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1.
A new species of the genus Boletus is reported from Fujian Province: Boletus minimus Zang et N.L.Huang. It is a rather interesting taxon and characterized by its most small size of basidiocarps, pileus 1-4 mm diam., stipes 3-6 mm long only., it can be placed in the genus Boletus section Luridi Fr.  相似文献   

2.
Reserve Lipids in Stem Root Primordia of Poplar   总被引:1,自引:0,他引:1  
Lipids are reserve substances in stem root primordia of poplarand occur as droplets approximately uniformly in all cells ofroot primordia. In ultrathin sections they appear as sphericalelectron-dense particles (0.5–1.4 µm diameter),filling up virtually all the available space in the cytoplasm.The presence of lipids in stem root primordia was demonstratedin several species of the genus Populus from the section Aigeirosand Tacamahaca, as well as in another representative of thefamily Salicaceae, viz. in the genus Salix.  相似文献   

3.
The genus Notopterygium is endemic to China. The plants of this genus are important traditional Chinese medicine. When established by H. de Boissieu in 1903, Notopterygium included only two species, i.e.N. franchetii and N. forbesii. Within nearly a century, five more specific names had been added to this genus, i.e.N. forrestii H. Wolff, N. oviforme Shan, N. incisum Ting ex H. T. Chang, N. pinnatiinvolucellatum Pu et Y. P. Wang, N. tenuifolium Sheh et Pu. Based on field ervation and examination of herbarium specimens, all the taxa in this genus were taxonomically reviewed and their nomenclature was carefully checked. N. oviforme was treated as a subspecies under N. forbesii. We agree with Chang He-Tseng in reducing N. franchetii to N.forbesii as a synonym. As a result, five species, one of which contains a subspecies, are recognized. Based on the morphology of involucel bractlets as well as their relevant characters, Notopterygium is divided into two sections.Sect. 1. Notopterygium Basal and proximal cauline leaves 2-ternate to 2 ~3-ternate-pinnate, ultimate divisions broadovate or ovate-lanceolate; involucel bractlets linear, entire, vascular bundles of petiole approximately equal in size. This section contains two species and one subspecies.Sect. 2. Tenuifolium Pu, sect. nov.Basal and proximal cauline leaves 2 ~3-ternate-pinnate, ultimate divisions ranceolate,ovate-lanceolate or linear; involucel bractlets linear, entire or oblanceolate, 2 ∽ 3-fid or pinnate at the apex; vascular bundles of petiole unequal in size. This section centains three species.  相似文献   

4.
我国牛肝菌属一新种,微眇牛肝菌   总被引:3,自引:1,他引:3  
在福建省新发现一担子果极小的微眇牛肝菌,其盖径仅1-4mm,柄高3-6mm,极罕见,暂归于牛肝菌属黄肉牛肝菌组。  相似文献   

5.
Discussed in the present paper are evolutionary trends of important morphological characters of Deutzia, systematic position of several closely related genera, geographical distribution and characteristics of floristic elements. Finally the classificatory revison of the genus is made and a key to species is given. As a result, evolutionary trends of the important morphological characters in Deutzia are suggested; petals from imbricate to valvate, stamens from indefinite to definite, filaments from edentate to dentate, ovary from half-inferior to inferior. Therefore, the section Neodeutzia with valvate corolla and infinite stamens with edentate filaments should be included in this genus. The sections Neodeutzia and Mesodeutizia seem to be better considered as primitive taxa, while the section Deutzia advanced one. There are 52 species of Deutzia in China , which are grouped into two sections ( Sect. Mesodeutzia, Sect. Deutzia), four subsections (Subsect. Deutzia, Subsect. Grandiflorae, Subsect. Stenosepalae, Subsect. Cymosae)and 17 series. Sixty- five species are so far recognised in the genus Deutzia. They are mainly distributed in E. Asia and disjunctively in N. America. China is therefore an area the richest in species of Deutzia in the world, making up 80% of the total species of this genus. The greatest concentration area is in Sichuan (23 species), Yunnan (21 species), Hubei (12 species) and Shanxi (10 species), this is boundary area between Sino-Himalayan subregion and Sino-Japanese subregion, where occur abundant species (including 39 endemic species) and diverse taxa (2 section and 4 subsection). Based on these facts it is proposed that the present center of distribution and differentiation of Deutzia be in the southern part of the Hengduan Mountains, the Qingling Range and C. China.  相似文献   

