共查询到19条相似文献,搜索用时 62 毫秒
1.
广义竹叶青蛇属Trimeresurus (sensu lato)的分类和系统学研究进展 总被引:1,自引:1,他引:1
广义的竹叶青蛇属于Trimeresurus(sensu lato)包含有40多个物种,广泛分布在南亚和东南亚国家和地区。目前,该类群已经相继被划分为6个属:Trimeresurus(sensu stricto)、Tropidolaemus、Ovophis Protobothrops,Triceratolepidophis,Zhaoermia本文从形态、细胞以及分了系统学等方面对Trimeresurus(sensu lato)的分类和系统学研究进行综述。 相似文献
2.
满江红属系统学研究的新进展 总被引:2,自引:0,他引:2
本文从植物系统学角度对满江红属的研究进展作了全面综述,近年来从细胞水平提出了将满江红属重新划分为Azolla和Tetrasporocarpia2个亚属,经典的三膘(Azolla)和九膘(Rhizosperma)亚属作为新的Shbgen,Azolla中的2个组(Section),而原有九膘亚属中的A.nilotica则为Subgen,Tetrasporocarpia的一个种,遗传育种和同工酶的研究证据对A.mexicana,A.microphylla和A.caroliniana能否在Sect.A-zolla中占据3个种的分类地位提出疑问,但要完全解决满江红属的系统学问题,分子生物学技术是重要手段,由于满江红为蕨-藻共生体,其样本的异质性影响了现有分子标记研究结果的可靠性。 相似文献
3.
本文从植物系统学角度对满江红属的研究进展作了全面综述。近年来从细胞研究水平提出了将满江红属重新划分为〖WTBX〗Azolla和Tetrasporocarpia 2个亚属,经典的三膘(Azolla)和九膘(Rhizosperma)〖WTBZ〗亚属作为新的Subgen Azolla中的2个组(Section),而原有九膘亚属中的A.nilotica则成为Subgen.Tetrasporocarpia〖WTBZ〗的一个种。遗传育种和同工酶的研究证据对A.mexicana,A.microphylla和A.caroliniana能否在Sect. Azolla中占据3个种的分类地位提出疑问。但要完全解决满江红属的系统学问题,分子生物学技术将是重要手段。由于满江红为蕨 藻共生体,其样本的异质性影响了现有分子标记研究结果的可靠性。 相似文献
4.
采用比较形态学方法,本文详细地描述了赤属植物根、根状茎、茎、卷须、花序、花萼、花冠、雄蕊群、雌蕊群、果实、种子以及毛被的形态特征,并讨论了某些形态学性状的系统学意义。本文首次描述和记录了该属植物的传粉生物学特征以及传粉媒介,并讨论了造成该属某些种结实率低的原因。本文还根据现存赤属及其近缘属植物的分布式样以及它们的属下分类群的系统演化式样,确定了中国的横断山系和大巴山系地区是该属植物的现代分布中心和分化中心,而中国云南南部和中南半岛北部地区的季节性山地雨林是该属植物的起源中心。在综合大量资料的基础上,本文对赤属作了分类学修订。确认该属有22种,2变种,归并了2种和10变种。 相似文献
5.
6.
采用比较形态学方法,本文详细地描述了赤包属植物根、根状茎、茎、卷须、花序、花枣、花冠、雄蕊群、雌蕊群、果实、种子以及毛被的形态特征,并讨论了某些形态学性状的系统学意义。本文首次描述和记录了该属植物的传粉生物学特征以及传粉媒介,并讨论了造成该属某些种结实率低的原因。本文还根据现存赤包属及其近缘属植物的分布式样以及它们的属下分类群的系统演化式样,确定了中国的横断山系和大巴山系地区是该属植物的现代分布中心和分化中心,而中国云南南部和中南半岛北部地区的季节性山地雨林是该属植物的起源中心。在综合大量资料的基础上,本文对赤包属作了分类学修订。确认该属有22种,2变种,归并了2种和10变种。 相似文献
7.
8.
