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1.
Cystotheca tjibodensis, formerly known as Lanomyces tjibodensis (Perisporiales), is a fungus found in 1920 in Indonesia. This species, hitherto only known from its type collection, is now regarded as belonging to the Erysiphales. However, molecular data are still required to verify the taxonomic affinity. In March 2011, we rediscovered this fungus at Cibodas Botanical Garden, Java. Detailed characterizations of this tropical powdery mildew are reported in this study based on morphological and molecular examinations. The anamorph of this species that was not found in the type specimen is also reported in this study.  相似文献   

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Takamatsu  Susumu  Sato  Yukio  Mimuro  Genki  Kom-un  Sawwanee 《Mycoscience》2003,44(3):165-171
 A new species of Erysiphe sect. Uncinula is described and illustrated from Japan. Erysiphe wadae sp. nov., found on Japanese beech (Fagus crenata, Fagaceae), is characterized by having two types of appendages, i.e., a long (true) appendage arising from the equatorial zone of the ascomata, and a short appendage arising from the upper part of the ascomata. This characteristic is shared by E. simulans, E. australiana, E. flexuosa, E. liquidambaris, E. prunastri, and E. togashiana. Erysiphe wadae differs from the latter five species in its brown-colored appendage. Erysiphe simulans is most similar to E. wadae, but differs in its loosely uncinate appendage and smaller number of ascospores. Identity of the nucleotide sequences of the rDNA ITS region is 92.3% between the two species. The significance of the two types of appendage in taxonomy and phylogeny of powdery mildews is discussed based on molecular phylogenetic analysis. Received: November 8, 2002 / Accepted: January 29, 2003 Acknowledgments We are grateful to Drs. Yukio Harada and Hideki Naito for help in collecting powdery mildew specimens; Dr. Uwe Braun for providing the specimen of E. flexuosa; and Mr. Tetsuya Hirata and Miss Sanae Matsuda for nucleotide sequences of E. togashiana and E. flexuosa. This work was partially supported by a Grant-in-Aid for Scientific Research (No. 13660047) from Ministry of Education, Culture, Sports, Science and Technology, Japan.  相似文献   

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Nanophyetiasis is the severe zoonotic disease caused by parasitic worms from the genus Nanophyetus. Humans and carnivorous animals become infected when they ingest raw fish containing metacercariae, especially Pacific salmonids. Nanophyetiasis is detected in limited geographical areas which include the coastal regions of the North Pacific: the United States of America, Russian Federation and Japan. Despite the epidemiological significance, Nanophyetus species have not been well studied genetically. In this research, we for the first time explored genetic diversity of Nanophyetus japonensis from Japan in comparison with those of related species, N. salmincola from North America and N. schikhobalowi from the Russian Far East, based on sequence variation in the nuclear ribosomal gene family (18S, ITS1–5.8S–ITS2 and 28S) and mitochondrial nad1 gene, encoding subunit I of the respiratory chain NADH dehydrogenase. The results confirmed the independent species status for the compared flukes, demonstrated a greater genetic similarity of Asian species between themselves than each of them with the North American one, suggesting that N. japonensis and N. schikhobalowi are close sister species, and also revealed discrepancy between the levels of morphological and genetic differentiation.  相似文献   

6.
甘草内生真菌的分离及鉴定   总被引:4,自引:0,他引:4  
植物体内普遍存在着内生菌,为了探寻传统药材甘草的质量与其内生菌之间可能存在的关系。对采自新疆的甘草根部进行了内生真菌的分离及鉴定。选用CYM真菌培养基,对其内生真菌进行分离及纯化,选择其中最占优势的两种菌落分别进行了菌落形态观察及菌丝形态(棉兰染色)观察,以及基因组DNA的18S rDNA和ITS rDNA序列鉴定和系统进化分析。本研究结果表明从甘草根部主要分离到两种内生真菌,分别属于Fusarium镰刀菌属和Gibberella赤霉菌属。  相似文献   

