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1.
The loci of the 5S and 45S rRNA genes were localized on chromosomes in five species of Capsicum, namely, an-nuum, chacoense, frutescens, baccatum, and chinense by FISH. The 5S rDNA was localized to the distal region of one chromosome in all species observed. The number of 45S rDNA
loci varied among species; one in annuum, two in chacoense, frutescens, and chinense, and four in baccatum, with the exceptions that ‘CM334’ of annuum had three loci and ‘tabasco’ of frutescens had one locus. ‘CM334’-derived BAC clones, 384B09 and 365P05, were screened with 5S rDNA as a probe, and BACs 278M03 and
262A23 were screened with 25S rDNA as a probe. Both ends of these BAC clones were sequenced. FISH with these BAC probes on
pachytenes from ‘CM334’ plant showed one 5S rDNA locus and three 45S rDNA loci, consistent with the patterns on the somatic
chromosomes. The 5S rDNA probe was also applied on extended DNA fibers to reveal that its coverage measured as long as 0.439
Mb in the pepper genome. FISH techniques applied on somatic and meiotic chromosomes and fibers have been established for chili
to provide valuable information about the copy number variation of 45S rDNA and the actual physical size of the 5S rDNA in
chili. 相似文献
2.
Two new species of the rare nematode family Creagrocercidae from earthworms are described and illustrated. Creagrocercus braziliensis n. sp. is distinguished from the type-species, C. barbatus Baylis, 1943, by: the presence of four cephalic papillae (vs a pair of finger-shaped latero-ventral processes) on the head; larger amphids; a more posterior excretory pore position;
a shorter pharynx which is remarkably expanded at the base; the nerve-ring situated just posterior to the base of the pharynx
(vs at mid-pharyngeal level); an anal aperture present in the females; anterior ovary and testis reach just into the anterior
half of the body (vs closely posterior to the pharynx); equal, similar (vs unequal, dissimilar) spicules; and a prominent, unpaired precloacal papilla in males. Creagrocercus drawidae n. sp. is related to C. barbatus by a similar pharyngeal shape and the presence of a tail ‘hook’, and to C. braziliensis n. sp. by: the lack of finger-shaped processes on the head and the presence of four cephalic papillae; a similar position
of the excretory pore; a similar arrangement and length of the reproductive system; the presence of unpaired precloacal papilla
in males; similar, almost equal spicules; and the presence of a tail ‘hook’. From both of these species C. drawidae differs by having: a much shorter body and pharynx; larger amphids; a more posterior nerve-ring position; larger and less
numerous eggs; greatly inflated (vs flat) vulval lips; shorter spicules; and a smaller caudal ‘hook’. For C. drawidae, the partial sequences of the SSU (18S) rDNA and the D2D3 segment of LSU (28S) rDNA were obtained and subjected to phylogenetic
analyses. The phylogenetic affiliations of the Creagrocercidae are discussed. 相似文献
3.
Megumi Igarashi Yoshie Abe Yoshimichi Hatsuyama Takanori Ueda Tomoko Fukasawa-Akada Tomoyuki Kon Tsuyoshi Kudo Takashi Sato Masahiko Suzuki 《Molecular breeding : new strategies in plant improvement》2008,22(1):95-118
Two apple genetic linkage maps were constructed using amplified fragment length polymorphisms (AFLPs), simple sequence repeats
(SSRs), random amplified polymorphic DNAs (RAPDs), and expressed sequence tag (EST)-derived markers in combination with a
pseudo-testcross mapping strategy in which the cultivars ‘Ralls Janet’ and ‘Delicious’ were used as the respective seed parents.
Mitsubakaido (Malus sieboldii) was used as the pollen parent for each of the segregating F1 populations. Expressed sequence tag data were obtained from the random sequencing of cDNA libraries constructed from in vitro
cultured shoots and maturing fruits of cv ‘Fuji’, which is the offspring of a cross between ‘Ralls Janet’ and ‘Delicious’.
