bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chitin and glucans detected in the cell walls of Pythium dimorphum—an oomycetous fungus
Authors: Asiegbu F. O. , Lönneborg A. , Johansson M. 
Published: June 2007

SummaryWith aid of fluorescein isothiocyanate (FITC) and gold‐labelled lectins, together with antibodies against chitinase and β‐1,3‐glucanases, the spatial distribution of chitin and glucans in hyphal walls of Pythium dimorphum, a causative agent of root die‐back disease of conifer seedlings was studied. Contrary to previous reports, this study revealed that chitin, a polymer of N‐acetyl‐d‐glucosamine, is a component of the cell wall of this oomycetous fungus. However, compared with the other amino sugar, N‐acetyl‐galactosamine, it is not present in significant amounts. Ultrastructural and labelling studies demonstrated that the chitin region is embedded in or masked by glucan residues.
Identification and characterization of the phytoplasma associated with elm yellows in southern Italy and its relatedness to other phytoplasmas of the elm yellows group
Authors: Marcone C. , Ragozzino A. , Seemüller E. 
Published: June 2007

SummaryIn the neighbouring regions Basilicata, Campania, and Calabria of southern Italy, diseased trees of European field elm (Ulmus minor) were examined for phytoplasmal infection using polymerase chain reaction (PCR) technology. All affected trees examined tested positively. Using a primer pair specific for the EY phytoplasma group and restriction fragment length polymorphism (RFLP) analysis of PCR‐amplified ribosomal DNA, the organism detected was identified as the elm yellows (EY) phytoplasma. RFLP analysis of PCR‐amplified ribosomal DNA was also employed to attempt differentiation within the EY group which includes, in addition to the EY agent, phytoplasmas infecting Rubus, alder, eucalypts, Spanish broom, and grapevine. Following separate digestion with AluI, RsaI, Sau3AI, MseI, HhaI, and KpnI, all PCR‐products from EY‐group phytoplasmas examined had similar RFLP profiles. When the same ribosomal DNA fragments were digested with TaqI restriction endonuclease, three different restriction profiles were detected among the EY‐group phytoplasmas. These profiles represented, respectively, (1) the EY phytoplasma (2) the phytoplasmas causing rubus stunt and being associated with alder yellows, spartium witches broom, and eucalyptus little leaf, and (3) the flavescence dorée phytoplasma. RFLP analysis using TaqI endonuclease enabled for the first time the differentiation of the phytoplasmas associated with alder yellows, eucalyptus little leaf, and spartium witches broom from the EY agent.
Resinicium bicolor; a potential biological control agent for Heterobasidion annosum
Authors: Holmer L. , Stenlid J. 
Published: June 2007

SummaryAfter introductory competition tests in the laboratory, Resinicium bicolor was used as a potential control agent for the conifer root rot fungus Heterobasidion annosum. Greenhouse pathogenicity tests with R. bicolor on 4‐year‐old seedlings of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) showed moderate incidence of infection. In three places in Sweden, four test areas were chosen for field experiments in first‐rotation plantations and also in old forest sites of Norway spruce. Wood blocks, pre‐inoculated with one strain of R. bicolor, were buried in the soil beside stumps at 0, 1, 2, 3 and 4 months after thinning using various spatial designs. In two of the test areas, half of the stumps were treated with a suspension of H. annosum conidia from one strain by surface spraying. After 2–3 years, stump roots were investigated and the length of growth of both species were noted. The identity of mycelia reisolated from and wood debris in the test areas were confirmed by somatic compatibility tests with the original strains. The strain of R. bicolor released was recovered from all over the test area; the released H. annosum strain was only reisolated from the conidia sprayed stump roots. R. bicolor had little effect on the growth and occurrence of H. annosum. Potential control of disease spread may arise, however, from occlusion of the pathogen from outer parts of roots.
Dry weight loss of wood after the inoculation of Scots pine stumps with Phlebiopsis gigantea
Authors: Sierota Z. H. 
Published: June 2007

