bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Melampsora rust on the growth and development of Salix burjatica‘Korso’in Northern Ireland
Authors: Dawson W. M. , McCracken A. R. 
Published: June 2007

AbstractThe impact of Melampsora rust on the growth of Salix burjatica‘Korso’was assessed. Comparisons were made between untreated plants and those where the disease had been partially controlled using fungicides. Fungicides delayed the onset of the disease and its effects on growth. Leaf loss was reduced whilst shoot growth and dry matter yields increased. The effect of secondary organisms was also reduced resulting in lower levels of shoot death in the following season.
Butt‐rot of Scots pine in Thetford Forest caused by Heterobasidion annosum: a local phenomenon
Authors: Greig B. J. W. 
Published: June 2007

Summary Heterobasidion annosum was found to be the main cause of decay in 50–60‐year‐old Scots pine in Thetford Forest in East England. On some sites, up to 15% of the trees could be suffering from H. annosum rot, with decay occasionally extending 2 m or more up the stem. Prior to this study, Scots pine had been considered as resistant to H. annosum butt‐rot in Britain, except in overmature trees.
Haustorial morphology of Cronartium conigenum in naturally infected cones of three Pinus species from Guatemala1
Authors: Rayachhetry M. B. , Webb R. S. , Kimbrough J. W. , Miller T. 
Published: June 2007

SummaryHaustorial morphology of the cone‐rust pathogen, C. conigenum, was investigated among naturally infected female strobili of three Guatemalan pines, P. maximinoi, P. pseudostrobus, and P. oocarpa. Among the three pine species, haustorial shapes and sizes were more variable in P. maximinoi and P. oocarpa than in P. pseudostrobus. The haustorial shapes and sizes were more variable in parenchyma cells of the cortex, xylem, and pith than in the cells in the phloem, xylem rays, and tracheids. The haustoria were also present in larger numbers in the parenchyma cells of the cortex, xylem, and pith than in phloem parenchyma cells and tracheids. In living cells, the tips of some haustoria were appressed to the host nuclei.
Identification of European Armillaria species by restriction‐fragment‐length polymorphisms of ribosomal DNA
Authors: Schulze S. , Bahnweg G. , Tesche M. , Sandermann H. 
Published: June 2007

SummaryIdentification of European Armillaria species using ribosomal DNA (rDNA) restriction‐fragment‐length polymorphisms (RFLPs) was studied. A total of 44 Armillaria isolates representing five European biological species were examined. Whole‐cell DNAs were digested with one or two (double digest) restriction endonucleases and probed with a cloned plasmid carrying one complete rDNA repeat copy of Saccharomyces carlsbergensis. Applying the restriction endonuclease Bgl II in combination with either Eco RI, Bam Hl or Hin dIII, it was possible to detect rDNA RFLPs allowing differentiation between all five European Armillaria species investigated in the study. The most conclusive results were obtained in the rDNA/Ava II RFLP pattern. All biological species showed unique Ava II banding patterns. Generally speaking, the interspecific similarities were around 42% and lower, indicating a distinct species separation.The analysis of rDNA RFLP patterns by a restriction‐enzyme‐rDNA‐probe combination (for instance, Ava II or Bgl II/Hin dIII; probe pMY 60) is a practical means of identifying European Armillaria species for further taxonomic, phylogenetic and host‐pathogen interaction studies.
Response of maple sapwood to injury and infection
Authors: Shortle W. C. , Smith K. T. , Dudzik K. R. , Parker S. 
Published: June 2007

SummaryIn sapwood challenge experiments in Acer rubrum, columns of discolouration initiated by wounding and inoculation with pioneer fungi (Cephalosporium sp., Phialophora sp.) were similar in size to untreated wounds. Inoculation with decay fungi (Pleurotus ostreatus, Trametes versicolor) produced larger columns of wound‐initiated discolouration. The removal of bark around a bore wound caused a significantly larger column to form compared to the sum of the columns inititiated by separate wounds. Stage‐I discoloured wood, not associated with obviously rotted wood, had concentrations of mobile cations and soluble phenols similar to sapwood. Stage‐II discoloured wood, spatially associated with rotted wood, was frequently bounded by a chemically distinct boundary layer and the discoloured wood contained significantly greater concentrations of mobile cations and soluble phenols than stage‐I discoloured wood.
Short‐term variation in ascospore release by Phacidium infestans on the needles of Pinus sylvestris
Authors: Kurkela T. T. 
Published: June 2007