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Phyllactinia is a unique genus within the Erysiphales (Ascomycota) having a partly endo-parasitic nature of the mycelium within the host plant tissues. We constructed phylogenetic trees for the genus Phyllactinia and its allied genera based on a total of 120 nucleotide sequences of the 28S rDNA and ITS regions to discuss their phylogenetic relationships with special references to host plants, biogeography, evolutionary dating, and taxonomy. The analysis of the Erysiphales confirmed the monophyly of the endo-parasitic genera, i.e. Leveillula, Phyllactinia, and Pleochaeta. Phyllactinia specimens used in this study were divided into six distinctive groups and three subgroups. Interestingly, Leveillula, an obligately endo-parasitic genus of the Erysiphales, grouped together with Phyllactinia, although this was not significantly supported by the Kishino–Hasegawa and Shimodaira–Hasegawa tests. This suggests that the evolution within this group of fungi occurred from partial endo-parasitism to obligate endo-parasitism. The host range of Phyllactinia is mostly confined to woody plants, especially deciduous trees. Betulaceae, Fagaceae, Ulmaceae, Moraceae, and Rosaceae may have close connections to the divergence of the groups and subgroups of Phyllactinia concerned. Most of these plant families are known as major members of the boreotropical flora of the Tertiary, which suggests an early Tertiary origin of this genus. A comparison of the phylogenies of hosts and parasites revealed that host range expansion at higher taxonomic levels (higher than family level) is independent of the phylogeny of plants. Conversely, host range expansions in lower taxonomic levels (infrafamilial or infrageneric) tend to occur within a single family or genus. An estimation of the evolutionary timing using a molecular clock approach suggested that Phyllactinia split from Pleochaeta about 60 M years ago (Ma) in the early Tertiary and divergence of the six major clades of Phyllactinia occurred between 5 and 40 Ma during the Oligocene and Miocene. Divergence within the major clades and within Leveillula occurred maybe from more than 5 Ma onwards during the Pliocene and Quaternary. This is the first comprehensive phylogenetic study of Phyllactinia and other endo-parasitic genera of the Erysiphales.  相似文献   

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采用分子生物学和形态学相结合的方法,对采自广东省翁源县的编号为GDa71的昆虫病原线虫进行分类鉴定.该线虫各虫期的主要形态特征、测量值以及基于ITS1和部分28S rDNA两段序列,分别构建系统进化树均显示它与印度异小杆线虫Heterorhabditis indica相似,是后者的一个品系,为中国新纪录.  相似文献   

9.
时敏  陈学新  马云  何俊华 《昆虫学报》2007,50(2):153-164
本研究选取矛茧蜂亚科Doryctinae(昆虫纲Insecta:膜翅目Hymenoptera:茧蜂科Braconidae)的6族15属18种做内群,茧蜂科其它7亚科11属11种做外群,首次结合同源核糖体28S rDNA D2基因序列片段和100个形态学和解剖学特征对该亚科进行了系统发育学研究。利用“非圆口类"的小腹茧蜂亚科Microgastrinae为根,以PAUP*4.0和MrBayes 3.0B4软件分别应用最大简约法(MP)和贝叶斯法对矛茧蜂亚科的分子数据和分子数据与非分子数据的结合体进行了运算分析;并以PAUP*4.0对矛茧蜂亚科的28S rDNA D2基因序列片段的碱基组成与碱基替代情况进行了分析。结果表明:矛茧蜂亚科的28S rDNA D2基因序列片段的GC含量在39.33%~48.28%之间变动,而对于碱基替代情况来讲,矛茧蜂亚科各成员间序列变异位点上颠换(transversion)大于转换(transition)。不同的分析算法所产生的系统发育树都表明矛茧蜂亚科是一个界限分明的单系群;在矛茧蜂亚科内,除了吉丁茧蜂族Siragrini为单系群外,其他族(矛茧蜂族Doryctini和方头茧蜂族Hecabolini)都是并系群。对于矛茧蜂亚科内各属之间的相互亲缘关系,不同算法所得的系统发育树的拓扑结构不完全一致,表明矛茧蜂亚科内(属及族)的系统发育关系还有待于进一步研究。  相似文献   

10.
利用含罗丹明B的橄榄油检测平板从中国各省市油污土壤中分离、筛选产脂肪酶微生物菌株,扩增细菌的核糖体基因16S rDNA序列和真菌的ITS2序列,分析核糖体基因簇DNA,并结合形态学特征从而对产脂肪酶菌株进行分子生物学鉴定.核糖体基因16S rDNA序列分析及系统发育分析表明,分离得到的产脂肪酶细菌分别属于枯草芽孢杆菌(Bacillus subtilis)、产碱假单胞菌(Pseudomonas alcaligenes)、洋葱伯克霍尔德氏(Burkholderia cepacia)、琼氏不动杆菌(Acinetobater jurii)、嗜麦芽窄食单孢菌(Stenotrophomonas maltophilia)和荧光假单胞菌(Pseudomonas sp.);真菌核糖体基因转录间隔区(ITS2)序列及同源性分析表明产脂肪酶真菌分别属于黑曲酶(Aspergillus niger)、白地酶(Galactomyces geotrichum)、解脂耶氏酵母(Yarrowia lipolytica)、丝孢酵母(Trichosporon guehoae)和假丝酵母(Candida sp.).研究结果表明,核糖体基因簇的DNA分析技术为从自然界分离、鉴定产脂肪酶菌种提供了一种快速有效的手段,为产脂肪酶微生物资源开发利用奠定了技术基础.  相似文献   