6.
论世界芨芨草属(禾本科)的地理分布   总被引:12,自引:0,他引:12  
本文详细讨论了世界芨芨草属的地理分布等问题。1.全世界芨芨草属共有23种1变种,分为5个组。本文对它们进行了系统介绍。2.属的地理分布,最北为北纬62°(羽茅、毛颖芨芨草),最南为北纬26°(林阴芨芨草)。就海拔而论,分布最低的海拔记录为120m(雀麦芨芨草),分布最高的海拔记录为4600m(干生芨芨草和藏芨芨草)。3.本文讨论了芨芨草属5个组(芨芨草组,钝基草组,直芒草组,新芨芨草组,拟芨芨草组)的系统位置,和每个组包括的种类及5个组的分布格局。4.根据塔赫他间世界植物区系区划,统计了每个区的种数,明显看出伊朗—土兰区种类(18/24)是第一位,东亚区(14/24)居第二位。中国有17种,横断山脉地区、华北地区和唐古特地区种数最丰富(10种和9种)。5.研究结果表明:(A)从种的分布格局分析可见,横断山脉地区北部、唐古特地区东部和华北地区西部的交汇地是芨芨草属分布中心。(B)根据芨芨草属形态特征演化趋势分析和地史学资料推测横断山脉地区北部是芨芨草属的起源地。(C)有三条路线向外散布:a)从横断山脉地区向西沿喜马拉雅山脉,经克什米尔地区抵达地中海和中欧;b)从横断山脉向西北经祁连山、天山、塔里木盆地西侧山地,抵吉尔吉斯斯坦伊塞克湖; c)由横断山脉向东北经甘肃、宁夏、陕西、山西、河北和东北,抵达西伯利亚,东达堪察加半岛,西至鄂毕河上游,并经白令海峡陆桥分布到美国内华达山脉和落基山山脉。(D)该属植物集中分布于北半球半湿润、半干旱和干旱地区,以及极端干旱的荒漠区山地。植物的形成、发展和生态适应与气候相联系,并经过长期的适应和进化,塑造了一系列中生、旱中生的形态-生态特征和生活型。  相似文献   

7.
Niehuis O  Judson AK  Gadau J 《Genetics》2008,178(1):413-426
The haplodiploid wasp genus Nasonia is a promising model for studying the evolution of genic incompatibilities due to the existence of interfertile species and haploid males. The latter allows for significantly reducing the sample size required to detect and map recessive dysfunctional genic interactions. We exploited these features to study the genetics of intrinsic hybrid inviability in male F2 hybrids of Nasonia giraulti and N. vitripennis. Analyzing marker segregation in 225 hybrid embryos, we inferred a linkage map with 38 framework markers. The markers were tested for marker transmission ratio distortion (MTRD) and interchromosomal linkage disequilibrium in populations of embryonic and adult hybrids. We found evidence for four transmission ratio distorting loci (TRDL). Three TRDL showed a deficit of the N. giraulti allele in hybrids with N. vitripennis cytoplasm. A separate TRDL exhibited a deficiency of the N. vitripennis allele in hybrids with N. giraulti cytoplasm. We ascribe the observed MTRD in adult hybrids to cytonuclear genic incompatibilities causing differential mortality during development since hybrid embryos did not show MTRD. The identified cytonuclear genic incompatibilities in F2 hybrids with N. vitripennis cytoplasm account for most of the intrinsic hybrid inviability in this cross. The high mortality rate in F2 hybrids with N. giraulti cytoplasm cannot be explained by the single identified TRDL alone, however.  相似文献   