In addition, a number of published gene sequences were used to develop markers for mapping. The ‘Ralls Janet’ map consisted
of 346 markers (178 AFLPs, 95 RAPDs, 54 SSRs, 18 ESTs, and the S locus) in 17 linkage groups, with a total length of 1082 cM, while that of ‘Delicious’ comprised 300 markers (120 AFLPs,
81 RAPDs, 64 SSRs, 32 ESTs, and the S, Rf, and MdACS-1 loci) on 17 linkage groups spanning 1031 cM. These maps are amenable to comparisons with previously published maps of ‘Fiesta’
and ‘Discovery’ (Liebhard et al., Mol Breed 10:217–241, 2002; Liebhard et al., Theor Appl Genet 106:1497–1508, 2003a) because several of the SSRs (one to three markers per linkage group) were used in all of the maps. Distorted marker segregation
was observed in three and two regions of the ‘Ralls Janet’ and ‘Delicious’ maps, respectively. These regions were localized
in different parts of the genome from those in previously reported apple linkage maps. This marker distortion may be dependent
on the combinations of cultivars used for map construction. 相似文献
4.
Wellyzar Sjamsuridzal Yoshito Tajiri Hiromi Nishida Ta Bich Thuan Hiroko Kawasaki Aiko Hirata Akira Yokota Junta Sugiyama 《Mycoscience》1997,38(3):267-280
To study the phylogeny and evolution of archiascomycetes, we determined the full sequence of the nuclear 18S rRNA gene from
14Taphrina species and 2Protomyces species, and the partial sequence ofSchizosaccharomyces japonicus var.japonicus. The sequences were phylogenetically analyzed by the neighbor-joining, maximum parsimony, and maximum-likelihood methods.
We also looked at their principal phenotypic characters and genotypic character. Relationships within the Ascomycota are concordant
with the previously published phylogenies inferred from 18S rDNA sequence divergence and divide the archi-, hemi-and euascomycetes
into distinct major lineages. All the trees show that, within the archiascomycete lineage, 11 of the 14Taphrina species and the 2Protomyces species are monophyletic. A core groups ofTaphrina andProtomyces is always monophyletic. The evidence from molecular and phenotypic characters such as cell wall sugar composition, ubiquinone,
cell wall ultrastructure, and mode of conidium ontogeny, strongly suggests that ‘T’. californica CBS 374.39, ‘T’. maculans CBS 427.69 and ‘T’. farlowii CBS 376.39 should be excluded from the archiascomycete lineage. ‘Taphrina’ farlowii CBS 376.39 groups withCandida albicans in the Saccharomycetales, whereas ‘T’. californica CBS 374.39 and ‘T’. maculans CBS 427.69 have a basidiomycete affinity and group with Tremellalean members in the hymenomycete lineage.Schizosaccharomyces is monophyletic. The strictly anamorphic yeastSaitoella complicata groups with the apothecial ascomyceteNeolecta vitellina rather than theTaphrina/Protomyces branch. 相似文献
5.
Ming-Min Lee Mathieu Sicard Marjorie Skeie S. Patricia Stock 《Systematic parasitology》2009,72(2):127-141
A new entomopathogenic nematode, Steinernema boemarei n. sp., is described from southern France. Morphological, molecular (28S and ITS rDNA sequence data) and cross-hybridisation
studies were used for diagnostics and identification purposes. Both molecular and morphological data indicate that the new
species belongs to the ‘glaseri-group’ of Steinernema spp. Key morphological diagnostic traits for S. boemarei n. sp. include the presence of prominent deirids (cervical papillae) on adult males, the morphology of the spicules and gubernaculum,
and the arrangement of the 23 genital papillae of the first generation males. Additionally, morphometric traits of the third-stage
infective juvenile, including total body length (mean 1,103 μm), tail length (mean 86 μm), location of the excretory pore
(mean 91 μm), and D% (mean 63), E% (mean 106) and H% (mean 41) values are definitive. In addition to these morphological characters,
analysis of both 28S and ITS rDNA sequences depict this Steinernema species as a distinct and unique entity. 相似文献
6.
