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1.
2.
The lichen flora on 400 Picea abies trees (branches, trunks and trunk bases) in 100 patches of suboceanic spruce forest in Central Norway has been investigated. Relationships between occurrence of the species and a number of habitat and tree variables were analysed by detrended correspondence analysis (DCA). A total of 122 lichen species were recorded. Total species number was found to be about the same on branches and trunk bases (considerably lower on trunks), but with higher β-diversity on trunk bases. Most species could be classified as branch specialists, generalists, trunk or trunk base specialists. Among the measured habitat variables, stand age, altitude and vegetation type were found to be the most important for explaining the patterns of species distributions. Alectoria sarmentosa, Mycoblastus sanguinarius and several dry bark species on trunks, including Caliciales species, were more or less confined to old forests, while Usnea spp. were more abundant in young form. Trentepohlia-containing trunk base species like Arthonia vinosa, Dimerella pineti, Lecanactis abietina and Sclerophora coniophaea showed preference for vegetation types indicating nutrient-rich substrates. The number of branch species was highest on lower altitudes while the opposite was true for trunk species. Larger trees with rough bark in older stands had a more species-rich lichen flora, probably because of higher substratum area and availability of more diverse microsites.  相似文献   

3.
Thirty-three collections of Leotia were used to investigate inter-and infra-specific relationships in the genus. Collections were obtained from various parts of the world and represent the ascomatal color forms typical in species of the genus. The ITS rDNA and a variable region of the RNA polymerase II (RPB2) gene were sequenced and analyzed using parsimony and maximum likelihood methods. Although ITS and RPB2 tree topologies differed in regard to the position of two clades of L. lubrica and L. atrovirens, no significant conflict between ITS and RPB2 data or trees was found as determined by the partition homogeneity test. RPB2 sequences in general gave results comparable to ITS; the RPB2 sequences were more easily aligned. Phylogenetic analysis of the sequence data indicates that L. viscosa, L. lubrica and L. atrovirens are polyphyletic species. This suggests that ascomatal color in fresh specimens is not a reliable character alone for determining species in this group. Four major well-supported groups were found; these do not fully correspond to the commonly recognized species. Stipe color, in both fresh and dry condition, seems to correlate with the major recognized groups but features of the ascospores, asci and paraphyses prove too variable to be informative. The most basal group of Leotia species, identified as L. atrovirens, differ from all others by having stipes without gel tissue in their outer layers.  相似文献   

4.
Abstract Trunk‐associated invertebrates were sampled on marri trees (Eucalyptus (Corymbia) calophylla) along a transect from Karragullen, near Perth, through to Dryandra, 150 km to the south‐east. This represents a drop in annual rainfall from 1078 to 504 mm, which is accompanied by a change from jarrah (Eucalyptus marginata) forest to wandoo (Eucalyptus wandoo) woodland. Invertebrates were sampled by intercept traps, which collect invertebrates that attempt to land on the trunks, and bark traps, which collect invertebrates that move, or live, on the trunk. Trends are reported here at the ordinal level. The variety and abundance of invertebrates sampled was generally greater in the intercept than the bark traps. Invertebrate abundance, activity and biomass on bark were strongly seasonal, with greater numbers being found during the moister periods. Invertebrate abundances tended to be greater at the drier, eastern end of the transect, particularly on the three sites within wandoo woodland. These trends were analysed in terms of rainfall, soil nutrients and plant community composition. The analysis failed to detect an underlying influence of any of these factors, suggesting that the observed trends on marri trunks may be the result of invertebrate responses to the dominant tree species at the western and eastern ends of the transect, namely jarrah and wandoo respectively.  相似文献   