8.
9.
The halophytic genus Suaeda (Chenopodiaceae) includes species with the C3 and C4 photosynthetic pathways. North American species of this genus were investigated to determine whether C3 and C4 leaf anatomy are consistent within the two sections of Suaeda, Chenopodina and Limbogermen, present on this continent. All species from section Chenopodina were found to possess C3 anatomy, whereas all species from section Limbogermen were found to be C4 species. Characteristics of leaf anatomy and chloroplast ultrastructure are similar to those reported from C3 and C4 species, respectively, from the Eastern Hemisphere. All species from section Limbogermen have the suaedoid type of leaf anatomy, characterized by differentiation of the mesophyll into palisade parenchyma and a chlorenchymatous sheath surrounding central water-storage tissue, as well as leaf carbon isotope ratios (_13C) of above -20. All species from section Chenopodina have austrobassioid leaf anatomy without a chlorenchymatous sheath and _13C values of below -20. According to our literature review, the photosynthetic pathway has now been reported for about half (44) of the Suaeda species worldwide. The C3 and C4 photosynthetic syndromes are with few exceptions distributed along sectional or subsectional lines. These findings throw new light on the infrageneric taxonomy of this genus.  相似文献   

10.
嵩草属植物硅酸体系统的研究   总被引:1,自引:0,他引:1  
邓德山 《广西植物》2002,22(5):394-T003
对国产狭义嵩草属 (K obresia,Cyperaceae) 3个组 2 7种植物进行了硅酸体系统分析研究 ,同时结合近缘的苔草属 (Carex) 2个组的植物硅酸体特征 ,深入探讨了植物硅酸体系统分析研究在莎草科苔草族 (Cariceae)中的系统分类学意义。认为 :(1 )嵩草属及其临近类群在属间、种间及种下水平的系统分类学比较研究都可以借助植物硅酸体系统研究的证据。 (2 )穗状嵩草组 (sect. Elyna)的硅酸体系统特征具有较高的一致性 ,除矮嵩草 (K.humilis)及其近缘种同其他穗状嵩草组的种类有所不同 ,它很可能有一个不同于穗状嵩草组其他类群的嵩草组(sect. K obresia)的亲缘。 (3 )从植物硅酸体系统特征的研究来看 ,拟苔草组 (sect. H emicarex)的一些种接近于穗状嵩草组 ,如高山嵩草 (K . pygmeae) ;而另一些种接近于嵩草组 ,如禾叶嵩草 (K . graminifolia) ;也有一些种类的硅酸体系统特征更接近苔草属 ,说明这个组很可能是多源的 ,即本组的单一花穗和果囊形态特征由不同类群的复合花序种类趋同演化而出。(4 )嵩草组的硅酸体系统特征具有较高的一致性 ,说明嵩草属原始类群在硅酸体系统特征方面与外部形态特征演化的某些相关性。  相似文献   

11.
Nicotiana tabacum (tobacco, Solanaceae) has two 5S ribosomal DNA (rDNA) families, one of unit length approximately 646 bp and the other -430 bp, that differ in the length of the 5S rDNA non-transcribed spacer (NTS). The long 5S rDNA family, found on the T genome of tobacco and in Nicotiana tomentosiformis, contains a GC-rich subregion that is absent in the short family. We designed primers for this subregion and generated a probe that we used against a range of Nicotiana and related Solanaceous species. We demonstrated the presence of the GC-rich subregion in a range of Nicotiana species, but it was absent in Nicotiana sylvestris, Nicotiana longiflora, and two closely related genera, Petunia and Solanum. These data suggest that this subregion of the NTS is likely to have evolved with the genus Nicotiana. The absence of the subregion in N. sylvestris and N. longiflora is likely to have arisen by a deletion event in the evolution of section alatae. We demonstrate patterns of evolution in the 5S rDNA unit cluster in relation to a phylogenetic reconstruction of species relationships in section tomentosae. Nicotiana glutinosa diverged early from the section and contains a 5S rDNA family based on a 550-bp unit. After this divergence, 430- and 650-bp rDNA unit families evolved. The 650-bp family is found in all species of tomentosae (except N. glutinosa) and in tobacco. The 430-bp family within tomentosae includes the GC-rich subregion and is thus unrelated to the 430-bp family in N. sylvestris. Nicotiana setchellii is unusual in that it has three 5S rDNA loci, including one locus that is exceptionally large. This species, unique to tomentosae, has a very abundant 900-bp unit family. It is possible that this 900-bp family occurs on this one large locus. In N. tomentosa and N. kawakamii, the 650-bp family is predominant, whereas N. tomentosiformis and N. otophora have only the 650-bp family. There is no clear relationship between the number of 5S families and the number of 5S rDNA loci. Certainly the replacement of 5S rDNA units, perhaps by gene conversion, has occurred repeatedly in the evolution of genus Nicotiana.  相似文献   

