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Two morphologically similar groups of ascomycetes with globose to subglobose perithecia, elongate necks, unitunicate asci floating freely at maturity, and hyaline ascospores currently placed in Calosphaeria s. lat. and Ceratostomella s. lat., respectively, are studied. The Calosphaeria-like fungi have groups of perithecia growing between cortex and wood, arranged in circular groups with converging necks and piercing the cortex in a common point; the asci with a shallow apical ring and U- to horseshoe-shaped hyaline ascospores are compared with Calosphaeria pulchella, the type species of the genus. Conidiogenesis of the investigated Calosphaeria-like fungi is holoblastic-denticulate; ramichloridium-like and sporothrix-like conidiophores and conidia were formed in vitro. Ascospore and ascus morphology, structure of the ascal apex, ascogenous system, mode of conidiogenesis and the large subunit rRNA sequences of this group differ considerably from C. pulchella and both groups are unrelated. Thus a new genus, Tectonidula, is described with two accepted species, T. hippocrepida and T. fagi; they are separated by ascospore and ascus morphology and holoblastic-denticulate conidiogenesis from the core species of Calosphaeria. The placement of Tectonidula among perithecial ascomycetes is discussed. The relationship of Tectonidula with Barbatosphaeria and two ramichloridium-like hyphomycetous genera Rhodoveronaea and Myrmecridium is investigated. Three species formerly attributed to Ceratostomella are studied. The revision of the herbarium type specimen and fresh material of Ceratostomella ligneola revealed that it is conspecific with Ceratostomella ampullasca and Ceratostomella similis. The LSU phylogeny clearly separated C. ligneola from Ceratostomella s. str. and morphologically similar Lentomitella. On the basis of molecular sequence data and detailed comparison of morphology of asci, ascospores and ascogenous system the genus Natantiella is described for C. ligneola with C. ampullasca and C. similis as its synonyms. Natantiella produced sterile mycelium in vitro.  相似文献   

3.
Pseudocercospora cyatheae C. Nakash. & S. Inaba on Cyathea sp. as a new species is described. Three species belonging to the genus Cercospora and allied genera are newly added to the mycoflora of Japan. They are Cercospora armoraciae on Armoracia rusticana, Passalora passaloroides on Amorpha fruticosa, and Pseudocercospora nogalesii on Cytisus scoparius.  相似文献   

4.
Seven new calochroid and fulvoid species of Cortinarius   总被引:1,自引:0,他引:1  
We describe seven new European species of Cortinarius. All species are based on analyses of morphological and DNA sequence data. They all belong to a well-supported clade comprising most species traditionally treated in Cortinarius subgenus Phlegmacium sections Fulvi and Calochroi (i.e. the/Calochroi clade). All taxa are either fulvoid (containing anthraquinoid pigments) or calochroid (without these pigments). Morphological and ecological data are presented for all species and compared with similar species. A dichotomous key is presented for C. calochrous and similar species, including all six newly described calochroid species. The calochroid species C. albertii, C. chailluzii, C. cisticola, C. sancti-felicis, C. selandicus and C. vesterholtii spp. nov., and the fulvoid species C. langeorum sp. nov. are described.  相似文献   

5.
The teleomorph of Mycopappus quercus causing frosty mildew in Quercus acutissima is described as a new genus and species, Redheadia quercus, in the Sclerotiniaceae. Apothecia sprout from sclerotia on the fallen infected leaves kept for 10 months at 5°C and subsequent incubation at 15°C under diffused room light. Typical zonate lesions and multicellular propagules of M. quercus are produced on Q. acutissima, by mycelial inoculation using an isolate from a single ascospore, confirming the teleomorph–anamorphic connection. No significant differences are observed between cultured colonies of isolates from the ascospore and those from the propagule. Sclerotia and microconidia of the fungus are produced on culture media.  相似文献   

6.
郭林 《菌物学报》1995,14(Z1):163-168
本文报道炭黑粉菌一新种,即细叶蒿草炭黑粉菌(Anthracoidea filifoliae L. Guo sp.nov.)和4个我国新记录种:1)角孢炭黑粉菌(A. angulata(H. Sydow) Boidol & Poclt), 2)黍状苔炭黑粉菌(A. paniceae Kukkenen), 3)狼尾草团黑粉菌(Sorosporium penniseti Mundkur)和4)米勒粘孢黑粉菌(Tolyposporium muellerianum (Thuemen) McAlpine)。  相似文献   

