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1.
植物有效利用土壤磷特性的遗传学研究进展   总被引:9,自引:0,他引:9  
植物有效利用土壤磷的特性是一系列形态、生理、生化特性的综合反映,包括植物根系活化土壤中难溶性磷、对磷的吸收、转运、分配与利用等。而这些特性又均受控于特定的遗传机制。本文简要概述该特性的细胞遗传学、数量遗传学的研究进展。  相似文献   

2.
荷叶铁线蕨为三峡库区珍稀濒危植物 ,已被国家列为二级保护植物。本文较系统地综述了荷叶铁线蕨的生物学特性 ,包括其形态特征、生长特性、地理分布、生态学特性和群落学特性 ,分析了荷叶铁线蕨濒危的可能原因 ,并提出了保护措施  相似文献   

3.
[目的]对从酸马奶中分离出来的10株乳酸菌进行鉴定和生理生化特性研究,为工业生产筛选特性优良的菌种.[方法]通过形态学观察、生理生化特性、分子生物学特性及其对致病菌抑制作用的研究对其进行鉴定,并筛选特性优良菌株.[结果]10株乳酸菌分别为2株Lactobacillus plantarum、2株Enterococcus villorum、2株Enterococcus dispar、3株Enterococcus durans和1株Enterococcus raffinosus;其对Staphylococcus aureus、Escherichia coli和Enteritidis bacillus有不同程度的抑制作用.[结论]菌株HZ24、HZ25具有良好的生物学特性和益生功能,可以应用到食品发酵工业生产中.  相似文献   

4.
太子参生物学特性的研究   总被引:5,自引:0,他引:5  
报道了江苏地道药材太子参Pseudostellaria heterophylla (Miq.)Pax ex Pax et Hoffm的生物学特性,包括形态特征、主要分布区和主产区、生态特性、种子萌发特性、生长发育特性等,为进行太子参的规范化栽培提供科学依据。  相似文献   

5.
对我国特有的珍稀濒危植物独叶草的生物学特性,包括其形态特征、生长特性、生境特点、群落学特性和地理分布进行了较系统的综述,分析了独叶草濒危的可能原因,并提出了一些保护措施.  相似文献   

6.
【背景】鄂尔多斯地区传统自然发酵苦菜风味和作用独特,但目前尚无关于发酵苦菜中乳酸菌种类及其生物学特性研究的报道。【目的】获得适用于工业化生产特性优良的乳酸菌。【方法】通过测定总酸度筛选高产酸菌株,并进行形态学鉴定、生理生化特性研究,以及16S rRNA基因片段分析。【结果】经鉴定5株高产酸的菌株均为植物乳杆菌,生长温度范围宽,并且具有耐酸、耐碱、耐盐、耐热的特性。【结论】试验菌株具有优良的生理特性和潜在的益生特性,可用于食品工业的生产。  相似文献   

7.
干旱胁迫对植物气孔特性影响研究进展   总被引:5,自引:0,他引:5  
综述干旱胁迫对植物叶片气孔特性的影响,从气孔大小、气孔密度、气孔导度等方面概括植物气孔对干旱胁迫的响应,分析植物气孔特性与其抗旱性的关系,并对气孔特性的研究方向进行展望。  相似文献   

8.
葡激酶的研究进展   总被引:1,自引:0,他引:1  
本文综述了葡激酶的生化特性、溶栓特性、免疫原性和临床应用方面的研究进展。  相似文献   

9.
芽用绿豆品种子粒性状及其豆芽生理特性研究   总被引:1,自引:0,他引:1  
以21份芽用绿豆品种为材料,研究了种皮色泽、种皮比重等种皮性状、百粒重等物理特性、发芽期间的生物产量变化规律、种子吸水速率等生理特性以及绿豆芽产量、豆芽形态特征和感官品质等芽用特性指标,分析了各项物理生理特性指标与芽用特性指标的相关性。结果表明,芽用绿豆品种的产出比、下胚轴粗和下胚轴长等特性指标范围分别为111.7-143.2、7.21-11.79和0.245-0.353;品种的种皮色泽与绿豆芽生物产量、绿豆芽下胚轴粗及下胚轴长无显著相关,而与品种的百粒重呈显著相关性(P<0.05);百粒重与绿豆芽生物产量呈显著负相关(P<0.05);下胚轴粗与绿豆芽生物产量呈极显著负相关(P<0.05);初步建立了适用于评价绿豆品种芽用特性的指标:豆芽产量、下胚轴粗和下胚轴长,筛选出具有较好芽用特性的绿豆品种MB01、MB07、MB19和MB45。  相似文献   

