435 resultados para Tribe Hyoscyameae


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Floral organogenesis and development of Przeivalskia langutica Maxim, endemic to China and Hyoscyamus niger L. , which belong to the tribe Hyoscyameae (Solanaceae), were studied using scanning electron microscope. They have three common characters of floral organ initiation and development: 1) initia-tion of the floral organs in the two species follows Hofmeister's rule; 2) the mode of corolla tube development belongs to the "late sympetaly" type; 3) primordia of the floral appendages initiated in a pentameroua pattern and acropetal order. But initiation of the calyx-lobe primordia showed different modes in these two species. The calyx-lobe primordia of H, niger have simultaneously whorled initiation, while those of P, tangulica have helical initiation, but the five calyx-lobe primordia form a ring after all five calyx-lobe primordia occur. The systematic significance of the present results in the genera Hyoscyamus and Przeivalskia is discussed in this paper.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

本文研究了茄科天仙子族7属以及有亲缘关系的颠茄属、茄参属和枸杞属的形态学、解剖学、孢粉学、种子形态学、胚胎学、花器官发生、分子系统学和分支系统学;论述了它们的结构、分化和系统关系。主要内容包括: 1.解剖学 在光学显微镜和扫描电镜下,观察了茄科天仙子族(Hyoscyameae)7属21种及邻近4属4种共25种植物的叶表皮特征,结果表明:气孔器在各种植物的上、下的表皮均有分布,多为无规则型,也有不等细胞型;叶表皮细胞形状有不规则形、十字形、近长圆形和不规则多边形,垂周壁较平直或各种波状。叶表皮气孔器外拱盖内缘近平滑、浅波状或波状;角质膜多为具条纹,也有同时具条纹和颗粒或鳞片,偶尔仅具颗粒和鳞片或光滑。气孔器类型可以作为区分部分属的依据之一。颠茄叶表皮细胞形状和垂周壁式样在一些属和种中有一定的规律性,并与外部形态、孢粉学性状或地理分布相关;叶片表面角质膜的特征对属和种的划分也有一定意义。 2.