Zhi Wei Wang Li Jun Zhang Jie Chen Chang Ping Xiang Shi Yong Mei Yuan Zhou Ting Wang 《Molecular breeding : new strategies in plant improvement》2010,25(2):339-349
In this work, we have identified a chimeric pentatricopeptide repeat (PPR)-encoding gene cosegregating with the fertility
restorer phenotype for cytoplasmic male sterility (CMS) in radish. We have constructed a CMS-Rf system consisting of sterile line ‘9802A2’, maintainer line ‘9802B2’ and restorer line ‘2007H’. F2 segregating population analysis indicated that male fertility is restored by a single dominant gene in the CMS-Rf system described above. A PPR gene named Rfoc was found in the restorer line ‘2007H’. It cosegregated with the fertility restorer in the F2 segregating population which is composed of 613 fertile plants and 187 sterile plants. The Rfoc gene encodes a predicted protein 687 amino acids in length, comprising 16 PPR domains and with a putative mitochondrial targeting
signal. Sequence alignment showed that recombination between the 5′ region of Rfob (EU163282) and the 3′ region of PPR24 (AY285675) resulted in Rfoc, indicating a recent unequal crossing-over event between Rfo and PPR24 loci at a distance of 5.5 kb. The sterile line ‘9802A2’ contains the rfob gene. In the F2 population, Rfoc and rfob were observed to fit a segregation ratio 1:2:1 showing that Rfoc was allelic to Rfo. Previously we have reported that a fertile line ‘2006H’, which carries the recessive rfob gene, is able to restore the male fertility of CMS line ‘9802A1’ (Wang et al. in Theor Appl Genet 117:313–320, 2008). However, here when conducting a cross between the fertile line ‘2006H’ and CMS line ‘9802A2, the resulting plants were
male sterile, which shows that sterile line ‘9802A2’ possesses a different nuclear background compared to ‘9802A1’. Based
on these results, the genetic model of fertility restoration for radish CMS is also discussed. 相似文献
7.
Xingguo Zhang Chaozhi Ma Tingdong Fu Yuanyuan Li Tonghua Wang Qingfang Chen Jinxing Tu Jinxiong Shen 《Molecular breeding : new strategies in plant improvement》2008,21(3):305-315
‘SI1300’ is a self-incompatible Brassica napus line generated by introgressing an S haplotype from B. rapa ‘Xishuibai’ into a rapeseed cultivar ‘Huayou No. 1’. Five S-locus specific primer pairs were employed to develop cleaved amplified polymorphic sequences (CAPS) markers linked the S haplotype of ‘SI1300’. Two segregating populations (F2 and BC1) from the cross between ‘SI1300’ and self-compatible European spring cultivar ‘Defender’, were generated to verify the molecular
markers. CAPS analysis revealed no desirable polymorphism between self-incompatible and self-compatible plants. Twenty primer
pairs were designed based on the homology-based candidate gene method, and six dominant sequence characterized amplified region
(SCAR) markers linked with the S-locus were developed. Of the six markers, three were derived from the SRK and SP11 alleles of class II B. rapa
S haplotypes and linked with S haplotype of ‘SI1300’. The other three markers were designed from the SLG-A10 and co-segregated with S haplotype of ‘Defender’. We successfully combined two pairs of them and characterized two multiplex PCR markers which could
discriminate the homozygous and heterozygous genotypes. These markers were further validated in 24 F3 and 22 BC1F2 lines of ‘SI1300 × Defender’ and another two segregating populations from the cross ‘SI1300 × Yu No. 9’. Nucleotide sequences
of fragments linked with S-locus of ‘SI1300’ showed 99% identity to B. rapa class II S-60 haplotype, and fragments from ‘Defender’ were 97% and 94% identical to SLG and SRK of B. rapa class I S-47 haplotype, respectively. ‘SI1300’ was considered to carry two class II S haplotypes and the S haplotype on the A-genome derived from B. rapa ‘Xishuibai’ determines the SI phenotype, while ‘Defender’ carry a class I S haplotype derived from B. rapa and a class II S haplotype from B. oleracea. SCAR markers developed in this study will be helpful for improving SI lines and accelerating marker-assisted selection process
in rapeseed SI hybrid breeding program. 相似文献
8.