SummaryArtificial inoculation of stumps with Phlebiopsis gigantea (preparation‘PgIBL’) against Heterobasidion annosum in Scots pine (Pinus sylvestris) stands on former agricultural lands in Poland is being performed throughout the year. The practical efficiency of the biological control appears to be influenced by the moisture content in stumps and roots. In experiment 1, dry weight loss of wood 3 months and 6 months after P. gigantea inoculation in laboratory was investigated in the stumps after salvage cutting (felling of dead and dying trees) and after thinning (routine cutting of trees) and compared with the decay of the artificially inoculated stumps under field conditions. It was found that 6 months after inoculation the dry weight loss of the samples was about 3%, 17% and 22%, respectively. In experiment 2, the decay of wood from horizontal roots collected after thinning, inoculated with P. gigantea in laboratory, was evaluated. Three months after the inoculation, the loss of dry weight wood was about 22–52%, depending on initial moisture of the roots.
Aeciospores ofCronartium flaccidum, C. ribicolaandEndocronartium pinishow no differences in morphology
Authors: Kasanen R. 
Published: June 2007

SummaryThe morphology of the aeciospores of the pine stem rust fungiCronartium flaccidum, Cronartium ribicolaandEndocronartium pini, collected from nine locations in Finland, Sweden and Italy, was compared. Surface structures of 900 aeciospores were visually classified using a scanning electron microscope, and dimensions of 1100 aeciospores were measured from micrographs. The data grouping was tested with discriminant analysis. The spores had well‐defined smooth areas and annulate warts on their surface.E. pini, C. flaccidumandC. ribicolacould not be distinguished by the surface structures of the spores. The grouping of spores by dimensions into sample locations was statistically significant by one discriminant function, while the grouping into species was not. The observed similarities corroborated the current views on the close relationship ofC. flaccidum and E. pini.
Estimation of dispersal gradients of S‐ and P‐type basidiospores of Heterobasidion annosum
Authors: Möykkynen T. , von Weissenberg K. , Pappinen A. 
Published: June 2007

SummaryThe number of airborne deposits of the root pathogen Heterobasidion annosum was counted with a wood disc method at distances 5–1000 m from one S‐type and one P‐type infection centre in stands of Picea abies in June, July and August, 1995. The level of background deposition in the area was determined in four healthy control stands. Based on intersterility group determination of deposits, only measurements within 100 m of the infection centres could be used in estimations of dispersal gradients owing to confusion with background deposition. A power law gradient model adequately described the reduction of deposits with increasing distance from the infection centres. Gradients were fairly similar in four directions around the infection centres as the wind speeds were low (3.2m/s) during the collection periods. The gradients were steeper around the P‐type centre, probably due to its lower spore production capacity. The background deposition level (2.8 colonies/m2× h) was reached at distances 1255 m and 98 m from the S‐type and P‐type centre, respectively.
Detection of cherry leaf roll nepovirus (CLRV) in birch, beech and petunia by immuno‐capture RT‐PCR using a conserved primer pair
Authors: Werner R. , Mühlbach H.‐P. , Büttner C. 
Published: June 2007

SummaryViruses in woody forest plants are known to be difficult to detect owing to phenolic compounds in plant extracts and an often irregular distribution of the pathogens within the plants. We describe a modified immunocapture reverse transcription polymerase chain reaction (RT‐PCR) to detect cherry leaf roll virus (CLRV) in forest trees. The application of a conserved primer pair is shown to be suitable for the detection of different isolates of CLRV from birch from distant forest stands in Germany and also in strains of CLRV from other host plants, including beech, walnut and petunia hybrids. The CLRV isolates and strains could be distinguished by direct sequencing of their PCR products. CLRV was easily detectable throughout the year in tissue of male inflorescences, leaf buds, leaves, single seeds, cortical tissues of young twigs and also in single aphids and bugs (Kleidocerys resedae) collected from a CLRV‐infected birch‐ tree.
Growing clonal mixtures of willow to reduce effect of Melampsora epitea var. epitea
Authors: McCracken A. R. , Dawson W. M. 
Published: June 2007

