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1.
张秀英  范亚文 《植物研究》2005,25(2):186-191
利用7种随机引物对分布于黑龙江省不同区域蹄盖蕨科中的蹄盖蕨属,羽节蕨属及冷蕨属三属的遗传多样性进行了初步分析,对蹄盖蕨科各种基因组的DNA进行了PCR扩增,并对其RAPD谱带进行了统计处理,得出不同区域种类的多态位点百分率,结果表明蹄盖蕨科植物具有较高水平的遗传变异,其种类的分布对周围环境变化有着较强的适应能力。利用Shannon指数和Nei指数对其分析,确定了三属之间的属内种间的亲缘关系:蹄盖蕨属的大部分变异仍存在于种源内;冷蕨属中的冷蕨和山冷蕨种类之间具有一定的遗传变异;羽节蕨属中,欧洲羽节蕨和羽节蕨种间有较大的遗传变异。  相似文献   

2.
The spores of all specimens of Cystopteris in the Herbarium of the Institute of Botany, Academea Sinica have been examined under light microscope. The result of the survey shows for the first time that the distribution of Cystopteris dickieana Sim with non-spiny spores is also quite wide-spread in China, including provinces Xinjiang, Xizang, Qinghai, Gansu, Sichuan, Hebei in northwestern China and Tibetan plateau. The range of altitude for this species varies from 1800 to 5400(5600) m, but C. fragilis (L.) Bernh. from 210 to 4600 m. The differences in the altitudinal distribution range seem to suggest that C. dickieana is more tolerant of cold conditions than C. fragilis. There are also variations in size and ornamentation of the spores in each of the two species. Their ploidy and relationships await futher cytogenetical study from livingmaterials.  相似文献   

3.
采自海南省文昌市文昌镇一个蓼科蓼属植物新变种,与火炭母(Polygonum chinenseLinn.var.chinense)相比较,其主要特点是茎匍匐,叶具大斑点,命名为铺地火炭母(Polygonum chinenseLinn.var.procumbensZ.E.Zhao et J.R.Zhao)。  相似文献   

4.
羊草与其主要伴生种竞争与共存的格局分析   总被引:4,自引:3,他引:4  
在羊草种群与其它植物种群的交错区,应用频度、格避形式,格局强度指数对羊草及其主要伴生种之间的共存格局进行了分析。结果表明,羊草及其主要伴生种的格局呈多样化,集聚格局形式是羊草抵御外来物种入侵,或者是自身扩散的一种对策,羊草与其主要伴生种之间存在竞争与共存作用,羊草与芦苇之间通过拮抗作用实现竞争与共存,羊草与鸡儿肠通过竞争而实现共存,光稃茅香,碱茅以营养繁殖策略实现与羊草竞争,指子茅的生长受羊草竞争的抑制。  相似文献   

5.
Three new species of ferns are described from Mexico:Athyrium tripinnatum, Cystopteris millefolia, andPolypodium praetermissum.  相似文献   

6.
Vesicular cavities in the lava fields of Northern Iceland communicate by small openings with the ground surface. Aeolian sediments, called the Icelandic Ioess, deposit over the bottom of these cavities, together with the reduced light intensity and equable microclimate, create specific biotopes occupied by sciophilous bryophytes andCystopteris fragilis. A new association within the allianceCtenidion Stefureac 1941—Cystopteri-Distichietum capillacei Bla?ková ass. nova— is described in the present paper.  相似文献   

7.
8.
通过对2013年10月在山东省泰安市山东农业大学校园采集到的枸杞白粉病进行病害症状观察和病原菌形态学鉴定,确定引起枸杞白粉病的病原菌为穆氏节丝壳Arthrocladiella mougeotii。节丝壳属为山东省新记录属,枸杞白粉病为山东省新病害。  相似文献   

