bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reduced fertilization capacity of SO2‐fumigated Picea omorika‐pollen
Authors: Krug Elke 
Published: June 2007

AbstractDry pollen of Picea omorika was fumigated with 820 μg/m3 SO2 for 3, 4, or 5 days. Few or no adverse effects occurred during subsequent in vitro germination: germination percentage was not affected at all, and reduction of the pollen tube length was only 10% in pollen exposed for 5 days.Nevertheless pollination with fumigated pollen resulted in reduced seed production. 41% fewer seeds per cone were produced, and only 33% were filled seeds, compared to 70% filled seeds of the control. Seed‐weight was reduced from 3.6 g per thousand in the control to 3.0 g per thousand, when cones were pollinated with pollen fumigated for 5 days. Similar but less striking effects were found with pollen fumigated for 3 or 4 days.
Incidence of Heterobasidion annosum in Norway spruce on a Mg‐Limed and Nonlimed Soil in the Black Forest, FRG
Authors: Skelly J. M. 
Published: June 2007

AbstractThe incidence of root disease was determined on Norway spruce in a mixed stand of spruce and fir near Alpirsbach (Northern Black Forest), Germany. Fifteen most symptomatic spruce were selected in each of two plots that had been limed with Mg‐containing lime termed “Hüttenkalk”, or nonlimed, in a previous trial to alleviate symptoms of yellowing and premature needle loss. No relationships were found between persistence of yellowing and needle loss on either plot and incidence of H. annosum.
Morphological studies of Lophodermium piceae (Fuckel) v. Höhnel on Norway spruce needles
Authors: Osorio M. , Stephan B. R. 
Published: June 2007

AbstractMorphological structures of the teleomorphous and anamorphous stages of the ascomycete Lophodermium piceae have been studied in detail. This fungal species is widely distributed and frequent on Norway spruce needles. The examination of many samples indicates that all belong to one species, namely L. piceae.
Effects of foliar nitrogen, potassium and magnesium concentrations on the resistance of Scots pine seedlings to Scleroderris canker infection
Authors: Ylimartimo Anneli 
Published: June 2007

Abstract Pinus sylvestris seedlings were grown in quartz sand and N, K and Mg were given in different ratios with the irrigation water. After growing season 50 % of the seedlings were inoculated with a conidial suspension of Gremmeniella abietina. The resistance of the seedlings to infection was studied by measuring the reduction of needle retention. K deficiency reduced the resistance. However, the effect of K was dependent on the amount of irradiance available in growth chamber after winter dormancy. In addition, deficient foliar K and Mg concentrations in combination, reduced the resistance of seedlings to infection.
Bursaphelenchus xylophilus induced pine wilt: Factors associated with resistance
Authors: Kuroda K. , Yamada T. , Ito S. 
Published: June 2007

AbstractWe investigated factors affecting resistance of Pinus spp. to Bursaphelenchus xylophilus. Nematode migration and multiplication was inhibited in resistant P. taeda. As a consequence acceleration of monoterpene synthesis terminated, tracheid‐cavitation did not become extensive, and xylemsap ascent was not significantly blocked. In P. strobus, inhibition of nematode activity was not as complete as in P. taeda, and temporal needle‐wilting was seen on some branches. Although this suggest some blockage of xylem water conduction, we were unable to confirm development of cavitation induced by nematode activity. β‐myrcene concentration in these species was not related to resistance.
Clones of Armillaria ostoyae and the pattern of infected juvenile lodgepole pine in Alberta, Canada
Authors: Klein‐Gebbinck H. W. , Blenis P. V. , Hiratsuka Y. 
Published: June 2007

AbstractSmall patches of dead trees were common among 7‐ to 15‐year‐oldPinns contortavar.latifoliain Alberta, Canada. The sizes of clones ofArmillaria ostoyae, determined by pairing diploid isolates, was larger than these patches. Pairing diploid isolates on strips ofBetula papyriferaprovided a clear indication of clonal relationships.
Variation in the levels of the antifungal stilbene glucosides astringin and isorhapontin in the bark of Sitka spruce [Picea sitchensis (Bong.) Carr.
Authors: Toscano Underwood C. D. , Pearce R. B. 
Published: June 2007