黄耆属簇毛黄耆亚属系统学研究 总被引:1,自引:0,他引:1
簇毛黄耆亚属以其柱头上具簇毛等形态特征与黄耆属其它类群相区别,约含49种(变种)。主要分布在青藏高原及其邻近地区,绝大多数种类分布于横断山区。本文基于形态特征和分支系统学方法分析亚属内种系发生关系。结果表明,49种(变种)可分为9组。其中双小苞组Sect.Bibracteolati含种类最多,是一个并系类群。借助于分支图,分析了6个较重要的鉴定特征的演化,习性,茎的着生方式,小苞片,果实形态,柱头具簇毛,果实膨胀状况等。最后作出了这个亚属的一个分类纲要。 相似文献
9.
利用基于ITS序列的分子系统学对国产堇菜属(Viola L.)进行了系统发育重建,选择Hybanthus concolor和鳞隔堇(Scyphellandra pierrei)作为外类群,对国产堇菜属植物54种1亚种共66个序列进行分析。分子系统树中获得强烈支持的中国堇菜属属下组级分类群有Sect.Viola、Sect.Diffusae、Sect.Bilobatae、Sect.Vaginatae。Subgen.Melanium与Sect.Viola和Sect.Trigonocarpae聚在一起,说明它们的亲缘关系较近,但Sect.Trigonocarpae支获得的支持率较低。分子系统树证实了Subgen.Dischidium与Subgen.Chamaemelanium的近缘关系,但不支持根据距的长短将Subgen.Dischidium划分为Sect.Longicalcaratae和Sect.Brevicalcaratae的处理。而Pinnatae类群应该作为Sect.Adnatae下的一个亚组处理。根据分子系统发育和形态学特征对V.lucens、V.magnifica、V.dissecta、V.yunnanensis等的分类地位进行了重新评价。 相似文献
10.
11.
Although Bacillus cereus sensu lato are important both from an ecological and an economical point of view, little is known about their population structure, ecology, and relationships with other organisms. In the present work, the genotypic similarity of arthropod-borne B. cereus s.l. isolates, and their symbiotic relationship with the host are assessed. Bacilli of this group were recovered from the digestive tracts of sow bugs (Porcellio scaber) collected in three closely located sites. Their genotypic diversity was investigated using pulse-field gel electrophoresis (PFGE) following the whole-genome DNA digestions with NotI and AscI, and PCR amplification of virulence genes. The majority of the sow-bug Bacillus cereus sensu stricto isolates originating from the same but also from different sites displayed identical PFGE patterns, virulence gene content and enterotoxicity, indicating strong genetic and genomic relationships. The sow-bug Bacillus mycoides/Bacillus pseudomycoides strains displayed a higher diversity. The isopod-B. cereus s.l. relationship was also evaluated using antibiotic-resistant derivatives of B. cereus s.s., B. mycoides/B. pseudomycoides and Bacillus thuringiensis reintroduced into sow bugs. Both spores and vegetative cells of B. cereus s.l. were recovered from sow bugs over a 30-day period, strongly suggesting that these bacteria are natural residents of terrestrial isopods. 相似文献
12.
Craig R Williams 《Australian Journal of Entomology》2005,44(2):110-112
Abstract The timing of host-seeking behaviour was studied in two mosquito species, Anopheles annulipes sensu lato and Coquillettidia linealis at Mundic Creek, near the Upper River Murray in South Australia. Hourly sampling using carbon dioxide-baited traps revealed consistent patterns in the timing of host-seeking. Coquillettidia linealis displayed a very large peak in host-seeking activity at sunset, followed by a much reduced level throughout the night and a smaller peak at sunrise. Anopheles annulipes s.l. differed by displaying a significantly smaller peak at sunset, followed by higher amount of activity throughout the night compared with Cq. linealis . The two taxa, while both crepuscular and nocturnal, spread their host-seeking effort out differently throughout the night, indicating that they have different resource requirements. 相似文献
13.
