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1.
The distribution of Armillaria species was investigated in Serbian forest ecosystems, in relation to the main host species attacked, forest‐types, geography and altitude. In total, 388 isolates were identified from 36 host species in 47 sites. Armillaria gallica was the most commonly observed species with the widest distribution and with an altitudinal range of 70–1450 m, it was the dominating Armillaria species in lowland alluvial forests and in Quercus and Fagus forests at higher elevations. Armillaria mellea occurred in Quercus spp. – dominated forests in the north and central regions at 70–1050 m. Sixty‐eight per cent of the A. mellea isolates were collected from living hosts, most commonly in declining conifer plantations. Armillaria ostoyae was distributed in the cooler coniferous forest types and plantations in the Dinaric Alps in the south of Serbia, at 850–1820 m. Armillaria cepistipes was found in the eastern and southern hilly and mountainous regions of the country, at 600–1900 m. Most isolates were obtained from conifers and rhizomorphs in the soil around decaying stumps. Armillaria tabescens was found only on dead oak material in the northern and eastern regions of the country at altitudes lower than 600 m. 相似文献
2.
Forests in the Ozark Mountains of northern Arkansas recently experienced a widespread oak decline event. Armillaria, a root rot fungus, has been associated with other oak decline events and may have been an important contributing factor to tree mortality in this event. Although Armillaria has been identified from the Ozark Mountains in Missouri, it has never been investigated in the Arkansas Ozarks. Molecular diagnostic techniques were used in this study to identify species of Armillaria present on roots removed from dead trees of two common oak species, northern red oak, Quercus rubra L., and white oak, Q. alba L., from three geographic areas and on three topographic positions – ridges, south‐ and west‐facing benches. Armillaria(A. mellea, A. gallica or A. tabescens) was identified from 31% of root samples taken from 102 trees in seven of nine sample plots. Armillaria mellea, occurred most often (20 samples, both oak species on seven plots) followed by A. gallica (10 samples, northern red oak only on four plots), and A. tabescens occurred twice (on northern red oak in a single plot). Thus, all three Armillaria species occurred on northern red oaks while A. mellea was the only species recovered from white oaks. Results varied by topographic position with samples from tree roots on ridges having the fewest positive identifications, one of 29. West‐facing benches had the highest positive samples with 20 of 41 testing positive and trees on south‐facing benches were intermediate with 11 of 32 samples from infected trees. This study documents the occurrence of three species of Armillaria in the Arkansas Ozarks and their association with oak mortality resulting from an oak decline event coupled with a red oak borer, Enaphalodes rufulus, outbreak. Further, it documents some potential variation in host/pathogen combinations and forest site conditions. 相似文献
3.
Armillaria ostoyae, Perenniporia subacida, Resinicium bicolor and Scytinostroma galactinum, root and butt rot fungi found on red spruce, Picea rubens, were tested, in vitro, for their sensitivity to metals typically found in high elevation forest soils where red spruce grows. Rhizomorph production by A. ostoyae from woody inocula in soils from red spruce stands at three elevations at each of five mountainous sites in the eastern United States was inhibited completely in the mineral soil from all elevations at all sites, and was also reduced significantly in the organic horizon from the upper two elevations at three of the sites. Inhibition was correlated with concentrations of metal ions in the soil. Growth of rhizomorphs into an agar medium containing lead and other heavy metals was inhibited for isolates of A. ostoyae from red spruce, but not for an isolate of Armillaria gallica from sugar maple; aluminium inhibited rhizomorph growth of isolates of both species. Mycelial growth of all four root and butt rot fungi was inhibited by lead, aluminium and other heavy metals depending on the solubility and concentration of metal and pH of the medium; growth inhibition was usually greater at an initial pH of 3.5 than at pH 4.5. Metal ions inhibited radial growth of Armillaria species more than that of the other three fungi. Rhizomorph growth of Armillaria was inhibited more than radial growth. Because local spread of A. ostoyae occurs frequently by means of rhizomorph growth between near roots, increases in lead, aluminium and other metals in the forest floor may contribute to this fungus' scarcity in high elevation soils and reduced incidence of infection at these sites in the eastern United States. 相似文献
4.