9.
目的:建立北柴胡不定根培养体系,明确茉莉酸甲酯(MeJA)处理对北柴胡不定根中柴胡皂苷含量积累的影响。方法:利用固体和液体相结合的组织培养技术培养北柴胡不定根;分别以不同浓度的MeJA处理不定根不同时间,利用HPLC测定处理后不定根中柴胡皂苷含量的积累变化。结果:培养了北柴胡不定根;MeJA处理对北柴胡不定根中柴胡皂苷含量的积累有明显促进作用,当MeJA浓度为200μmol/L时,柴胡皂苷含量最高,为0.45%;以200μmol/L MeJA处理北柴胡不定根26 d时,柴胡皂苷含量最高,为0.51%。结论:北柴胡不定根培养结合MeJA诱导,可做为柴胡皂苷次生代谢合成途径及其积累规律研究的有效技术体系。  相似文献   

10.
Lycium amarum sp. nov. L. Q. Huang is described based on its general morphology and pollen micromorphology, which were compared with closely related Lycium species. The phylogenetic relationships among the new species and closely related Lycium species belonging to the tribe Lycieae were investigated based on the DNA sequence data of the granule‐bound starch synthase (GBSSI) gene. Morphologically, L. amarum is similar to L. chinense Mill. sharing lanceolate or linear‐oblanceolate leaves, three‐lobed calyx, villous ring slightly above the filament base, and adjacent corolla tube, however, L. amarum may be diagnosed by its prominent tubercles at the base of spines, thinly leathery leaves, and a two‐tine crack on the tip of calyx lobes. According to our results, the new species is close to L. barbarum L., L. chinense, L. dasystemum Pojark, and L. yunnanense Kuang & Lu.  相似文献   

11.
不同种群密度羊草生态场梯度及其变化特征   总被引:7,自引:2,他引:7  
通过对植物个体与种群生态场定位实验研究,提出了生态场梯度的概念,并给出了植物与羊草个体生态场梯度的模型,植物生态场的场梯度是,生态场中生态势沿任意方向的变化率。羊草个体生态场梯度同羊草种群密度相关。  相似文献   

12.
Summary

The discovery of the fern Cystopteris dickieana Sim in Kincardineshire (the type locality of the species) during the mid- nineteenth century, an its supposed extirpation only twelve years after being first brought to public notice is described. The background to its apparent disappearance and subsequent reappearance are examined.  相似文献   

13.
红花檵木与檵木花数性表型变异研究   总被引:6,自引:0,他引:6  
红花木与木花的数性结构有很大差异 ,木 4数性花占 96 2 %(花瓣、雄蕊、退化雄蕊、萼片均为 4数 ) ;野生红花木 4数性花约占 5 0 %;红花木栽培类型以 5数性花居多 ,不同类型品种花的数性结构亦有差异 ,总体变异规律为 :近期栽培品种双面红类 5数性花 >中期栽培品种透骨红类 >早期栽培品种嫩叶红类。利用花的数性表型变异探讨了品种的演化历史和新品种选育的前景。  相似文献   

14.
松嫩平原羊草草地土壤水盐运动规律的研究   总被引:16,自引:0,他引:16       下载免费PDF全文
 羊草草地植物群落的分布与土壤水盐运动有着十分密切的关系。研究结果表明,羊草、拂子茅、獐毛和角碱蓬群落的土壤饱和导水率分别为0.0586cm·h-1,0.0567cm·h-1,0.0175cm·h-1和0.0004cm·h-1。当土壤含水量相同时,角碱蓬群落下土壤水吸力高于羊草群落。在相同的土壤水吸力范围内,角碱蓬群落下土壤非饱和导水率高于羊草群落。因此,角碱蓬群落在春季干旱时,土体内上行水流的数量和强度远远大于羊草群落。夏季降水集中时,角碱蓬群落下土体内下行水流又远远小于羊草群落。造成土体上部甚至表层的盐分积累。  相似文献   

15.
永瓣藤的分布现状及其保护   总被引:10,自引:0,他引:10  
本文从自然环境、分布特征、种群数量和种群繁殖等方面研究了我国珍稀特有植物永瓣藤(Monimopetalum chinense)的分布和保护现状, 并从引种栽培、种子繁殖和无性繁殖等方面总结了近年来对永瓣藤进行迁地保存的初步研究结果, 最后提出了相应的保护建议。  相似文献   

