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1.
This study evaluated how the proportional area of natural habitat surrounding a vineyard (i.e. landscape diversity) worked in conjunction with crop vigor, cultivar and rootstock selection to influence biological control of the western grape leafhopper (Erythroneura elegantula Osborn). The key natural enemies of E. elegantula are Anagrus erythroneurae S. Trjapitzin & Chiappini and A. daanei Triapitsyn, both of which are likely impacted by changes in landscape diversity due to their reliance on non-crop habitat to successfully overwinter. Additionally, E. elegantula is sensitive to changes in host plant quality which may influence densities on specific cultivars, rootstocks and/or vines with increased vigor. From 2010–2013, data were collected on natural enemy and leafhopper densities, pest parasitism rates and vine vigor from multiple vineyards that represented a continuum of landscape diversity. Early in the season, vineyards in more diverse landscapes had higher Anagrus spp. densities and lower E. elegantula densities, which led to increased parasitism of E. elegantula. Although late season densities of E. elegantula tended to be lower in vineyards with higher early season parasitism rates and lower total petiole nitrogen content, they were also affected by rootstock and cultivar. While diverse landscapes can support higher natural enemy populations, which can lead to increased biological control, leafhopper densities also appear to be mediated by cultivar, rootstock and vine vigor.  相似文献   

2.
Seven new late Middle Cambrian (Cedaria-Crepicephalus zone) acrotretid species are described from the Great Basin, USA. The species belong to five genera of which Lensotreta is new. The following new species are described: Anabolotreta? glabra, Anabolotreta mogota, Canthylotreta crista, Dactylotreta elegantula, Lensotreta perplexa, Opisthotreta transversa, and Opisthotreta indistincta. The shell structure of Canthylotreta is described for the first time based on new material of the type species Canthylotreta marjumensis and of the new species C. crista. The shell of Canthylotreta includes two types of shell fabric, camerate and columnar. Moreover, parts of the shell show transitional textures, supporting the view that the camerate shell structure may has originated from a columnar fabric. Picnotreta lophocracenta Robson and Pratt, 2001, recently described from western Newfoundland, is also described from the new occurrence in the Great Basin.  相似文献   

3.
A bacterial strain, designated M26T, was isolated from a fish gastrointestinal tract, collected from Zhanjiang Port, South China. 16S rRNA gene sequence analysis indicated that strain M26T belongs to the subclass α-Proteobacteria, being related to the genus Paracoccus, and sharing highest sequence similarity with Paracoccus alcaliphilus JCM 7364T (98.1 %), Paracoccus huijuniae FLN-7T (97.3 %), Paracoccus stylophorae KTW-16T (97.1 %) and Paracoccus seriniphilus DSM 14827T (96.9 %). The major quinone was determined to be ubiquinone Q-10, with Q-9 and Q-8 as minor components. The major fatty acid was identified as C18:1ω7c, with smaller amounts of C18:0 and C16:0. The G+C content of the genomic DNA was determined to be 64.3 mol%. The DNA hybridization value between strain M26T and the most closely related type strain, P. alcaliphilus, was 29.0 ± 1.0 %. The results of physiological and biochemical tests and low DNA–DNA relatedness showed that the strain could be readily distinguished from closely related species. On the basis of these phenotypic and genotypic data, strain M26T is concluded to represent a novel species of the genus Paracoccus, for which the name Paracoccus siganidrum sp. nov. is proposed. The type strain is M26T (=CCTCC AB 2012865T = DSM 26381T).  相似文献   