Brandon C. Alveshere Shawn McMurtrey Patrick Bennett Mee‐Sook Kim John W. Hanna Ned B. Klopfenstein James T. Blodgett Jared M. LeBoldus 《Forest Pathology》2021,51(1):e12663
Root disease pathogens, including Armillaria, are a leading cause of growth loss and tree mortality in forest ecosystems of North America. Armillaria spp. have a wide host range and can cause significant reductions in tree growth that may lead to mortality. DNA sequence comparisons and phylogenetic studies have allowed a better understanding of Armillaria spp. taxonomic diversity. Genetic sequencing has facilitated the mapping of species distributions and host associations, providing insights into Armillaria ecology. These studies can help to inform forest management and are essential in the development of disease risk maps, leading to more effective management strategies for Armillaria root disease. Armillaria surveys were conducted on publicly owned lands in North Dakota, South Dakota, and Nebraska, U.S.A. Surveyed stands consisted of riparian forests ≥0.4 hectares in area. Armillaria was found at 78 of 101 sites. A total of 57 Armillaria isolates—associated with 12 host tree species—were used for DNA sequencing of the translation elongation factor‐1 alpha (tef1) gene. Armillaria gallica was the only species identified within the study sites. Results suggest that A. gallica is a common root pathogen of hardwood trees in riparian forests of the northern Great Plains with a wider host range and geographic distribution than previously recognized. 相似文献
5.
Armillaria causes problems of root rot, kill trees and decay wood in the forests of Serbia and Montenegro, but the species involved have not hitherto been identified. The aim of this study was to identify field isolates collected on 25 localities. Identification was based on restriction fragment length polymorphism (RFLP) analysis of intergenic spacer 1 (IGS1) region and comparisons of IGS1 sequence with those available on NCBI database. Phylogenetic analysis was performed on sequence information from selected isolates to determine possible interrelationships between isolates with different banding patterns and previously identified tester isolates of five European Armillaria species. Five Armillaria species were identified in 90 isolates obtained from forests in Serbia and Montenegro. Armillaria gallica was most frequently isolated, followed by A. cepistipes, A. mellea, A. ostoyae and A. tabescens; two isolates remained unidentified. Restriction digestion of IGS1 amplification products with AluI produced 10 RFLP patterns. Patterns G4 (400, 250, 180) for A. gallica and pattern X (400, 180, 140) for isolates 74 and 79 are reported for the first time in European isolates. Eight RFLP patterns were observed after restriction with TaqI. Two patterns each were observed for A. ostoyae and A. gallica, and one each for A. cepistipes, A. mellea, A. tabescens and isolates 74 and 79. Parsimony analyses based on the IGS1 region placed the isolates into four clades: one including A. mellea, the second containing A. gallica–A. cepistipes isolates, while isolates of A. ostoyae and A. borealis were in the third clade. Armillaria tabescens differed from all annulate species. Phylogenetic analysis supported the conclusion that European Armillaria species are closely related and separated from a common ancestor in the near past. According to this survey five European Armillaria species are present in the forests of Serbia and Montenegro, while A. borealis is not present in the studied ecosystems. 相似文献
6.
Species of Armillaria were identified from 645 isolates obtained in a nation‐wide survey in Albania. The material was collected from ca. 250 permanent plots, established for monitoring forest health, and from forests and orchards attacked by Armillaria. Armillaria mellea s.s. occurred on several coniferous and broadleaved trees in most areas examined, although it was absent above 1100–1200 m in northern Albania. This species damaged Abies and Quercus spp. and, to a lesser extent, other forest trees. Armillaria mellea was also commonly recorded causing damage in orchards and vineyards. Armillaria gallica was a common saprophyte or weak pathogen in coniferous and deciduous forests at altitudes from 600 to 1600 m, and less commonly on oaks at lower altitudes. Armillaria ostoyae was rare in central and southern Albania, but common in northern Albania, causing significant damage to pine and other conifers, mostly at altitudes from 600 to 1800 m. Armillaria cepistipes was recorded at altitudes from 800 to 1800 m as a saprophyte or weak pathogen on conifers and deciduous trees, mostly in beech and silver fir forests. Armillaria tabescens was found in oak forests at altitudes from sea level to 900 m. In orchards, A. tabescens occasionally attacked almond and pear trees. Armillaria borealis was found in a few locations in northern Albania, at altitudes from 800 to 1800 m. 相似文献
7.
