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1.
The following new combinations are made:Myrteola phylicoides (Benth.) Landrum,Myrteola phylicoides var.glabrata (Berg) Landrum,Myrceugenia alpigena var.fuliginea (Berg) Landrum,Myrceugenia ovata var.regnelliana (Berg) Landrum, andMyrceugenia pilotantha var.nothorufa (Legrand) Landrum.  相似文献   

2.
The rarely cultivated South American myrtle, Myrceugenia lanceolata (Juss. ex J. St.‐Hil.) Kausel, is illustrated, and its cultivation is discussed. The career of its discoverer, Joseph Dombey (1742–1794) is reviewed.  相似文献   

3.
The regeneration of canopy and subeanopy species in a mid-elevation, primary rain forest in the Coastal Range of Isla de Chiloé (42°30S), in the cold-temperate region of Chile, was studied by comparing seedling and sapling abundances under the forest canopy, and within 36 tree-fall gaps. The forest was dominated byAmomyrtus luma andLaurelia philippiana (33 and 32% of the main canopy individuals), and two subcanopy species (Myrceugenia ovata, andMyrceugenia planipes) were also important. Uncommon species in the canopy wereDrimys winteri, Amomyrtus meli, andRaphithamnus spinosus. Tree-fall gaps were created generally by the fall of several trees, and the main canopy species were the principal gap-makers. Gap sizes varied between 28 and 972 m2, with a mean of 197 m2. Seedling and sapling abundances indicate that the dominant species are capable of regenerating below the canopy, but they also germinate and show enhanced growth within small light gaps. For one of the common subcanopy species (M. planipes) and the two infrequent canopy species (D. winteri, andA. meli) regeneration seems to depend entirely on tree-fall gaps. Thus, in this forest, light gaps allow the persistence of infrequent canopy species, but seem less important for the regeneration and maintenance of dominant canopy species.  相似文献   

4.
We study the effect of ingestion by birds on seed germination and theconsequences of absence of dispersal, with the persistency of the seedsinside the fruit. We collected seeds of four woody species ofthe temperate rainforest of Chiloé: Gaultheriamucronata, Luma apiculata, Myrteolanummularia, and Myrceugenia planipes. The seedstested had the following origins: 1) Ingested seeds: seeds collected fromthe feces of birds, 2) Extracted seeds: seeds obtained directly from thefruits, and 3) Intact fruits: fruits collected directly from the plants.Germination of Myrceugenia planipes under greenhouseconditions, Luma apiculata, and Myrteolanummularia under laboratory conditions, and Gaultheriamucronata under both conditions was analyzed. We found that the seedsreach their maximum germination between 15–20 days after sowing, withthe exception of those of G. mucronata sown in the greenhouse,which showed a low germination rate. In the greenhouse assay, seeds ofG. mucronata ingested by birds, seeds extracted manuallyfrom the fruits, and seeds inside the fruits did not show significant differencesin their germination percentages. In the laboratory assays, the seeds ofG. mucronata and M. nummulariaingested by birds and the seeds extracted manually from the fruits also did not show anysignificant difference in germination. Under laboratory conditions, theseeds of L. apiculata ingested by birds presented astatistically greater percentage of germination than the seeds extracted manually.Under greenhouse conditions, seeds of M. planipes ingestedby birds did not present a statistically different germination percentage fromthose seeds extracted from the fruits. The seeds of M.planipes, and L. apiculata inside the intactfruits did not germinate. We conclude that birds do not affect the seedviability of any of the four species studied.  相似文献   

5.
With the aim of correlating the pericarp structure with current phylogenies of Myrteae, this study describes the ontogeny in five species included in five out of the six South American clades of the tribe. In these taxa, the outer and inner ovarian epidermis gives rise to the exocarp and the endocarp, respectively, both with 1 layer. In the mesocarp, derived from the ovarian mesophyll, secretory cavities are arranged into a circle just below the exocarp and near the endocarp in Campomanesia adamantium; only below the exocarp in Eugenia pitanga and Myrcia multiflora; more internally in Myrciaria cuspidata, and below the exocarp and throughout the mesophyll in Myrceugenia alpigena. The promising traits for phylogenetic studies in the group include: direction of elongation of pericarp layers, regions that develop most in relation to the circle of larger vascular bundles, differentiation of spongy and sclerenchymatous tissues and position of secretory cavities.  相似文献   