Maria M. van Dyk Mogamat Khashief Soeker Iwan F. Labuschagne David Jasper G. Rees 《Tree Genetics & Genomes》2010,6(3):489-502
In the Western Cape region of South Africa, dormancy release and the onset of growth does not occur normally in apple (Malus x domestica Borkh.) trees during spring due to the mild winter conditions experienced and fluctuations in temperatures experienced during
and between winters. In this region, the application of chemicals to induce the release of dormancy forms part of standard
orchard management. Increasing awareness of the environmental impact of chemical sprays and global warming has led to the
demand for new apple cultivars better adapted to local climatic conditions. We report the construction of framework genetic
maps in two F1 crosses using the low chilling cultivar ‘Anna’ as common male parent and the higher chill requiring cultivars
‘Golden Delicious’ and ‘Sharpe’s Early’ as female parents. The maps were constructed using 320 simple sequence repeats, including
116 new markers developed from expressed sequence tags. These maps were used to identify quantitative trait loci (QTL) for
time of initial vegetative budbreak (IVB), a dormancy related characteristic. Time of IVB was assessed four times over a 6-year
period in ‘Golden Delicious’ x ‘Anna’ seedlings kept in seedling bags under shade in the nursery. The trait was assessed for
3 years on adult full-sib trees derived from a cross between ‘Sharpe’s Early’ and ‘Anna’ as well as for 3 years on replicates
of these seedlings obtained by clonal propagation onto rootstocks. A single major QTL for time of IVB was identified on linkage
group (LG) 9. This QTL remained consistent in different genetic backgrounds and at different developmental stages. The QTL
may co-localize with a QTL for leaf break identified on LG 3 by Conner et al. (1998), a LG that was, after the implementation of transferable microsatellite markers, shown to be homologous to the LG now known
to be LG 9 (Kenis and Keulemans 2004). These results contribute towards a better understanding regarding the genetic control of IVB in apple and will also be
used to elucidate the genetic basis of other dormancy related traits such as time of initial reproductive budbreak and number
of vegetative and reproductive budbreak. 相似文献
9.
Paula M. Leddy Timothy D. Paine Thomas S. Bellows Jr. 《Entomologia Experimentalis et Applicata》1993,68(1):43-50
The relationship between ovipositional preference ofSiphoninus phillyreae (Haliday) (Homoptera: Aleyrodidae) and host plant suitability on seven host plant species (Citrus sinensis (L.) cv. ‘Washington’ [navel orange],Fraxinus uhdei (Wenz.) [shamel ash],Heteromeles arbutifolia Roemer [toyon],Malus domestica Mill. cv. ‘Granny Smith’, [apple],Pistacia vera L. cv. ‘Kerman’ [pistachio],Prunus persica (L.) cv. ‘O’Henry’ [peach], andPyrus communis L. cv. ‘Bartlett’ [pear]) was evaluated. Ovipositional preference ofS. phillyreae was determined by measuring egg density after adult female whitefies were given a simultaneous choice of all host plants
for oviposition. Immature survival, developmental time, and adult size were examined to determine host plant suitability forS. phillyreae. All studies were performed under greenhouse conditions.S. phillyreae showed distinct ovipositional preference among host plant species. Host plant species had a significant effect on immature
survival, but little or no effect on developmental time or forewing length. For four of the seven host plant species tested,
there was an association between ovipositional preference and survival. 相似文献
10.