5.
Proto‐Araceae, the earliest diverged lineage within the family Araceae, includes two subfamilies, Gymnostachydoideae (one species) and Orontioideae (eight species). Based on an extensive sampling (a total of 198 accessions) of six chloroplast non‐coding regions (5799 aligned sites), we assessed phylogenetic relationships among the genera and species within subfamily Orontioideae and estimated the timing of intercontinental disjunct events in the Northern Hemisphere. Overall phylogenetic relationships among the genera were consistent with results from previous studies, but several new important findings were discovered, primarily within Symplocarpus Salisb. ex W. P. C. Barton. First, two major lineages within Symplocarpus were identified: one lineage included S. foetidus (L.) Salisb. ex W. Barton, S. nabekuraensis Otsuka & K. Inoue, and S. renifolius Schott ex Tzvelev (Japan), whereas the other included S. nipponicus Makino, S. egorovii N. S. Pavlova & V. A. Nechaev, and S. renifolius (Korea). Symplocarpus renifolius in Japan was tetraploid and closely related to the tetraploid S. foetidus in eastern North America. Populations of S. renifolius in Korea were confirmed to be diploid (2n = 30) and shared the most recent common ancestor with the other diploid species, S. nipponicus. Second, two recently described species, S. nabekuraensis and S. egorovii, were deeply embedded within S. renifolius in Japan and Korea, respectively, and their distinct taxonomic status requires further assessment. Finally, two intercontinental disjunction events in the subfamily, one in Lysichiton Schott between eastern Asia and western North America and the other in Symplocarpus between eastern Asia and eastern North America, were estimated to be between 4.5 and 1.4 million years ago (Pliocene and Pleistocene) and between 1.9 and 0.5 million years ago (Pleistocene), respectively.  相似文献   

6.
The genus Platycerus is a cool temperature zone taxon widely distributed in the Northern Hemisphere. In East Asia, 10, one and 28 species are known in Japan, Korea and China, respectively. Recent studies of Platycerus have revealed the divergence pattern in Japan and South Korea, but that of Chinese Platycerus is unknown. We conducted a phylogenetic and biogeographical study of Platycerus in East Asia, including China, using 68, 87 and 296 sequence data of the nuclear wingless gene, internal transcribed spacer (ITS) region and mitochondrial COI gene, respectively. Although the introgression of mitochondrial genes had been known in Japanese Platycerus, the essential contradiction was not recognized between the phylogenetic trees of nuclear genes and COI in Chinese Platycerus. In the COI tree, the Japanese clade and Asian continental clade diverged around 10.84 million years ago, and four major clades were recognized in the latter. For the shape of the posterolateral corner of the Platycerus pronotum, sharp (S)-type species are distributed in higher latitudinal and lower altitudinal areas than round (R)-type species in the Asian continent. S-type species have evolved from R-type species at least three times in more northerly areas, where the annual amplitude of temperature change is large. The genus Platycerus has been differentiated and speciated by a process unique to South Korea, Japan and China, according to regional topography. Thus, genetic differentiation and speciation in Platycerus are related to latitudinal and altitudinal gradients, as well as the site topographical profile and niche differentiation.  相似文献   

7.
Hemlock woolly adelgid, Adelges tsugae, is an invasive pest of hemlock trees (Tsuga) in eastern North America. We used 14 microsatellites and mitochondrial COI sequences to assess its worldwide genetic structure and reconstruct its colonization history. The resulting information about its life cycle, biogeography and host specialization could help predict invasion by insect herbivores. We identified eight endemic lineages of hemlock adelgids in central China, western China, Ulleung Island (South Korea), western North America, and two each in Taiwan and Japan, with the Japanese lineages specializing on different Tsuga species. Adelgid life cycles varied at local and continental scales with different sexual, obligately asexual and facultatively asexual lineages. Adelgids in western North America exhibited very high microsatellite heterozygosity, which suggests ancient asexuality. The earliest lineages diverged in Asia during Pleistocene glacial periods, as estimated using approximate Bayesian computation. Colonization of western North America was estimated to have occurred prior to the last glacial period by adelgids directly ancestral to those in southern Japan, perhaps carried by birds. The modern invasion from southern Japan to eastern North America caused an extreme genetic bottleneck with just two closely related clones detected throughout the introduced range. Both colonization events to North America involved host shifts to unrelated hemlock species. These results suggest that genetic diversity, host specialization and host phylogeny are not predictive of adelgid invasion. Monitoring non‐native sentinel host trees and focusing on invasion pathways might be more effective methods of preventing invasion than making predictions using species traits or evolutionary history.  相似文献   