AbstractAscospore release by Phacidium infestans was monitored with volumetric‐recording spore traps in Finland. Detached branches of Scots pine infected naturally during the previous winter were used as a spore source. Spores were trapped during two autumns with simultaneous recording of weather factors. Free water from rain or thawing of rime or snow on the needles was required to initiate the spore release. After the onset of rain, the number of spores reached its maximum in 4–6 h, while heavy rain decreased the liberation of spores into the air. The number of spores had a higher correlation both with relative humidity and with precipitation delayed 3–7 h than with current precipitation. Temperature did not directly affect the ascospore release. Only a few spores were trapped at temperatures below 0°C. The effect of wind on the release of spores was mainly negative, and indirect through decreasing humidity. No diurnal periodicity was detected in the spore release.
Wood‐rotting fungi on Nothofagus pumilio in Patagonia, Argentina
Authors: Cwielong P. P. , Rajchenberg M. 
Published: June 2007

SummaryThe presence of basidiomes of wood‐decay fungi on living lenga (Nothofagus pumilio) was investigated in seven forest stands in Patagonia (Argentinia). The following species accounted for 85% of the rots: Postia pelliculosa, Phellinus andinopatagonicus, Piptoporus portentosus, Aurantioporus albidus, and Serpula himantoides. Ph. andinopatagonicus and A. albidus cause characteristic white rots, while the other tree species cause unspecific, cubical brown rots. S. himantoides was associated with cords among the decayed wood fragments. One stand was investigated in detail. The volume of decayed timber on this plot was 75%. Postia pelliculosa and Ph. andinopatagonicus probably infected the trees through the roots as well as through the canopy, and accounted for 70% of the wood‐rots. Piptoporus portentosus probably infected only through the canopy, while A. albidus and S. himantoides did so through the roots. Only 12% of the trees showed no decay. From trees with decay, 36% were attacked by one fungal species, 35% by two species.
Veränderungen des Monoterpenspektrums in verletzten Fichtenwurzeln und ihre potentielle Bedeutung für die Resistenz gegenüberHeterobasidion annosum
Authors: Rieger S. 
Published: June 2007

SummaryChanges in composition of the monoterpene fraction in damaged roots of Norway spruce and the potential significance for resistance against Heterobasidion annosum
The composition of monoterpenes in undamaged and wounded roots of Norway spruce (Picea abics) was investigated, α‐ and β‐Pinene comprised at least 85%. of the total content in undamaged roots. The variation of the monoterpene fraction within roots and between roots of an individual tree was relatively small. Variations of the monoterpene fraction between trees were found. There were no qualitative differences between stem and roots except for sabinene, which was found in small amounts in the stem. Large quantitative differences between stem and roots were found in α‐ and β‐pinene content. In almost all trees, damaging the sapwood of roots caused an increase in the α‐pinene content combined with a decrease in the relative content of β‐pinenc and limonenc/β‐phellandrene. Two different types of traumatic reaction in heartwood could be distinguished. The possible significance of the traumatic reaction in the roots of spruce with respect to their resistance to H. annosum is discussed.
Long‐term damage on Scots pine caused by Gremmeniella abientina near a nickel smelter in the Kola peninsula
Authors: KAitera J. , Isaenva L. , Jalkanem R. 
Published: June 2007

SummaryThe history of damage caused by Gremmeniella abietina on 10 Scots‐pine trees (Pinus sylvestris) was studied near a nickel smelter in Tsuna, Russia. The most severely damaged area was located alongside a river. According to the results of branch analysis, the first sign of G. abietina infection occurred in 1937. During the following 4 decades, annual signs were few and they occurred at random. Most of the damage had appeared during the 1980s and the early 1990s. In terms of cankers, the peak occurred in the mid‐1980s, and in terms of scars and leader changes, the peak was in the late 1980s and early 1990s. Branch mortality and secondary Tomicus spp. attacks increased in the late 1980s and were at their highest level in the early 1990s. The high number of mature G. abietina pycnidia on shoots formed in the years 1989–1991 suggests that the epidemic will continue in the near future.
Modelling rubber‐tree root diseases, simulations of various inoculum rates and methods of control
Authors: Nandris D. , Chadoeuf J. , Pierrat J. C. , Joannes H. , Geiger J. P. , Nicole M. 
Published: June 2007

