guava trees in the field. An important implication of these findings is that the cultivation of guavas in South Africa could be confronted with a potentially severe disease problem in the future.
Occurrence of mycoplasma‐like organisms in diseased and non‐symptomatic alder trees (Alnus spp.)
Authors: Lederer W. , Seemüller E. 
Published: June 2007

AbstractMycoplasma‐like organisms (MLOs) were detected in almost all examined trees of Alnus glutinosa and A. incana older than approximately 5 years. The minority of trees showed symptoms of decline while the others appeared healthy. MLOs were also found in A. glutinosa var. barbata, A. hirsuta, A. rubra, A. rugosa, A. subcordata, and A. tenuifolia.
Effect of an ectomycorrhizal fungus, Laccaria laccata, on Fusarium damping‐off in Pinus banksiana seedlings
Authors: Chakravarty P. , Hwang S. F. 
Published: June 2007

AbstractDamping‐off caused by Fusarium oxysporum Schlecht in Pinus banksiana Lamb, was reduced significantly when inoculated with an ectomycorrhizal fungus, Laccaria laccata (Scop. ex Fr.) Berk. and Br. In paired culture, growth of F. oxysporum was significantly reduced by L. laccata. The number of colony forming units of F. oxysporum was reduced significantly in the rhizosphere of P. banksiana seedlings when inoculated with L. laccata. Spore germination and germ tube length of F. oxysporum was inhibited strongly by culture filtrate of L. laccata and root exudate of P. banksiana inoculated with L. laccata. Mycorrhizal seedlings had significantly higher amount of total soluble phenols than nonmycorrhizal ones.
Bacteria wilt of Casuarina equisetifolia in India
Authors: Ali M. I. Mohamed , Anuratha C. S. , Sharma J. K. 
Published: June 2007

Abstract Pseudomonas solanacearum (Smith) was consistently isolated from the wilted plants of Casuarina equisetifolia. The isolate gave positive reaction to oxidase, catalase and gas production from nitrate and negative reaction for arginine dihydrolase and acid was produced from various carbohydrates. Wilt produced on tomato, egg plant and capsicum indicated that the pathogen belongs to Race I and Biovar III of P. solanacearum which is a new record from India.
Chestnut blight (Cryphonectria parasitica) north of the Swiss alps
Authors: Bissegger M. , Heiniger Ursula 
Published: June 2007

AbstractChestnut blight (Cryphonectria parasitica) was found in several stands in the Swiss plateau. At each site only one or two compatibility (vc) groups were present. The vc‐group I was the most common. At a heavily infested site also young oaks (Quercus petraea) were infected.
Detection of xylan hydrolyzing activity in culture extracts of Gremmeniella abietina
Authors: Petäistö R.‐L. , Talvinen J. , Kajander E. O. 
Published: June 2007

AbstractHemicellulose xylan is a major non‐cellulose component of wood. Xylan hydrolyzing activity was detected in culture media of G. abietina. G. abietina grew well on xylan. Pine needle extract decreased xylanase activity.
Antagonism of two decay fungi, Peniophora polygonia and Phellinus tremulae associated with Populus tremuloides
Authors: Chakravarty P. , Hiratsuka Y. 
Published: June 2007

AbstractInteractions between the two most common decay fungi of Populus tremuloides, Peniophora polygonia and Phellinus tremulae were studied. Pe. polygonia inhibited the growth of Ph. tremulae when grown in paired culture. The presence of a culture of Pe. polygonia reduced the growth of Ph. tremulae in a volatile metabolite test. A culture filtrate of Pe. polygonia reduced the growth of Ph. tremulae in liquid culture. The growth of both the fungi was inhibited, and they formed a dark brown line at contact point when grown on a Po. tremuloides block.
Tannase activity associated with growth of Cryphonectria parasitica on American and Chinese chestnut extracts and properties of the enzyme
Authors: Farias Graciela M. , Elkins J. R. , Griffin G. J. 
Published: June 2007

