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1.
The relationships between Cinara (Cupressobium) aphids inhabiting woody parts and leaves of conifers belonging to Cupressaceae have been studied using a mitochondrial gene (COI) and a nuclear gene (EF1-α). Based on the COI sequences, genetic distances between species ranged from 5.6 % between Cinara (C.) tujafilina (del Guercio) and Cinara (C.) juniperi (De Geer) to 10.5 % between C. (C.) tujafilina and Cinara (C.) mordvilkoi (Pa?ek). Genetic distances among EF1-α sequences were lower and showed from 0.1 % between C. cupressi and C. juniperi to 2.3 % between C. tujafilina and C. mordvilkoi. Molecular phylogenetic trees were constructed using the Bayesian inference (BI) phylogenetic analysis and maximum parsimony (MP) criterion. Phylogenetic trees obtained based on COI and EF1-α marker genes created two sister clades. Our results indicate that Cinara (Cupressobium) are a monophyletic group of aphids. Phylogenetic relationships amongst Cupressobium aphids do not result from the association with the host plant, but from the feeding site on the host plant or an ability to change the microhabitat on the plant. As closely related species inhabit similar microhabitats on different host plants, it suggests that the host switching is the main mode of speciation in this subgenus.  相似文献   

2.
Recent research has shown the bioprospecting of endophytic fungi from Cupressaceae. Here, we further uncover that the healthy cypress plants such as Cupressus arizonica, Cupressus sempervirens var. cereiformis, and Thuja orientalis host highly bioactive endophytic Alternaria fungal species. Indeed, endophytic Alternaria alternata, Alternaria pellucida, and Alternaria tangelonis were recovered from healthy Cupressaceous trees. Biodiversity and bioactivity of recovered endophytic Alternaria species were a matter of biogeography and host identity. We further extracted such Alternaria’s metabolites and highlighted their significant antiproliferative, growth inhibitory, and antibacterial activities against the model target fungus Pyricularia oryzae and the model pathogenic bacteria Bacillus sp., Erwinia amylovora, and Pseudomonas syringae. In vitro assays also indicated that endophytic Alternaria species significantly inhibited the growth of cypress fungal phytopathogens Diplodia seriata, Phaeobotryon cupressi, and Spencermartinsia viticola. In conclusion, since the recovered Alternaria species were originally reported as pathogenic and allergenic fungi, our findings suggest a possible ecological niche for them inside the foliar tissues of Cupressaceous trees. Moreover, in this study, the significant bioactivities of endophytic Alternaria species in association with Cupressaceae plant family are reported.  相似文献   

3.
Two new species ofCarex (Cyperaceae) are described from southern South America.Carex transandina occurs in naturally-deposited rock talus and scree in southwestern Chile andC. austroamericana occurs in the Patagonian steppe in Chile and Argentina. In the past, specimens ofC. austroamericana have been erroneously referred toC. andina var.subabscondita Kük., and it is shown here that the latter entity is conspecific withC. nelmesiana Barros. The taxonomy ofC. nelmesiana is presented and its relationship to other members ofCarex sect.Junciformes (Boeckl.) Kük. is discussed.  相似文献   

4.
The South American fish genus Percichthys, due to its great morphological variation, has included several nominal species throughout a long history. However, current genetic analyses signal the existence of only two extant species, Percichthys melanops Girard in Chile (west of the Andes) and P. trucha (Valenciennes) in Chile and Argentina (west and east of the Andes). Here the morphological variation of free embryos, larvae, and juveniles of P. trucha was analyzed using linear measurements and geometric morphometrics. Early morphological variation and compensatory growth were examined using sibling free embryos and larva. Morphological consequences of experimentally controlled food treatments were explored in juveniles. Our results showed individual variation in the size of the yolk-sac of free embryos and in the duration of the mixed feeding period. Phenotypic convergence of the upper jaw length from larva to juveniles and adults, and the causal relationship between diet and head shape was found to change as a consequence of controlled feeding. Embryonic, larval, and juvenile morphological variation and phenotypic plasticity observed in P. trucha pinpoint a possible cause for the shape variation observed in the wild. Phenotypic plasticity allows P. trucha to exploit different trophic resources and to occupy different habitats in low biodiversity lakes of Patagonia, being a major factor taking part in the past and present success of P. trucha.  相似文献   