Gerard Muyzer Andreas Teske Carl O. Wirsen Holger W. Jannasch 《Archives of microbiology》1995,164(3):165-172
Denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rDNA fragments was used to explore the genetic diversity
of hydrothermal vent microbial communities, specifically to determine the importance of sulfur-oxidizing bacteria therein.
DGGE analysis of two different hydrothermal vent samples revealed one PCR band for one sample and three PCR bands for the
other sample, which probably correspond to the dominant bacterial populations in these communities. Three of the four 16S
rDNA fragments were sequenced. By comparison with 16S rRNA sequences of the Ribosomal Database Project, two of the DGGE-separated
fragments were assigned to the genusThiomicrospira. To identify these ‘phylotypes’ in more detail, a phylogenetic framework was created by determining the nearly complete 16S
rRNA gene sequence (approx. 1500 nucleotides) from three describedThiomicrospira species, viz.,Tms. crunogena, Tms. pelophila, Tms. denitrificans, and from a new isolate,Thiomicrospira sp. strain MA2-6. AllThiomicrospira species exceptTms. denitrificans formed a monophyletic group within the gamma subdivision of the Proteobacteria.Tms. denitrificans was assigned as a member of the epsilon subdivision and was distantly affiliated withThiovulum, another sulfur-oxidizing bacterium. Sequences of two dominant 16S rDNA fragments obtained by DGGE analysis fell into the
gamma subdivisionThiomicrospira. The sequence of one fragment was in all comparable positions identical to the 16S rRNA sequence ofTms. crunogena. Identifying a dominant molecular isolate asTms. crunogena indicates that this species is a dominant community member of hydrothermal vent sites. Another ‘phylotype’ represented a
newThiomicrospira species, phylogenetically in an intermediate position betweenTms. crunogena andTms. pelophila. The third ‘phylotype’ was identified as aDesulfovibrio, indicating that sulfate-reducing bacteria, as sources of sulfide, may complement sulfur- and sulfide-oxidizing bacteria
ecologically in these sulfide-producing hydrothermal vents. 相似文献
11.
Han-liang Chang 《Biosemiotics》2009,2(2):169-179
Like other sciences, biosemiotics also has its time-honoured archive, consisting of writings by those who have been invented
and revered as ancestors of the discipline. One such example is Jakob von Uexküll. As to the people who ‘invented’ him, they
are either, to paraphrase a French cliché, ‘agents du cosmopolitisme sémiotique’ like Thomas Sebeok, or de jure and de facto progenitor like Thure von Uexküll. In the archive is the special issue of Semiotica 42. 1 (1982) edited by the late Sebeok and introduced by Thure von Uexküll. It is in the opening essay that Thure von UexküIl tries to
restore Jakob von Uexküll’s role as a precursor of semiotics by negotiating the Elder with Saussure and the linguistics-oriented
‘semiology’ in his wake. However, semiotic mapping, in the strictly ‘disciplinary’ sense, of Jakob von Uexküll is no easy
task because he ‘knew neither Peirce nor Saussure and did not use their terminology’ (Thure von Uexküll 1982,2). Because Thure prefers to call the Elder’s science ‘general semiotics’ (Thure von Uexküll 1982), this paper begins by assessing Thure von Uexküll’s semiotic configuration of Jakob, probe into the force and limits of
the linguistic analogy, revisit the already time-honoured debate on the primary and secondary modelling systems, which was
made famous by the Moscow-Tartu semioticians in the early 1970s, but severely criticized by Sebeok and his followers. The
paper engages Sebeok from several fronts, directed first at his relegation of the Saussurian linguistic model, then at his
critique of the Primary Modelling System, and finally at his reservation about evolutionism in light of the current debate
on gene/meme co-evolution.
Paper presented at the Eighth Annual International Gatherings in Biosemiotics
University of the Aegean, Syros, Greece, 23–28 June 2008 相似文献
12.