7.
为探讨国产豆科(Leguminosae)鸡血藤属(Callerya Endl.)和崖豆藤属(Millettia Wight et Arn.)的属间和属下分类,在扫描电镜下观察了鸡血藤属11种5变种和崖豆藤属6种2变种的花粉形态。结果表明,鸡血藤属和崖豆藤属植物的花粉都是3孔沟或3沟的单粒,辐射对称,赤道面观主要为类球形或近扁球形,极面观主要为圆形或圆状三角形。鸡血藤属植物的花粉大小为中等,而崖豆藤属的为小型。两属植物花粉的沟膜呈现或多或少的隆起或凹陷,附有细微的或粗糙的颗粒,花粉外壁纹饰可分为6种类型。花粉形态不支持Schot合并所有灰毛鸡血藤复合体中除了亮叶鸡血藤[C.nitida(Benth.)R.Geesink]与喙果鸡血藤[C.cochinchinensis(F.P.Metcalf)Z.WeiPedley]为灰毛鸡血藤[C.cinerea(Benth.)Schot]的观点,花粉大小支持将鸡血藤属从广义崖豆藤属中分离。  相似文献   

8.
The morphology of an unarmored chain-forming harmful dinoflagellate Cochlodinium polykrikoides and its similar species such as Cochlodinium catenatum, Cochlodinium fulvescens, and Cochlodinium convolutum was carefully observed, emphasizing the single cell stage for clarifying taxonomically important morphological features. To differentiate C. polykrikoides from C. convolutum, the shape and the position of the nucleus are useful characters. C. polykrikoides also differs from C. fulvescens in being smaller in size, possessing many rod-shaped chloroplasts and having the sulcus running just below the cingulum on the dorsal surface. Careful observation of the ichnotype of C. catenatum suggests that C. catenatum sensu Kofoid and Swezy collected from off La Jolla, CA, USA, is not identical to C. catenatum sensu Okamura and is probably a different species, in having no chloroplasts and a nucleus positioned at the center of the cell. In addition, C. polykrikoides has many morphological features in common with C. catenatum sensu Okamura except for slightly elongate cells and is probably a junior synonym of this species.  相似文献   

9.
基于对标本和文献的比较研究,确认豆科香槐属(Cladrastis Raf.)中小叶香槐(C.parvifolia C.Y.Ma)、藤香槐(C.scandens C.Y.Ma)、秦氏香槐(C.chingii DuleyVincent)与本属分布最广的翅荚香槐[C.platycarpa(Maxim.)Makino]为同种植物。其中,小叶香槐被处理为翅荚香槐的一变种,即C.platycarpa var.parvifolia(C.Y.Ma)Z.Q.Song,D.X.XuS.J.Li,藤香槐与秦氏香槐被处理为翅荚香槐原变种的两个新异名。同时讨论了翅荚香槐的分类地位及其散布。  相似文献   

10.
Abundances and interactions among biological control insects and their effects on target invasive plants were monitored within the flower heads and roots of diffuse knapweed, Centaurea diffusa, and in spotted knapweed, Centaurea stoebe, along the Colorado Front Range. Flower weevils, (Larinus species) and root-feeders (Cyphocleonus achates and Sphenoptera jugoslavica) were released on knapweed that already supported biological control gall flies (Urophora species). At a single monitoring site, seed production by C. diffusa declined from 4400 seeds m−2 in 1997 to zero seeds m−2 on the monitoring sites in 2006, while the flowering stem density of C. diffusa declined from a peak of almost 30 stems m−2 in 2000 to zero stems m−2 in 2006. The average abundance of Urophora and Larinus in flower heads fluctuated independently during the 2001–2006 interval, while the relative abundance of C. achates and S. jugoslavica in roots exhibited a weak inverse relationship that appeared driven by climate effects. The relative abundance of insects on a population of C. stoebe was monitored for five years as Larinus species and C. achates became established on spotted knapweed that already supported Urophora species. Spotted knapweed seed production on our monitoring site declined from 4600 seeds m−2 in 2003 to zero seeds m−2 in 2006. Unlike C. diffusa, substantial numbers of rosettes of C. stoebe remained present. Larinus consumed almost all Urophora encountered in C. diffusa, and consumed about 40% of the Urophora in co-infested flower heads of C. stoebe (ca. 10–15% of the total Urophora population). No negative correlations between the relative densities of flower head and root-feeding insects were observed. The effects of these insects on target plants have produced results consistent with the ‘cumulative stress hypothesis’ for biological control of Centaurea species.  相似文献   