AbstractThe concentrations of the constitutive antifungal stilbene glucosides astringin and isorhapontin were measured in the bark of a number of Sitka spruce [Picea sitcbensis (Bong.) Carr.] genotypes. These included trees of different provenances, trees grown at different sites, and young clonal plants. The stilbene contents of individual trees or clones varied widely. In general this was attributable to variation between individual genotypes, and was not related to provenance or site.
Early detection of effects of acid deposition and automobile exhaust on young spruce [Picea abies (L.) Karst.] trees
Authors: Zaerr J. B. , Schill H. 
Published: June 2007

AbstractRooted spruce cuttings from three clones were sprayed daily with sulfuric acid at pH 2.5 for one month or treated with automobile exhaust for one hour. Foliage samples were extracted and analyzed by high performance liquid chromatography. Chromatographic peaks representing unidentified leaf constituents from treated and control trees were compared. Discriminant analysis indicated a weak but significant difference and Canonical discriminant analysis indicated clear differences between treatments and control. Similar differences were found between the three clones. Visible symptoms of damage were not evident even four months after treatment. This result is important because it demonstrates the possibility of using unidentified plant constituents to detect damage to plants even before visible symptoms appear.
Perspectives of disease threat in large‐scale Pinus radiata monoculture ‐ the New Zealand experience
Authors: Chou C. K. S. 
Published: June 2007

AbstractLarge scale P. radiata monoculture has been in existence in New Zealand for over 60 years. During this time a number of damaging diseases (e. g. Sirex‐Amylostereum, Dothistroma, Armillaria, Cydaneusma needle cast. Sphaeropsis die‐back etc.) have occurred but the impact was by no means devastating as these diseases are either controllable or in some the losses were deemed acceptable. As a large proportion of the biomass produced before age 10–12 is waste‐thinned, the acceptable level of disease loss is thereby very high. The practice of clear felling and short rotation reduces some of the disease risks common in other forest systems. Outlook for future disease threat is discussed with respect to current trends toward clonal forestry and the possible arrival of additional exotic pathogens.
Mechanism of cavitation development in the pine wilt disease
Authors: Kuroda K. 
Published: June 2007

AbstractVolatile terpenes increase in xylem tissue after infection of Pinus thunbergii with the pine wood nematode (Bursaphelenchus xylophilus). The role of these terpenes in traeheid cavitation, which blocks xylem‐sap ascent and leads to water deficit in pine trees, was assessed. Volatile terpene concentration increased long before initiation of tracheid cavitation. After the volatile terpenes reached the highest concentration, severe cavitation developed. Direct injection of α‐pinene into healthy pine trunks formed artificial cavitation in xylem. These observations support the hypothesis that excessively produced volatiles, which are hydrophobic and have lower surface tension than water can promote tracheid cavitation in pine wilt disease.
Water stress: A predisposing factor in the pathogenesis of Hypoxylon mediterraneum on Quercus cerris
Authors: Vannini A. , Scarascia Mugnozza G. 
Published: June 2007

Abstract Hypoxylon mediterraneum (De Not.) Mill. proved to be a weakness parasite on Quercus cerris. Evidences are given about the association between pathogenicity of the fungus and water stress of the host.
Pathogenic variation in Cylindrocladium quinqueseptatum causing leaf blight of Eucalyptus1
Authors: Sharma J. K. , Mohanan C. 
Published: June 2007

AbstractA wide range of pathogenic variation was observed among the five isolates of Cylindrocladium quinqueseptatum leaf blight (CLB) which could be distinguished as different physiologic strains on 11 differential provenances of Eucalyptus. Susceptibility ranking of different provenances to five isolates also differed significantly indicating differential interaction between isolates and provenances. Analysis of variance showed that CLB severity of a provenance is mainly governed by the genetically different isolates and also that the provenances have closer genetical relationship. The results provide the first evidence for the existence of physiologic strains in C. quinqueseptatum.
Pathogenic variability of various isolates of Seiridium cardinale, S. cupressi and S. unicorne inoculated on selected Cupressus clones and seedlings
Authors: Xenopoulos S. G. 
Published: June 2007

AbstractComparative studies of the pathogenicity of eight isolates of three Seiridium species were carried out by stem inoculations on Cupressus sempervirens and C. glabra seedlings and clones. Seiridium cardinale and S. cupressi caused bigger and more severe cankers than all strains of S. unicorne. During the first nine months after inoculation, the canker length of S. cardinale was larger than the cankers of S. cupressi. However, during the second year after inoculation, S. cupressi cankers were larger and more severe than those of 5. cardinale.
Oak decline: I. Fungi associated with various disease symptoms on overground portions of middle‐aged and old oak (Quercus robur L.)
Authors: Kowalski T. 
Published: June 2007