13.
Summary Callus was initiated from in vitro-grown plants of Gladiolus cultivars ‘Jenny Lee’ and ‘Florida Flame.’ The age of callus used for regeneration of plants was either 9 mo. old or 8 yr
old from ‘Jenny Lee,’ and 4 mo. old from ‘Florida Flame.’ Regeneration medium consisted of Murashige and Skoog’s basal salts
medium supplemented with 2.0 mg/l (9.3 μM) kinetin. This medium was supplemented with various concentrations of either bialaphos (Meiji Seika, Tokyo, Japan) or phosphinothricin
(Hoechst-Roussell, Frankfurt, Germany). Bialaphos was more effective than phosphinothricin at stimulating plant regeneration.
Plants regenerated from 8-yr-old callus of ‘Jenny Lee’ only when the regeneration medium was supplemented with 0.10 mg/l bialaphos.
A bialaphos concentration of 0.01 mg/l stimulated regeneration from 9-mo.-old callus of cultivar ‘Jenny Lee’ and 4-mo.-old
callus of ‘Florida Flame.’ 相似文献
14.
Richard L. Bell Ralph Scorza Delores Lomberk 《Plant Cell, Tissue and Organ Culture》2012,108(2):229-236
Adventitious shoot regeneration of twenty-four pear genotypes was compared in a common in vitro shoot induction and development
protocol. This study also compared cultures newly established from scionwood with cultures that been in long-term cold storage.
In vitro cultures of 13 Pyrus genotypes and budwood from 23 Pyrus genotypes were obtained from the National Clonal Germplasm Repository (NCGR) in Corvallis, Oregon. With the exception of
one genotype of P. elaeagrifolia Pall., and ‘Ya Li’ (P. pyrifolia var. sinensis Teng & Tanabe), all were P. communis L. cultivars. The basal shoot induction media consisted of Chevreau and Leblay (CL) basal nutrients, vitamins, and organics
(Chevreau and Leblay in Acta Hortic 336: 263–268, 1993). The analysis of variance indicated that differences among genotypes were highly significant and the main effect of culture
origin was non-significant. However, there was a significant interaction between genotype and culture origin, with percentage
regeneration of ‘Abate Fetel’ from new budwood significantly greater than that from long-term in vitro cultures, while ‘Jesinji
Vodenac’ cultures derived from the old NCGR cultures regenerated significantly more adventitious shoots. The ranges of mean
regeneration frequency were similar for both in vitro (0–87.7%) and scionwood-derived cultures (0–70.7%). Maximum regeneration
was observed for ‘Conference’, followed by ‘Magness’, ‘Dr. Jules Guyot’, and Packham’s Triumph’. The range of number of adventitious
shoots was relatively narrow, with the minimum of 1.0 for seven genotypes to 2.2 for ‘Conference’. 相似文献
15.
Monica Santa-Maria Kenneth V. Pecota Craig G. Yencho George Allen Bryon Sosinski 《Plant Cell, Tissue and Organ Culture》2009,97(1):109-117
Sweetpotato (Ipomoea batatas L.) is an important crop in North Carolina with annual production of 0.33 million tons, accounting for 37% of total US supply
(USDA, Louisiana Farm Reporter 8(12), August 2008). To target industrial use, novel high-starch industrial-type varieties that contain more than 30% dry matter were developed
by conventional breeding methods. In vitro cultures from selected genotypes were established using meristem culture. To establish
regeneration procedures that could be coupled with transformation experiments, conditions for the induction of rapid shoot-organogenesis
in leaf explants were compared using varying concentrations of the auxins ‘NAA’, ‘IAA’, ‘2,4-D’, and ‘4-FA’ either alone or
in combination with zeatin riboside. Regeneration efficiencies, defined as the number of explants developing shoots out of
the total number tested, were as high as 57% for the best genotypes, with a significant genotype-dependent response observed
in all the hormone regimes evaluated. In all treatments, shoot regeneration was observed within 2 months. Our results led
to the establishment of optimized in vitro regeneration procedures for the novel high-starch sweetpotato (SP) genotypes ‘DM01-158’,
‘FTA94’, ‘FT489’, and ‘PDM P4’ that are rapid and reliable. 相似文献
16.