4.
A molecular taxonomic study on the north European species of the genus Agathomyia Verrall (Diptera: Platypezidae) is presented. We include molecular phylogenetic analyses based on two fragments of the mtDNA COI and a fragment of the nuclear 28S rDNA genes for both adult and immature stages of Agathomyia spp. The Agathomyia elegantula (Zetterstedt) group taxa were revised based on the newly obtained molecular and morphological data. Two new species belonging to the A. elegantula group were described, Agathomyia alneti Ståhls & Rättel sp.n. and A. shatalkini Ståhls sp.n. Agathomyia boreella (Zetterstedt) and A. scutellaris (Zetterstedt) were resurrected from synonymy of A. elegantula Zetterstedt. The genus Antrodiella Ryvarden & I.Johans was recorded as fungal host for Agathomyia elegantula group species and is a new host fungus genus for Platypezidae and for genus Agathomyia. Antrodiella faginea and A. pallescens were recorded as host fungi for A. boreella, A. pallescens for A. elegantula and A. serpula for A. alneti sp.n. We present identification keys to males and to all hitherto known third‐stage larvae of north European Agathomyia species including digital images, and discuss conservation aspects for these taxa.  相似文献   

5.
Paul Sartenaer 《Geobios》1979,12(4):535-547
The genus CalvinariaStainbrook, 1945 is beingsubdivided by the writer into the following two new genera: Plionoptycherhynchus n. gen. based on the type species P. exformosus n. gen., n. sp., and Lateralatirostrum n. gen. based on the type species L. athabascense (Kindle, 1924).These type species are proposed as indices ofzones in the upper part of the lower Frasnian stage.The writer wishes to point out the doubtful validity of palaeogeographic reconstructions undertaken on the basis of too comprehensively, and consequently poorly, defined genera. In this connection he points out that the form occuring in the Ardennes and attributed to Eifelian species Terebratula formosaSchnur, 1851 belongs actually to a different genus and species and is of a different age.  相似文献   

6.
Aquilegia elegantula Greene and A. caerulea James occur in montane and subalpine habitats in the southern Rocky Mountains of western North America. The red and yellow flowers of A. elegantula are nodding, odorless, protogynous, and secrete a concentrated (44%) sucrose nectar in the floral spurs. Seed set in flowers under pollinator exclosures was 12% while seed set in open-pollinated flowers was 65%. The flowers of A. elegantula are pollinated primarily by the Broad-tailed Hummingbird (Selasphorus platycercus [Swainson]) and by at least three species of pollen-foraging bumblebees, of which Bombus occidentalis Greene is the most common. The blue and white flowers of A. caerulea are erect, mildly fragrant, protandrous, and secrete a 26% sucrose nectar. Seed set in caged flowers in the field averaged 39%. in uncaged flowers 54%. The most important pollinators of A. caerulea are the crepuscular hawkmoth, Hyles (=Celerio) lineata (Fabricius) and ten species of pollen-foraging Bombus. The most abundant bumblebee species, B. occidentalis, is also a frequent nectar thief. Differences in pollination systems alone probably do not constitute an effective anti-hydridization mechanism between A. elegantula and A. caerulea, but do serve to reinforce differences in habitat and flowering time that distinguish the two species.  相似文献   

7.
Pungency in Capsicum spp. is an important quality trait for pepper breeding. The perception of pungency in pepper is due to the presence of a group of compounds named capsaicinoids, only found within the Capsicum genus. How pungency is controlled at genetic and molecular levels has not been completely elucidated. The use of molecular markers to assess pungency trait is required for molecular breeding, despite the difficulty of development of universal markers for this trait. In this work, a DNA sequence possibly related to pungency with a high similarity to Pun1 locus was studied, and sequence analysis of this homolog revealed a 15?bp deletion in non-pungent pepper accessions. An allele-specific pair of primers was designed and specific fragments of 479?bp from non-pungent and 494?bp from pungent accessions were obtained. Polymorphism of this marker, named MAP1, was tested in a wide range of accessions, belonging to several Capsicum species, including pungent and non-pungent accessions of C. annuum L., and pungent accessions of C. chinense, C. baccatum, C. frutescens, C. pubescens, C. galapagoense, C. eximium, C. tovarii, C. cardenasii, and C. chacoense. All these Capsicum accessions were correctly discriminated. The marker suitability to assess pungency in domesticated and wild Capsicum species was demonstrated, and therefore it will be very useful in marker assisted selection (MAS). Moreover, MAP1 was located in a saturated pepper linkage map and its possible relationship with the Pun1 locus has been discussed. Among the available markers for this complex quality trait, the marker developed in this study is the most universal so far.  相似文献   