SummaryRust (Melampsora epitea var. epitea) is the single most limiting factor in the production of biomass from short rotation coppice willow. The use of fungicides is unacceptable for economic, environmental and practical reasons. Consequently, clonal mixtures were investigated as an alternative disease control strategy. At one of two sites Salix × dasyclados, Salix burjatica ‘Korso', S. burjatica‘Germany’, Salix viminalis‘Bowles Hybrid’ and S. viminalis‘683’ were included in the clonal mix. At the second site six clones were used. These were as above with the exception of S. burjatica‘Korso’ and including, Salix × calodendron, Salix mollissima‐undulata‘SQ83’. At both sites all clones were also planted in monoclonal stands. Throughout each growing season disease levels were recorded on individual clones, both in monoclonal stands and mixtures. Fungicide treatments were included to compare their effectiveness to mixtures in reducing disease impact. Growing willow in mixed clonal stands delayed the onset of disease, slowed its build up and resulted in lower disease levels at the end of the growing season. These reductions in disease impact contributed to the increased yields obtained from clonal mixtures and were generally comparable to those achieved with fungicides.
A method for quantifying changes in the epicuticular wax structure of Norway spruce needles
Authors: Trimbacher C. , Egkmullner O. 
Published: June 2007

SummaryA method for quantifying changes in the epicuticular wax structure of spruce needles (Pieea abies) has been developed for the scanning electron microscope. This evaluation system, based on a five‐point scale, classifies only the epistomatal waxes of current‐year needles. Two criteria, the different crystal wax forms and the amount of changed wax as a percentage of the total stomatal area have been used for classification. Statistically significant results (accuracy below ± 10% at 5% error level) were obtained under the following conditions. Mixed needle samples were taken from two adjacent trees per site. These were in a dominant and predominant social position in the stand. The needles were collected from the 7th whorl of sun crowns exposed to all wind directions. The wax quality was determined by evaluating three stomata per needle. One stoma was investigated at the needle base, one m the middle and the third at the apex of the needle. 24 needles were evaluated per site.SEM‐Investigations of needle waxes of 25 Austrian forest sites with no local emission source (background sites) showed, that the mean wax quality ranged from 1.6 to 4.1, according to this classification method. Stepwise multiple regression analyses with site characteristics and element contents of the needles (nutrient elements, heavy metals) confirmed correlations between the wax quality and the manganese‐ and sulphur‐content of the needles and also the average degree of crown defoliation.
Development of fruiting bodies of large tree type of Gremmeniella abietina var. abietina and timing of infection on Scots pine inn northern Finland
Authors: Kaitera J. , Hantula J. , Jalkanen R. 
Published: June 2007

SummaryThe formation and maturing of the large tree type Gremmeniella abietina var. abietina fruiting bodies and their sporulation were investigated for 3 years on Scots pine (Pinus sylvestris) in northern Finland. This was done by monthly assessment of shoots in the field and in the laboratory. Infection caused by G. abietina var. abietina was dated on Scots pine by monthly covering with pollination bags and exposing branches during the growing season. Pycnidia appeared between August and September, 1 year after infection, and they started to release conidia between late June and early July, 2 years after infection. Fresh pycnidia and microconidia were formed during the following August and September in the infected shoots. The causal large tree type of G. abietina var. abietina did not produce apothecia on branches within 3 years of infection. Monthly covering and exposing branches showed that infection took place mainly between June and July.
Dodder transmission of alder yellows phytoplasma to the experimental host Catharanthus roseus (periwinkle)
Authors: Marcone C. , Ragozzino A. , Seemuller E. 
Published: June 2007

SummaryThe alder yellows phytoplasma (ALY) was transmitted to the experimental host Catharanthus roseus (periwinkle) via dodder (Cuscuta odorata) bridges from naturally infected alder trees. The identity of the dodder‐transmitted phytoplasma has been confirmed by restriction fragment length polymorphism (RFLP) analyses of polymerase chain reaction (PCR)‐amplified ribosomal DNA.
Variability in pathogenicity ofMelampsora allii‐populinaexpressed on poplar cultivars
Authors: Frey P. , PlNON J. 
Published: June 2007

