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1.
Phylogenetic analyses based on protein-encoding gene exons and introns of ATP citrate lyase (ACL1), beta tubulin (TUB), the largest subunit of RNA polymerase II (RPB1), and translation elongation factor 1-α (TEF1) are used for inferring the existence of a new Clonostachys species from the Cerrado biome in Brazil, described here as C. chloroleuca. The species produces dimorphic, primary, and secondary conidiophores that form consistently greenish conidial masses on artificial media. It resembles therefore C. rosea f. catenulata although it differs from this species by less adpressed branches in the secondary conidiophores. The new species is also phylogenetically related to C. byssicola and C. rhizophaga. Our inventory suggests that C. byssicola, C. chloroleuca, C. pseudochroleuca, C. rhizophaga, C. rogersoniana, and C. rosea commonly occur in native and agriculturally used soils of the Cerrado and Amazon Forest. Using sequences available from two genome-sequenced strains employed as biological control agents, we confirm the identity of the European strain IK726 as C. rosea and identify strain 67-1 from China as C. chloroleuca.  相似文献   

2.
Most species of Tamarix originate in Eurasia and at least five species have become invasive around the world, including South Africa. However, T. usneoides is indigenous to southern Africa, where the potential for biological control of the invasive species is being investigated. Recent research on the invasive species is reviewed here with particular reference to these South African biocontrol efforts. The successful biological control programme against invasive Tamarix in the USA, using several species of “Tamarisk beetle”, is being used as a guide for the South African research. The South African programme is complicated by firstly, the presence of the indigenous T. usneoides which raises the precision of host-specificity required, and secondly, the introduced and indigenous Tamarix have a high intrinsic value for phytoremediation of mine tailings dams in South Africa. The phylogenetic proximity of these Tamarix species to each other has contributed to this challenge, which has nevertheless been successfully addressed by molecular techniques used to separate the species. In addition, classical morphological techniques have been used to separate the Tamarisk beetles, so that now they can generally be matched to Tamarix tree species. Overall, it is concluded that given the broad knowledge now available on the ecology and identity of both the trees and their biocontrol agents, the prospects for successful biological control of Tamarix in South Africa are good.  相似文献   

3.
Based on molecular evidence and morphological studies, the new polypores Antrodia multiformis and A. tenerifensis are described. Both species were discovered in arid biotope, A. multiformis in southwestern USA and A. tenerifensis in Tenerife (Canary Islands). Both of the new species show unique morphological and cultural features and are different in phylogeny. The structure of the Antrodia core clade of brown rot polypores is discussed.  相似文献   

4.
A rust fungus was found on the leaves of Euphorbia helioscopia during a field study in Pakistan. Previously, Melampsora euphorbiae, M. euphorbiae-gerardianae and M. helioscopiae have been reported on E. helioscopia, the first two of which are also known from Pakistan. Morphological observations of the newly collected rust samples detected some differences from the previously described Melampsora species on E. helioscopia. The molecular analysis of the ITS and LSU sequences also detected that the rust is different from the previously reported rusts described from E. helioscopia. Based on both morphological comparisons and sequence analysis, the rust is described here as M. pakistanica sp. nov. This species could have potential as a bio-control agent against its host plant—E. helioscopia—which is a weed of wheat fields in Pakistan and elsewhere in the world.  相似文献   

5.
Two ornamental plants of Althaea rosea Cav. and Malva crispa L. were exposed to various concentrations of lead (Pb) (0, 50, 100, 200 and 500 mg·kg?1) for 70 days to evaluate the accumulating potential and the tolerance characteristics. The results showed that both plant species grown normally under Pb stress, and A. rosea had a higher tolerance than M. crispa, while M. crispa had a higher ability in Pb accumulation than A. rosea. Besides, lower Pb concentration (50 mg·kg?1) stimulated the shoot biomass in both plant species. Pb accumulation in plants was consistent with the increase of Pb levels, and the main accumulation sites were the roots and the older leaves. In addition, the photosynthetic pigments content and chlorophyll fluorescence parameters were influenced by Pb stress. In such case, both of the plants could improve the activities of antioxidant enzymes of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX), and the contents of the total soluble sugar and soluble protein, which reached the highest value at Pb 100 mg·kg?1, as well as the accumulation of the total thiols (T-SH) and non-protein thiols (NP-SH) to adapt to Pb stress. Thus, it provides the theoretical basis and possibility for ornamental plants of A. rosea and M. crispa in phytoremediation of Pb contaminated areas.  相似文献   