8.
We describe the species Metschnikowia bowlesiae sp. nov. based on the recovery of six isolates from Hawaii and Belize. The species belongs to the Metschnikowia arizonensis subclade of the large-spored Metschnikowia clade. The isolates are haploid and heterothallic. Both Hawaiian strains had the mating type h + and the Belizean strains were h ?. Paraphyletic species structures observed in some ribosomal DNA sequence analyses suggest that M. bowlesiae sp. nov. might represent an intermediate stage in a succession of peripatric speciation events from Metschnikowia dekortorum to Metschnikowia similis and might even hybridize with these species. The type of M. bowlesiae sp. nov. is strain UWOPS 04-243x5 (CBS 12940T, NRRL Y-63671) and the allotype is strain UWOPS 12-619.1 (CBS 12939A, NRRL Y-63670).  相似文献   

9.
We examined the toxicity of a fungicide, sulfur, to the egg parasitoid Anagrus erythroneurae (Hymenoptera: Mymaridae) Trjapitsyn and Chiapini and the vineyard leafhopper pest Erythroneura elegantula Osborn (Homoptera: Cicadellidae) and tested whether or not the use of sulfur in the field affects biological control of E. elegantula. Using field cage bioassays, we demonstrated that sulfur is toxic to adult A. erythroneurae parasitoids, but not toxic to adult E. elegantula leafhoppers. We nonetheless found in a field experiment that sulfur produced no changes in rates of parasitism or E. elegantula egg density, and generated only a very small increase in the density of E. elegantula nymphs. These results suggest that sulfur, although toxic to A. erythroneurae, is not highly disruptive of E. elegantula biological control in vineyards. Our results suggest that simple bioassays of acute toxicity may not accurately predict the impact of agricultural chemicals on biological control.  相似文献   

10.
11.
Michelia tonkinensis A. Chev.这个名称在发表时未指定模式,曾被处理为M. balansae (Aug. DC.) Dandy的异名。在查阅了其原白和原始材料后,确认采自越南北部Tuyen Quang省的标本——Fleury 37.667 (P)是该种唯一的原始材料,应该作为模式看待,同时确认Michelia tonkinensis是一独立的种,不应该处理为M. balansae的异名。此外,还提供了M. tonkinensis的异名、俗名、描述、分布及查阅的标本等综合信息。  相似文献   

12.
Trichostomum obtusifolium P. Beauv. is lectotypified and the type material is briefly described and illustrated. It is shown that the species correctly belongs within the genus Anomodon Hook. & Tayl., not Racomitrium Brid., and it is synonymous with A. minor (Hedw.) Lindb. A brief nomenclatural note on A. minor is presented and its homotypic synonyms are listed.  相似文献   

13.
《Comptes Rendus Palevol》2016,15(5):489-500
A new stem dugongid species, Prototherium ausetanum sp. nov. (Dugongidae, Halitheriinae), is described based on a cranium from the middle Eocene of Mas Vilageliu (Tona, NE Iberian Peninsula). The new species displays a combination of features that enables its distinction from other halitheriines, including Prototherium veronense (type species of the genus), Prototherium? intermedium (which likely belongs to a different genus), and Prototherium? montserratense (here considered a nomen dubium), as well as Eotheroides spp. In overall morphology (e.g., dolichocephaly) the new species more closely resembles species previously included in Prototherium. However, a cladistic analysis based on craniodental features recovers the new species as the sister taxon of Eotheroides aegyptiacum (type species of this genus), further constituting a polytomy with P. veronense, Eotheroides lambondrano and the remaining Halitheriinae. Our analysis further indicates that P.? intermedium is more derived than other species of Prototherium, but it does not conclusively resolve the phylogenetic relationships between the included species of Prototherium and Eotheroides. A deeper taxonomic revision of these two genera would be required in order to better resolve the phylogeny of early dugongids.  相似文献   