AbstractFungi colonizing overground portions of Quercus robur art presented separately for each of the following types of disease symptoms: leaves with atrophy and necrotic areas, dead branches, dead tops of branches, dead water sprouts, local necrotic areas in bark and phloem, locally dead and discoloured sapwood in debarked places, local discolorations inside sapwood, extensive nec‐rotic areas on stems, dead trees. Over 80 species of fungi were found in all, mainly from As‐comycotina and Deuteromycotina. Connected with each type of symptom there were several species of fungi which were more frequent than the remaining ones. In most cases fungi seem to be of secondary importance in development of symptoms characteristic for oak decline.
Markstrahlenkrankheit der Buche (Fagus sylvatica): Anatomische Beschreibung und mogliche Entstehungsursache
Authors: Von Kučera L. J. , Bonsen K. J. M. 
Published: June 2007

AbstractThe beech ray disease, an abnormal structure of the rays associated with discolorations, is de‐scribed macroscopically as well as microscopically. A SEM study indicated the presence of bac‐teria, which apparently influence the activity of the cambial tissue.
Variation in the susceptibility of lodgepole pine provenances to Sirococcus shoot blight: results from artificial inoculations
Authors: Hamelin R. C. , Sutherland J. R. 
Published: June 2007

AbstractFourteen provenances of lodgepole pine artificially inoculated with a local isolate of Sirococcus strobilinus varied in their susceptibility to the pathogen. Provenances from the Dry Interior (31.9%) and the Sierra (14.3%) had significantly lower disease incidence than those from the Interior Wet Belt (51.9%), the Coast (62.5%) and the Cascade Range (58.6%). These results indicate the potential for selecting seed sources with low levels of susceptibility to Sirococcus shoot blight.
Disease history of Gremmeniella abietina in a Pinus sylvestris stand
Authors: Kaitera J. , Jalkanen R. 
Published: June 2007

AbstractA new method has been developed for studying the history of Gremmeniella abietina infection in Scots pine (Pinus sylvestris) stands. The branch analysis method is based mainly on the occurrence of necrotic cankers and scars caused by G. abietina in annual shoots of branches. The supporting factors are the number of leader changes of branches and branch death model.
Scanning electron microscopy of mycoparasitism of Armillaria rhizomorphs by species of Trichoderma
Authors: Dumas M. T. , Boyonoski N. W. 
Published: June 2007

AbstractScanning electron microscopy showed that Trichoderma polysporum, T. harzianum and T. viride were mycoparasites on the rhizomorphs of Armillaria gallica. These Trichoderma species attacked and penetrated the melanized outer tissue of the rhizomorph and once inside they killed the Armillaria hyphae by coiling and direct penetration. After one week the rhizomorphs infected with each of the three species of Trichoderma were devoid of hyphae.
Lophodermium piceae and Rhizosphaera kalkhoffii in fallen needles of Norway spruce (Picea abies)
Authors: Livsey Susan , Barklund Pia 
Published: June 2007

AbstractFalling needles collected from under individual 70‐year‐old Norway spruce (Picea abies) trees for about four years were checked for fungal fruitbodies. The most common fungi were Lophodermium piceae and Rhizosphaera kalkhoffii. Maximum frequencies of fruitbodies occurred in late autumn for L. piceae (ca. 80% of the needles), in summer for R. kalkhoffii (ca. 60%) and in winter for the third most common fungus, Tiarosporella parca (ca. 10%). The frequencies of needles with fruiting fungi varied greatly within and between years. This is the first report of T. parca from Sweden.
Antagonistic effects of saprophytic bacteria to Dothichiza populea
Authors: Avramović G. , Arsenijević M. 
Published: June 2007

AbstractBacteria were isolated from both poplar and other plant species. Antagonistic effects of these bacteria on growth and germination of Dothichiza populea were tested. A total of 195 bacterial isolates were collected, but only 12 isolates from poplars and 31 isolates from other hosts distinctly reduced growth of D. populea in dual cultures. Some of these growth inhibiting isolates were also examined for their influence on germination of pycnospores. Only some bacterial isolates from poplars inhibited germination, whereas others even stimulated it. On the other hand, all isolates from other hosts than poplars significantly reduced germination rate.
Cellulose is degraded during phloem necrosis of Hevea brasiliensis
Authors: Nicole M. , Chamberland H. , Nandris D. , Ouellette G. B. 
Published: June 2007