5.
Trisetacus juniperinus (Nalepa) sensu Keifer (Acari: Eriophyoidea: Phytoptidae) causes irregular development of buds, shoot deformations and stunted growth of trees, resulting in a serious threat to nurseries and young stands of Cupressus sempervirens L. (Mediterranean cypress). Recently, some cypress clones selected for their resistance to the fungal canker agent Seiridium cardinale (Wag.) have shown high susceptibility to the mite. Considering its tiny body, its hidden lifestyle inside the buds and the probable occurrence of other species (the vagrant Epitrimerus cupressi (Keifer) is common on the Mediterranean cypress in Italy), detection and monitoring of T. juniperinus require taxonomic expertise and are often time-consuming and challenging before serious damage is discernible. In the present study, a rapid, cost-effective PCR-based method was developed and validated to detect T. juniperinus on cypresses. The cytochrome c oxidase subunit I gene was amplified with degenerate and specific primers, but the latter were the only ones able to discriminate between T. juniperinus and E. cupressi. PCR products distinguished the two species both in a pool of individuals in a mixed population of both species and in single individuals, indicating the sensitivity of the detection method. PCR–RFLP (restriction fragment length polymorphism) by means of XmnI and XbaI endonucleases separated the two species. Furthermore, a washing-sieving protocol was used to make mite collection from the tree sample faster and simpler; this procedure did not interfere with the molecular detection of the species. The possibility of the routine use of this assay to monitor quarantine eriophyoids infesting plant material is discussed.  相似文献   

6.
7.
The flagellate Crithidia bombi and the neogregarine Apicystis bombi have been found in individuals of Bombus terrestris, a Palaearctic species of bumble bee commercially reared and shipped worldwide for pollination services. B. terrestris has recently entered into the northwestern Patagonia region of Argentina from Chile, where it was introduced in 1998. Prevalence was 21.6% for C. bombi and 3.6% for A. bombi (n = 111). The pathogens were not detected in 441 bumble bees belonging to five of the eight known Argentine native species (Bombus atratus, Bombus morio, Bombus bellicosus, Bombus opifex, Bombus tucumanus) collected elsewhere in the country. Although the absence of natural occurrence of C. bombi and A. bombi in Argentine native bumble bees cannot be ascertained at present due to the limited surveys performed, it is important to report their detection in invasive B. terrestris. The invasion event is relatively recent and the accompanying pathogens are not species specific within the genus Bombus.  相似文献   

8.
Abstract.
  • 1 In Kenya, the aphid Cinara cupressi (Buckton) has an aggregated distribution across individuals of its host plant, the Mexican cypress, Cupressus lusitanica (Mill).
  • 2 There are significant differences in host plant quality: C.cupressi nymphs transplanted onto cypress trees with low aphid infestations are significantly less likely to establish than aphids transplanted onto trees with high aphid infestations.
  • 3 Given that some transplanted nymphs establish, the previous level of infestation does not influence aphid survival.
  • 4 Evidence for local adaptation to individual plants was not found: nymphs transplanted to the trees from which their parents were collected neither established more readily nor showed lower mortality than those transplanted to other trees with similar levels of infestation. Therefore the variation in host plant quality has not led to the development of local adaptation to particular host plants.
  相似文献   

9.
Phenotypic variability and mixing of material due to massive cultivation for commercial purposes has contributed to the taxonomic confusion ofGracilaria in Chile. At least four species with cylindrical thalli and similar morphology have been recorded. However, since establishment ofG. chilensis, most of the collected thalli have been attributed to this species despite the lack of diagnostic features. In an attempt to resolve whetherGracilaria from 3 localities where it grows in natural and artificial populations belongs to the same species, gametophytic samples were compared by applying RAPD-PCR to their total DNA. This was analysed using 25 different 10-mer primers from which 21 revealed polymorphism within and between populations. Similarity matrices and cluster analyses were performed based on the presence/absence of bands representing fragments of DNA generated by random amplification. Similarity values between two of the populations were equivalent to those detected within a third, indicating the mixing of genetic material due to transplant between the two former localities. Similarities between samples of ChileanGracilaria andG. tenuistipitata from Sweden are considerably lower (0.45–0.53) than those between populations from Chile (0.74–0.88), confirming the existence of a single specific taxon,G. chilensis, in these three localities.  相似文献   