种子形态学 在扫描电子显微镜下首次全面研究了天仙子族及颠茄属和茄参属等共10属25种植物的种子形态学特征,结果表明: 该族植物种子表面纹饰有脑纹状或近脑纹状和网状两大类,除了山莨菪属Anisodus和Hyoscyamus.pusillus 外,其余类群均为网状。外种皮细胞形状和周壁式样有两大类,一类为多边形至近圆形,等径,周壁近平直,另一类为形状不规则,常不等径,周壁为各式波状;外种皮细胞周壁内侧有皱波状、瘤状、小颗粒、片状或小刺等各式附属物。各属植物的种子大小、形状及种脐着生位置的系统学意义不大。但是,种脐突出与否、种子外种皮细胞形状和周壁式样,尤其是周壁内侧附属物等性状具有较大的分类学意义。 3.孢粉学 在扫描电镜下研究了该族7属及其它3属共10属23种植物的花粉形态学特征。结果表明:天仙子族的花粉粒形状为球形、近球形、扁球形和长球形;萌发孔类型有无萌发孔、不规则的拟孔、3沟、4 沟、3- 4沟、散沟和3孔沟;外壁纹饰为小刺状、瘤状、各式条纹状、条纹-穴状、条纹-网状、皱波状、细网状和网状。沟膜近光滑、具小颗粒、具小刺状突起或具瘤状突起。各属植物的花粉形态在萌发孔的有无、萌发孔的类型和外壁纹饰等方面有较大的差异,可以作为探讨属间分类和系统关系的重要依据。天仙子族植物花粉萌发孔的演化趋势为:无萌发孔→ 3、4沟→3孔沟。无萌发孔的山莨菪属是原始类群,三孔沟的马尿泡和天仙子等属是进化类群。 4.胚胎学 本论文首次研究了天仙子族山莨菪Anisodus tanguticus的胚胎学特征,结果表明:山莨菪的小孢子形成为同时型,腺质绒毡层;胚珠半倒生,单珠被,薄珠心;蓼型胚囊;其胚胎发生类型可能为茄型;胚乳形成为细胞型。山莨菪的胚胎学性状与马尿泡十分相似。胚胎学证据支持山莨菪属与马尿泡属关系密切的观点。 5.花器官发生 首次全面研究了天仙子族的山莨菪属(山莨菪)、马尿泡属(马尿泡)、天仙子属(天仙子)及其邻近2属共5种植物的花器官发生特征,结果表明:山莨菪和天仙子的5个花萼裂片原基突起最早发生,且几乎是近同时环状发生,其排列方式从花发育早期直至花成熟后始终为轮状排列。而马尿泡和颠茄首先是5个花萼裂片原基突起依次螺旋状发生,但在其5个花萼裂片原基都出现后,其排列方式仍为轮状排列。不同之处是:马尿泡的花萼裂片原基在其花冠裂片原基刚刚不明显地发生时,就已经在基部联合并形成了一个环,而颠茄的花萼裂片原基直到雄蕊原基突起开始发生并较明显时,花萼裂片原基仍然是分离的,当花顶的中央开始出现很不明显的雌蕊原基的凹陷时,花萼裂片原基才开始联合。青海茄参与其它4种植物的不同之处在于柱头2裂或3裂,而后4者的柱头均为2裂。花器官发生的特征表明马尿泡与天仙子和山莨菪的关系较近。 6.基于叶绿体DNA trnL-F序列和核糖体DNA ITS序列的初步分析 以宁夏枸杞作为外类群,对代表天仙子族及其邻近3属的10种植物的ITS区和trnL-F序列进行了测定,将这两个序列结合构建系统树。将gaps作为fifth base处理时,马尿泡属和茄参属构成最基部的一支,赛莨菪属和天仙子属构成一支然后与泡囊草属构成姐妹群,另外一支由天蓬子属、颠茄属和山莨菪属组成,其中天蓬子属与颠茄属构成一支后与山莨菪属构成姐妹群。分子证据只是一个尝试,还不足以说明天仙子族各属的系统关系。 7.分支分析 以枸杞属为外类群,基于形态学、叶表皮、种子形态学、孢粉学等特征对天仙子族7属及颠茄属和茄参属进行了分支分析。结果表明:目前公认的天仙子族7属构成一个单系类群,而颠茄属和茄参属并没有包括在内,它们两者构成一支,并与天仙子族形成姐妹群的关系。这与该族传统的分类结果相一致。 8.天仙子族的分化和系统关系 基于上述研究结果,结合天仙子族各属的现代地理分布,讨论了各属的分化和系统关系。认为根据传统分类包括有7个属的天仙子族是一个自然的单系类群,目前还没有足够的证据说明是否应该将颠茄属和茄参属放在天仙子族中。