6.
Species of Alnus (alders) have become invaders in several parts of the world. Here we report the presence of three naturalized alien species: A. glutinosa, A. incana and A. rubra from several populations in nature reserves of northwestern Patagonia, an area of remarkably high biodiversity. Alnus glutinosa had been cited previously for Chile and southern Argentina, but A. incana and A. rubra are here reported for the first time. As we found morphological variation within and among the populations of these introduced species that makes their discrimination difficult, we used chloroplast (trnH-psbA) and nuclear ribosomal (ITS) DNA sequences to confirm their identifications from morphological characteristics. Results from nuclear and chloroplast sequence data confirm the morphological tentative identification of the three species and remark the utility of molecular information together with morphology for the detection of introduced species of taxonomically difficult groups. The invasive characteristics of these alien tree species are discussed in relation to the conservation of the nature reserves where they are found.  相似文献   

7.
Cortinarius is one of the most species-rich genera of mushroom-forming fungi. Based on phylogenetic and morphological evidence, Cortinarius, sect. Riederi, is introduced at sectional level (= subsect. Riederi sensu Brandrud & Melot). The taxonomy, phylogeny, ecology and distribution of not only mainly European but also including some North American taxa of this section are treated, which includes nine species and two varieties. Of these, three taxa are described as new (C. burlinghamiae, C. pallidoriederi and C. argenteolilacinus var. dovrensis). The sect. Riederi species possess morphological features similar to Phlegmacium group(s) and forms a phylogenetically isolated lineage, with no supported affinity to other phlegmacioid groups. Three taxa are known from both Europe and North America, two species are known only from North America and five only from Europe. Altogether, eight of the ten taxa are associated with conifers or northern (boreal-subalpine) deciduous trees (Betula spp.). Only two species occur in more temperate forests (Fagus forests), and no species have so far been found in thermophilous Quercus forests  相似文献   

8.
Environmental sampling yielded two yeast species belonging to Microstromatales (Exobasidiomycetes, Ustilaginomycotina). The first species was collected from a leaf phylloplane infected by the rust fungus Coleosporium plumeriae, and represents a new species in the genus Jaminaea, for which the name Jaminaea rosea sp. nov. is proposed. The second species was isolated from air on 50% glucose media and is most similar to Microstroma phylloplanum. However, our phylogenetic analyses reveal that species currently placed in Microstroma are not monophyletic, and M. phylloplanum, M. juglandis and M. albiziae are not related to the type species of this genus, M. album. Thus, Pseudomicrostroma gen. nov. is proposed to accommodate the following species: P. glucosiphilum sp. nov., P. phylloplanum comb. nov. and P. juglandis comb. nov. We also propose Parajaminaea gen. nov. to accommodate P. albizii comb. nov. and P. phylloscopi sp. nov. based on phylogenetic analyses that show these are not congeneric with Jaminaea or Microstroma. In addition, we validate the genus Jaminaea, its respective species and two species of Sympodiomycopsis and provide a new combination, Microstroma bacarum comb. nov., for the anamorphic yeast Rhodotorula bacarum. Our results illustrate non-monophyly of Quambalariaceae and Microstromataceae as currently circumscribed. Taxonomy of Microstroma and the Microstromataceae is reviewed and discussed. Finally, analyses of all available small subunit rDNA sequences for Jaminaea species show that J. angkorensis is the only known species that possess a group I intron in this locus, once considered a potential feature indicating the basal placement of this genus in Microstromatales.  相似文献   

9.
Multilocus DNA sequence-based identification methods raised the number of known species assigned to the Aspergillus section Versicolores. Currently, there are 16 species accepted in the section, including A. amoenus, A. austroafricanus, A. creber, A. cvjetkovicii, A. fructus, A. griseoaurantiacus, A. hongkongensis, A. jensenii, A. protuberus, A. puulaauensis, A. subversicolor, A. sydowii, A. tabacinus, A. tennesseensis, A. venenatus, and A. versicolor. Based on morphological identifications, most of these species were identified as either A. sydowii or A. versicolor, with the latter reported to have a world-wide distribution, growing in many habitats. Aspergillus versicolor has been implicated in health hazards including sick building syndrome, human and animal mycoses, and contamination of food and feed were assigned primarily to this species. A. versicolor is still commonly isolated from indoor surveys, even though species such as A. jensenii and A. creber seem more common. From indoor air samples collected at a grain mill in Croatia, we isolated an undescribed species assigned to the Aspergillus section Versicolores. A polyphasic approach, including sequence-based methods, morphological and physiological studies, was used for species characterization and in this paper is described as Aspergillus pepii. Additionally, sterigmatocystin producing abilities have been confirmed. Based on a combined phylogenetic tree, morphological features and sterigmatocystin producing abilities, A. pepii is closely related to A. versicolor. Further studies should explore the frequency of the species in indoor environments and its medical, industrial, and environmental significance.  相似文献   