10.
以移动的正弦光栅作为刺激,用玻璃微电极记录以冰冻法毁损皮层17、18、19区和外侧上雪氏回(LS)区后的猫外膝体的单细胞反应,测定了了579个细胞的方位调谐特性.另外还在视觉剥夺猫外膝体测定了344个细胞的方位调谐特性.与正常猫相似,去视皮层猫和视觉剥夺猫外膝体的少数细胞(约占10%)具有非寻常的方位调谐特性,包括具蝴蝶形调谐曲线的方位调谐特性、双调谐(Bimodal)的方位调谐特性和最优方位随刺激空间频率的不同而变化的方位调谐特性。结果表明,外膝体的非寻常的方位调谐特性并非主要由皮层下行投射所致,而是主要与先天遗传因素有关。  相似文献   

11.
林有润 《植物研究》2002,22(3):341-365
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。  相似文献   

12.
We review current knowledge of the most abundant sugars, sucrose, maltose, glucose and fructose, in the world's major crop plants. The sucrose‐accumulating crops, sugar beet and sugar cane, are included, but the main focus of the review is potato and the major cereal crops. The production of sucrose in photosynthesis and the inter‐relationships of sucrose, glucose, fructose and other metabolites in primary carbon metabolism are described, as well as the synthesis of starch, fructan and cell wall polysaccharides and the breakdown of starch to produce maltose. The importance of sugars as hormone‐like signalling molecules is discussed, including the role of another sugar, trehalose, and the trehalose biosynthetic pathway. The Maillard reaction, which occurs between reducing sugars and amino acids during thermal processing, is described because of its importance for colour and flavour in cooked foods. This reaction also leads to the formation of potentially harmful compounds, such as acrylamide, and is attracting increasing attention as food producers and regulators seek to reduce the levels of acrylamide in cooked food. Genetic and environmental factors affecting sugar concentrations are described.  相似文献   

13.
中国昆虫染色体研究现状与展望   总被引:12,自引:1,他引:12  
简要叙述了中国昆虫染色体研究的现状,包括研究涉及的昆虫类群、核型分析结果、研究方法和手段、染色体有丝分裂、减数分裂、染色体形态变异、结构变异和数量变异等。我国学者对昆虫染色体研究从20世纪30年代开始,迄今已对蜉蝣目、蜚蠊目、直翅目、半翅目、同翅目、鞘翅目、鳞翅目、双翅目、蚤目和膜翅目等10目481种昆虫的核型进行了研究,主要集中在蝗虫、蝽类、蚜虫、蚕类、果蝇、摇蚊及实蝇等。在染色体行为方面的研究主要有:蚕类和果蝇等有丝分裂;蜚蠊类、蝗类、蝽类和蚕类的减数分裂及性别决定机制;部分昆虫的联会复合体分析。染色体结构变异的研究主要集中在果蝇和蚊类昆虫的唾腺染色体;果蝇的B染色体;蚕类和蚊类昆虫染色体的缺失、易位和倒位等变异;蚕蛾类的数量变异。研究结果多应用于昆虫系统分类和进化的探讨,揭示昆虫遗传与变异规律。通过与国外研究成果对比,提出昆虫染色体研究的必要性,并对我国未来昆虫染色体研究进行了展望。  相似文献   

14.
State and management of wetlands in Bangladesh   总被引:1,自引:0,他引:1  
Wetlands are a vital link between land and water in Bangladesh. A majority of the people of Bangladesh are critically dependent on wetlands. In this paper, the values of wetlands, causes and effects of wetlands degradation, as well as the present wetlands management approach, are analyzed and recommendations for wetlands management are suggested based on participatory rural appraisal (PRA), field visit, personal experience, and existing literature and information. Wetlands play a crucial role in maintaining the ecological balance of ecosystems, but wetlands habitat of Bangladesh is under constant threat due to increase of population, intensive agriculture, overfishing, siltation, pollution, ill-planned infrastructures, lack of institutional coordination, lack of awareness, etc. As a result biodiversity is reducing, many species of flora and fauna are threatened, wetlands-based ecosystem is degenerating, and the living conditions of local people are deteriorating as livelihoods, socioeconomic institutions, and cultural values are affected. Wetlands management is not addressed separately in water management activities of Bangladesh. In order to balance human needs and wetlands conservation, a mainly community-based wetlands management approach has been taken in Bangladesh, but this is not enough to prevent the degradation of wetlands. Therefore, Bangladesh now needs a comprehensive strategy combining political, economic, social, and technological approaches to stop further degradation of wetlands. Therefore, wetlands management should be incorporated into a system of integrated land and water use and, indeed, into the socioeconomic system of the country. Policies, strategies, and management plans for sustainable use and conservation of wetlands of Bangladesh must be based on solid knowledge and understanding of their ecological and socioeconomic functions and processes.  相似文献   