Abstract Cryphonectria parasitica grew on American and Chinese chestnut total aqueous and tannin extracts from winter and summer bark. Differences in the amount of conidial germination and growth on extracts of the two species were small. C. parasitica tannase (tannin acyl hydrolase) was found to be more abundant intracellularly, had a pH optimum of 5.5, and a temperature optimum for activity of 30°C. Total tannase activities on American chestnut total aqueous and tannin extracts were higher than on the respective Chinese extracts.
Mating system and apothecia production in Gremmeniella abietina
Authors: Uotila A. 
Published: June 2007

AbstractMycelia of Gremmeniella abietina isolated from the same ascus were paired in seedlings of Pinus sylvestris and the production of apothecia determined. G. abietina was found to be a heterothallic fungus in which mating is controlled by a single locus composed of at least two mating allcles. Independent of climatic conditions isolates of type B produced greater number of apothecia than those of type A.
Isolation of Xanthomonas campestris pv. populi from stem lesions on Salix matsudana X alba ‘Aokautere’ in New Zealand
Authors: Haworth R. H. , Spiers A. G. 
Published: June 2007

AbstractA yellow‐pigmented, Gram‐negative, aerobic, salicin utilising bacterium‐identified as Xanthomonas campestris pv. populi was isolated from one year old stems of S. matsudana X alba‘Aokautere’ willows exhibiting stem necrosis. Although the bacterium was isolated from necrotic stem tissue almost in pure culture it was not pathogenic to vigorously growing material of S. matsudana X alba‘Aokautere’ in field inoculations. Stress and predisposing climatic conditions during winter (frost, rain, wind, mild temperatures) are thought to have favoured the initial infections of this opportunistic pathogen. This disease is not considered serious.
Relative susceptibility of Eucalyptus provenances to Cylindrocladium leaf blight in Kerala, India1
Authors: Sharma J. K. , Mohanan C. 
Published: June 2007

AbstractSusceptibility of 46 provenances belonging to 16 species of Eucalyptus to Cylindrocladium leaf blight caused by Cylindrocladium quinqueseptatum, C. clavatum and C. ilicicola differed significantly in detached leaf inoculations. Generally, susceptibility of a provenance to the three species of Cylindrocladium showed significant differences; only a few provenances gave either equally resistant or susceptible reactions to all the three species. C. clavatum was the most virulent species, C. ilicicola the least and C. quinqueseptatum intermediate.
Seasonal changes of soluble carbohydrates in mycorrhizas of Norway spruce and changes induced by exposure to frost and desiccation
Authors: Niederer M. , Pankow W. , Wiemken A. 
Published: June 2007

AbstractMycorrhizas of six spruces of a stand were collected over two years and were analysed for soluble carbohydrates (sucrose, raffinose, glucose, trehalose and mannitol). The level of these carbohydrates was high during winter and low during summer. Upon exposure of excised mycorrhizas to frost or desiccation, the content of trehalose roughly doubled. A positive correlation was found between the trehalose content of mycorrhizas and their ability to survive frost or desiccation as determined by the electrolyte leaching method.
Susceptibility of Eucalyptus grandis to Cryphonectria cubensis
Authors: Conradie E. , Swart W. J. , Wingfield M. J. 
Published: June 2007

AbstractArtificial inoculation of rooted Eucalyptus grandis cuttings with Cryphonectria cubensis in the glasshouse showed that significant differences exist in the susceptibility of various Eucalyptus clones to the pathogen. A 61.3% difference in susceptibility was observed between the most resistant and susceptible group of clones. Results appeared, however, to have been influenced by genotype × environment interaction.
Clonal response in Salix to Melampsora rusts in short rotation coppice plantations
Authors: McCracken A. R. , Dawson M. 
Published: June 2007

AbstractThe appearance of Melampsora spp. rust on a range of Salix spp. clones used for short rotation coppice was recorded. The progress of the disease and its subsequent effect on leaf fall was also recorded. Rust pustules from all the clones described were examined using the Stereoscan Elec‐tron Microscope. This revealed no differences in uredospore architecture which could be consis‐tently related to host.
S and P intersterility groups in Heterobasidion annosum; Infection frequencies through bark of Picea abies and Pinus sylvestris seedlings and in vitro growth rates at different oxygen levels
Authors: Lindberg M. 
Published: June 2007