6.
We investigated the feeding of three small-sized sigmodontine rodents (Oligoryzomys nigripes Olfers, 1818,Akodon montensis Thomas, 1913, andDelomys dorsalis Hensel, 1872) on fruiting plants in theAraucaria forest of southern Brazil. We offered to wild-captured animals fruits of 22 plant species in 14 families. For each individual, we recorded consumption patterns of pulp and seed. We also analyzed fecal samples to determine the relative abundance of invertebrates, fruit and seed parts, and fungi. The three rodents showed marked potential frugivory, feeding on most species offered. OnlyO. nigripes showed differences in relation to seed-size categories, consuming a high proportion of ‘small’ (diameter ≤2.5 mm) vs ‘large’ seeds. The rodents may be involved in seed dispersion of three plant species, by defecation of viable seeds of twoLeandra (Melastomataceae) species and also by removing the pulp ofMyrceugenia miersiana (Myrtaceae) fruits without swallowing or damaging their relatively large seeds, thus, potentially increasing germination rates ofM. miersiana. Diet analyses indicated no significant difference among proportions of seed/fruit in the fecal samples of the three species of rodents (33 to 41% of plant material). Our results suggest that the three focal species are the main small-mammal seed predators on the ground ofAraucaria forests.  相似文献   

7.
8.
The analysis of volatile oil content of Myrceugenia cucullata, a treelet from southern Brazilian montane forests, was investigated. Two markedly distinct chemotypes were identified. One of them is dominated by (E)-nerolidol and the other by (−)-α- and (−)-β-pinenes. Field observations showed a distinct ecological behaviour of plants with distinct chemical compositions, and a closer morphological analysis hints to a possible separation of them. The diverse oil composition is discussed and the possibility of specific segregation of the chemotypes is commented.  相似文献   

9.
Myrceugenia is a genus endemic to South America with a disjunct distribution: 12 species occurring mainly in central Chile and approximately 25 in southeastern Brazil. Relationships are reconstructed within Myrceugenia from four plastid markers (partial trnK-matK, rpl32-trnL, trnQ-5'rps16 and rpl16) and two ribosomal nuclear regions (ETS and ITS) using maximum parsimony and Bayesian analyses. Relationships inferred previously from morphological data are not completely consistent with those from molecular data. All molecular analyses support the hypothesis that Myrceugenia is monophyletic, except for M. fernadeziana that falls outside the genus. Chilean species and Brazilian species form two separate lineages. Chilean species form three early diverging clades, whereas Brazilian species are a strongly supported monophyletic group in a terminal position. Least average evolutionary divergence, low resolution, short branches, and high species diversity found in the Brazilian clade suggest rapid radiation. Geographical distributions and phylogenetic reconstructions suggest that extant Myrceugenia species arose in northern Chile followed by colonization southward and finally to the Juan Fernández Islands and southeastern Brazil.  相似文献   

10.
A phylogenetic study of selected fleshy-fruited genera of the Myrtaceae was conducted using sequences from the ITS region of nuclear DNA and the psbA-trnH region of plastid DNA. Studies to date have suggested that the fleshy-fruited state has arisen on several occasions in the Myrtaceae. The previously accepted and predominantly Neotropical tribe Myrteae has traditionally been divided into three groups, the subtribes Myrtinae, Eugeniinae and Myrciinae. This subtribal arrangement is analysed in detail here for the first time. The monophyly of the tribe and subtribes are tested and relationships of the genera within them, in particular those of the Myrciinae and anomalous genera sometimes associated with it, are discussed. Combined analyses of these two DNA regions revealed 40 shortest trees, all of which resolve Myrteae (excluding the Acmena group) as monophyletic. Myrciinae appears to be monophyletic whereas Myrtinae and Eugeniinae appear polyphyletic. The phylogenetic positions and relationships of the anomalous genera Myrceugenia, Luma and Blepharocalyx are unclear, but Myrceugenia is never included within the Myrciinae s.str. A Myrciinae s.str. clade emerges within which Myrcia, Calyptranthes and Marlierea appear polyphyletic. Clades emerge, however, that may reflect some natural groupings within the subtribe.We thank David Simpson, Lazlo Csiba, Edith Kapinos and many others from Kew for invaluable advice and support. It would not have been possible to collect the Brazilian samples without the patience and careful guidance of Dr. Vinicius C. Souza, Fiorella F. Mazine (Universidade de São Paulo, ESALQ), Professor Gert Hatschbach, Joel M. de Silva (Museu Botânico Municipal, Curitiba) and many others from the ESA and MBM herbaria. Thanks also to Les Landrum, Andrew Salywon, Marcos Sobral and an anonymous reviewer for helpful comments at different stages of this work. British Airways are gratefully acknowledged for providing a flight to Brazil under their Community and Conservation programme.  相似文献   

11.