Cassia L. sensu lato, a large heterogeneous genus of flowering plants, occurs naturally in the tropics around the world. Recent works based on floral morphology have supported a division of this genus into three genera, namely Cassia L. s. str., Chamaecrista Moench and Senna Mill. In order to investigate this new classification, 508 specimens of 18 taxa of the genus Cassia s.l. grown in Thailand were analyzed using cluster analysis and canonical discriminant analysis. The total 32 vegetative and reproductive morphological characters were employed in these analyses. In cluster analysis, Cassia s.l. can be separated into four groups, respectively viz. Chamaecrista, Senna alata, Senna and Cassia s /str. The four-cluster grouping is discussed. From a canonical discriminant analysis using the four-cluster grouping as a priori groups, it can be concluded that Cassia s. str., Senna, and Chamaecrista are indeed distinct taxa. The three most important characters that separate the three genera are filament length, fruit length, and ovary stalk length. These quantitative characters, together with some qualitative characters, were useful in constructing an identification key to these genera. Among the three genera, it was also found that Senna is rather a heterogeneous taxon. The difference between the studied species was discussed. 相似文献
14.
In the present study we analyzed stability of plasmid content in 34 Borrelia strains of three different species (13 Borrelia afzelii, 10 Borrelia garinii and 11 Borrelia burgodorferi sensu stricto) using pulse field gel electrophoresis (PFGE). During long-term in vitro cultivation consisting of 50 passages, plasmid loss was established in 46% of B. afzelii, 40% of B. garinii and 36% of B. burgdorferi sensu stricto strains. Loss of plasmids occurred as early as between the 5th and 10th passage, affected only plasmids in the range 9-41 kb but not plasmids in the range 50-68 kb and manifested with the loss of one to up to three plasmids. 相似文献
15.
Xiaomin Hu Izabela Swiecicka Sophie Timmery & Jacques Mahillon 《FEMS microbiology ecology》2009,70(3):12-23
Eighty soil-borne Bacillus cereus group isolates were collected from two neighbouring geographical sites in Belgium. Their genetic relationships and population structure were assessed using Multilocus sequence typing analysis of five chromosomal genes, while the contribution of extrachromosomal elements to the population dynamics was gauged by the presence, diversity and transfer capacity of pXO1- and pXO2-like plasmids. Globally, the bacterial population displayed a broad diversity, including an important subpopulation of psychrotolerant isolates related to Bacillus weihenstephanensis . pXO1- and pXO2-like replicons were present in 12% and 21% of the isolates, but no Bacillus anthracis -related toxin genes were found. Furthermore, only one of the isolates containing a pXO2-related plasmid was shown to be able to mobilize small non-self-conjugative plasmids. Interestingly, several B. cereus sensu lato isolates displaying the same sequence type were observed to have different plasmid contents, suggesting the occurrence of horizontal gene exchange. Similarly, a number of pXO2-like replicons with identical sequences were found in distinct bacterial isolates, therefore strongly arguing for lateral transfers among sympatric bacteria. 相似文献
16.
Raja Chaabane-Banaoues Myriam Oudni-M’rad Selim M’rad Habib Mezhoud Hamouda Babba 《The Korean journal of parasitology》2016,54(1):113-118
Hydatidosis has become a real concern for health care institutions and animal rearers in Tunisia. The Tunisian endemicity is aggravated by the growing number of dogs and the difficulty of getting rid of contaminated viscera because of the lack of equipment in most slaughterhouses. Therefore, microscopic and molecular tools were applied to evaluate the role of slaughterhouses in canine infection and Echinococcus granulosus sensu lato (s. l.) egg dissemination. Exposure risk to E. granulosus s. l. eggs in urban and rural areas was explored in order to implant preventive and adapted control strategies. Microscopic examinations detected taeniid eggs in 152 amongst 553 fecal samples. The copro-PCR demonstrated that 138 of 152 taeniid samples analyzed were positive for E. granulosus s. l. DNA. PCR-RFLP demonstrated that all isolated samples belonged to E. granulosus sensu stricto (s. s.). An important environmental contamination index (25.0%) by E. granulosus s. l. eggs was demonstrated. The average contamination index from the regions around slaughterhouses (23.3%; 95% CI: 17.7-28.9%) was in the same range as detected in areas located far from slaughterhouses (26.0%, 95% CI: 21.3-30.8%). Echinococcosis endemic areas were extended in both rural (29.9%, 95% CI: 24.8-34.9%) and urban locations (18.1%, 95% CI: 13.0-22.9%). The pathogen dissemination is related neither to the presence/absence of slaughterhouses nor to the location in urban or rural areas, but is probably influenced by human activities (home slaughtering) and behavior towards the infected viscera. 相似文献
17.