AbstractSeedlings of Norway Spruce and Scots Pine were inoculated with S and P strains of the root rot fungus Heterobasidion annosum. Infection frequencies through the living bark layers were not related to subgroup affiliation in neither spruces nor pines. Growth rates in vitro were not related to growth rates in vivo. Oxygen concentration had a stronger effect on the growth rates of P than on S strains.
Trunk inoculations of Phytophthora cinnamomi in red oaks
Authors: Robin Cécile 
Published: June 2007

AbstractTrunks of northern red oaks were inoculated with Phytophthora cinnamomi. To study lesion growth in bark tissues over several years, lesion assessment methods were perfected and tested. Koch's postulates were demonstrated. Development and longevity of lesions were studied. Intra‐specific variability of red oak susceptibility was investigated.
Die natiirliche Astreinigung und ihre biologischen Voraussetzungen VI. Versuche zum Holzabbau durch Astreiniger‐Pilze
Authors: Von Butin H. , Kowalski T. 
Published: June 2007

Abstract Natural pruning of branches and its biological conditions. VI. Survey of wood degradation by branch inhabiting fungi. Laboratory tests demonstrated that fungi occurring on decaying branches and probably associated with natural pruning of branches are capable of degrading wood. Most fungi tested positive for the Bavendamm‐reaction and therefore produce phenol‐oxidase. The inoculation of wood blocks caused a typical soft rot. Impact‐resistance tests showed that fungi involved in natural pruning of branches can considerably reduce strength of wood.
Der pH‐Wert und das Vorkommen niedermolekularer Fettsäuren im Naßkern der Buche (Fagus sylvatica L.)
Authors: Von Walter M. 
Published: June 2007

Abstract The pH‐value and the occurrence of fatty acids in wetwood of European Beech (Fagus sylvatica L.). At the border of the wetwood area pH‐value of the capillary liquid was altered from acid to neutral conditions. Fatty acids frequently occurred in wetwood. Probes with pH‐values higher than 6.8 often were deeply black stained.
Reproductive success of Bursaphelenchus xylophilus and B. mucronatus under Finnish summer temperature conditions
Authors: Tomminen Jyrki 
Published: June 2007

AbstractThe objectives of this study were to determine the reproductive potential and the time required for completion of the life cycle of Bursaphelenchus xylophilus under Finnish summer temperature conditions. The reproductive success of B. xylophilus was compared with the potential of a Finnish isolate of B. mucronatus. The latter appeared more successful in reproduction particularly when cultured on Finns syhestris wood.
Genetics of field resistance to Melampsora in Salix viminalis
Authors: Gullberg U. , Ryttman H. 
Published: June 2007

AbstractThe inheritance of resistance to Melampsora. spp. on Salix viminalis, the variation in resistance over space and time, and rust infection rate in relation to the geographic origin of the host was studied. The analysis showed that there was considerable additive genetic variation for rust resistance, that the results did not have high repeatability over space and time, and that the material from southernmost Sweden was most sensitive to the rusts occurring in south Sweden.
Effect of nitrogen and carbon sources on lignin and cellulose degradation by Armillaria ostoyae
Authors: Entry J. A. , Donnelly PaulaK. , Cromack K. 
Published: June 2007

AbstractLignin has been hypothesized to be the primary mechanism of resistance to fungal pathogens in plant tissue. Degradation of lignin and cellulose by Armillaria ostoyae cultured for six weeks in Melin‐Norkrans medium containing various nitrogen and carbon sources was measured radiometrically. No consistent pattern of lignin or cellulose degradation was found, regardless of A. ostoyae isolate, nitrogen source and concentration, or carbon concentration. More lignin was degraded as the concentration of glucose and fructose increased but not when the concentration of sucrose increased.
Effects of some seed‐borne fungi on Picea glauca and Pinus strobus seeds
Authors: Mittal R. K. , Wang B. S. P. 
Published: June 2007

AbstractEffects of inoculations of nine fungi to prechilled and nonchilled seeds of Picea glauca and Pinus strobus were studied in unsterilized and sterilized nursery soils, and a peat‐vermiculite‐perlite mixture. All the fungi demonstrated weak pathogenicity to seeds.
Susceptibility of different Eucalyptus genotypes to artificial leaf‐inoculations with Cylindrocladium scoparium and C. clavatum
Authors: Blum L. E. B. , Dianese J. C. 
Published: June 2007