Daniela Lopes Paim Pinto Ana Maria Rocha de Almeida Mailson Monteiro Rêgo Maurecilne Lemes da Silva Evelyn Jardim de Oliveira Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2011,107(3):521-530
Mature zygotic embryos of three genotypes of Passiflora edulis Sims, including ‘FB-100’, ‘FB-200’, and ‘FB-300’ were incubated on a Murashige and Skoog (MS) (1962) medium supplemented with different concentrations (18.1–114.8 μM) of 2,4-diclorophenoxyacetic acid (2,4-D) and 4.4 μM of
6-benzyladenine (BA). MS basal medium and MS with BA induced germination of P. edulis embryos. The highest frequencies of embryogenic calli were observed when explants were incubated on MS medium supplemented
with 72.4 μM 2,4-D and 4.4 μM BA for ‘FB-200’, which showed the highest potential for embryogenic callus formation. Cytological
and histological analyses of pro-embryogenic callus revealed two distinct cell types: thin-walled, small, isodiametric cells
with large nuclei and dense cytoplasm, typical of intense metabolic activity; and elongated and vacuolated cells, with small
nuclei and less dense cytoplasm. Differentiation of somatic embryos was promoted on MS medium supplemented with activated
charcoal and indole-3-acetyl-l-aspartic acid (IAA-Asp) either with or without 2,4-D. However, no conversion of somatic embryos into plantlets was observed. 相似文献
17.
Specimens of the greasy grouper Epinephelus tauvina (Forssk?l), caught off Moorea, French Polynesia, harboured four species of gill monogeneans. The diplectanid Pseudorhabdosynochus pai n. sp. is characterised by an extremely big male quadriloculate organ (inner length 77 μm, cone length 15, tube length 47),
the largest of all members of the genus, and a sclerotised vagina with a very complex structure, including three secondary
chambers instead of one as in most species. Pseudorhabdosynochus sp. is a species of the ‘cupatus group’; this species is not formally described but various measurements are provided. The
ancyrocephalid Haliotrema sp. and the capsalid Benedenia sp. were rare; they are both mentioned but not described. The diplectanid fauna of E. tauvina corresponds to the pattern already found in a clade of grouper species, the members of which often harbour both a species
of the ‘cupatus group’ and another species of Pseudorhabdosynochus Yamaguti, 1958.
Résumé Des spécimens du mérou Epinephelus tauvina (Forssk?l) pêchés à Moorea, Polynésie Fran?aise, hébergeaient quatre espèces de monogènes sur les branchies. Le Diplectanidae Pseudorhabdosynochus pai n. sp. est caractérisé par un organe tétraloculé male de très grande taille (longueur interne 77 μm, longueur du c?ne 15, longueur du tube 47), le plus grand de toutes les espèces du genre, et un vagin sclérifié à structure très complexe, comprenant trois chambres secondaires, au lieu d’une comme c’est le cas chez la plupart des autres espèces. Pseudorhabdosynochus sp. est une espèce du ‘groupe cupatus’ qui n’est pas formellement décrite, mais des mesures sont indiquées. Un Ancyrocephalidae, Haliotrema sp., et un Capsalidae, Benedenia sp., étaient rares, et sont mentionnés mais non décrits. La faune des Diplectanidae de E. tauvina correspond au patron déjà trouvé dans un clade d’espèces de mérous, dont les membres hébergent souvent à la fois une espèce du ‘groupe cupatus’ et une autre espèce de Pseudorhabdosynochus Yamaguti, 1958.相似文献
18.