Questions

The exceptional occurrence of tall rain forest patches on foggy coastal mountaintops, surrounded by extensive xerophytic shrublands, suggests an important role of plant–plant interactions in the origin and persistence of these patches in semi‐arid Chile. We asked whether facilitation by shrubs can explain the growth and survival of rain forest tree species, and whether shrub effects depend on the identity of the shrub species itself, the drought tolerance of the tree species and the position of shrubs in regard to wind direction.

Location

Open area–shrubland–forest matrix, Fray Jorge Forest National Park, Chile.

Methods

We recorded survival after 12 years of a ~3600 tree saplings plantation (originally ~30‐cm tall individuals) of Aextoxicon punctatum, Myrceugenia correifolia and Drimys winteri placed outside forests, beneath the shrub Baccharis vernalis, and in open (shrub‐free) areas. We assessed the effects of neighbouring shrubs and soil humidity on survival and growth along a gradient related to the direction of fog movement.

Results

B. vernalis had a clear facilitative effect on tree establishment and survival since, after ~12 years, saplings only survived beneath the shrub canopy. Long‐term survival strongly depended on tree species identity, drought tolerance and position along the soil moisture gradient, with higher survival of A. punctatum (>35%) and M. correifolia (>14%) at sites on wind‐ and fog‐exposed shrubland areas. Sites occupied by the shrub Aristeguietia salvia were unsuitable for trees, presumably due to drier conditions than under B. vernalis.

Conclusions

Interactions between shrubs and fog‐dependent tree species in dry areas revealed a strong, long‐lasting facilitation effect on planted tree's survival and growth. Shrubs acted as benefactors, providing sites suitable for tree growth. Sapling mortality in the shrubland interior was caused by lower soil moisture, the consequence of lower fog loads in the air and thus insufficient facilitation. While B. vernalis was a key ecosystem engineer (nurse) and intercepted fog water that dripped to trees planted underneath, drier sites with A. salvia were unsuitable for trees. Consequently, nurse effects related to water input are strongly site and species specific, with facilitation by shrubs providing a plausible explanation for the initiation of forest patches in this semi‐arid landscape.  相似文献   

12.
The biogeography of microorganisms is poorly understood and how microbial diversity is structured is still an open debate. We investigated the processes underlying the fungal endophyte assemblages of phylogenetically related Myrtae host tree species at different spatial scales: regional, 101–5 000 km; local, 0–100 km; and microscale, 0–1 km. A total of 939 isolates was obtained and assigned to 51 distinct MOTUs based on the sequencing of the nrITS region. At regional scales, geographic distance was responsible for explaining the fungal community similarity, while, at a local scale, it was the environmental distance. Moreover, fungal endophytes exhibit preference in the colonization of Luma apiculata but not for Myrceugenia ovata var. nanophylla. Our results suggest that fungal endophytes are not randomly distributed and are influenced by both geographic and environment distances depending on the spatial scale analysed.  相似文献   

13.
Twenty-one flavonoids were isolated from the leaves of two endemic species ofMyrceugenia on the Juan Fernandez Islands,M. fernandeziana andM. schulzei, from two related species from Brazil,M. campestris andM. rufescens, and from five species from continental Chile,M. colchaguensis, M. exsucca, M. lanceolata, M. pinifolia, andM. rufa. A phenetic analysis was used to evaluate chemical similarities.Myrceugenia campestris andM. rufescens appear most closely related to each other based on flavonoid profiles, and they are also different from the other seven species. The two endemic species in the Juan Fernandez Islands,M. fernandeziana andM. schulzei, group with the continental Chilean species. The former is most closely related toM. lanceolata, and the latter clusters withM. exsucca, although somewhat distantly. The results suggest that the two Juan Fernandez endemics are derived from two introductions from the Chilean continent and not from immigrants from the eastern side of the Andes.  相似文献   