AbstractYoung plants of 38 Eucalyptus seed sources were inoculated in the laboratory with conidia of Cylindrocladium scoparium and C. clavatum. Susceptibility was principally assessed in terms of the severity of leaf spotting.
Sur un cas de variabilité chez Sphaeropsis sapinea
Authors: Morelet M. , Chandelier P. 
Published: June 2007

Abstract A case of variability in Sphaero sis sapinea. Two isolates (type I and type II) of Sphaeropsis sqinea were isolated from the co lar of a declining Cedrus deo daa in the South of France. Cultural characteristics on PDA and MEA as well as conidial dimensions were compared with those of types A and B of S. sapinea described to occur in North America.Type II was similar to type A in respect to cultural aspects and growth but distinctly different in conidial dimensions. Slower growing type I was similar to type B. However, type I grew faster on PDA, had smaller conidia and lacked microconidia. Single‐conidia isolates obtained from the four types showed stability of these characteristics.
Impact of molecular biology on forest pathology: A literature review
Authors: Hubbes M. 
Published: June 2007

AbstractRapid developments in the field of molecular biology have produced a number of very powerful analytical tools by unifying techniques of genetics, biochemistry and cell biology. As reviewed in the present paper, these tools will become important and indispensable in forest pathology studies of the genetic machinery and regulatory mechanisms that control fungal products implicated in the complex tree‐pathogen interactions. Understanding these interactions will enhance the development of efficient control methods of forest pathogens.
Pathogenicity studies with Bursaphelenchus mucronatus in Scots pine in Finland
Authors: Tomminen Jyrki 
Published: June 2007

AbstractThe objective of the study was to determine the role of FinnishBursaphelenchus mucronatusas a possible pathogen in Scots pine,Pinus sylvestris, under Finnish ambient weather conditions. Small seedlings and young field grown trees were used as inoculation targets. The results suggested the nematode being of minor importance as a tree pathogen in Finland.
Mycorrhizal associations of Sitka‐spruce seedlings propagated in Irish tree nurseries
Authors: Grogan H. M. , O'Neill J. J. M. , Mitchell D. T. 
Published: June 2007

AbstractThe mycorrhizas of Sitka‐spruce seedlings propagated in two bare‐root nurseries and one container nursery in Ireland are identified and compared. In the bare‐root nurseries, Piceirhiza horti‐inflata was the most frequent mycorrhizal association during the first year of growth but appeared to be replaced by Hebeloma sp. and Amphinema byssoides in 2‐year‐old seedlings. There was a greater diversity of mycorrhizas on container‐grown seedlings which included Thelepbora terrestris, Hebeloma sp. and Piceirhiza guttata.
Long‐term survival of Bursaphelenchus xylophilus in living Pinus sylvestris in an established plantation
Authors: Halik S. , Bergdahl D. R. 
Published: June 2007

AbstractScots pines (Pinus sylvestris) in a 20‐year‐old plantation in northern Vermont, USA, were inoculated with the pinewood nematode (Bursaphelenchus xylophilus) in 1987. To determine how long B. xylophilus would survive after inoculation, the trees were periodically observed and sampled for the nematode up to the end of 1993. The nematode was still found to persist in living, healthy‐appearing pines 6 years after inoculation.
The use of needle‐trace method (NTM) in retrospectively detecting Lophodermella needle‐cast epidemic
Authors: Jalkanen R. , Aalto T. , Kurkela T. 
Published: June 2007

AbstractThe recently developed needle‐trace method (NTM) was successfully used to verify retrospectively the occurrence of a well‐documented needle‐cast epidemic caused by Lophodermella sulcigena in the 5‐year period of 1977–1981 in a stand of Pinus sylvestris.
Did climatic warming trigger the onset and development of yellow‐cedar decline in southeast Alaska*
Authors: Hennon P. E. , Shaw C. G. 
Published: June 2007

AbstractYellow cedar (Chamaecyparis nootkatensis) is a valuable tree species that is experiencing an extensive forest decline on over 200000 ha of unmanaged forest in southeast Alaska. Biotic factors appear secondary and some abiotic factor is probably the primary cause of this naturally occurring decline. A warming climate, which coincided with the onset of extensive tree mortality about 100 years ago, may have triggered one of the possible abiotic causes such as freezing damage and/or soil toxicity.
Glucanohydrolase enzyme activity in embryos of Scots, Corsican and lodgepole pines infected in vitro with Heterobasidion annosum
Authors: Nsolomo V. R. , Woodward S. 
Published: June 2007