15.
16.
Microbes colonise all multicellular life, and the gut microbiome has been shown to influence a range of host physiological and behavioural phenotypes. One of the most intriguing and least understood of these influences lies in the domain of the microbiome's interactions with host social behaviour, with new evidence revealing that the gut microbiome makes important contributions to animal sociality. However, little is known about the biological processes through which the microbiome might influence host social behaviour. Here, we synthesise evidence of the gut microbiome's interactions with various aspects of host sociality, including sociability, social cognition, social stress, and autism. We discuss evidence of microbial associations with the most likely physiological mediators of animal social interaction. These include the structure and function of regions of the ‘social' brain (the amygdala, the prefrontal cortex, and the hippocampus) and the regulation of ‘social’ signalling molecules (glucocorticoids including corticosterone and cortisol, sex hormones including testosterone, oestrogens, and progestogens, neuropeptide hormones such as oxytocin and arginine vasopressin, and monoamine neurotransmitters such as serotonin and dopamine). We also discuss microbiome‐associated host genetic and epigenetic processes relevant to social behaviour. We then review research on microbial interactions with olfaction in insects and mammals, which contribute to social signalling and communication. Following these discussions, we examine evidence of microbial associations with emotion and social behaviour in humans, focussing on psychobiotic studies, microbe–depression correlations, early human development, autism, and issues of statistical power, replication, and causality. We analyse how the putative physiological mediators of the microbiome–sociality connection may be investigated, and discuss issues relating to the interpretation of results. We also suggest that other candidate molecules should be studied, insofar as they exert effects on social behaviour and are known to interact with the microbiome. Finally, we consider different models of the sequence of microbial effects on host physiological development, and how these may contribute to host social behaviour.  相似文献   

17.
张淑梅  李微  李丁男 《生物多样性》2022,30(6):22038-192
为给辽宁植物多样性保护提供本底数据, 更准确地评价植物濒危及保护等级, 以及更好地给农学、林学、生态学、系统学等研究提供可靠的基础性数据, 本文首次将几代人在辽宁境内发现的高等植物进行汇总、编目, 包括苔藓植物和维管束植物。苔藓植物根据正式发表的文献和中国科学院沈阳应用生态研究所东北生物标本馆(IFP)馆藏采自辽宁省全域的苔藓植物标本编制。维管束植物主要根据5个方面的信息整理: 作者多年野外调查的一手资料、文献、同行交流、公众提供信息、标本等。编目内容包括辽宁省高等植物总名录、辽宁省栽培植物名录、辽宁省外来植物名录、辽宁省仅有栽培植物的科属目录、辽宁省仅有外来植物的科属目录; 编目中涉及的物种均有科属地位、中文名、拉丁名、生境、产地(县级), 总名录中附有每个物种的信息凭证, 包括标本信息、文献信息或照片依据。本编目共计收录植物254科1,176属3,241种73亚种447变种119变型。其中, 苔藓植物为辽宁地区首次披露名录信息, 计83科205属491种4亚种7变种(含藓类52科156属373种1亚种5变种, 苔类29科46属114种3亚种2变种, 角苔类2科3属4种)。维管束植物虽非首次披露名录信息, 但与以往发布的维管束植物名录相比, 本次收录的种类数最多, 计171科971属2,750种69亚种440变种119变型(含石松类植物2科3属13种, 蕨类植物17科39属83种2亚种7变种, 裸子植物5科19属47种1亚种13变种2变型, 被子植物147科910属2,607种66亚种420变种117变型)。经统计, 辽宁省所有苔藓植物均为本土野生植物。维管束植物中, 野生植物计149科741属2,077种62亚种378变种93变型(含石松类植物2科3属13种, 蕨类植物17科39属83种2亚种7变种, 裸子植物4科8属12种6变种1变型, 被子植物145科133属1,969种60亚种365变种92变型), 栽培植物计104科390属673种7亚种62变种26变型(含裸子植物5科17属35种1亚种7变种1变型, 被子植物99科373属638种6亚种55变种25变型); 本土植物计158科796属2,235种65亚种421变种116变型(含石松类植物2科3属13种, 蕨类植物17科39属83种2亚种7变种, 裸子植物5科14属29种12变种2变型, 被子植物134科740属2,110种63亚种402变种114变型), 外来植物计88科316属515种4亚种19变种3变型(含裸子植物3科10属18种1亚种1变种, 被子植物85科306属497种3亚种18变种3变型)。本编目仅是辽宁省高等植物的阶段性汇总, 尚需要根据野外工作的拓展和研究工作的深入不断完善。  相似文献   