8.
Eucalypts are among the most widely planted forest trees in the world, and outside their native Australian range, the main arthropod pests are sap‐sucking insects, defoliators, gall‐making insects and xylophagous beetles. We report on a new association between a polyphagous wood‐boring beetle and Tasmanian blue gum (Eucalyptus globulus Labill.) in Central Portugal. Unidentified wood‐boring insects were found attacking two three‐year‐old E. globulus trees showing signs of decline among otherwise healthy trees in a commercial plantation, in June 2018. Declining trees presented dead twigs and branches, and recently developed epicormic sprouts evident on the trunks. Insects emerging from logs were identified as Ambrosiodmus rubricollis (Eichhoff), a species native to eastern and southern Asia, with the taxonomic identification validated by molecular analysis. To our knowledge, this is the first record of A. rubricollis associated with a eucalypt species worldwide. It is not clear whether the beetles played any significant role on the decline of the trees, but Ambrosiodmus may be potential pests for several tree and shrub species in Europe, as these beetles can transport pathogenic fungi.  相似文献   

9.
Wood  Timothy S. 《Hydrobiologia》2001,445(1-3):51-56
A new freshwater bryozoan species, Plumatella mukaii, is recognized from eastern Asia and western South America. Colonies and statoblasts both bear a resemblance to P. emarginata, and have often been confused with that species, especially in Japanese studies. Floatoblasts and sessoblasts are enclosed within a tough, wrinkled, membrane which resists removal by mechanical means. Floatoblasts are generally smaller than those of P. emarginata, but display unusually high variability in their overall dimensions. The species has been reported from both lentic and lotic habitats. In Asia, the range includes Japan, Korea, China, India and Indonesia. It has most recently also been found at several sites in Chile. The recognition of P. mukaii narrows the previously reported range of P. emarginata and invites a re-inspection of that species worldwide.  相似文献   

10.
Wang Z  Binder M  Dai YC  Hibbett DS 《Mycologia》2004,96(5):1015-1029
Sparassis species show extensive morphological variation, especially when materials from eastern Asia and Australia are compared with collections from North America and Europe. We have been studying the taxonomy of Sparassis from eastern Asia, North America, Australia and Europe, using both morphological and molecular data. DNA was extracted from 32 recent collections of Sparassis from Australia, Canada, China, Finland, France, Germany, Japan, Switzerland, Thailand, the United Kingdom and the United States. The report of a Sparassis taxon from Australia is the first report of this genus from the Southern Hemisphere. Sequences of nuclear and mitochondrial rDNA and the gene encoding RNA polymerase subunit II (RPB2) were used to examine relationships both within the genus Sparassis and between Sparassis species and other members of the polyporoid clade. Equally weighted parsimony analyses and Bayesian analyses were performed using independent datasets and combined datasets of sequences from different regions. Our results suggest that: (i) Polyporoid fungi producing a brown rot may form a clade; (ii) as suggested in a previous study, Sparassis and Phaeolus form a monophyletic group, which is united by the production of a brown rot, the presence of a bipolar mating system and the frequent habit of growing as a root and butt rot on living trees; (iii) at least seven lineages are within Sparassis, represented by S. spathulata, S. brevipes, S. crispa, S. radicata and three taxa that have not been described, which can be distinguished on the basis of fruiting body structure, presence or absence of clamp connections, presence or absence of cystidia and spore size.  相似文献   