10.
We combined morphological and combined ITS, TUB and TEF sequence data to infer the phylogeny of the recently introduced genus Pseudopestalotiopsis. Two new species from China, Ps. camelliae from blighted leaves of Camellia sinensis and Ps. ignota from an undetermined host in China, are introduced with illustrated accounts and compared with similar taxa. Grey blight disease of tea appears to be caused by a group of fungi that constitutes a species complex. A new combination is proposed to emend the monophyly of Pseudopestalotiopsis and a species comparison is provided for taxa in the genus.  相似文献   

11.
An emerging insight in invasion biology is that intra-specific genetic variation, human usage, and introduction histories interact to shape genetic diversity and its distribution in populations of invasive species. We explore these aspects for the tree species Paraserianthes lophantha subsp. lophantha, a close relative of Australian wattles (genus Acacia). This species is native to Western Australia and is invasive in a number of regions globally. Using microsatellite genotype and DNA sequencing data, we show that native Western Australian populations of P. lophantha subsp. lophantha are geographically structured and are more diverse than introduced populations in Australia (New South Wales, South Australia, and Victoria), the Hawaiian Islands, Portugal, and South Africa. Introduced populations varied greatly in the amount of genetic diversity contained within them, from being low (e.g. Portugal) to high (e.g. Maui, Hawaiian Islands). Irrespective of provenance (native or introduced), all populations appeared to be highly inbred (F IS ranging from 0.55 to 0.8), probably due to selfing. Although introduced populations generally had lower genetic diversity than native populations, Bayesian clustering of microsatellites and phylogenetic diversity indicated that introduced populations comprise a diverse array of genotypes, most of which were also identified in Western Australia. The dissimilarity in the distribution and number of genotypes in introduced regions suggests that non-native populations originated from different native sources and that introduction events differed in propagule pressure.  相似文献   

12.
A multivariate morphometric study of the genus Nicoraepoa was carried out to examine patterns of morphological variation among the species and to identify additional characters to allow a clearer delimitation among species. Nicoraepoa is a taxonomically complex genus comprising seven species endemic to South America. Although most of the species are well delimited, two of them, N. andina and N. chonotica, are morphologically similar and very difficult to separate. The morphological variation among species, with overlapping morphological characters, pseudovivipary and possible hybridization make species boundaries unclear. In the present paper, sixty-seven characters were scored for a total of 216 specimens and analyzed using ordination, cluster and discriminant analyses. Based on multivariate results, we recognized species groups and morphological diagnostic characters that allow clearer species delimitation. As a result, N. chonotica has been transferred to N. andina as a subspecies that inhabit southern Patagonia. Other taxa could be recognized and delimited by diagnostic characters: N. erinacea, N. pugionifolia, N. stepparia, N. subenervis subsp. spegazziniana and N. subenervis subsp. subenervis. Moreover, we discuss the possibility that a new species from Bolivia, based on only one specimen, closely related to N. subenervis should be ascribed in Nicoraepoa.  相似文献   

13.
During a survey of fungicolous fungi, a novel taxon from the surface of stroma of an unidentified Xylaria species was collected. Phylogenetic analyses showed that this taxon clustered with Calcarisporium sp. and C. arbuscula isolates, but was resolved as a distinct species. A detailed morphological examination coupled with phylogenetic analysis indicated that the taxon represented a new species. Calcarisporium xylariicola sp. nov. is thus introduced. The new taxon is characterized by short conidiophores with swollen bases and less length/width ratio of conidia that distinguish it from other Calcarisporium species. Calcarisporium is presently placed in Hypocreales genera, incertae sedis genus. Species in the genus are largely fungicolous, or occasionally caulicolous or foliicolous, and have hyaline, erect, verticillate conidiophores and sympodial, polyblastic conidiation. A phylogenetic analysis of combined SSU, ITS, LSU, TEF and RPB2 sequence data from Calcarisporium species and other taxa in Hypocreales indicate that Calcarisporium is a distinct lineage from other families. Therefore, a new family, Calcarisporiaceae, in Hypocreales is introduced.  相似文献   

14.
The diversity of lignicolous freshwater fungi of the Greater Mekong Subregion are currently being studied. In this paper, 18 fresh collections of Pleurotheciaceae from submerged wood in freshwater are characterized based on morphological characters and analyses of ITS, LSU, SSU and RPB2 sequence data. Six new species of Pleurotheciella (P. aquatica, P. fusiformis, P. guttulata, P. lunata, P. saprophytica, P. submersa), one new Phaeoisaria species (Ph. aquatica) and one new Pleurothecium species (Pl. aquaticum) are introduced based on their distinct morphology and evidence from molecular phylogeny. Pleurotheciella uniseptata, Phaeoisaria clematidis and Pleurothecium pulneyense are also redescribed and phylogenetic relationships assessed herein, these species are the first records for China.  相似文献   