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Floral organogenesis and development of two Solanaceae species, Anisodus tanguticus and Atropa belladonna, were studied by using scanning electron microscopy (SEM) as part of a project on systematics and evolution in the tribe Hyoscyameae. These two species share the following common characters of floral organ initiation and development: (1) initiation of the floral organs in the two species follows Hofmeister's rule; (2) the mode of corolla tube development belongs to the "late sympetaly" type, namely, petals are initiated separately and later become joined by fusion of their basal meristem, then rise together and form a corolla tube; (3) primordia of the floral appendages are initiated in a pentamerous pattern and acropetal order: sepals are initiated first, followed by the petals and stamens, and finally the carpels. The whorl of five stamen primordia forms almost simultaneously and originates opposite the sepal primordia, but initiation of the sepal primordia shows different modes in the two species. The sepal primordia of Anisodus tanguticus have simultaneously whorled initiation, while those of Atropa belladonna have helical initiation. The systematic significance of the present results in the genera Anisodus and Atropa is discussed in this paper.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Geelong, Victoria’s second city, has an AFL football club whose culture and identity is closely tied to the city itself. An analysis of its playing group for the colonial period demonstrates that this local tribalism began early. As football became professionalised towards the end of the nineteenth century, country Victoria lost power in relative terms to metropolitan Melbourne: for example, Ballarat’s three main clubs lost their senior status. But Geelong, with its one remaining senior club, prospered and was admitted to the VFL ranks in 1897. The Geelong players were the sons and nephews of the Western District squattocracy and so had access to networks of power and influence. Many attended the prestigious Geelong Grammar School and the worthy Geelong College (in surprisingly equal numbers). They pursued careers both on the land and in professional roles, and maintained the social connections they had built through the club and other local institutions. Despite their elite standing, however, they continued to be regarded by the supporter base as an embodiment of the city and a defence against the city’s Melbourne critics that Geelong was a mere ‘sleepy hollow’.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