11.
1 A field experiment was carried out to test the hypothesis that treatment of Norway spruce trees with the Ips typographus-transmitted blue-stain fungus Ceratocystis polonica enhances tree resistance to later mass attack by this bark beetle. 2 Twenty-five mature trees were pretreated by inoculating a non-lethal dose of the fungus into the bark, while 18 trees served as untreated controls. Three and a half weeks after treatment a bark beetle attack was initiated by attaching dispensers with I. typographus pheromone to the tree trunks. 3 A significantly larger proportion (67%) of the control trees than of the pretreated trees (36%) were killed by the beetle attack. The result is discussed in relation to recent results regarding defence mechanisms in Norway spruce trees.  相似文献   

12.
The biogeographical relationships between far-separated populations, in particular, those in the mainland and islands, remain unclear for widespread species in eastern Asia where the current distribution of plants was greatly influenced by the Quaternary climate. Deciduous Oriental oak (Quercus variabilis) is one of the most widely distributed species in eastern Asia. In this study, leaf material of 528 Q. variabilis trees from 50 populations across the whole distribution (Mainland China, Korea Peninsular as well as Japan, Zhoushan and Taiwan Islands) was collected, and three cpDNA intergenic spacer fragments were sequenced using universal primers. A total of 26 haplotypes were detected, and it showed a weak phylogeographical structure in eastern Asia populations at species level, however, in the central-eastern region of Mainland China, the populations had more haplotypes than those in other regions, with a significant phylogeographical structure (N ST = 0.751> G ST = 0.690, P<0.05). Q. variabilis displayed high interpopulation and low intrapopulation genetic diversity across the distribution range. Both unimodal mismatch distribution and significant negative Fu’s FS indicated a demographic expansion of Q. variabilis populations in East Asia. A fossil calibrated phylogenetic tree showed a rapid speciation during Pleistocene, with a population augment occurred in Middle Pleistocene. Both diversity patterns and ecological niche modelling indicated there could be multiple glacial refugia and possible bottleneck or founder effects occurred in the southern Japan. We dated major spatial expansion of Q. variabilis population in eastern Asia to the last glacial cycle(s), a period with sea-level fluctuations and land bridges in East China Sea as possible dispersal corridors. This study showed that geographical heterogeneity combined with climate and sea-level changes have shaped the genetic structure of this wide-ranging tree species in East Asia.  相似文献   

13.
Recent collections from marine and freshwater locations have enabled the investigation of diversity of Prasiola in Japan. Sequence data from the rbc L and tuf A markers revealed the presence of three marine species and one freshwater species. Prasiola delicata was confirmed to occur on Daikokujima, Prasiola calophylla was found for the first time in Japan from Hokkaido, and a species within the P. meridionalis/linearis/stipitata complex was found on both Hokkaido and Daikokujima. Collections from a range of populations of freshwater Prasiola, identified here as P. japonica, were found to be conspecific and identical in rbc L and tuf A sequences to freshwater collections from Nepal, Korea, and China.  相似文献   

14.
Eucryptorrhynchus brandti (Harold) and E. chinensis (Oliver) are herbivores of Ailanthus altissima (Mill.) Swingle (tree of heaven) in China. Eucryptorrhynchus brandti has been recommended as a potential biological control agent of A. altissima in North America. In China, the majority of adults of both species were found on tree trunks 0–5 m above the ground, from May to September. In October and November, most adults were found at the base of A. altissima trees. Trees were subjected to different levels of mechanical injury: very low mechanical injury, one to two 0.015 m2 bark sections were removed; low, two to four bark sections were removed; moderate, 8 to 22 bark sections removed; high, tree was girdled; and extreme, tree was felled and the remaining stump was sampled. Very low and low mechanical injury trees had very few adult emergence holes with few larvae developing beyond the first or second instar after 29 months. The health of these trees remained good. An increase in adult emergence holes occurred in moderately injured trees that appeared as healthy as very low to low mechanically injured trees. This may indicate that only a small increase in tree stress can increase the adult emergence rate and thus hasten a decline in tree health. Moderate, high and extreme mechanically injured trees had significantly more emergence holes/m than very low and low injured trees and late larval stages were present. The development of Eucryptorrhynchus species was more successful the greater the degree of mechanical injury. Based on this study both Eucryptorrhynchus species appear to be secondary pests of A. altissima in China.  相似文献   