AbstractA cytochemical investigation was performed for studying cellulose alteration during phloem necrosis of the rubber tree. An exoglucanase‐gold complex was used for localizing β‐(1,4)‐D‐glucan linkages of non reducing ends of the polymer. Variation in cell wall labelling indicates that cellulose is degraded during this disease and suggests that cellulases are involved in this alteration. Wall appositions and periplasmic vesicles were also observed.
Penetration of Cronartium flaccidum into pine needles
Authors: Ragazzi A. , Fedi Irene Dellavalle 
Published: June 2007

AbstractThe penetration of Cronartium flaccidum into the cotyledons, primary needles and secondary needles of Pinus pinaster and P. nigra var, laricio was investigated.SEM examination showed that the fungus did not form appressoria and that the germ tube penetrated directly into the stomata.
New type of damage to Quercus ilex: pollen germination and hydration ability
Authors: Bellani Lorenza M. , Paoletti E. 
Published: June 2007

AbstractPollen grains collected from trees of Quercus ilex L. belonging to different classes of new type damage were analyzed. Five parameters were taken into account: viability, germinability, tube lengthening, grain volume of the dehydrated state and after rehydration. Damage to mother plants clearly influences the above mentioned parameters, causing a reduction in pollen grain viability, germinability, and in the ability of the grains to rehydrate.
Electrophoretic protein profiles of strains of Ceratocystis fimbriata f. sp. platani
Authors: Granata G. , Parisi A. , Cacciola S. O. 
Published: June 2007

AbstractSoluble proteins extracted from the mycelium of strains of Ceratocystis fimbriata (Ell. et Halst) Davidson f. sp. platani Walter were separated on native and SDS‐polyacrylamide gradient gel electrophoresis. The protein patterns were compared and the electrophoretic profiles of all the strains examined showed striking intraspecific similarities. The use or protein banding patterns as a diagnostic criterion to distinguish strains of C. fimbriata is discussed.
Viruslike particles associated with ringfleck mosaic of mountain ash and a mosaic disease of raspberry in the Bavarian Forest
Authors: Ebrahim‐Nesbat F. , Izadpanah K. 
Published: June 2007

AbstractTwo types of spherical viruslike particles measuring ca. 25–30 nm and 80 nm in diameter, respec‐tively, were found both in ringfleck mosaic affected mountain ash and adjacent raspberry bushes in the Bavarian Forest. The smaller particles were also found in symptomless mountain ash in the same forest. The sap from infected mountain ash reacted with an antiserum to tomato spotted wilt virus in agar‐gel‐diffusion test. No reactions were obtained with raspberry or mountain ash sap when tested against antisera to a number of small spherical plant viruses.
Stilbenes and resin acids in relation to the penetration of Heterobasidion annosum through the bark of Picea abies
Authors: Lindberg M. , Lundgren L. , Gref R. , Johansson M. 
Published: June 2007

AbstractConcentrations of the stilbene glucosides astringin and isorhapontin, which ranged from 5 to 50 mg/g fresh weight in Picea abies bark, decreased in response to in vivo infection with the root‐rot fungus Heterobasidion annosum. The initial concentration of the stilbene astringin was negatively correlated with the depth of hyphal penetration. Resin acid contents increased following infec‐tion, but were not correlated with the depth of hyphal penetration. The spatial distribution of stilbene glucosides in spruce stem, root collar and root bark, and the seasonal variations in con‐centration, were estimated.
Observations on some Italian provenances of Melampsora populnea
Authors: Naldini B. , Longo N. , Drovandi F. , Gonnelli T. , Moriondo F. 
Published: June 2007

AbstractIn some Italian provenances of Melampsora populnea on Populus tremula from mountain zones, the presence of Melampsora pinitorqua was tested through teliospore germinability tests and sub‐sequent basidiospore inoculations. In this study the risk of twist rust epidemics in new planta‐tions is discussed.
Endophytische Pilze in Blättern und Zweigen von Quercus petraea
Authors: Von Halmschlager E. , Butin H. , Donaubauer E. 
Published: June 2007