14.
《Mycological Research》2006,110(5):521-526
The molecular phylogeny of Acarosporaceae with a focus on the recently proposed genus Polysporinopsis was investigated using maximum parsimony and Bayesian analyses, using nuITS-LSU and mtSSU rDNA sequence datasets. A well-supported monophyletic clade corresponding to Acarospora (including the type species A. schleicheri, A. fuscata, A. nitrophila, A. rugulosa, A. bullata, A. sinopica, A molybdina and A. peliscypha) was present in all analyses. Acarospora as currently delimited is not monophyletic; neither A. smaragdula nor A. badiofusca belongs to the genus in the restricted sense. Polysporinopsis, which comprises three species previously classified in Acarospora (P. sinopica-type species, P. smaragdula, and P. rugulosa) is not a monophyletic group separate from Acarospora s. str. Acarospora sinopica and A. smaragdula are not closely related; A. sinopica belongs to Acarospora s. str., but A. smaragdula is one of the most basal taxa currently known in Acarosporaceae.  相似文献   

15.
《Comptes Rendus Palevol》2018,17(6):366-377
A new Plio-Pleistocene viverrid species is described based on two newly discovered maxillae (KW 10141 and KW 10383) from the recent excavations at the hominin-bearing site of Kromdraai (Gauteng, South Africa). This major site allows us to address the conundrum of Paranthropus and Homo origins in South Africa and presents a highly diverse carnivore spectrum (at least 22 species) including herpestids and viverrids. Civettictis braini nov. sp. is a viverrid species comparable in size to the extant African civet Civettictis civetta (Schreber, 1776). However C. braini nov. sp. differs significantly from the extant species in its dental proportions. Its canine and three premolars (P1–P3) are relatively robust, while its carnassials (P4) and two molars (M1, M2) are extremely reduced. This new species supplements our knowledge on carnivore taxonomic diversity and paleoecology in Southern Africa about 2 millions of years ago.  相似文献   

16.
Peter H. Kerr 《ZooKeys》2014,(386):29-83
Megophthalmidia Dziedzicki is a small leiine genus (Mycetophilidae) with seven species described from the Neotropics and ten species from the Palearctic region. Two species of Megophthalmidia have been reported for North America. Recent collecting of Mycetophilidae in California and Arizona, however, shows current North American diversity of Megophthalmidia is at least on par to other regions of the world. Eight new species of Megophthalmidia are described here, increasing the number of Nearctic Megophthalmidia species to nine. Included is a particularly atypical member of the genus, M. saskia sp. n., which expands the genus concept of Megophthalmidia. Of the two species previously recorded for North America, only one actually belongs in the genus. Megophthalmidia occidentalis Johannsen, is fully described and illustrated. The other named species, M. marceda (Sherman) is illustrated and transferred to the genus Ectrepesthoneura Enderlein. A lectotype is designated for this species. A key to the species of Megophthalmidia of North America is provided. The biology of these flies is not yet known. Three of the new Megophthalmidia species – M. lenimenta, M. misericordia, and M. radiata – are only known to occur within small protected areas within the California State Park and UC Natural Reserve systems.  相似文献   

17.

Background

The Mycobacterium tuberculosis complex (MTC) comprises closely related species responsible for strictly human and zoonotic tuberculosis. Accurate species determination is useful for the identification of outbreaks and epidemiological links. Mycobacterium africanum and Mycobacterium canettii are typically restricted to Africa and M. bovis is a re-emerging pathogen. Identification of these species is difficult and expensive.

Methodology/Principal Findings

The Exact Tandem Repeat D (ETR-D; alias Mycobacterial Interspersed Repetitive Unit 4) was sequenced in MTC species type strains and 110 clinical isolates, in parallel to reference polyphasic identification based on phenotype profiling and sequencing of pncA, oxyR, hsp65, gyrB genes and the major polymorphism tandem repeat. Inclusion of M. tuberculosis isolates in the expanding, antibiotic-resistant Beijing clone was determined by Rv0927c gene sequencing. The ETR-D (780-bp) sequence unambiguously identified MTC species type strain except M. pinnipedii and M. microti thanks to six single nucleotide polymorphisms, variable numbers (1–7 copies) of the tandem repeat and two deletions/insertions. The ETR-D sequencing agreed with phenotypic identification in 107/110 clinical isolates and with reference polyphasic molecular identification in all isolates, comprising 98 M. tuberculosis, 5 M. bovis BCG type, 5 M. canettii, and 2 M. africanum. For M. tuberculosis isolates, the ETR-D sequence was not significantly associated with the Beijing clone.