SummaryA collection of 42 isolates ofMelampsora allii‐populinawas established. Fourteen isolates were collected from various poplar cultivars over several French localities and 28 isolates from the alternate hosts(Alliumspp.,Arumspp. andMuscari comosum)obtained from nature or after inoculation. These isolates were inoculated in the laboratory on a large range of poplar cultivars belonging to several species. No isolate proved pathogenic on all cultivars and many qualitative interactions were observed between isolates and cultivars. This is the first evidence for the existence of physiological races within this fungus. No link was found between pathogenicity on poplar and on the alternate hosts.Among the inoculated cultivars, at least three were susceptible to all isolates (Beaupre, Candicans and Robusta), whereas the following showed qualitative reactions to the inoculated isolates: Altichiero, Carpaccio, Cima, Fritzi Pauley, I 154, Isieres, Luisa Avanzo, NL 2842, Rap and Spijk. Race‐specific resistance toM. allii‐populina(i.e. resistance to some races of the pathogen, but not to the others) has been found in two North American species(Populus deltoidesandPopulus trichocarpa)which have never coevolved with this fungus. The results are discussed in comparison withMelampsora larici‐populina.
Phylogenetic analysis of Japanese Armillaria based on the intergenic spacer (IGS) sequences of their ribosomal DNA
Authors: Terashima K. , Cha J. Y. , Yajima T. , Igarashi T. , Miura K. 
Published: June 2007

SummaryTo determine the phylogenetic positions of two new species, Armillaria jezoensis and Armillaria singula, and one new subspecies, Armillaria mellea suhsp. nipponica, the nucleotide sequences of the intergenic spacers (IGS) of their ribosomal DNA were investigated, and compared with those of tour other Armillaria species from Japan, and those of nine Armillaria species from Europe and North America. We conclude that Armillaria jezoensis, and Armillaria singula belong to the Armillaria gallica cluster as Armillaria cepistipes, Armillaria gallica and Armillaria sinapina from Japan. Two isolates of Armillaria ostoyae from Japan were placed within the Armillaria ostoyae cluster. Armillaria mellea subsp. nipponica had an IGS sequence as long as the IGS of Armillaria mellea from Europe and North America. However, the IGS sequences of Armillaria mellea subsp. nipponica, whose basidium base lacks a clamp connection could not be satisfactorily aligned with the IGS sequences of other species possessing this morphological feature.
Review of oak stand decline with special reference to the role of drought in Poland
Authors: Siwkcki R. , Ufnalski K. 
Published: June 2007

SummaryDeclines in oak‐forest ecosystems have been reported frequently throughout the world since the beginning of this century. They have been associated with the death of individual trees, of small groups of trees or of entire stands. In this paper, the phenomenon of oak decline is presented in the context of the local site conditions in selected countries. Oak decline is regarded as a result of the synergistic action between damaging agents, both biotic and abiotic. Periodic changes of the climate in selected experimental plots of Quercus robur stands in Poland were analysed by comparing Walter's climatic diagrams and annual growth rings. Climatic conditions have a major influence on the vigour of oaks. An increase in the frequency of dry years (especially when drought occurs at the beginning of the growing season, e.g. in May‐June) has contributed to the complex phenomenon of oak decline.
A decline‐model interpretation of genetic and habitat structure in oak populations and its implications for silviculture
Authors: Steiner K. C. 
Published: June 2007

SummaryOak decline is attributable to predisposing conditions of both biotic and abiotic origin, arid to numerous insects, pathogens, and abiotic events that act as intermediate or ultimate agents of mortality. The precise causal factors vary with circumstances, but the fundamental role of the tree genotype in the process appears to be one of predisposition. Trees are predisposed to oak decline when they are genetically incapable of surviving the stresses natural to the habitats they occupy. Quercus rubra is discussed as a ease study for which there is a considerable amount of genetic and ecological information. This species is characterized by (1) unusual sensitivity in growth to small‐scale environmental heterogeneity and (2) unusually high levels of within‐population variation in growth rate. Using growth rate as the best‐available surrogate measure of ecological fitness, it is clear that high levels of genetic variability are important, even necessary, for the ecological success of populations of this species. Differential adaptation of genotypes to microsites within even very small areas is likely. To minimize susceptibility to oak decline, forest practices should favour (1) the maintenance of high levels of genetic variation, (2) the use of local provenances in artificial regeneration, and (3) large seedling populations. A further implication is that high rates of seedling mortality in plantations may be normal and even desirable for long‐term forest health.
Gloeosporidina platani sp. nov., the spermatial state of the anthracnose fungus Apiognomonia veneta (Sacc. & Speg.) Höhn.
Authors: Butin H. , Kher R. 
Published: June 2007