J. N. Bruhn J. J. Wetteroff J. D. Mihail J. M. Kabrick J. B. Pickens 《Forest Pathology》2000,30(1):43-60
Armillaria root disease is a contributing factor to oak decline in the Ozark Mountains of central USA. We have identified Armillaria gallica, Armillaria mellea, and Armillaria tabescens in Quercus‐Carya‐Pinus forests of the region. Presence/absence patterns of each Armillaria species as well as all possible Armillaria species combinations were analysed by contingency tables and/or stepwise logistic multiple regressions with principal characteristics of the studied sites and forest stands, both quantitative and qualitative: geographic land‐type association, bedrock type, landform position, slope direction (aspect), soil type and soil surface stone cover, down woody debris, abundance and basal area of woody vegetation and decline mortality by species. Most decline mortality consisted of two red oak species (section Erythrobalanus, Quercus coccinea and Quercus velutina), which also were most sensitive to Armillaria infection. Site characteristics related to the distributions of Armillaria species and decline mortality were also related to the preponderance of Q. coccinea and Q. velutina, regional vegetation history (i.e. conversion of Pinus echinata stands to hardwoods), and the different strategies of territory acquisition and spread of the Armillaria species involved. The presence of A. gallica may reduce the activity of more virulent Armillaria species. 相似文献
8.
Symptoms and signs associated with root rot caused by Heterobasidion annosum or Armillaria ostoyae in mountain pines (Pinus mugo ssp. uncinata) were investigated in the Swiss Alps. A sample of dying or recently dead mountain pine trees (≥12 cm d.b.h.) and saplings (<1.3 m height) was assessed for root pathogen infection by taking root samples followed by isolations in the laboratory. From a subsample, an additional core was taken from the butt of each tree and evaluated in the same fashion. A total of 157 dying or recently dead mountain pine trees and 184 saplings with roots infected by either of the two pathogens or which lacked infection were analyzed using logistic regression models. The main objectives were to determine the most prominent symptoms induced by the fungi (resinosis), signs of the fungi (mycelia, fruiting bodies and rhizomorphs), and tree characteristics (d.b.h./height and evidence of wounds) that would allow an easy and reliable determination of H. annosum and/or A. ostoyae infection of mountain pines in the field. Heterobasidion annosum caused both root and butt rot on mountain pine, whereas A. ostoyae was mostly restricted to the root systems of the trees sampled. The most discriminating sign for the presence of A. ostoyae infection was the presence of characteristic mycelial fans, and for H. annosum root rot the presence of H. annosum mycelia (sheets of paper‐thin mycelium and mycelial pustules). In addition, resinosis was a powerful predictor for A. ostoyae in trees. Symptoms and signs indicating A. ostoyae or H. annosum infections were more reliable for saplings than for mature trees. Armillaria rhizomorphs were not useful in detecting A. ostoyae infection and, if present, were often formed by saprophytic Armillaria species. Heterobasidion annosum fruiting bodies were rarely observed and poorly reflected the widespread occurrence of this pathogen in the mountain pine forests. 相似文献
9.
Armillaria species from Japan were characterized using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) of the intergenic spacer region-1 (IGS-1) of ribosomal DNA (rDNA). Eleven different digestion patterns by restriction endonuclease Alu I were found among 70 isolates of seven Armillaria species in Japan. Isolates within Armillaria nabsnona, A. ostoyae, A. cepistipes, and Japanese biological species E showed the same Alu I digestion patterns. Five Alu I patterns were detected for A. gallica, three patterns for A. mellea, and two patterns for A. tabescens. Seven Armillaria species in Japan were clearly distinguished by using the profiles obtained when PCR products were digested with Alu I, Msp I, and Hae III restriction enzymes. There was considerable variability of Alu I restriction sites within the IGS-1 between the isolates of five Armillaria species, A. gallica, A. nabsnona, A. cepistipes, A. mellea, and A. tabescens, in Japan and those of their European and North American counterparts. 相似文献
10.
The occurence of Armillaria species was assessed in Norway, enabling the northern‐most distribution of this genus to be determined in Europe. Four Armillaria species were found in Norway. Armillaria borealis was the most common species occurring on woody vegetation to the permafrost zone (ca. 69°N). Armillaria cepistipes was present in southern and central Norway, but was not found further than 66°N. Armillaria solidipes and Armillaria gallica were rare, found at only one locality each; 59°40′ and 59°32′, respectively. Armillaria species were found on 14 hosts, but there was no significant difference between occurrence of A. borealis and A. cepistipes on declining and dead trees. Phylogenetic analyses separated each species into separate clades. All isolates of A. borealis, except one, and most isolates of A. solidipes were in separate clades. However, a subclade within the A. borealis clade was formed of two A. ostoyae and one A. borealis isolates. Two small A. cepistipes genets were found in a declining oak stand. 相似文献
11.