AbstractEmbryos of Scots pine (Pinus sylvestris), Corsican pine (P. nigra var. maritima) and Lodgepole pine (P. contorta) were infected in vitro with Heterobasidion annosum and the activities of 1,3‐β‐glucanase, chitinase and β‐glucosidase were monitored. Both the infected and control embryos of the three pine species showed the presence of the enzymes. Statistical analysis showed no significant increase (P > 0.05) in the levels of 1,3‐β‐glucanase in infected embryos for all the three pine species. However, there was a significant increase in levels of chitinase in infected embryos of P. contorta and P. nigra var. maritima and also in levels of β‐glucosidase in infected embryos of all three of the pine species. The study has therefore revealed that constitutive levels of glucanohydrolase enzymes exist in the embryos of the three pine species and that the induction of chitinase and β‐glucosidase was a factor in the response of the embryos to stimulation by H. annosum infection.
The occurrence and pathogenicity of uni‐ and binucleate Rhizoctonia and Pythiaceae fungi among conifer seedlings in Finnish forest nurseries
Authors: Lilja A. 
Published: June 2007

Abstract Uni‐ and binucleate Rhizoctonia and Pythiaceae fungi were isolated from roots of dieback seedlings. Only binucleate Rhizoctonia strains were present in the roots of healthy seedlings. In pathogenicity tests, uninucleate Rhizoctonia sp. were pathogenic and binucleate Rhizoctonia spp. non‐pathogenic. Pythium ultimum var. ultimum and Phytophthora undulata were the only Pythiaceae fungi that killed 12‐week‐old seedlings.
Histology of witches' brooms on Betula pubescens
Authors: Jump B. A. , Woodward S. 
Published: June 2007

AbstractWitches' brooms caused by Taphrina betulina on Betula pubescens formed from the development of large numbers of axillary shoots on infected buds. Broom shoots showed vigorous growth during the first season, but died in the second or third year after initiation. Occasional adventitious root production was noted at the base of broom shoots. Cortex and secondary phloem tissues of the central gall‐like structure of the brooms expanded. The bark of infected material lacked brachysclereids, and tangential ray parenchyma of the secondary phloem were also absent. Numerous shoot bases and aborted axillary buds were present within the bark. Abundant starch granules were present, especially in the phellogen and phelloderm layers. Distortion of the internal lignified tissues was due to the presence of multiple vascular connections from the proliferation of shoots on the broom.
Breakdown of barrier zones and prediction of the spread of discolouration and decay resulting from stem wounds in Eucalyptus regnans and E. obliqua
Authors: White D. A. , Kile G. A. 
Published: June 2007

AbstractIn Eucalyptus regnans and E. obliqua a rapid increase in the spread of defects (discolouration and decay) was observed more than 14 years after wounding. This increase was due to a breakdown of the barrier zone and the subsequent spread of defects into wood formed after wounding. Satisfactory relationships predicting defect extent using time since wounding could not be derived.
Evaluation of Dutch elm disease susceptibility and pathogenicity of Ophiostoma ulmi using micropropagated elm shoots
Authors: Dorion N. , Bigot C. , Neumann P. 
Published: June 2007

AbstractElm (Ulmus sp.) shoots from in vitro micropropagated plants were tested with Ophiostoma ulmi culture filtrates, at different dilutions to determine the susceptibility of different host clones to Dutch elm disease (DED). ‘Commelin’, a susceptible Dutch hybrid, showed a high wilting index but that of American elm was higher. Although U. pumila × japonica (Sapporo gold 2) was the most tolerant to spore inoculation, its wilting index was as high as that of ‘Commelin’. The absorption capacity and wilting index of the elm shoots showed consistent correlation to isolate effectiveness (as determined by inoculation experiments), to production of toxin (cerato‐ulmin) and to filtrate dilution. This method could be used to assess the effectiveness of the different O. ulmi isolates and for the detection of elm genotypes that are highly susceptible to Dutch elm disease.