15.
Excavation of burrows by fiddler crabs (genus Uca) is an important component in mangrove ecosystem functioning. This bioturbation activity can be measured by analysing the burrow architecture of these crabs. The aim of the present study is to describe and evaluate inter specific differences in the burrow morphologies of four species of fiddler crabs (Uca rosea, Uca triangularis, Uca dussumieri and Uca vocans) using polyester resin casts of the burrows. For each of the species, sex and carapace width (CW; mm) were determined for all the individuals. Three burrow morphological characters viz. burrow diameter (BD; mm), total burrow depth (TBD; mm) and burrow volume (BV; cm3) were considered during the study. Density of each species throughout the year was also assessed. For all the species BD and BV were higher in case of males compared to the females and they showed significant positive correlation with the CW of the burrow inhabitants. The amount of sediment excavated by each crab was evaluated in terms of BV. Among all the studied species, U. rosea was established as the most potent bioturbative candidate in the studied mangrove due to their greater density and moderate ability to excavate burrow.  相似文献   

16.
Profilicollis chasmagnathi Holcman-Spector, Mañé-Garzón & Dei-Cas, 1977 (Acanthocephala: Polymorphidae) has been reported to parasitise different grapsid species as intermediate hosts along the South Atlantic shores, i.e. Cyrtograpsus angulatus (Dana) and Neohelice granulata (Dana) in Uruguay and Cyrtograpsus altimanus (Rathbun) in Argentina. Larvae of a similar acanthocephalan described as Profilicollis antarcticus Zdzitowiecki, 1985 were recorded in the crab Hemigrapsus crenulatus (Milne-Edwards) from an estuarine habitat on the Southeast Pacific shore in Chile. Earlier studies have questioned the specific assignation of the Chilean estuarine populations of Profilicollis Meyer, 1931. The aim of this study was to re-examine the identification of these acanthocephalans by means of morphological and molecular analyses of cystacanths of Profilicollis spp. gathered from C. angulatus, N. granulata, C. altimanus and H. crenulatus. Our analyses showed that a single species of Profilicollis, P. chasmagnathi, parasitises these four crab species. The assessment of specimens from the South Shetlands Islands, the type-locality of P. antarcticus, is needed before formally proposing that P. antarcticus is a junior subjective synonym of P. chasmagnathi.  相似文献   

17.
Massariothea is a coelomycetous genus that produces brown, distoseptate conidia with species commonly reported on grasses (Poaceae) worldwide. Two undescribed Massariothea species associated with grass hosts were collected in Thailand, Chiang Rai province. Phylogenetic analysis of ITS, LSU, and EF1-α sequence data revealed that the new taxa nested in the family Diaporthaceae. Massariothea thailandica and M. thysanolaenae are therefore introduced as novel species and compared with other Massariothea species. Detailed accounts of the morphological characters of the new species are provided with illustrations.  相似文献   

18.
19.
Bethencourtia Choisy ex Link is an endemic genus of the Canary Islands and comprises three species. Bethencourtia hermosae and Bethencourtia rupicola are restricted to La Gomera, while Bethencourtia palmensis is present in Tenerife and La Palma. Despite the morphological differences previously found between the species, there are still taxonomic incongruities in the group, with evident consequences for its monitoring and conservation. The objectives of this study were to define the species differentiation, perform population genetic analysis and propose conservation strategies for Bethencourtia. To achieve these objectives, we characterized 10 polymorphic SSR markers. Eleven natural populations (276 individuals) were analyzed (three for B. hermosae, five for B. rupicola and three for B. palmensis). The results obtained by AMOVA, PCoA and Bayesian analysis on STRUCTURE confirmed the evidence of well-structured groups corresponding to the three species. At the intra-specific level, B. hermosae and B. rupicola did not show a clear population structure, while B. palmensis was aggregated according to island of origin. This is consistent with self-incompatibility in the group and high gene flow within species. Overall, the genetic diversity of the three species was low, with expected heterozygosity values of 0.302 (B. hermosae), 0.382 (B. rupicola) and 0.454 (B. palmensis). Recent bottleneck events and a low number of individuals per population are probably the causes of the low genetic diversity. We consider that they are naturally rare species associated with specific habitats. The results given in this article will provide useful information to assist in conservation genetics programs for this endemic genus.  相似文献   

20.
Three Asian leaf beetles of the genus Chrysochus were investigated as potential biological control agents of Vincetoxicum rossicum and V. nigrum, invasive weeds in northeastern North America. Chrysochus chinensis and Ch. globicollis were collected from a field host in a different genus and subtribe. Preliminary no-choice laboratory tests with Ch. goniostoma showed that its physiological host range is too broad. Based on these data, we are not considering these three species as potential biological control agents of invasive Vincetoxicum species.  相似文献   

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