16.
戚秋慧  盛修武  姜恕 《生态学报》1983,3(4):333-340
群落光合生态的研究是植物物质生产研究的基础之一。通过群落光合速率及其与环境条件关系的研究,阐明制约光合的有关变量,就可以为估算植物的潜在生产力提供依据。为此进行群落光合特性以及与外界环境关系的研究,是群落光合生态研究中不可缺少的一个环节。 有关群落光合日变化及其与环境条件相互关系的研究已有不少报道(户刈义次,1979;Singh et al.,1980;Migasaka et al.,1978;权永忍,1980),但以作物方面的研究较为突出,而对天然群落的研究较少。 我们根据同化箱的气体交换法原理(群落光合研究的方法很多),试制了一台简易光合测定车。利用这个装置,于1981年7、8月间,对内蒙锡盟白音锡勒地区的羊草草原群落进行  相似文献   

17.
The Hoabinhian is a distinctive lithic techno-complex of mainland and Island Southeast Asia. Knowledge of its relationships with key patterns of technological change at a global scale has progressed over the last two decades. However, our understanding of the Hoabinhian as an indicator of evolution during Prehistory can be substantially enhanced by examining its regional and chronological variability. Here, we present the characteristics of original Hoabinhian artefacts found in a new open-air site at Houay Pano, near Lak Sip (Luang Prabang province, Laos). This technological study of such a classic assemblage, including sumatraliths dated to 5.5 ± 0.6 ka, is a major contribution to Laotian prehistory and our understanding of the tempo-spatial variability of the Hoabinhian techno-complex.  相似文献   

18.
草地植物群落地上生物量非破坏性估测方法的探讨   总被引:2,自引:0,他引:2       下载免费PDF全文
 羊草群落的高度和盖度与地上生物量存在良好的复相关关系(R=0.9316),所获多元回归方程可用于该群落地上生物量的估测。通过对羊草群落、羊草+杂类草群落和贝加尔针茅群落植冠红光(0.63—0.69μm)和近红外辐射(0.76—0.90μm)反射率实测数据的分析,表明这些群落的光谱反射率比IR、IR/R和VI与地上生物量呈高度的指数相关关系,其中由VI和IR/R所获各群落不同生长时期地上生物量回归模型的估测效果较好。  相似文献   

19.
The northeast region of India, considered as 'hot spot' of biodiversity, having unique ecological environment with hot and high-humidity conditions, has given rise to the world's hottest chilli, 'Bhut Jolokia', which is at least two times hotter than Red Savina Habanero in terms of Scoville heat units (SHU). This study was undertaken to determine the distinctiveness of 'Bhut Jolokia' from Capsicum frutescens or Capsicum chinense through sequencing of the ribosomal RNA (rRNA) gene-internal transcribed ((ITS) region along with its phylogenetic analysis. Although a compensatory base change (CBC) in the ITS2 region was not observed between the closely related species of C. frutescens and C. chinense when compared with Bhut Jolokia; phylogenetic analysis using ITS1, 5.8S and ITS2 sequences indicated a distinct clade for all the accessions of 'Bhut Joloikia', while C. frutescens and C. chinense occupied discrete lineages. Further, a unique 13-base deletion was observed in all the representative accessions of 'Bhut Jolokia', making it distinct from all other members within the genus and beyond. The degree of genetic variations along with its extreme pungency might be related to ambient environmental factors of northeastern India.  相似文献   

20.
王德利  祝廷成 《生态学报》1996,16(2):121-127
本文通过对羊草种群与个体的定位观测与理论分析,给出了描述植物生态属性质的场特征函数──生志势和场梯度的定义,建立了羊草地上部生态场的生态势和场梯度模型。应用实验观测数据进行了模型运算,分析了草草地上部生态场随作用距离改变的生态势与场梯度变化规律。结果表明,羊草地上部场势与场源植物的相对生长速率、资源利用效力以及种群密度相失,场梯度能刻划生态势的空同变化速率,生态势和场梯度均有季节性变化特征。  相似文献   

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