High incidence (up to 40%) of symptoms of yellowing and yellow mottling was observed in 5–8 years old orchards of kinnow mandarin
{Citrus reticulate Balanco (‘King’ × ‘Willow mandarin’)} in the Punjab state of India during a survey in January 2007. These symptoms are often
confused with nutrient deficiency and other stress related disorders. However, a greening bacterium has been attributed to
cause the disease. The disease was graft transmissible and sequencing of 16S rRNA, 16S/23S intergenic spacer region and 23S
rRNA of the greening bacterium associated with yellowing disease in kinnow mandarin confirmed it to be Candidatus Liberibacter asiaticus (‘Ca L. asiaticus’) showing maximum identity of 95.9% with ‘Ca L. asiaticus’ from USA and Brazil in 16S rRNA. The study indicates definite association of ‘Ca L. asiaticus’ with yellowing/chlorotic
mottling symptoms of greening disease of kinnow mandarin in Punjab state of India. 相似文献
19.
Carreras-Aubets M Repullés-Albelda A Kostadinova A Carrassón M 《Systematic parasitology》2011,79(2):145-159
The status of the trematode Aponurus laguncula Looss, 1907 in the western Mediterranean is re-assessed by means of a comparative morphological study and rDNA sequences
based on newly collected material. A. laguncula (sensu stricto) is redescribed from Trachinus draco L. and a new cryptic species of the ‘A. laguncula complex’, Aponurus mulli n. sp., is described on the basis of abundant material from Mullus barbatus L. (type-host) and M.
surmuletus L. off the Spanish Mediterranean coasts. The new species is differentiated from A. laguncula (sensu stricto) by its: significantly larger, elongate body, with maximum width at the level of the ventral sucker; shorter forebody; distinctly
larger sinus-sac, seminal receptacle and seminal vesicle, with the latter also being more elongate; vesicular pars prostatica;
more anteriorly located vitellarium, which consists of eight globular follicles; and distinctly smaller eggs, which are also
smaller in relation to body size and have both their opercular and anopercular poles rounded. The variability and the allometric
growth of the morphological characters in the new species were studied in detail, resulting in additional distinguishing features.
Sequences of the large subunit rRNA (28S) gene (domains D1–D3) and ITS2 rRNA gene region for the new species have been submitted
to GenBank in order to enhance future studies on species differentiation within the ‘A. laguncula complex’. 相似文献
20.
Sequencing of the internal transcribed spacer region ITS1 as a molecular tool detecting variation in the Stylosanthes guianensis species complex 总被引:1,自引:0,他引:1
J. Vander Stappen S. Van Campenhout S. Gama Lopez G. Volckaert 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(6-7):869-877
The internal transcribed spacer (ITS) regions 1 and 2 of the ribosomal DNA from Stylosanthes guianensis CIAT 1283 and cv ‘Schofield’ were amplified by polymerase chain reaction using conserved ITS primers from the 18S, 5.8S and
26S ribosomal genes flanking those regions. The entire region of 683 bp long was cloned, and seven clones were sequenced.
Comparison of the ITS spacer regions with published DNA sequences of other plant species revealed limited homology only; this
was in contrast to their comparison with the 5.8S rDNA sequences. The ITS1 region of 45 S. guianensis accessions was amplified by PCR and sequenced on both strands using the conserved primers ITS2-ITS5. These sequences, ranging
from 201 to 204 bp, were aligned to each other to assess intra-specific polymorphism. Within the S. guianensis (Aubl.) Sw. species complex, 11 DNA sequence types could be distinguished based on an insertion/deletion (indel) event and
15 single base-pair substitutions. In 1 of the S. guianensis types, two kinds of ITS1 sequence were observed in each individual, reminiscent of an incomplete homogenization of the repeat
structure in this type. Polymorphisms in the sequence of the ITS1 region were used to define molecular markers for S. guianensis on the basis of PCR-restriction fragment length polymorphism and selective PCR.
Received: 24 June 1997 / Accepted: 31 October 1997 相似文献