SummaryTwo root‐rot fungi,Rigidoporus lignosusandPhellinus noxiusare the causal agents of severe damage in Ivory Coast rubber tree (Hevea brasiliensis) plantations. Mathematical investigations were made using data from a previous 6 year long epidemiological survey. Modelling of spatial spread of the pathogens and mortality of the infected trees, lead to simulations of the quantitative evolution vs. time of root diseases. The theoretical kinetics obtained revealed intra‐ and interspecific variability among the studied stands with respect to the damage caused. Using this model, different phytosanitary scenarios were simulated in relation to the density of the initial inoculum, the control measures, the specificity of the fungicide, the efficiency of the treatment, and the optimal time for application. Their influence on root‐disease dynamics was quantified. The characteristics of the model, its applicability in plantations and its use in predicting disease or stand development are discussed.
RAPD variation in Gremmeniella abietina attacking Pinus sylvestris and Pinus contorta in northern Sweden
Authors: Hansson P. , Wang X‐R. , Szmidt A. E. , Karlman M. 
Published: June 2007

SummaryGenomic DNA from 81 isolates of Gremmeniella abietina collected from eleven plantations each of Pinus sylvestris and Pinus contorta in northern Sweden was studied using RAPD markers. The DNA variation between and within populations and the race and type distribution of G. abietina populations, causing symptoms similar to those of the North American race, were studied. The degree of genetic similarity was greater among G. abietina isolates from the same geographical areas than among isolates from different geographical areas, regardless of whether they were isolated from P. sylvestris or P. contorta. RAPD variation was greatest in the central parts of northern Sweden, suggesting that sexual reproduction has been somewhat more important there than further north or south. Only the RAPD fragments characteristic of the EU race of G. abietina were found in the material tested. The RAPD pattern described as characteristic of the northern type within the EU race was identified in 62% of the isolates. Divergence from the expected profile was due to differences in occurrence of fragments OPA12‐1400 and 12‐1500. This indicates that this part of the RAPD profile cannot be treated as diagnostic for the northern type. A conclusion of practical importance is that there is a considerable risk of G. abietina spreading from infected P. contorta plantations to adjacent areas with indigenous P. sylvestris regeneration, and vice versa, owing to the indicated lack of host‐specificity of the pathogen. It is possible, however, that host‐specific strains exist, but do not differ in their RAPD profiles.
Detection of genetic variation between Ophiostoma ulmi and the NAN and EAN races of O. novo‐ulmi in Switzerland using RAPD markers
Authors: Hoegger P. J. , Binz T. , Heiniger U. 
Published: June 2007

SummaryThe structure of the Ophiostoma ulmi and Ophiostoma novo‐ulmi population of Switzerland was analysed. 79 Swiss isolates were compared to reference strains from various countries. A dendrogram from RAPD profiles was produced. O. ulmi and O. novo‐ulmi were clearly separated into two major clusters. O. novo‐ulmi was further divided into the EAN and NAN races. This classification is consistent with subgroups by taxonomic parameters (growth rate, culture aspect, fertility barriers). The variation detected within the EAN and NAN races indicates a post‐epidemic situation in Switzerland. A clonal population is present only in a restricted area in mid‐eastern Switzerland, indicating a still active disease front.
Stem lesions on Betula pendula seedlings in Finnish forest nurseries and the pathogenicity of Phytophthora cactorum
Authors: Lilja A. , Rikala R. , Hietala A. , Heinonen R. 
Published: June 2007

Summary Phytophthora cactorum was isolated from necrotic stem lesions on 20–80% of diseased Betula pendula seedlings sampled from three nurseries in Finland. Fusarium avenaceum and Godronia sp. were also found in all nurseries. Inoculation of P. cactorum on B. pendula seedlings caused necrotic lesions and the spread of these lesions around the stem was detrimental. Neither the timing of N application nor two different PK‐levels applied to the seedlings the previous year significantly affected the size of lesions caused by P. cactorum.
Identification of multiple Endocronartium pini infections in Scots pine with PCR
Authors: Pappinen A. , Kasanen R. , Weissenberg K. 
Published: June 2007