With well over 700 species, the Tribe Dacini is one of the most species-rich clades within the dipteran family Tephritidae, the true fruit flies. Nearly all Dacini belong to one of two very large genera, Dacus Fabricius and Bactrocera Macquart. The distribution of the genera overlap in or around the Indian subcontinent, but the greatest diversity of Dacus is in Africa and the greatest diversity of Bactrocera is in south-east Asia and the Pacific. The monophyly of these two genera has not been rigorously established, with previous phylogenies only including a small number of species and always heavily biased to one genus over the other. Moreover, the subgeneric taxonomy within both genera is complex and the monophyly of many subgenera has not been explicitly tested. Previous hypotheses about the biogeography of the Dacini based on morphological reviews and current distributions of taxa have invoked an out-of-India hypothesis; however this has not been tested in a phylogenetic framework. We attempted to resolve these issues with a dated, molecular phylogeny of 125 Dacini species generated using 16S, COI, COII and white eye genes. The phylogeny shows that Bactrocera is not monophyletic, but rather consists of two major clades: Bactrocera s.s. and the ‘Zeugodacus group of subgenera’ (a recognised, but informal taxonomic grouping of 15 Bactrocera subgenera). This ‘Zeugodacus’ clade is the sister group to Dacus, not Bactrocera and, based on current distributions, split from Dacus before that genus moved into Africa. We recommend that taxonomic consideration be given to raising Zeugodacus to genus level. Supportive of predictions following from the out-of-India hypothesis, the first common ancestor of the Dacini arose in the mid-Cretaceous approximately 80 mya. Major divergence events occurred during the Indian rafting period and diversification of Bactrocera apparently did not begin until after India docked with Eurasia (50–35 mya). In contrast, diversification in Dacus, at approximately 65 mya, apparently began much earlier than predicted by the out-of-India hypothesis, suggesting that, if the Dacini arose on the Indian plate, then ancestral Dacus may have left the plate in the mid to late Cretaceous via the well documented India–Madagascar–Africa migration route. We conclude that the phylogeny does not disprove the predictions of an out-of-India hypothesis for the Dacini, although modification of the original hypothesis is required.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article analyses the occupational and class status of Geelong footballers in the nineteenth century via the methodology of prosopography. Prosopography is an empirical group biography approach to historical research. The article argues that during the period 1859-78 Geelong's playing group was largely derived from the squattocracy and urban middle class. In the later period 1878-96 the Geelong club recruited more widely from the working class, as in keeping with the increased participation of this class in football from the late 1870s. It can be argued that this more diverse group helped establish Geelong as a footballing power.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Phylogenetic relationships within the Tabanidae are largely unknown, despite their considerable medical and ecological importance. The first robust phylogenetic hypothesis for the horse fly tribe Scionini is provided, completing the systematic placement of all tribes in the subfamily Pangoniinae. The Scionini consists of seven mostly southern hemisphere genera distributed in Australia, New Guinea, New Zealand and South America. A 5757. bp alignment of 6 genes, including mitochondrial (COI and COII), ribosomal (28S) and nuclear (AATS and CAD regions 1, 3 and 4) genes, was analysed for 176 taxa using both Bayesian and maximum likelihood approaches. Results indicate the Scionini are strongly monophyletic, with the exclusion of the only northern hemisphere genus Goniops. The South American genera Fidena, Pityocera and Scione were strongly monophyletic, corresponding to current morphology-based classification schemes. The most widespread genus Scaptia was paraphyletic and formed nine strongly supported monophyletic clades, each corresponding to either the current subgenera or several previously synonymised genera that should be formally resurrected. Molecular results also reveal a newly recognised genus endemic to New Zealand, formerly placed within Scaptia. Divergence time estimation was employed to assess the global biogeographical patterns in the Pangoniinae. These analyses demonstrated that the Scionini are a typical Gondwanan group whose diversification was influenced by the fragmentation of that ancient land mass. Furthermore, results indicate that the Scionini most likely originated in Australia and subsequently radiated to New Zealand and South American by both long distance dispersal and vicariance. The phylogenetic framework of the Scionini provided herein will be valuable for taxonomic revisions of the Tabanidae.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new tribe, the Stereomerini, is established for four unusual genera: Stereomera Arrow, Termitaxis Krikken, Australoxenella n.gen., and Bruneixenus n.gen. The previously described genera are monotypic, as is Bruneixenus, the type species being B. squamosus n.sp. from Brunei. Australoxenella contains two new species, A. humptydooensis, type species, and A. bathurstensis, both from the Northern Territory, Australia. The relationships of the new tribe are analyzed and compared with the most closely related tribe, the Rhyparini, in the Aphodiinae. The tribe Rhyparini is redefined, and the genus Notocaulus Quedenfeldt is transferred to the Eupariini. A key to genera in both the Stereomerini and the Rhyparini is presented, important characters are illustrated, a cladogram is given, and convergence is discussed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The anuran tribe Paini, family Dicroglossidae, is known in this group only from Asia. The phylogenetic relationships and often the taxonomic recognition of species are controversial. In order to stabilize the classification, we used approximately 2100bp o