10.
Leaf flavonoids were isolated and identified from 54 populations representing all seven species of Robinsonia, a genus of dioecious rosette trees endemic to the Juan Fernandez Islands. Fourteen compounds were detected consisting of flavonols, flavones, flavanones and dihydroflavonols. The distribution of these compounds in Robinsonia largely corresponds to specific and sectional limits based on morphological data. The morphologically similar species, R. gayana and R. thurifera, have identical flavonol profiles (derivatives of quercetin). Likewise, the closely related R. evenia and R. masafuerae are unique in the genus by possessing flavones. The inclusion of Rhetinodendron (i.e., R. berteroi) in Robinsonia is supported by its strong flavonoid similarity with species in two other sections of the genus. The morphologically diverse section Eleutherolepis exhibits the greatest flavonoid variation of any section, and only here are found flavones, flavanones and dihydroflavonols. The direction of flavonoid evolution in Robinsonia is hypothesized to be from fewer to more classes of compounds. Biosynthetic considerations suggest that this gain in compounds is due both to a gain of an additional enzymatic step and to the sequestering of precursors. This interpretation of direction of flavonoid evolution is in agreement with several lines of evidence including the flavonoid chemistry of the hypothesized outgroup (i.e., species of Senecio on mainland Chile), the ages of the two islands, and morphological trends.  相似文献   

11.
12.
We studied the influence of seven habitat variables, including tree species, for nesting by the Black-faced Ibis (Theristicus melanopis melanopis) in an urban area of southern Chile. Variables were compared between 30 trees with nests and 30 randomly selected trees without nests. Nests were found in big trees with large diameters and heights. However, the only variable found to have a significant effect on site selection was tree species, which explained 57.9% of data variability (deviance) and suggested a selection of exotic conifers, mainly Douglas fir (Pseudotsuga menziesii). Tree species and tree diameter also had significant effects upon the number of nests per tree, jointly explaining 68.9% of data deviance. Our results suggest that in urban environments the Black-faced Ibis uses larger trees that provide greater nest stability and protection.  相似文献   

13.
Caluromys is considered to be one of the most ancient genera of extant marsupials and is positioned among the basal taxa of the family Didelphidae. At least two species occur in Brazil, C. philander and C. lanatus, both of which have 2n = 14 chromosomes. For the first time, we present evidence of an intrapopulation polymorphism of the sexual chromosome pair in C. philander females from the Central Amazon region. Detailed cytogenetic results of animals from three localities on the Amazon region were analyzed using classical cytogenetics (NOR, C-Band and G-Band) and molecular techniques (18S rDNA and telomere probes). Similar to other conspecific individuals, the diploid number of these animals is 2n = 14, and their fundamental number is 24, with NOR present on the 6th autosomal pair. The X chromosome presented variation detectable by G banding, suggesting a pericentric inversion.  相似文献   

14.
The island of St Helena in the South Atlantic Ocean has a rich endemic flora, with 10 endemic genera and 45 recognised endemic species. However, populations of most endemic species have undergone dramatic reductions or extinction due to over-exploitation, habitat destruction and competition from invasive species. Consequently, endemic species are likely to have lost genetic variation, in some cases to extreme degrees. Here, the entire extant wild populations and all planted trees in seed orchards, of two critically endangered species in the endemic genus Commidendrum (Asteraceae), C. rotundifolium and C. spurium, were sampled to assess levels of genetic variation and inbreeding. Six new microsatellite loci were developed from next-generation sequence data, and a total of 190 samples were genotyped. Some seed orchard trees contained alleles from both wild C. rotundifolium and C. spurium indicating they could be hybrids and that some backcrossing may have occurred. Some of these trees were more similar to C. rotundifolium than C. spurium both genetically and morphologically. Importantly, allelic variation was detected in the putative hybrids that was not present in wild material. C. rotundifolium is represented by just two individuals one wild and one planted and C. spurium by seven, therefore the seed orchard trees comprise an important part of the total remaining genetic diversity in the genus Commidendrum.  相似文献   

15.
The cultivation of tropical fruit trees has grown considerably in the state of Bahia, northeastern Brazil. Some of these have been severely attacked by phytophagous mites, which are usually controlled by the use of chemical pesticides. However, there is today a growing interest for the adoption of less aggressive measures of pest control, as for example the use of predatory mites. Most of the plant-inhabiting predatory mites belong to the family Phytoseiidae. The objective of this paper is to report the phytoseiid species found in an intensive survey conducted on cultivated tropical fruit trees in fifteen localities of the southern coast of Bahia. Measurements of relevant morphological characters are provided for each species, to complement the understanding of the morphological variation of these species. Twenty-nine species of sixteen genera were identified. A key was elaborated to assist in the separation of these species. Fifteen species are reported for the first time in the state, raising to sixty-six the number of species of this family now known from Bahia. Seventy-two percent of the species collected belong to Amblyseiinae, followed by Typhlodrominae (21%) and Phytoseiinae (7%). The most diverse genus was Amblyseius. Amblyseius operculatus De Leon was the most frequent and abundant species. Studies should be conducted to evaluate the possible role of the most common predators as control agents of the phytophagous mites co-occurring with them.  相似文献   