SummaryRust susceptibility in pine is known to be heritable, which means that the disease risk remains in a stand. Also, if the climate becomes warmer and more humid, as expected, the risk of rust disease will increase. The main trait of interest and importance in an obligate parasite, such as Endocronartium pini is the variation in pathogenicity. However, to test the variation in pathogenicity the fungal population in a stand must be described. In this study it was possible to partly describe an E. pini population at stand level with RAPD‐PCR and identify multiple infections in a single infected tree (Pinus sylvestris). Some RAPD phenotypes detected were more common than others. This suggests some mechanism by which some phenotypes spread more effectively. The E. pini population structures in the two Pinus sylvestris stands studied were also significantly different, even when the stands shared some equally common RAPD phenotypes. The most common phenotype was not always present in a tree with multiple infections, as would be expected. Thus, some specific resistance interaction may occur. Further research is needed to prove this assumption.
The spreading of the S type of Heterobasidion annosum from Norway spruce stumps to the subsequent tree stand
Authors: Piri Tuula 
Published: June 2007

SummaryThe occurrence of Heterobasidion annosum in stumps and growing trees was investigated on 15 forest sites in southern Finland where the previous tree stand had been Norway spruce (Picea abies) infected by H. annosum, and the present stand was either Scots pine (Pinus sylvestris), lodgepole pine (Pinus contorta), Siberian larch (Larix siberica), silver birch (Betula pendula) or Norway spruce 8–53 years old. Out of 712 spruce stumps investigated of the previous tree stand, 26.3% were infected by the S group and 0.3% by the P group of H. annosum. The fungus was alive and the fruit bodies were active even in stumps cut 46 years ago. In the subsequent stand, the proportion of trees with root rot increased in spruce stands and decreased in stands of other tree species. On average, one S type genet spreading from an old spruce stump had infected 3.0 trees in the following spruce stand, 0.5 trees in lodgepole pine, 0.3 trees in Siberian larch, 0.05 trees in Scots pine and 0.03 trees in silver birch stand. Although silver birch generally was highly resistant to the S type of H. annosum, infected trees were found on one site that was planted with birch of a very northern provenance.
Pathogenitätstests mit Bursaphelenchus mucronatus an Kiefern und Fichtensämlingen in Deutschland
Authors: Braasch Von H. 
Published: June 2007

Summary Pathogenicity tests with Bursaphelenchus mucronatus on pine and spruce seedlings in Germany Inoculation tests on Pinus sylvestris seedlings with a German, a Siberian and a French isolate of Bursaphelenchus mucronatus and on Picea abies seedlings using only the German isolate have clearly shown, under German field conditions, that the nematode can cause wilt symptoms on the apex of about 60% of the inoculated P. sylvestris plants. The nematodes in all these tests mostly remained near the inoculation site. However, further spread of the nematodes and wilt symptoms occured when a climate chamber, at 25°C, was used or when the French isolate was used outdoors. At 25°C, 10% of the inoculated plants with at least 1000 nematodes per seedling died. Seedlings' apices wilted if more than 50 nematodes per trunk were present, whereas smaller numbers of nematodes could cause partial wilting. Nevertheless, a few pine seedlings did tolerate high nematode‐population densities, up to 966 per plant. No further progress of wilt of plants with symptoms was observed the following year. Inoculations of P. abies with a German isolate resulted in population development near the site of inoculation. Spruces largely tolerated nematode infestations without any development of wilt symptoms.
Weevil feeding on Scots pine affects germination of Endocronartium pini
Authors: Pappinen A. , Weissenberg K. 
Published: June 2007