11.
阮永明  刘树生 《昆虫学报》2005,48(6):859-865
烟粉虱体内存在共生细菌,包括初生共生细菌(primary endosymbiont)和次生共生细菌(secondary endosymbiont)。本项研究应用PCR技术检测了烟粉虱浙江B型和非B型China-ZHJ-1种群中共生细菌的分布。结果表明,烟粉虱B型和非B型体内均存在初生共生细菌,而两者次生共生细菌的组成存在差异。一种肠杆菌科次生共生细菌仅在B型烟粉虱中发现,而另两种次生共生细菌Wolbachia和杀雄菌Arsenophonus仅在非B型中发现。初生共生细菌的系统发育分析表明,B型是入侵生物型,而浙江非B型是本地生物型。  相似文献   

12.
During the DNA sequence analyses of specimens on Quercus subgenus Cyclobalanopsis deposited as Erysiphe gracilis or Cystotheca wrightii, some specimens exhibited DNA sequences that are different from the sequences of the two species. Based on BLAST search and morphological observations, the true causal agent was identified as E. quercicola. This is the first record of E. quercicola on species of subgenus Cyclobalanopsis. Previous studies revealed that E. quercicola is plurivorous infecting a wide range of tropical fruit trees and woody plants. Further studies are needed to address the question as to why only E. quercicola infect species of subgenus Cyclobalanopsis.  相似文献   

13.
Taxonomy within the sponge Order Haplosclerida remains somewhat contentious. Both morphology and biochemistry have been employed to help unravel the relationships of the Order with limited results perhaps because of the small number of reliable characters. We employed phylogenetic analysis of 750 base pairs of the 5′ end of the 28S rRNA gene to study relationships between 20 taxa within the Order. While preliminary (low number of taxa, one gene region) results suggested strong discrepancy to former phylogenies, there was no support for the monophyly of the Order and almost all morphologically defined genera appeared to be polyphyletic.  相似文献   

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Linkage analysis was used to determine the genetic map location of er-1, a recessive gene conditioning resistance to powdery mildew, on the Pisum sativum genome. Genetic linkage was demonstrated between er-1 and linkage group 6 markers after analyzing the progeny of two crosses, an F2 population and a set of recombinant inbred lines. The classes of genetic markers surrounding er-1 include RFLP, RAPD and allozyme markers as well as the morphological marker Gty. A RAPD marker tightly linked to er-1 was identified by bulked segregant analysis. After DNA sequence characterization, specific PCR primers were designed to convert this RAPD marker into a sequence characterized amplified region (SCAR).  相似文献   

16.
Litvaitis  M. K.  Newman  L. J. 《Hydrobiologia》2001,444(1-3):177-182
Systematic relationships within the cotylean family Pseudocerotidae were examined using nucleotide sequences of the D3 expansion segment of the 28S rDNA gene. A previously suggested separation of Pseudoceros and Pseudobiceros based on the number of male reproductive systems was confirmed. Regardless of the algorithm employed, Pseudoceros always formed a monophyletic clade. Pseudobiceros appeared to be paraphyletic; however, a constrained maximum parsimony tree was not significantly longer (2 steps, = 0.05). Additionally, the genera Maiazoon, Phrikoceros and Tytthosoceros were validated as taxonomic entities, and their relationships to other genera within the family were determined. Molecular data also supported species separations based on colour patterns. An intraspecific genetic distance of 1.14% was found for Pseudoceros bifurcus, whereas the intrageneric distance was 3.58%. Genetic distances among genera varied, with the closest distance being 2.048% between Pseudobiceros and Maiazoon, and the largest distance (8.345%) between Pseudoceros and Tytthosoceros.  相似文献   