11.
【目的】研究大面积栽植外来树种日本落叶松和日本花柏对鄂西北森林群落物种多样性的影响,为评价外来树种的入侵风险提供依据。【方法】采用样地调查法对比研究外来树种日本落叶松和日本花柏人工林与当地森林群落特征差异。【结果】日本落叶松人工林样地林下植物种类丰富,样地平均物种数与当地天然林样地物种数相比无显著差异;林下灌木层和草本层多样性指数较高,草本层多样性指数与当地天然林相比无显著差异;林下未发现日本落叶松的更新苗。日本花柏人工林样地平均物种数显著少于当地其他人工林样地;乔木层、灌木层和草本层的4个多样性指数值均小于当地其他人工林样地;在3个样地中出现日本花柏更新苗,更新苗数量达479株·hm~(-2)。【结论】引种栽培日本落叶松不会导致当地森林群落的物种多样性降低,不会引起生物入侵风险;但引种栽培日本花柏会明显降低当地森林群落的物种多样性,对当地森林生态系统的稳定构成一定威胁。  相似文献   

12.
通过野外调查、标本查阅及文献考证,订正了华南吊灯花属(Ceropegia Linn.)植物,将狭瓣吊灯花(C. angustilimba Merr.)从吊灯花(C. trichantha Hemsl.)的异名中予以恢复,提供了二者的形态描述,确认华南地区记录的柳叶吊灯花(C. salicifolia H. Huber)实为剑叶吊灯花(C. dolichophylla Schltr.)的错误鉴定,并提供了后者的形态描述。  相似文献   

13.
Penicillium roqueforti, P. crustosum and P. paneum grow on ensiled grain and recycled feed unless properly treated. The former two species occur also on cut lumber in Canada. These are known to produce a number of secondary metabolites including roquefortine. In cooler dairy production areas, including Scandinavia and North America, cattle toxicosis has been associated with silage contaminated by these fungi. We collected strains associated with cow or cattle toxicoses. The principal metabolites were determined making use of a new extraction method and analysis combining HPLC, LC/MS/MS, and LC/NMR. Penicillium roqueforti and P. crustosum required amino acid nitrogen for metabolite formation and their toxins were formed under conditions of low oxygen (20–30% saturation). Production of roquefortine C occurred on depletion of the available nitrogen and penitrem A on depletion of carbon source. Yield was reduced by excess carbon. Medium osmotic tension (aw) affected metabolite production by the two species differently. Penicillium paneum was associated with ill-thrift of dairy cows and P. roqueforti was associated with more serious symptoms. Our data suggest a physiological basis for the common occurrence of roquefortine C in silage without serious consequences and the alternative, the presence of roquefortine C and toxicoses. The strain isolated from lumber was the best producer of the toxins studied. This is the first report of the toxigenic potential of P. roqueforti and P. paneum from Canada.  相似文献   

14.
Isolates belonging to an undescribed Phytophthora species were frequently recovered during an oak forest soil survey of Phytophthora species in eastern and north-central USA in 2004. The species was isolated using an oak leaf baiting method from rhizosphere soil samples collected from Quercus rubra, Q. macrocarpa, and Q. phellos. This species is formally described as P. quercetorum. It is homothallic and has aplerotic oogonia and paragynous antheridia. It produces papillate sporangia (occasionally bipapillate) of ovoid-elongated shapes. Its temperature optimum for growth is ca 22.5 °C with the upper limit of ca 32.5 °C. P. quercetorum differs from the morphologically related P. quercina in producing distinct submerged colony-patterns, different growth-temperature requirements, and oogonial shapes and sizes. Phylogenetic analyses using seven nuclear loci supported P. quercetorum as a novel species within clade 4, closely related to P. arecae, P. palmivora, P. megakarya, and P. quercina.  相似文献   