14.
To establish relationships among the genera Blepharocalyx, Luma, and Myrceugenia, the phylogeny of tribe Myrteae was reconstructed based on secondary structures of the sequences of ITS (ITS1-5.8S-ITS2) and ETS regions from 93 taxa belonging to 29 genera. The DNA sequences were aligned according to their secondary structure and analysed with Bayesian inference (BI) using base substitution models for RNA, which can differentiate between the regions consisting of base pairs (helices) and unpaired bases (loops). The best-fit models were RNA7C for ITS and RNA7B for ETS, which differ in how they predict double substitutions and symmetry of the frequency of base pairs. The phylogenetic hypothesis was compared with results obtained using classical 4-state models, the results of maximum parsimony, and using sequence alignment without considering the secondary structure. Analyses show low support along the backbone of the consensus trees, those using substitution models of paired sites showing more highly supported derived clades than substitution models of independent sites. All tests were consistent and differed in the positioning of certain groups, but they also showed that Blepharocalyx, Luma, and Myrceugenia arise from three independent lineages that are not closely related. The substitution model for RNA shows that Luma is a monophyletic group and sister to the other genera of Myrteae, except for Myrtus communis. Myrceugenia appears as a monophyletic group, except for M. fernandeziana, which is related to Blepharocalyx, a genus that appears to be biphyletic.  相似文献   

15.
The study of functional traits and physiological mechanisms determining species’ drought tolerance is important for the prediction of their responses to climatic change. Fog-dependent forest patches in semiarid regions are a good study system with which to gain an understanding of species’ responses to increasing aridity and patch fragmentation. Here we measured leaf and hydraulic traits for three dominant species with contrasting distributions within patches in relict, fog-dependent forests in semiarid Chile. In addition, we assessed pressure–volume curve parameters in trees growing at a dry leeward edge and wet patch core. We predicted species would display contrasting suites of traits according to local water availability: from one end favoring water conservation and reducing cavitation risk, and from the opposite end favoring photosynthetic and hydraulic efficiency. Consistent with our hypothesis, we identified a continuum of water use strategies explaining species distribution along a small-scale moisture gradient. Drimys winteri, a tree restricted to the humid core, showed traits allowing efficient water transport and high carbon gain; in contrast, Myrceugenia correifolia, a tree that occurs in the drier patch edges, exhibited traits promoting water conservation and lower gas exchange rates, as well low water potential at turgor loss point. The most widespread species, Aextoxicon punctatum, showed intermediate trait values. Osmotic compensatory mechanism was detected in M. correifolia, but not in A. punctatum. We show that partitioning of the pronounced soil moisture gradients from patch cores to leeward edges among tree species is driven by differential drought tolerance. Such differences indicate that trees have contrasting abilities to cope with future reductions in soil moisture.  相似文献   

16.
This article documents the addition of 299 microsatellite marker loci and nine pairs of single-nucleotide polymorphism (SNP) EPIC primers to the Molecular Ecology Resources (MER) Database. Loci were developed for the following species: Alosa pseudoharengus, Alosa aestivalis, Aphis spiraecola, Argopecten purpuratus, Coreoleuciscus splendidus, Garra gotyla, Hippodamia convergens, Linnaea borealis, Menippe mercenaria, Menippe adina, Parus major, Pinus densiflora, Portunus trituberculatus, Procontarinia mangiferae, Rhynchophorus ferrugineus, Schizothorax richardsonii, Scophthalmus rhombus, Tetraponera aethiops, Thaumetopoea pityocampa, Tuta absoluta and Ugni molinae. These loci were cross-tested on the following species: Barilius bendelisis, Chiromantes haematocheir, Eriocheir sinensis, Eucalyptus camaldulensis, Eucalyptus cladocalix, Eucalyptus globulus, Garra litaninsis vishwanath, Garra para lissorhynchus, Guindilla trinervis, Hemigrapsus sanguineus, Luma chequen. Guayaba, Myrceugenia colchagüensis, Myrceugenia correifolia, Myrceugenia exsucca, Parasesarma plicatum, Parus major, Portunus pelagicus, Psidium guayaba, Schizothorax richardsonii, Scophthalmus maximus, Tetraponera latifrons, Thaumetopoea bonjeani, Thaumetopoea ispartensis, Thaumetopoea libanotica, Thaumetopoea pinivora, Thaumetopoea pityocampa ena clade, Thaumetopoea solitaria, Thaumetopoea wilkinsoni and Tor putitora. This article also documents the addition of nine EPIC primer pairs for Euphaea decorata, Euphaea formosa, Euphaea ornata and Euphaea yayeyamana.  相似文献   