16.
A total of 2,868 individuals of 47 species of chaetodontids were examined for faustulids at seven major localities in the Tropical Indo-West Pacific (TIWP). Combined morphological and molecular analyses allowed us to describe Paradiscogaster oxleyi n. sp. from three localities in the TIWP and in three host species, Chaetodon lunulatus Quoy & Gaimard (type-host), C. ornatissimus Cuvier and C. meyeri Bloch & Schneider. Molecular analysis of the ITS2 region of rDNA from two host species and three localities supports the morphology-based conclusion that P. oxleyi n. sp. is the same species at the three localities. Paradiscogaster flindersi Bray, Cribb & Barker, 1994 is reported from three new localities in the TIWP and is now known from 13 chaetodontid species. Sequences from samples consistent with P. flindersi differed from those from P. oxleyi n. sp. in 11–12 base pairs. The host ranges of the two species overlap broadly. Neither species was found in French Polynesia but both were found at Swain Reefs on the Great Barrier Reef. Only one of the two species was found at each of the five other sites. Both species occur almost exclusively in specialist corallivores allowing the inference that the metacercariae occur in corals. Finally, a key to the species of Paradiscogaster is provided.  相似文献   

17.
A molecular study of the wetland pleurocarpous moss Hamatocaulis vernicosus (Mitt.) Hedenäs, based on the ITS region, the trnL-trnF region, and rpl16 revealed two cryptic species. One of these is widespread in Europe, and was also sampled from several localities in Minnesota (United States). The other cryptic species occurs only south of the boreal zone in Europe, and was in addition sampled from single localities in Peru and northernmost Asiatic Russian Federation. Although it seems likely that the southern species colonized parts of Europe from southern refugia after the last glaciation, its wide distribution outside Europe indicates that the speciation event is unrelated to the European glacial history. No correlations could be found between variation in habitat preferences (pH and electric conductivity) and molecular variation.  相似文献   

18.
Abstract

Previous reports of Carulaspis visci (Schrank) in New Zealand are considered to be misidentifications of C. juniperi (Bouché), the juniper scale. The known hosts (Cupressaceae and Taxodiaceae), distribution (all South Island localities), and a record of a parasite (Aspidiotiphagus citrinus (Craw), Aphelinidae) of C. juniperi in New Zealand are given.  相似文献   

19.
Carlota gen. n., with one included species C. coigue sp. n., is described and illustrated from the Valdivian forests of Chile. The relationships of this genus to other Agrypnini from Chile are discussed and generic key for Chilean Agrypninae genera is provided.  相似文献   

20.
Austrocedrus chilensis is a South American conifer broadly distributed across the subtropical and extratropical Andes that is widely utilized in tree-ring studies. This species has clear annual growth rings that are sensitive to the moisture supply and has been extensively used to reconstruct the past hydroclimate during the last millennium. Despite a great number of dendrochronological studies based on tree-ring width, little is known about the potential of the species to record intra-annual anomalies and particularly frost rings. In this study, the main traits of A. chilensis frost rings were studied and the ability of this endemic Cupressaceae to record spring frosts at five sites across a latitudinal gradient between the Mediterranean and Northern Patagonian Andes was evaluated. The average ages of trees in the study sites varied from 168 to 343 years, with minimum and maximum ages of 33 and 919 years. The results indicated that 85% of the frost rings occurred at the beginning of the earlywood and 15% showed a mid intra-ring position. Regarding the portion of the ring circumference affected by frost damage in cross sections, 59% of the injuries partially affected the entire ring, 30% affected the complete ring circumference, and 11% resulted in a ring fracture. Freezing temperatures that generated frost rings in A. chilensis from the upper treeline coincided with events below 0 °C recorded in the agricultural Central Valley of Chile. We estimated the potential time window of the formation of A. chilensis frost rings over a two and a half month period from the end of September to mid-November (early spring). Our results indicated that tree age was a determinant factor affecting the ability of trees to record frost rings. The maximum frequency of frost rings occurred at 12 years and the maximum age at which 95% of the total frost injuries occurred within our network was about 120 years. Both the exceptional longevity and the excellent state of preservation of relict wood demonstrates that A. chilensis frost rings provide a reliable proxy for monitoring and reconstructing late-spring frost events in central Chile.  相似文献   

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