15.
扩增了西施舌日照、连云港、北海、漳州4个野生群体、四角蛤蜊和中国蛤蜊各1个群体共73个样本的NAD5基因片段,测序获得了480bp核苷酸序列,分析核苷酸的多态性,旨在评估福建漳州西施舌与日照、连云港、北海西施舌之间的分化水平。结果:从73个序列中共检测到44种单倍型(Hap),其中西施舌4个群体有29种Haps,四角蛤蜊和中国蛤蜊分别有10种和5种Haps,漳州群体与北海、日照、连云港群体单倍型有明显差异;将西施舌分为北海、日照、连云港组(GP1)和漳州组(GP2)2个组,分析核苷酸差异,GP1与GP2间的T、A、G含量差异极显著(P0.01)。GP1与GP2间的遗传距离与组内(GP1、GP2)遗传距离之比为25.1—41.8,四角蛤蜊与中国蛤蜊之间的遗传距离与种内个体间遗传距离之比为24.4—36.7,GP1、GP2间的差异达到了四角蛤蜊和中国蛤蜊种间差异水平,而日照、北海群体间的遗传距离只有0.009,北海与日照群体地理位置虽远,但遗传差异则很小;AMOVA分析显示漳州西施舌发生了极显著遗传分化(FST=0.966—0.978,P0.01)。  相似文献   

16.
A new sanguinicolid trematode, Cardicola aurata sp. n., is described from gilthead seabream Sparus aurata L., from off the Spanish Mediterranean coast. The morphology of C. aurata sp. n. generally agrees with the diagnosis of the genus, however, in contrast to all other reported Cardicola spp. the male pore is located sub-medially at the posterior end of the body instead of sinistrally before the posterior end of the body. Based on a comparison of the morphology as well as partial 28S and ITS2 rDNA sequence data from the present species with that from closely related species, it was decided to emend the diagnosis of Cardicola rather than create a new genus, as the aberrant position of the male pore is likely to be an autapomorphy. The phylogenetic analyses revealed a close relationship between Cardicola and Paradeontacylix, two genera with considerable morphological differences; C. aurata sp. n. occupies a position intermediate to these genera. Thus, a morphological comparison of Cardicola, Paradeontacylix and Braya, a genus which is morphologically similar to Cardicola but clusters basal to the Cardicola/Paradeontacylix clade, was conducted. The results of this comparison showed that despite large differences with regard to body shape, the organisation of the internal organs is very similar in species of Cardicola and Paradeontacylix. The synopsis of morphological data and molecular phylogeny allows for interpretations regarding the importance of different morphological features for the phylogenetic inference of the Sanguinicolidae.  相似文献   

17.
Aphidophagous ladybird beetles (Coleoptera: Coccinellidae) are attracted to and feed heavily on aphids, but many species will also feed opportunistically on other prey that they encounter. In potatoes (Solanum tuberosum L.) in Washington State, USA, coccinellids feed on both green peach aphids (“GPA,” Myzus persicae Sulzer) and eggs of the Colorado potato beetle (“CPB,” Leptinotarsa decemlineata Say). The guild of aphidophagous ladybirds includes two native species, Hippodamia convergens Guérin-Méneville and Coccinella transversoguttata Brown. Recently, an introduced species, Coccinella septempunctata L., has invaded and apparently displaced its native congener. A second exotic, Harmonia axyridis Pallas, has colonized the area and is becoming more abundant. We compared larval development of each species on a monotypic diet of GPA, a monotypic diet of CPB eggs, or a mixed diet of both GPA and CPB eggs. Our goal was to answer two questions: (1) do larvae of the four ladybird species benefit from including CPB eggs in their diet and (2) do the four ladybird species differ in their ability to utilize CPB eggs as prey? No larva of any species completed development on a pure diet of CPB eggs, and survivorship was highest for all species when they fed on a pure diet of GPA. One native species, H. convergens, and one exotic species, H. axyridis, exhibited significantly lower survivorship on a mixed diet of both CPB eggs and GPA, compared to a pure GPA diet; H. axyridis also took longer to develop from egg to adult when both prey were provided. Survivorship of the two Coccinella spp. was not altered by the inclusion of CPB eggs with GPA, although CPB eggs lengthened the development time of C. transversoguttata. Adult size was not consistently affected by diet for any of the coccinellids. Overall, no ladybird species benefited from the inclusion of potato beetle eggs in its diet. The two Coccinella species responded similarly to the inclusion of CPB eggs, and so we would not expect any difference in the success of coccinellid larval development in potato fields following the replacement of C. transversoguttata by C. septempunctata. Hippodamia convergens and H. axyridis, the two species whose survivorship was depressed by combining CPB egg and aphid prey, were also the two species that consumed the greatest number of CPB eggs during successful larval development. A comparison of total egg consumption by each species cohort suggested that displacement of the other species by H. axyridis would not alter CPB biological control, because the higher per capita feeding rate by H. axyridis larvae compensated for individuals’ greater mortality risk on a diet including CPB eggs.  相似文献   