Phylogenetic and genetic relationships among 10 North American Armillaria species were analysed using sequence data from ribosomal DNA (rDNA), including intergenic spacer (IGS‐1), internal transcribed spacers with associated 5.8S (ITS + 5.8S), and nuclear large subunit rDNA (nLSU), and amplified fragment length polymorphism (AFLP) markers. Based on rDNA sequence data, the nLSU region is less variable among Armillaria species than the ITS + 5.8S and IGS‐1 regions (nLSU < ITS + 5.8S < IGS‐1). Phylogenetic analyses of the rDNA sequences suggested Armillaria mellea, A. tabescens and A. nabsnona are well separated from the remaining Armillaria species (A. ostoyae, A. gemina, A. calvescens, A. sinapina, A. gallica, NABS X and A. cepistipes). Several Armillaria species (A. calvescens, A. sinapina, A. gallica, NABS X and A. cepistipes) clustered together based on rDNA sequencing data. Based on the isolates used in this study, it appears that techniques based on IGS‐1, ITS + 5.8S, and/or D‐domain/3′ ends of nLSU are not reliable for distinguishing A. calvescens, A. sinapina, A. gallica and A. cepistipes. However, AFLP data provided delineation among these species, and AFLP analysis supported taxonomic classification established by conventional methods (morphology and interfertility tests). Our results indicate that AFLP genetic markers offer potential for distinguishing currently recognized North American Biological Species (NABS) of Armillaria in future biological, ecological and taxonomic studies. 相似文献
12.
The geographical distribution of the annulate Armillaria species was studied in The Netherlands during the period 1983–1992. Armillaria gallica (incl. A. cepistipes), A. mellea and A. ostoyae appear to be widespread, the first two species being rather common on broad-leaved hosts growing on clay and loess soils, and the third species common on both broad-leaved and coniferous hosts on acid sandy soils. The distribution of the Armillaria species encountered was primarily determined by soil type. From a silvicultural point of view, A. ostoyae is the most important species, being pathogenic and occurring most frequently on sandy soils, the soil type predominantly used for forestry in The Netherlands. 相似文献
13.
P. Tsopelas 《Forest Pathology》1999,29(2):103-116
Five Armillaria species were identified in a nationwide survey in Greece. Armillaria mellea was present in coniferous and broad-leaved forests in most of the areas examined, except the high altitudes (above 1100 m) of the mountains of north Greece. It was found to cause significant damage in fir forests as well as in fruit orchards and vineyards. Armillaria gallica was common in coniferous and broad-leaved forests in the high altitudes of central and northern Greece, predominating in the beech forests. The fungus was a weak parasite or a saprophyte of forest trees and was occasionally found on cultivated plants. Armillaria ostoyae was not found in southern and central parts of the country, but it has a wide distribution in the mountain forests of northern Greece and causes significant damage on fir, black pine, Scots pine and spruce. Armillaria cepistipes was recorded at high altitudes (1400–1800 m) on two mountains of northern Greece, mostly as a saprophyte in coniferous and broad-leaved forests. Armillaria tabescens was rare in the forests of Greece; it was found to cause disease in almond tree orchards. 相似文献
14.
The intersterility groups of 127 pure cultures of H, annosum collected from different host trees in 12 mountain areas in Greece were identified. The F group commonly caused butt rot on the fir species Abies cephalonica and Abies borisii regis. It was the only type of H. annosum found in pure fir forests. The P group caused serious root rot in pinus sylvestris stands in north-eastern Greece. In more southern mountain areas it often colonized stumps of pinus nigra but seldom killed this tree species. The S group was found in natural forests of Picea abies in northern Greece, causing butt rot of spruce. In mixed forests, the intersterility groups of H. annosum were found relatively often in stumps of tree species other than their main hosts, although some host preference seemed to occur also in stump colonization. 相似文献
15.
16.
To 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. 相似文献
17.