Abstract Endophytic fungi in leaves and twigs of Quercus petraea. Surface sterilized leaf and twig samples taken in 1989 from sessile oak (Quercus petraea) in Austria yielded host‐specific as well as unspecific ubiquistic endophytes. In leaves, Aureobasidium apocryptum and Apiognomonia quercina were the most frequent taxa, while Colpoma quercinum was the dominant species in twigs. The colonization rates of individual species were subjected to seasonal variation.
Histopathology of loblolly pine needles infected by Mycosphaerella dearnessii, the brown‐spot needle disease pathogen
Authors: Jewell F. F. 
Published: June 2007

AbstractThe histopathology of green Pinus taeda needles infected with Mycosphaerella dearnessii was investigated. Cellular abnormalities observed were predominately the collapse of mesophyll cells within the limits of the symptom lesions. The epidermis, hypodermis, endodermis, transfusion tissue, and the vascular system within the lesions were not affected. Resin ducts exhibited cell necrosis and dissolution within and distal from the visible limits of lesions. An intercellular interface was present in non‐collapsed mesophyll cells at lesion limits, and the lateral extension of the interface usually corresponded to the effects observed in resin ducts distal from the lesions. Non‐stromatic hyphae were rare in and distal from lesion tissue, indicating the host tissues were affected in advance of the pathogen. The production of a toxin by M. dearnessii is suspected.
Reproductive success of Bursaphelenchus xylophilus and B. mucronatus at constant and fluctuating temperatures
Authors: Tomminen J. 
Published: June 2007

AbstractReproductive rates of three North American isolates ofBursaphelenchus xylophilusand a Finnish isolate ofB. mucronatuswere compared by culturing the nematodes at constant and at daily fluctuating temperatures in the laboratory and in the field.Botrytis cinereaandPinus sylvestriswood were used as nutrient sources. In general, theB. xylophilusisolates reproduced better than theB. mucronatusisolate at constant temperatures, whereas the situation was reversed at fluctuating temperatures.
Spatial and temporal characteristics of canopy gaps caused by Armillaria root disease and their management implications in lowveld forests of South Africa
Authors: Lundquist J. E. 
Published: June 2007

AbstractRoadside reconnaissance and aerial photo surveys were used to characterize the frequency and size of canopy gaps caused by Armillaria root disease in 1763 stands of Pinus spp. in the eastern Transvaal, South Africa. Root disease occurred in 290 stands, most of which grew at altitudes 1000 m. Pinus elliottii was the most commonly infected host, followed by P. kesiya, P. roxburghii, P. caribaea, P. taeda, and P. patula. Disease severity (proportion of stand area with gaps) increased rapidly to age 3, remained nearly constant between ages 6–17, increased rapidly again between 17–28, and then decreased abruptly between ages 28–40. Gap incidence (proportion of all stands with gaps) rapidly increased to age 10, after which it remained nearly constant. Host species present in previous stands influenced whether disease developed in current stands.
Growth of Gremmeniella abietina on artificial media simulating the effects of mineral nutrient imbalance of Scots pine
Authors: Ylimartimo Anneli , Haansuu P. 
Published: June 2007

AbstractIncreased foliar N/K and N/Mg ratios are known to reduce the resistance of Pinus sylvestris to scleroderris canker caused by Gremmeniella abietina. The aim of this work was to study how such changes in nutrient levels affect the growth of the pathogen in vitro. The mycelium of the pathogen was grown on artificial media adjusted to simulate the changes in inorganic N, K, Mg and Ca and free amino acid concentrations in the host with nutritional imbalance. Increased concentrations of K and Ca reduced the mycelial growth of the pathogen, whereas a modest increase in the concentration of inorganic N increased the growth. Tenfold concentrations (compared with normal host levels) of arginine and glutamic acid, and up to one hundred‐fold concentrations of proline increased the mycelial growth. The results suggest, that nutrient imbalances may enhance the colonization of host tissues by G. abietina.
Susceptibility of four conifer species to Gremmeniella abietina
Authors: Aitken Elizabeth A. B. 
Published: June 2007

Abstract G. abietina causes severe dieback in pole‐stage stands of Scots pine in Britain. The susceptibility of ll provenances of Scots pine and of three other conifer species was tested by inoculations. Significant differences in susceptibility were found amongst Scots pine provenances, with those originating from a native Scottish pinewood at Loch Maree showing the highest levels of disease. Corsican pine was shown to be the most susceptible species tested although sporulation was greatest on Scots pine. Norway spruce was also shown to be susceptible when inoculated late in the growing season. Infection in lodgepole pine was negligible. High levels of β‐phellandrene were tentatively linked with resistance among trees in a single stand of Scots pine.