18.
Development rates were determined for three pteromalid parasitoids of houseflies under constant and varying temperatures from 15 to 35°C.Muscidifurax raptorGirault and Sanders was the fastest developing species, with females completing development in 13.8 days at 32.5°C and 66.5 days at 15°C.Spalangia geminaBoucek females completed development in 20.8 days at 30.0°C and 161 days at 15.0°C, whereasS. cameroniPerkins females completed development in 20.6 days at 30.0°C and 155.5 days at 15.0°C. Male development times were 90.3% of those for femaleS. geminaand 92.7 and 88.6% of those for femaleS. cameroniandM. raptor,respectively. Parasitoid survival was very low at 35°C for all species and noSpalangiasurvived constant exposure to 15.0°C. Exposure to these lethal temperatures for shorter periods indicated that the parasitoids can tolerate them well under conditions more typical of the field. Development rates were modeled using biophysical and degree-day models and the models were tested for their ability to predict development under fluctuating conditions (24–36°C). Neither model was superior for all three species because of interspecific differences in the parasitoids' responses to high temperatures. Agreement between predicted and observed development times for all three species was achieved by small empirical adjustments of a key parameter in the biophysical model.  相似文献   

19.
Taenia tapeworms of Finnish and Swedish wolves (Canis lupus) and Finnish brown bears (Ursus arctos), and muscle cysticerci of Svalbard reindeer (Rangifer tarandus platyrhynchus), Alaskan Grant's caribou (Rangifer tarandus granti) and Alaskan moose (Alces americanus) were identified on the basis of the nucleotide sequence of a 396 bp region of the mitochondrial cytochrome c oxidase subunit 1 gene. Two species were found from wolves: Taenia hydatigena and Taenia krabbei. The cysticerci of reindeer, caribou and one moose also represented T. krabbei. Most of the cysticercal specimens from Alaskan moose, however, belonged to an unknown T. krabbei-like species, which had been reported previously from Eurasian elks (Alces alces) from Finland. Strobilate stages from two bears belonged to this species as well. The present results suggest that this novel Taenia sp. has a Holarctic distribution and uses Alces spp. as intermediate and ursids as final hosts.  相似文献   

20.
Invasive, non-native, white grubs (Coleoptera: Scarabaeidae) cause significant damage in urban landscapes. Although the lack of natural enemies in their new home is often suggested as an important factor in the establishment and spread of invasive species, the potential of incumbent generalist parasites and pathogens to delay their establishment and spread has not been explored. We compared the susceptibility of the introduced Popillia japonica and the native Cyclocephala borealis to 16 species and strains of entomopathogenic nematodes isolated from within or outside the geographic ranges of the two scarabs. We found large variation in the virulence of the species/strains of nematodes with over 50% mortality of P. japonica produced by Heterorhabditis zealandica strain X1 and H. bacteriophora strain GPS11 and of C. borealis by H. zealandica and H. bacteriophora strains KMD10 and NC1. Heterorhabditis indica and H. marelatus caused less than 20% mortality of both scarab species. When considered as a group the nematode species and strains from within and outside the geographic ranges of either P. japonica or C. borealis did not differ in virulence towards either scarab species. Dose response studies with selected nematode species and strains against P. japonica and two additional non-native species Anomala (Exomala) orientalis and Rhizotrogus majalis and the native C. borealis indicated that R. majalis was the least susceptible and P. japonica and A. orientalis were as susceptible as the native C. borealis. Heterorhabditis zealandica was significantly more virulent than any other species or strain against P. japonica with a LC50 of 272 IJs/grub. The LC30 and LC50 values for H. zealandica were also the lowest among the four nematode species/strains tested against A. orientalis and C. borealis. The LC50 values for H. zealandica and H. megidis (UK strain) were significantly lower for the native C. borealis than the introduced A. orientalis. H. zealandica also showed the highest penetration efficiency and the lowest encapsulation in P. japonica and C. borealis grubs. Results suggest that the introduction of the exotic H. zealandica into the front-line states with respect to the movement of P. japonica and A. orientalis should be explored as a tactic to delay their establishment and spread. The results also suggest that the manipulation of the indigenous H. bacteriophora populations may help in delaying spread and mitigating losses caused by the invasive grub species.  相似文献   

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