The basidiomycetes Armillaria cepistipes and Armillaria ostoyae frequently occur in the same forest stand. In this study, we determined the virulence of 20 isolates of A. cepistipes and 16 isolates of A. ostoyae on four different provenances of 2‐year‐old Norway spruce (Picea abies). Within 30 months after inoculation, 1.1 and 19.1% of the seedlings inoculated with A. cepistipes and A. ostoyae, respectively, had died or were dying. The incidence of dead and dying seedlings varied between 3 and 49% among the A. ostoyae isolates. The virulence of an isolate was positively correlated to its ability to produce rhizomorphs. One Norway spruce provenance showed significantly lower susceptibility to A. ostoyae than the other three. Rhizomorphs of both Armillaria species were attached to the root surface. The attached rhizomorphs of A. ostoyae, however, were associated with significantly more lesions. The virulence of the isolates was not correlated with their wood‐degrading capability for either of the Armillaria species. 相似文献
18.
Initial characterization of an unidentified Armillaria isolate from Serbia using LSU‐IGS1 and TEF‐1‐α genes 
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下载免费PDF全文 Armillaria species have a global distribution and play variable ecological roles, including causing root disease of diverse forest, ornamental and horticultural trees. Accurate identification of Armillaria species is critical to understand their distribution and ecological roles. This work focused on characterizing an unidentified Armillaria isolate from a Serbian forest using pairing, sequencing of the partial large subunit and intergenic spacer‐1 regions of rDNA (LSU‐IGS1) and the translation elongation factor‐1 alpha gene (tef‐1α) genes, and phylogenetic analyses. Despite previously obtained LSU‐IGS1 RFLP patterns that matched the newly described North American Armillaria altimontana, pairing tests and phylogenetic analyses of LSU‐IGS1 and tef‐1α sequences clearly demonstrate that the unidentified isolate is not A. altimontana. Based on LSU‐IGS1, Armillaria gallica isolates were polyphyletic, and the Serbian isolate clustered with a subset of European A. gallica isolates within a well‐supported clade (99%). Based on tef‐1α, the Serbian isolate appeared as a separate, well‐supported clade (97%) that was basal to other poorly resolved, polyphyletic clades containing European A. gallica isolates. It is speculated that the unidentified Armillaria isolate from Serbia could represent an evolutionary ancestral state because of its separate, basal position compared with other clades comprising polyphyletic European A. gallica isolates. Alternatively, this unidentified Serbian isolate could represent an unusual hybrid because of its high‐level sequence heterogeneity, represented by multiple two‐nucleotide codes, within tef‐1α. Further characterization is needed to confirm the taxonomic status and ecological/evolutionary significance of this unique, unknown Armillaria isolate from Serbia. 相似文献
19.
A. Lehtijärvi H. T. Doğmuş‐Lehtijärvi A. G. Aday Kaya S. Ünal S. Woodward 《Forest Pathology》2017,47(6)
Although several Armillaria species have been reported in Turkey, there is little information about their ecology in Turkish forests. In this study, we investigated five forest stands, approximately 5–74 ha in size, in Kastamonu province in the Black Sea Region of Turkey for the presence of Armillaria species in stumps and logs. The stands were mixed Abies nordmanniana ssp. bornmülleriana and Pinus sylvestris forests managed using a selective cuttings system; the proportion of fir in the total number of stems and stumps ranged from 36 to 98%. Based on sequence analysis of the internal transcribed spacer and intergenic spacer regions of the rDNA, all rhizomorphs sampled from the stumps and logs were of Armillaria ostoyae. The size of the genets was estimated with random amplified microsatellites analysis of the isolates and ranged from single stumps to approximately 450 m2. One to seven genets were found in each stand. These results indicate that the genets had arisen from spores and vegetative spread was limited on most sites. 相似文献
20.
Attempts to design species‐specific PCR primers from six European Armillaria species in the ribosomal RNA genes are reported. Primers were developed on the basis of the nucleotide sequence variability of the internal transcribed spacers (ITS) and the intergenic spacer (IGS1) of the ribosomal DNA. Four sets of primers gave specific PCR products for Armillaria tabescens, Armillaria mellea and Armillaria ostoyae. However, due to the high sequence similarities between Armillaria borealis and Armillaria ostoyae and between Armillaria cepistipes and Armillaria gallica no species specific amplification was obtained for these taxa. 相似文献