12.
中国杭子梢属植物的研究   总被引:2,自引:0,他引:2  
傅沛云 《植物研究》1987,7(4):11-55
本文叙述了杭子梢属(gen.Campylotropis)植物的研究历史,说明在中国一共记录过59种杭子梢属植物,经过著者的研究整理,确定并提出了14种新的异名名称,经过详细考订,本属植物在中国已确知为29种、6变种、6变型。其中包括经发现和研究整理的新种4、新变种3、新变型3、新组合变种2、新组合变型3。此外尚有2个存疑种有待今后采集调查解决。本文历述了关于本属是否应该并入胡枝子属(gen.Lespedeza)这一问题所存在的长期争议之后,详细论述了本属与胡枝子属在特征上的异同诸点、进行了比较和分析,据此,明确地肯定本属与胡枝子属亲缘关系极为相近,但特征的分化已经必须确认本属应是与胡枝子属有明确区别的独立的属。此外,从特征分析中也可得出本属应是由胡枝子属大胡枝子组(sect.Macrolespedeza)演化发展而来的。本文在讨论了属内主要特征的演化趋势与种群关系之后,论述了本属在世界主要分布地区的种数和分布概况,同时将此与胡枝子属大胡枝子组的分布概况作了比较和分析,明确地认定我国机子梢属植物的大部分种类是本国西南地区发生的(中国有20个特有种),我国的西南地区是本属植物的分布中心,也是本属植物从较原始特征开始分化的一个特征分化多样化中心,并且此地区正是胡枝子属大胡枝子组与本属多数种类包括较原始种类分布相交叉的地区,因而我国的西南地区有可能即是本属植物的起源中心,并且这一起源应是与胡枝子属大胡枝子组植物分布到中国西南地区以后的分化发展想联系的。  相似文献   

13.
In this paper, we analyzed the phylogeny of the section Bulbocodii (genus Narcissus; Amarillydaceae) using the matK and trnL-F fragments of cpDNA in order to review the validity of the recognized taxa. Our results indicate that Narcissus obesus should be considered a valid species, and that N. blancoi is a distinct taxon. In addition, seven previously recognized species, N. juressianus, N. subnivalis, N. graellsii, N. conspicuus, N. citrinus, N. nivalis, and N. quintanilhae, should be assigned to an infraspecific rank under N. bulbocodium, as they are not valid species. In addition, we analyzed the distribution of the three morphological characters widely used in the systematics of this section and found that their variation does not agree with the phylogenetic results, rendering these characters limited taxonomical utility. This result suggests that the section Bulbocodii shows high morphological lability, which can explain the proliferation of nominal species.  相似文献   

14.
论世界蒿属植物区系   总被引:15,自引:2,他引:13  
林有润 《植物研究》1995,15(1):1-37
本文从多学科, 包括形态、地理分布、孢粉、古植物、谱系分支分析及化学成分等学科的研究, 论述了世界蒿属植物的系统分类及其种属地理、历史地理和区系地理.  相似文献   

15.
Rhizopogon (Basidiomycota, Boletales) is a genus of hypogeous fungi that form ectomycorrhizal associations mostly with members of the Pinaceae. This genus comprises an estimated 100(+) species, with the greatest diversity found in coniferous forests of the Pacific northwestern United States. Maximum parsimony analyses of 54 nuclear ribosomal DNA internal transcribed spacer (ITS) sequences including 27 Rhizopogon and 10 Suillus species were conducted to test sectional relationships in Rhizopogon and examine phylogenetic relationships with the closely related epigeous genus, Suillus. Sequences from 10 Rhizopogon type collections were included in these analyses. Rhizopogon and Suillus were both monophyletic. Rhizopogon section Rhizopogon is not monophyletic and comprised two clades, one of which consisted of two well supported lineages characterized by several long insertions. Rhizopogon sections Amylopogon and Villosuli formed well supported groups, but certain species concepts within these sections were unresolved. Four species from section Fulviglebae formed a strongly supported clade within section Villosuli. Subgeneric taxonomic revisions are presented.  相似文献   