17.
18.
A taxonomic review of the Korean Lymantria Hübner, 1819 was conducted. A total of nine species of five subgenera with two unrecorded species are listed: Lymantria (Porthetria) dispar Linnaeus 1758, L. (P.) xylina Swinhoe 1903, L. (Lymantria) monacha (Linnaeus 1758), L. (L.) minomonis Matsumura 1933 (new to Korea), L. (L.) similis monachoides Schintlimeister 2004 (new to Korea), L. (L.) lucescens (Butler 1881), L. (Nyctria) mathura Moore 1865, L. (Collentria) fumida Butler 1877, and L. (Spinotria) bantaizana Matsumura 1933. Lymantria (Lymantria) minomonis and L. (L.) similis monachoides are newly added to the Korean fauna. Lymantria (L.) minomonis was found only on Bogildo Island of Jeollanam‐do in the southern part of Korea, and L. (L.) similis monachoides was collected in central Korea. Lymantria (Porthetria) xylina and L. (Collentria) fumida were not examined in this study, and it is considered that the previous records were due to misidentification or they are only distributed in the northern part of the Korean Peninsula. We provide diagnoses of two unrecorded species and adult habitus and genitalia photos of the Korean Lymantria species.  相似文献   

19.
Recently, two Bacillus thuringiensis strains were reported to synthesize parasporal inclusion bodies made not of the expected crystal (Cry) proteins but rather of the surface layer proteins (SLP) Sap (encoded by sap) and EA1 (encoded by eag), respectively. Whether the presence of the sap and eag genes is restricted to these two B. thuringiensis strains or ubiquitous in B. thuringiensis is unknown. We report here the distribution of the sap and eag genes in B. thuringiensis. Strains in the Bacillus cereus group were added for comparison purposes. We show that sap and eag are either present in tandem in 35% of the B. thuringiensis strains analysed and absent in 65% of the strains. When absent, a different tandem, the lytB/lytA cell wall hydrolase genes, is present. The distribution of the sap and eag S-layer and the lytB/lytA cell wall hydrolase genes is not species-specific in B. thuringiensis, B. cereus and Bacillus weihenstephanensis. Bacillus anthracis and Bacillus mycoides harbor sap and eag but not lytB/lytA. The sap, eag and lytB/lytA genes were absent in Bacillus pseudomycoides. Clearly, the distribution of the sap and eag S-layer and the lytB/lytA cell wall hydrolase genes in B. thuringiensis and in the Bacillus cereus group is mutually exclusive. We also showed that two genes involved in cell wall metabolism, csaA and csaB, are present not only upstream of the sap and eag S-layer genes, but also upstream of the lytB/lytA tandem in strains where sap and eag are absent. Bootstrapped neighbor-joining trees were inferred from the translated amino acid sequences of sap, eag and the tandem lytB/lytA, respectively.  相似文献   

20.
The S locus and its flanking regions in the genus Prunus (Rosaceae) contain four pollen-expressed F-box genes. These genes contain the S locus F-box genes with low allelic sequence polymorphism genes 1, 2, and 3 (SLFL1, SLFL2, and SLFL3) as well as the putative pollen S gene, named the S haplotype-specific F-box protein gene (SFB). As much less information is available on the function of SLFLs than that of SFB, we analyzed the SLFLs of six S haplotypes of sweet cherry (Prunus avium) in this study. Genomic DNA blot analysis and the isolation of SLFL1 showed that the SLFL1 gene in a functional self-incompatible S 3 haplotype is deleted and only a partial sequence resembling SLFL1 is left in the S 3 locus region, suggesting that SLFL1 by itself is not directly involved in either the GSI reaction or pollen-tube growth. Genomic DNA blot analysis showed that there was no substantial modification or mutation in SLFL2 and SLFL3. A phylogenic analysis of F-box genes in the rosaceous S locus and its border regions showed that Prunus SLFLs were more closely related to maloid S locus F-box brothers than to Prunus SFBs. The functions of SLFLs and the evolution of self-incompatibility in Prunus are discussed based on these results. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. The nucleotide sequence data reported appear in the DDBJ, EMBL, and GenBank Nucleotide Sequence Databases under the accession numbers, AB360339, AB360340, AB360341, and AB360342, for SLFL1-S 1 , SLFL1-S 2 , SLFL1-S 5 , and SLFL1-S 6 , respectively.  相似文献   

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