15.
Chloroplast DNA polymorphism in four oak species (Quercus serrata, Q. mongolica var. crispula, Q. dentata and Q. aliena) was studied using collections from a total of 127 localities in Japan and South Korea on the basis of five intergenic spacers (trnD-trnT, trnT-trnL, rps14-psaB, trnS-trnT and trnQ-trnS). Although no variation existed in sequences among the four species, a single nucleotide (T/C) substitution in the trnQ-trnS intergenic spacer was found in all the four species, resulting in two haplotypes (T- and C-type). Phylogenetic analyses of the four species and related species showed that the C-type is derived and even likely of monophyletic origin, while the T-type is ancestral. Geographically, the T-type is widespread from South Korea to Japan, whereas the C-type is restricted to eastern Japan with rare exceptions. Eastern Japan approximately coincides with the distribution range of the boreal conifer forest during the last glacial maximum. Overall evidence suggests that the mutation from T- to C-type occurred in an individual of one of the four oak species and then was transferred to all the species by hybridization in eastern Japan, and that the Kanto District provided individuals with the C-type with a refugium during the last glacial maximum.Electronic Supplementary Material Supplementary material is available in the online version of this article at  相似文献   

16.
Monarch butterflies, Danaus plexippus L. (Lepidoptera: Nymphalidae), occur world‐wide and are specialist herbivores of plants in the milkweed family (Asclepiadaceae). In North America, two monarch populations breed east and west of the continental divide in areas populated by different host plant species. To examine the population variation in monarch responses to different Asclepias species, we measured oviposition preference and larval performance among captive progeny reared from adult butterflies collected in eastern and western North America. Host plant use was evaluated using two milkweed species widely distributed in eastern North America (A. incarnata and A. syriaca), and two species common to western North America (A. fascicularis and A. speciosa). We predicted that exposure to different host plant species in their respective breeding ranges could select for divergent host use traits, so that monarchs should preferentially lay more eggs on, and larvae should perform better on, milkweed species common to their native habitats. Results showed that across all adult female butterflies, oviposition preferences were highest for A. incarnata and lowest for A. fascicularis, but mean preferences did not differ significantly between eastern and western monarch populations. Larvae from both populations experienced the highest survival and growth rates on A. incarnata and A. fascicularis, and we again found no significant interactions between monarch source population and milkweed species. Moreover, the average rank order of larval performance did not correspond directly to mean female oviposition preferences, suggesting that additional factors beyond larval performance influence monarch oviposition behavior. Finally, significant family level variation was observed for both preference and performance responses within populations, suggesting an underlying genetic variation or maternal effects governing these traits.  相似文献   

17.
Old living oaks (Quercus robur) are known as a very species‐rich habitat for saproxylic beetles, but it is less clear to what extent such veteran trees differ from an even rarer feature: downed trunks of large oaks. In this study, we set out to sample this habitat, using window traps, with two aims: (1) to describe the variation of assemblages among downed trunks of different type and (2) to compare beetles on downed oaks with data from veteran standing trees. The results showed that trunk volume and sun exposure better explained assemblages as well as species numbers on downed trunks than did decay stage. Furthermore, species classified as facultative saproxylic species showed weak or no differentiation among downed trunks. Species with different feeding habits showed no apparent differentiation among downed trunks. Furthermore, species composition on dead, downed oak trunks differed sharply from that of living, veteran oaks. Wood or bark feeders were more common on veterans than downed trunks, but there was no difference for those species feeding on fungi or those feeding on insects and their remains. In conclusion, for a successful conservation of the saproxylic beetle fauna it is important to keep downed oak trunks, and particularly large ones, in forest and pastures as they constitute a saproxylic habitat that differs from that of living trees.  相似文献   