Conclusions/Significance

ETR-D sequencing allowed accurate, single-step identification of the MTC at the species level. It circumvented the current expensive, time-consuming polyphasic approach. It could be used to depict epidemiology of zoonotic and human tuberculosis, especially in African countries where several MTC species are emerging.  相似文献   

18.
The Myrobalan plum, Prunus cerasifera, bears a complete-spectrum resistance to the root-knot nematodes (RKN) Meloidogyne spp. in comparison to the main resistance sources in Amygdalus rootstocks that have more restricted spectra, as evidenced by a differential resistance test based on the predominant species M. arenaria, M. incognita and M. javanica and the population M. sp. Floride. Resistance to M. arenaria (A) in Myrobalan plum is controlled by the Ma major resistance genes that are completely dominant and confer a non-host behaviour that totally prevents the multiplication of the nematode. The inheritance of resistance of this self-incompatible species to M. incognita (I), M. javanica (J) and the population M. sp. Floride (F), considered as belonging to a new RKN species, was studied using G1 hybrids from a diallel cross based on five parents, the two resistant P.2175 (Ma1 gene; heterozygous) and P.1079 (Ma2 gene; homozygous) and three host parents, P.2032, P.2646 and P.16.5 (recessive for both genes), completed with the G2 backcrosses P.16.5×(P.2646×P.1079), P.2646 ×(P.16.5×P.1079) and P.2175×(P.2646×P.1079). G1 and G2 clones obtained from softwood cuttings sampled from trees in the field experimental design, rooted in the nursery, and inoculated in containers (six replicates per clone) under greenhouse conditions, were simultaneously evaluated for their host suitability to two to four of the RKN species, based on a 0–5 gall index (GI) rating under a high and durable inoculum pressure of the nematode, and then classified into resistant (R; GI?0.2) or host (H; GI?1.3) classes. The resistance classification of each individual clone, evaluated to two (A/J: 319 clones), three (A/J/I: 249 clones) and four (A/J/I/F: 161 clones) RKN species, from segregating and non-segregating crosses involving either Ma1 or Ma2 or both or none, was identical whatever the species. The independence of the R/H classification from the tested RKN indicates that the Ma1 and Ma2 genes control resistance to all of them, and it is assumed that these genes also control resistance to other minor RKN species. The relationship of the Ma genes with the putative genes involved in Amygdalus sources is discussed with the objective of introducing them into new interspecific rootstocks expressing a complete-spectrum and high-level resistance.  相似文献   

19.
We describe Mentzelia canyonensis, a new species endemic to the Grand Canyon. Based on floral and fruit forms, shoot system architecture, and phylogenetic analyses of nuclear ribosomal DNA, we infer that M. canyonensis belongs to the ‘subshrubby’ clade of Mentzelia section Bartonia, which includes the morphologically similar M. hualapaiensis, M. oreophila, M. puberula, and M. tiehmii. The new species is most similar to M. hualapaiensis, which is also known only from the Grand Canyon. These two species share leaf shape, subshrubby habits, corolla color, and fruit shape, although they differ in staminode presence and especially in leaf and corolla size. Principal component analyses of variation among floral and vegetative traits demonstrates that M. canyonensis and M. hualapaiensis share highly overlapping floral character space, but M. canyonensis occupies unique vegetative character space compared to similar species. A dichotomous key is provided to assist with identification of, and differentiation among, species of Mentzelia section Bartonia that occur in the Grand Canyon region.  相似文献   

20.
Mycobacterium vaccae is a rapidly growing, nontuberculous Mycobacterium species that is generally not considered a human pathogen and is of major pharmaceutical interest as an immunotherapeutic agent. We report here the annotated genome sequence of the M. vaccae type strain, ATCC 25954.  相似文献   

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