SummaryThe aim of this study was to assess the effect and importance of the feeding of the pine top weevil (Pissodes piniphilus) on the germination of Endocronartium pini (syn. Peridermium pini) in Scots pine (Pinus sylvestris), and thus to establish the possibility of the E. pini infection via insect woundings. Germination tests were therefore carried out on current and previous year needle and phloem extracts. Elucidation of the importance of pathogen infection for the insect's feeding preference was also required; for this purpose feeding preference tests were carried out with healthy and infected pine branches using the pine top weevil as a test insect. Weevil feeding increased the germination of E. pini aeciospores on pine extracts. Germination on previous year annual‐shoot extracts was lower than that on current year annual‐shoot extracts. The advance of the growing season increased this trend, but weevil feeding increased germination on extracts from older annual shoots to the levels found on extracts from current annual shoots. Spores germinated equally well on needle extracts and on phloem extracts. The weevils ate more often on infected branches than on healthy branches. E. pini infections may occur via woundings on branches and weevil feeding may facilitate this.
Sexual behaviour of Armillaria heimii and A. mellea isolates from Africa
Authors: Abomo‐Ndongo S. , Mohammed C. , Guillaumin J.‐J. 
Published: June 2007

SummaryThirty isolates ofArmillaria heimiifrom western, eastern and southern Africa were cultured for fruit body production in the laboratory. Most isolates fruited easily. Investigation of single‐spore progenies revealed that all the isolates do not have the same sexual behaviour: some are heterothallic and unifactorial while others are homothallic. Two African isolates belonging to the speciesArmillaria melleaalso appeared homothallic. Unifactorial heterothallism has not previously been described inArmillaria, species. Homothallic behaviour has been reported only in a rare European speciesArmillaria ectypaand in the Japanese subspeciesArmillaria melleassp.nipponica.
Variability of virulence of Nectria galligena towards northern hardwoods
Authors: Plante F. , Bernier L. 
Published: June 2007

SummaryThe variability of virulence within a Québec population of the fungal pathogen Nectria galligena was studied under greenhouse conditions. Preliminary, small‐scale inoculation of Betula alleghaniensis saplings confirmed that wounds have to be present for successful infection by N. galligena and showed that saplings held at 10°C exhibited a broader range in necrotic zone length than saplings held at 24 °C for 6 weeks. Results from the inoculation of B. alleghaniensis saplings with eight full‐sib progeny sets of four siblings each of N. galligena showed a wide range of virulence in this pathogen. The observed variability was probably of genetic origin since, in seven cases out of eight, one of the four siblings of a given family was significantly different from at least one other sibling of the same family. Inoculation of B. alleghaniensis saplings with a population of 43 isolates originating from different host species and geographical locations further confirmed the variability of virulence within N. galligena but failed to indicate a relationship between virulence and host or geographic provenance. Inoculation of six additional deciduous tree species with a subset of nine isolates showed the polyphagous character of the pathogen, as lesions of comparable length were generally observed on five of the species tested. None of the nine isolates tested induced any necrosis on Fraxinus americana whereas Quercus macrocarpa tended to be slightly more resistant than the four remaining true species.
Pathogenicity of A and B morphotypes of Sphaeropsis sapinea confirmed on American larch (tamarack) and European larch
Authors: Stanosz G. R. , Smith D. R. , Guthmiller M. A. 
Published: June 2007

SummaryFungi identified as Sphaeropsis sapinea (or synonyms) have been reported from Larix. Lack of pathogenicity tests, confusion about the identity of isolates mentioned in previous literature, and existence of distinct populations (A and B morphotypes) of the pathogen indicated the need to evaluate the ability of S. sapinea to cause disease of larch. Elongating snoot tips of Larix decidua, Larix laricina, and known hosts of the pathogen, Pinus banksiana and Pinus resinosa, were inoculated with water‐agar plugs colonized with an A or a B isolate, or sterile plugs (controls). Each of five replications included five seedlings for each treatment‐species combination. After 6 weeks, no symptoms had developed on control seedlings, but two‐way analyses of variance revealed significant effects of isolate morpnotype and host on both incidence and severity of disease (values of p ≤ 0.01). The A isolate killed almost all shoot tips, but the B isolate killed from no P. resinosa shoots to 56% of L. laricina shoots. The average length of shoot killed by the A isolate was also greater than that killed by the B isolate. Response to the B isolate again varied among species, with greater average lengths of shoot killed on the larches (compared with the pines). Both A and B morphotypes of 5. sapinea should be considered among the fungi encountered on L. decidua and L. laricina.