17.
戴仁怀  陈学新  李子忠 《昆虫学报》2008,51(10):1055-1064
首次在国内利用28S rDNA D2区段和16S rDNA基因序列,结合50个形态特征对角顶叶蝉亚科(Deltocephalinae)[半翅目(Hemiptera): 叶蝉科(Cicadellidae)]19个属进行系统发育分析研究。从无水乙醇浸泡保存的标本中提取基因组DNA并扩增了19个内群和1种外群Typhlocybinae[半翅目(Hemiptera): 叶蝉科(Cicadellidae)]种类的28S rDNA D2基因片段并测序,同时扩增了16S rDNA基因片段并测序11条,采用了GenBank中1个种类的16S rDNA同源序列。采用PAUP*4.0和MrBayes3.0两个分析软件和3种建树方法,利用同源28S D2 rDNA和16S rDNA两个基因序列与形态特征结合进行系统发育分析研究。分析结果表明,二叉叶蝉族Macrostelini是一个单系,并在角顶叶蝉亚科的系统发育中处于基部的位置,是内群中最原始的族;角顶叶蝉族Deltocephalini中除了纹翅叶蝉属Nakaharanus,其余各属构成单系;殃叶蝉族Euscelini内属的归属比较混乱,可能是一个并系群,属间差异有待进一步研究。隆额叶蝉族Paralimnini与顶带叶蝉族Athysanini是姐妹群。带叶蝉属Scaphoideus与纹翅叶蝉属Nakaharanus是姐妹群,二者与木叶蝉属Phlogotettix的关系最近,三者构成一个单系,建议将三者归为带叶蝉族Scaphoideini。研究结果还表明,小眼叶蝉族Xestocephalini和Balcluthini的系统发育位置不明,有待进一步研究。  相似文献   

18.
Views on myxosporean phylogeny and systematics have recently undergone substantial changes resulting from analyses of SSU rDNA. Here, we further investigate the evolutionary trends within myxosporean lineages by using 35 new sequences of the LSU rDNA. We show a good agreement between the two rRNA genes and confirm the main phylogenetic split between the freshwater and marine lineages. The informative superiority of the LSU data is shown by an increase of the resolution, nodal supports and tree indexes in the LSU rDNA and combined analyses. We determine the most suitable part of LSU for the myxosporean phylogeny by comparing informative content in various regions of the LSU sequences. Based on this comparison, we propose the D5–3′-end part of the LSU rRNA gene as the most informative region which provides in concatenation with the complete SSU a well resolved and robust tree. To allow for simple amplification of the marker, we design specific primer set for this part of LSU rDNA.  相似文献   

19.
Phylogeny of the Platyhelminthes and the evolution of parasitism   总被引:4,自引:0,他引:4  
Robust phylogenies provide the basis for interpreting biological variation in the light of evolution. Homologous features provide phylogenetically informative characters whereas homoplasious characters provide phylogenetic noise. Both provide evolutionary signal. We have constructed molecular and morphologically based phylogenies of the phylum Platyhelminthes using a recently revised morphological character matrix and complete 18S and two partial 28S rRNA gene sequences in order to evaluate the emergence and subsequent divergence of parasitic forms. In total we examine 65 morphological characters, 97 18S rDNA, 41 Dl domain 28S rDNA, and 49 D3-D6 domain 28S rDNA sequences. For the molecular data there were 748, 132 and 249 phylogenetically informative sites for the 18S, Dl and D3-D6 28S rDNA data sets respectively. Morphological and molecular phylogenetic solutions are incongruent but not incompatible, and using the principles of conditional combination (18S rDNA + morphology passing Templeton's test) they demonstrate: a single and relatively early origin for the parasitic Neodermata (including the cestodes, trematodes and monogeneans); sister-group status between the cestodes and monogeneans, and between these taxa and the trematodes (digeneans and aspidogastreans). The sister-group to the Neodermata is likely to be a large clade of neoophoran turbellarians, based on combined evidence, or a clade consisting of the Fecampiid + Urastomid turbellarians, based on morphological evidence alone. The combined evidence solution for the phylogeny of fiatworms based on 18S rDNA and morphology is used to interpret morphological and life-history data and to support a model for the evolution and radiation of neodermatan parasites in the group.  相似文献   

20.
Detached mungbean (Vigna radiata L.Wilczek) leaves were inoculated with a conidial suspension of a local isolate (TI-1) of the powdery mildew pathogen (Erysiphe polygoni DC) under controlled environment conditions. Based on the latent period and severity of the infection, a rating scale of 0–5 was used to classify the host pathogen interactions. Reactions 0, 1 and 2 were considered resistant and referred to as R0, R1 and R2 while 3, 4 and 5 were classified as susceptible (S). RUM lines (resistant to powdery mildew) and their derivatives are crossed with several susceptible (reaction types 3–5) genotypes and the inheritance of the resistance was studied in the F1, F2 and F3 generations. The results showed that powdery mildew resistance in mungbean is governed by two dominant genes designated as Pm-1 and Pm-2. When both Pm-1 and Pm-2 were present, an R0 reaction was observed after inoculation with TI-1. The resistant reaction was R1 when only Pm-1 was present and R2 in the presence of Pm-2. In the absence of both Pm-1 and Pm-2, susceptible reactions 3, 4 and 5 were observed.  相似文献   

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