Relevância:

20.00% 20.00%

Publicador:

Resumo:

棘蛙族(Tribe Paini)隶两栖纲(Amphibia)、无尾目(Anura)、蛙科(Ranidae)、叉舌蛙亚科(Dicroglossinae),由棘蛙属(Paa)、倭蛙属(Nanorana) 和沙巴蛙属(Chaparana)构成(Dubois,1992)。由于特殊的形态特征和染色体核型,棘蛙族受到国内外学者的广泛重视和研究,但是到目前为止,棘蛙族的系统发育关系尚未明晰,族下属种的分类和归属问题还有待进一步研究和新的证据出现。本文通过光学显微镜、电子显微镜和石蜡切片对棘蛙族10 物种的精子和精巢进行研究,旨在了解棘蛙族精子的形态、量度、超微结构特征及不同季节精巢结构的变化规律,同时为棘蛙族的系统研究提供新的依据,也为棘蛙族濒危物种的保护和经济物种的繁殖提供基础资料。研究结果表明:棘蛙族各属物种精子的形态基本相似,精子整体呈线形,由头部、中片和尾部构成。精子头部呈长条状,顶体呈锥状,位于头部顶端并向前伸出,中片较长,尾部波动弯曲。棘蛙族各属物种精子量度差异较大,将各属物种精子头部、中片、尾部、头宽、尾宽的量度数据进行聚类分析,结果表明棘蛙族10 物种可分为三类:第一类包括棘侧蛙、合江棘蛙、小棘蛙、棘腹蛙和棘胸蛙,特点是精子较短,全长在72.6~103.35µm 之间;第二类包括倭蛙、高山倭蛙、腹斑倭蛙,特点是精子较长,全长在107.74~129.75µm 之间;第三类包括隆肛蛙和双团棘胸蛙,特点是精子最长,全长在145.89~165.84µm 之间。棘蛙族各属精子超微结构基本相似:精子头部由顶体、细胞核构成;中片由中心粒、线粒体构成;尾部由单根轴丝构成。精子顶体横切呈圆环状,细胞核电子密度高;线粒体为卵圆形,呈环状围绕轴丝排列,线粒体数目较多,约30层;尾部轴丝为典型的9+2结构,即由2根中央微管和9对外周微管组成。不同季节的倭蛙精巢结构变化表明倭蛙精巢每年只有一个生精周期,生精周期始于7 月,繁殖季节从5 月到6 月,生精高峰期为9 月;根据倭蛙不同季节精巢结构的变化,可将生精周期分为3 个阶段:第一阶段从7 月到9 月,为精子形成期;第二阶段从10 月到翌年4 月,为精子的贮存阶段,也即倭蛙的冬眠期;第三阶段从5 月到6 月,为精子的排放阶段,即倭蛙的繁殖期。不同季节的隆肛蛙精巢结构变化表明5 月为隆肛蛙的繁殖高峰期。根据棘蛙族各属精子的形态、量度和超微结构特征,结合已有的棘蛙族形态学、生态学、染色体核型及系统学研究成果,本文认为:1.基于精子数据对棘蛙族的划分和基于形态学及分子系统学数据对棘蛙族的划分均有相同之处,精子形态结构可为棘蛙族的系统研究提供新的证据。2. 棘蛙族各属精子的形态、量度及超微结构不仅与蛙科其他属种有明显差异,而且在无尾类中也较为特殊,精子学研究结果支持将棘蛙族从蛙科中分离出来,归隶于叉舌蛙科的叉舌蛙亚科的系统学修正。3. 精子的顶体、细胞核、中片的形态结构及量度可作为蛙科的分类指标。On the base of unique morphological and kyrotype characters, Dubois(1992)recognized three genera Paa, Narnorana, Chaparana as tribe Paini, which is amember of Dicroglossinae, Ranidae. In present study, the sperm shape, size andultrastructure of 10 paini species were investigated through the light and electronmicroscope, and testis structure of N. pleskei and F. quadrana was also studied. Wesuppose this study could offer some spermatological evidence to phylogeny andreproduction study of tribe Paini. The results were as follows:The sperm shape of tribe paini is homologically similar, the spermatozoa arefiliform, composed of elongate head, long mid-piece and waved tail. The acrosome isapically associated with the nucleus and extend anteriorly.The sperm length of tribe paini differ remarkably among genera. Cluster for thelength of sperm head, mid-piece, tail, total length, head-width, tail-width of ten painifrogs indicated the 10 species could be separated into three groups: GroupⅠcontainsP. shini, P. robertingeri, P. spinosa, P. exilispinosa, P. boulengeri, the spermatozoa ischaracterized with short in total length, ranging from 72.6µm to 103.35µm; GroupⅡcontains N. pleskei, N. parkeri, N. ventripunctata, the spermatozoa ischaracterized with relatively long in total length, ranging from 107.74µm to129.75µm; Group Ⅲ contains F. quadrana and P. yunnanensis, the spermatozoa is characterized with longest in total length, ranging from 145.89µm to 165.84µm. thethree groups based on spermatological data is partially match the classification basedon morphological and molecular data.The ultrastructure of spermatozoa in tribe paini is also basic similar, includingacrosome vescile, nuleus of the head proper, centriole, mitochondriol of themid-pieces, axoneme of the tail. The acrosome vescle is circle in TEM transversesection, the density of nucleus is high; The mitochondrions is oval, surrounding theaxial filament with about 30 layers of mitochondria; The axoneme has the typical 9+2pattern of microtubules.The seasonal changes in testis of N. pleskei indicates it has only onespermatogenesis circle, which begin in July, the reproduction season is from May toJune, the spermatogenesis is active in September. On the base of seasonal changes intestis, the spermatogenesis circle can be separated into three stages: In stageⅠfromJuly to September, spermatids are formed; In stage Ⅱ from October to April next year,the spermatozoa are stored in testis,which is the hibernated period; In stage Ⅲ fromMay to June, mature spermatozoa were released from the testis, which is thereproduction season of N. pleskei. As to F. quadrana, reproduction is active in May.With the previous study of morphology, ecology, karyotypes and phylogenyresearch of tribe Paini, the spermatological data in present study suggests:1. The spermatological classification of tribe paini is partially consistant with themorphological and molecular classification respectively.2.The sperm morphology and ultrustructure of tribe paini is unique not only inthe family Ranida but also in Anura, which suggest the tribe paini is monophyletic andmight be transfered from the family Ranida to the family Dicroglossidae based onmolecular evidence.3. The acrosome, nuleus, shape, length and ultrastructure of mid-piece can beused as an alternative taxonomic character in Anura.