Beklemishev AB Dobrotvorsky AK Piterina AV Ivanov ID Nomokonova NY Livanova NN 《FEMS microbiology letters》2003,227(2):157-161
The prevalence of Borrelia burgdorferi sensu lato (s.l.) genospecies in West Siberia as well as in many other regions of Russia remains insufficiently investigated. In the present study a total of 151 adult female ticks Ixodes persulcatus Schulze, collected at three localities in eastern regions of West Siberia, where Lyme disease is endemic, were examined for the presence of the spirochete B. burgdorferi s.l. by polymerase chain reaction targeting the 23S-5S rRNA intergenic spacer regions. Spirochetal DNA was detected in on average 15.2+/-3.0% of the ticks examined. The infection rate of adult ticks with B. burgdorferi s.l. at various localities ranged from 8.6+/-3.4% to 29.0+/-7.6%, being greatest in the northernmost site studied and decreasing southwards. The restriction patterns obtained after MseI digestion of the 23S-5S rRNA intergenic spacer amplicons assigned 23 DNA samples to the following genomic groups: 19 to B. garinii (12 to group NT29 and seven to group 20047(T)), three to B. afzelii, and one to mixed B. afzelii and B. garinii NT29. We have not detected other genospecies, which were found in ticks in Europe, the Russian Far East and Japan. Thus, the ticks examined were associated only with two genospecies of Borrelia burgdorferi s.l. pathogenic to humans (B. garinii and B. afzelii), and B. garinii was the major genospecies infecting adult I. persulcatus in eastern regions of West Siberia. 相似文献
18.
Koci J Movila A Taragel'ová V Toderas I Uspenskaia I Derdáková M Labuda M 《Experimental & applied acarology》2007,41(1-2):147-152
We examined 198 questing Ixodes ricinus ticks collected in Chisinau City, Republic of Moldova by PCR assays for Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato and co-infection of both pathogens, which were detected in 9%, 25.2% and 2.5% of tested ticks, respectively. B. burgdorferi s.l. genotyping revealed the presence of five genospecies with dominance of B. garinii. Our preliminary study provides evidence about occurrence of both pathogens in this populated area, which represent a potential health risk for inhabitants. 相似文献
19.
B.L. Parker M. Skinner S.Y. Gouli V.V. Gouli D. Tobi 《Biocontrol Science and Technology》2015,25(7):768-788
Persistence of granular formulations of Beauveria bassiana sensu lato, strains GHA726 and ERL1170, and Metarhizium anisopliae sensu lato, strains ERL824 and ERL701, applied to forest soil was documented. One formulation was prepared by producing fungi on millet and at application adding cooked, dried millet to provide additional nutrients for fungal growth. The other was made by producing fungi on corn starch ‘packing peanuts’, a biodegradable packaging material, adding additional packing peanuts as a nutrient base. The trial was conducted in three sites in a forest predominating in sugar maple (Acer saccharum) in Underhill, VT, USA. In each site, 33 dominant sugar maples were randomly selected. A 1-m2 plot located 1 m from the bole of the tree was established. Soil samples were collected before application, and 1 h, 2, 4, 8, 12 and 16 wk post-application. Fungal levels were estimated based on number of colony-forming units (CFUs). A significant increase in CFUs was observed 2 wk post-application in plots treated with isolates GHA726, ERL1170 and ERL824 as a result of fungal reproduction on nutrients in the formulations. Evidence of greater persistence for the B. bassiana than the M. anisopliae isolates was observed, based on CFU levels over time. Isolates formulated with millet proliferated more than those on packing peanuts. Use of entomopathogenic fungi in forest soil has potential for managing soil-dwelling insect pests such as pear thrips, Taeniothrips inconsequens, and the black vine weevil, Otiorhynchus sulcatus, though the type of formulation and the specific isolate used must be selected carefully. 相似文献