18.
The insect orders Megaloptera and Neuroptera are closely related members of the superorder Neuropterida, a relict lineage of holometabolous insects that also includes the Raphidoptera. Megaloptera, composed of the families Sialidae and Corydalidae (including subfamilies Chauliodinae and Corydalinae), has fully aquatic larvae that occur in a wide variety of lotic and lentic habitats, including temporary streams. In total, 2 of 17 families of Neuroptera have aquatic larvae: Nevrorthidae live in the benthos of fast-flowing streams and Sisyridae reside on freshwater sponges. A third family of Neuroptera, Osmylidae, contains some water-dependent species that reside under leaves and rocks along the margins of waterbodies. We recognize 328 extant, described species of Megaloptera (composed of 116 species of Chauliodinae, 131 species of Corydalinae, and 81 species of Sialidae) and 73 species of aquatic Neuroptera (composed of 12 species of Nevrorthidae and 61 species of Sisyridae). Additionally, we estimate that 45 species of Osmylidae are water-dependent, although the ecology of this group is poorly understood. Chauliodinae and Corydalidae are both found in the New World, the Oriental region, and South Africa, but are absent from Europe, the Middle East, Central Asia, tropical Africa, and boreal regions. Chauliodinae is quite speciose in Australia, whereas Corydalinae is absent. Sialidae is most speciose in temperate regions, and is absent from tropical Africa and portions of the Oriental region. Sisyridae and Osmylidae are nearly cosmopolitan, but the relict family Nevrorthidae is limited to Japan, the Mediterranean, and Australia. The discovery of many new species in recent years, particularly among Corydalidae in the Neotropics and China, suggests that our knowledge of aquatic neuropterid diversity is far from complete. Guest editors: E. V. Balian, C. Lévêque, H. Segers and K. Martens Freshwater Animal Diversity Assessment  相似文献   

19.
Abstract

An introduction to the nomenclature and concept of “Romanowsky stains” is followed by a brief account of the dyes involved and especially the crucial role of azure B and of the impurity of most commercial dye lots. Technical features of standardized and traditional Romanowsky stains are outlined, e.g., number and ratio of the acidic and basic dyes used, solvent effects, staining times, and fixation effects. The peculiar advantages of Romanowsky staining are noted, namely, the polychromasia achieved in a technically simple manner with the potential for stain intensification of “the color purple.” Accounts are provided of a variety of physicochemically relevant topics, namely, acidic and basic dyeing, peculiarities of acidic and basic dye mixtures, consequences of differential staining rates of different cell and tissue components and of different dyes, the chemical significance of “the color purple,” the substrate selectivity for purple color formation and its intensification in situ due to a template effect, effects of resin embedding and prior fixation. Based on these physicochemical phenomena, mechanisms for the various Romanowsky staining applications are outlined including for blood, marrow and cytological smears; G-bands of chromosomes; microorganisms and other single-cell entities; and paraffin and resin tissue sections. The common factors involved in these specific mechanisms are pulled together to generate a “universal” generic mechanism for these stains. Certain generic problems of Romanowsky stains are discussed including the instability of solutions of acidic dye–basic dye mixtures, the inherent heterogeneity of polychrome methylene blue, and the resulting problems of standardization. Finally, a rational trouble-shooting scheme is appended.  相似文献   

20.
On the basis of biosynthsis, distribution of diterpenoid alkaloids as well as morphological evolution of Chinese species L. (Ranunculaceae), chemotaxonomy of the genus Aconitum is discussed: 1, Subgen. Lycoctonum, containing lycoctonine-type alkaloids and Subgen. Aconitum containing aconitine-type alkaloids, were probably differetiated at the early stage of evolution of the genus Aconitum and evolved respectively in their own ways. 2, In Subgen. Aconitum: (1) Ser. Bullatifolia, containing mainly atisine-, veatchine-type alkaloids, and amino, alcohol and ester base of aconitine-type, and distributed in Hengduan Mountain and Jingsha River valley, where is the centre of modern differentiation of species of Aconitum, is probably a series from which Chinese species of the genus Aconitum were derived; (2) Ser. Inflata, containing mainly aconitine, mesaconitine and bypaconitine, is an advanced group; (3) Ser. Grsndituberosa, containing mainly aconitine and songorine, is related to Ser. Bulatifolia; (4) Ser. stylosa and Ser. volubilia, containing mainly yunaconitine and other anisyl ester alkaloids form another advanced branch. 3, Ser. Tangutica and A. naviculare of Ser. Rotaundifolia, containing atisine and lactone-type alkaloids may be a specialized group in high mountains and have occurred at early stage of evolution of the genus Aconitum. 4, Subgen. Gymnaconitum, containing atisine-type alkaloids and amino alcohol of aconitine type, may als be a specialized group in high mountains. 5, A. franchetii Finet. et Gagnep. mainly containing ester bases of aconitine-typeand closed to A. chasmanthum Stapf, is best placed into Ser. Ambigua.  相似文献   

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