18.
When wildlife populations become too large, they impact other flora and fauna within the ecosystems that they inhabit. For example, the recent rise in population numbers of sika deer in Japan has led to the stripping of bark from tree overstories in forested areas. This has led to protective management actions, such as wrapping the trunks of trees in wire mesh. The present study investigates the impact of this management action on epiphytic diversity at Mt. Ohdaigahara, which is one of the hotspots for bryophyte diversity in Japan. The correlation between the diversity of epiphytic bryophytes and environmental variables was examined, including the presence/absence of wire mesh protection. A generalized linear model showed that species richness and bryophyte cover was significantly correlated with both tree diameter (at 1.5 m height) and tree density (P < 0.01), but negatively correlated with wire mesh protection. Inductively coupled plasma-mass spectrometry analysis showed a significant 3- to 6-fold higher concentration of zinc in bryophytes occupying tree bark under wire mesh protection than for those without wire mesh. Hence, the high sensitivity of bryophytes to zinc accumulation, as a result of toxicity caused by galvanized iron mesh, has led to the loss of species richness and bryophyte cover on tree trunks. Furthermore, other heavy metals found in wire mesh may also contribute to the negative effect on bryophytes. Therefore, to establish best practices for biodiversity conservation that include bryophytes, materials that are free of heavy metals should be preferentially used for tree protection.  相似文献   

19.
Wang  Man-Man  Groenewald  Marizeth  Wu  Feng  Guo  Yun-Tong  Wang  Qi-Ming  Boekhout  Teun 《Antonie van Leeuwenhoek》2021,114(5):553-559

The six synonyms currently accepted under Saccharomycodes ludwigii were investigated for by phenotypic properties, however, the sequence diversity of the rRNA and protein coding genes have not yet been determined. Nine strains including the type strains of synonyms of S. ludwigii deposited in the CBS yeast collection, Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands, were analyzed using a multi-locus sequence analysis (MLSA) approach that included sequences of 18S ribosomal RNA (rRNA), the D1/D2 domains of the 26S rRNA, the ITS region (including the 5.8S rRNA) and fragments of genes encoding the largest subunit of the RNA polymerase II (RPB1 and RPB2) and translation elongation factor 1-α (TEF1). Our results showed that the nine strains have identical D1/D2, 18S and RPB2 sequences and similar ITS, RPB1 and TEF1 sequences, which indicated that they are conspecific. In addition, a novel species of Saccharomycodes, S. pseudoludwigii sp. nov. (type CGMCC 2.4526 T) that was isolated from fruit and tree bark in China, is proposed. The MycoBank number of this new species is MB 811,650.

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20.
Gracilaria vermiculophylla (Ohmi) Papenf., an agar‐producing red alga introduced from northeast Asia to Europe and North America, is often highly abundant in invaded areas. To assay its genetic diversity and identify the putative source of invasive populations, we analyzed the mitochondrial cytochrome c oxidase subunit I (cox1) gene from 312 individuals of G. vermiculophylla collected in 37 native and 32 introduced locations. A total of 19 haplotypes were detected: 17 in northeast Asia and three in Europe and eastern and western North America, with only one shared among all regions. The shared haplotype was present in all introduced populations and in ~99% of individuals in the introduced areas. This haplotype was also found at three native locations in east Korea, west Japan, and eastern Russia. Both haplotype and nucleotide diversities were extremely low in Europe and North America compared to northeast Asia. Our study indicates that the East Sea/Sea of Japan is a likely donor region of the invasive populations of G. vermiculophylla in the east and west Atlantic and the east Pacific.  相似文献   

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