SummaryA new species of the coelomycetous genus Gloeosporidina found on leaves of Platanus × hispanica in Germany is described and illustrated. Culture trials and RAPD patterns demonstrate that the fungus is a part of the developmental cycle of Apiognomonia veneta, the cause of sycamore anthracnose. The relationship between Gloeosporidina moravica and Apiognomonia quercina on oak and between Gloeosporidina sp. and Apiognomonia errabunda on beech is described. The maintenance of the Apiognomonia spp. discussed as separate species is warranted because of differences in spermatial size among the Gloeosporidina states.
Comparison of bluestain fungi grown in vitro and in freshly cut pine billets
Authors: Uzunovic A. , Webber J. F. 
Published: June 2007

SummaryBoth moulds and bluestain fungi cause serious economic losses and much research is aimed at finding environmentally and economically acceptable methods of control. Despite this, there has been little study of the growth of these fungi in freshly cut wood unaltered by drying or sterilization and which therefore resembles the substratum normally invaded under natural field conditions. Thus, the growth of six sapstain fungi was compared at 20°C in freshly cut pine billets and on three types of artificial media (MEA, TWA and Pine Sapwood agar). The fungi comprised Ceratocystis coerulescens, Leptographium wingfieldii, Ophiostoma minus, Ophiostoma piceae, Phacidium coniferarum and Sphaeropsis sapinea. The six species varied markedly in their linear growth rate on agar media. In pine billets, they extended at different rates in longitudinal, radial and tangential directions, showing different pathogenic ability and patterns of colonization. Some species appeared to be ‘xylem preferring’ while others colonized the phloem tissue more readily. The growth of C. coerulescens in pine billets was very rapid (19.4 mm/day) and on average was more than twice as fast as on MEA, suggesting it was strongly stimulated by living pine tissue. The fungi also tended to grow more slowly in logs cut between autumn and spring compared with those harvested in mid‐ to late summer.
Increased testicular 8‐hydroxy‐2′‐deoxyguanosine in patients with varicocele
Authors: Ishikawa Tomomoto , Fujioka Hitoshi , Ishimura Takeshi , Takenaka Atsushi , Fujisawa Masato 
Published: June 2007

OBJECTIVESTo assess immunohistochemically 8‐hydroxy‐2′‐deoxyguanosine (8‐OHdG, a sensitive biological marker of oxidative damage and stress) in testicular tissue from patients with varicocele, to determine whether 8‐OHdG is related to spermatogenesis, as oxidative stress in testicular DNA is associated with poor semen quality and reduced fertility.PATIENTS, SUBJECTS AND METHODSTesticular tissue samples were collected from the testes of 36 patients with varicocele and five normal volunteers. The mean (sd) age of the patients was 35.3 (5.4) years. The prevalence of immunostained germ cells among all the germ cells in >20 seminiferous tubules was calculated.RESULTSThe mean (sd) sperm concentration and Johnsen’s score in the varicocele group was lower than in the normal group, at 27.6 (11.8) vs 80.4 (21.7) million/mL (P < 0.001) and 7.6 (1.1) vs 9.0 (0.7), respectively (P < 0.05). In all patients, 8‐OHdG was mainly expressed in the spermatogonia and spermatocytes in the seminiferous tubule. Immunostained germ cells correlated negatively with sperm concentration (r = −0.48, P = 0.01) and Johnsen’s score (r = −0.46, P = 0.02), but not with follicle‐stimulating hormone, luteinizing hormone or testosterone level. Immunostained germ cells were significantly more prevalent in the varicocele group, at 53.6 (5.7)%, than that in the normal group, at 14.3 (2.3)% (P < 0.001). The prevalence of immunostained germ cells and clinical grades were positively related; the ratio recorded for varicocele grades I, II and III was 38.0 (10.0)%, 41.0 (9.1)%, and 57.0 (9.3)%, respectively (grade I vs grade III, P < 0.05).CONCLUSIONSIncreased 8‐OHdG expression in the testis was associated with deficient spermatogenesis in infertile men with varicocele.