16.
武春生  方承莱 《昆虫学报》2009,52(5):561-566
系统整理了中国眉刺蛾属的全部种类,共9种及1亚种,包括1新种--黄眉刺蛾Narosa pseudopropolia Wu et Fang及1新纪录种--齐眉刺蛾N. propolia Hampson。编制了本属中国已知种的检索表,提供了成虫和外生殖器特征照片。新种模式标本保存在中国科学院动物研究所。  相似文献   

17.
The four related genera: Ainsworthia Boiss., Tordylium L., Synelcosciadium Boiss. and Mandenovia Alava are revised. Data are presented from detailed gross morphology, mericarp surface features and anatomy, and palynology.
The results show: (1) Ainsmorthia and Synelcosciadium are congeneric with the genus Tordylium, and that Mandenovia is a good monotypic genus; (2) Tordylium persicum is synonymous with 7. cappadocicum and 7. aegaeum with 7. pestalozzae; (3) the genus Tordylium is best divided into subgenus Tordylium (including Synelcosciadium) and subgenus Ainsworthia (Boiss.) Drude. The latter is divided into section Condylocarpus (Hoffm.) DC, section Hasselquistia (L.) Boiss. and section Univittata Drude.
A new species of Tordylium is described, and two new combinations made. A taxonomic treatment of the genus 'Tordylium', together with a key to the species, is given.  相似文献   

18.
用matK序列分析探讨木兰属植物的系统发育关系   总被引:2,自引:0,他引:2  
用木兰科Magnoliaceae 57种植物的matK基因序列构建了该科的系统发育分支图。结果表明: (1)木兰属Magnolia L.是一个因为性状的趋同演化而建立的多系类群; (2)木兰亚属subgen. Magnolia和玉兰亚属subgen. Yulania (Spach) Reichenb.亲缘关系较远, 支持将后者从该属中分出建立玉兰属Yulania Spach, 木兰亚属作为木兰属保留; (3)木兰亚属的sect. Splendentes Dandy ex Vazquez组与皱种组sect. Rytidospermum Spach的两个美洲种M. macrophylla Michaux和M. dealbata Zucc.亲缘关系较近, 荷花玉兰组sect. Theorhodon Spach与常绿组sect. Gwillimia DC.的亲缘关系较近; (4)盖裂木属Talauma Juss.可以成立, 而其分布于亚洲的Blumiana Blume组可归入木兰属; (5)拟单性木兰属Parakmeria Hu &; Cheng、华盖木属Manglietiastrum Law以及单性木兰属Kmeria (Pierre) Dandy形成一个单系群, 与玉兰亚属和含笑属Michelia L.的亲缘关系较近。花的着生位置不足以作为木兰科的分族依据, 含笑族Michelieae和木兰族Magnolieae的特征及其界定应做修改。将玉兰亚属从木兰属分出后, 木兰属与含笑属无性状交叉,成为两个区别明显的属。  相似文献   

19.
20.
Species of the genus Antirrhinum (Veronicaceae) provide excellent opportunities for research on plant evolution given their extensive morphological and ecological diversity. These opportunities are enhanced by genetic and developmental data from the model organism Antirrhinum majus. The genus Antirrhinum includes 15 New World species in section Saerorhinum and 21 Old World species in sections Antirrhinum and Orontium. Phylogenetic analyses of sequences of the internal transcribed spacer region (ITS) of nuclear ribosomal DNA were conducted for 19 Antirrhinum species, including all species from the New World, and 13 related genera in the tribe Antirrhineae. These analyses confirm the monophyly of Antirrhinum given the inclusion of the small genus Mohavea and exclusion of A. cyathiferum. The New World species, all of which are tetraploid, form a clade that is weakly supported as sister to the Old World sect. Orontium. The Old World species in sect. Antirrhinum form a well-supported clade that is sister to the remainder of the genus. In addition, both molecular and morphological data are used in the most comprehensive effort to date focused on recovering the phylogenetic relationships among the extremely diverse species in section Saerorhinum.  相似文献   

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