我国植物食用色素资源开发利用评价

古代人们使用的着色剂都是天然产品,除少数矿物颜料外,主要是植物源色素。我国古代就有以红曲米作为着色剂利用的习惯;在高等植物方面,生产蓝色、黄色、绿色的颜料的高等植物种类不少,大多沿用至今。自19世纪中叶以后,人工合成色素以着色牢固、鲜艳、成本低廉等特点,迅速占领了印染、食品等许多行业,但20世纪60年代以后,许多研究表明,一般合成色素都有程度不等的毒性,特别是化学结构含偶氮型的色素有可能在人体内成为致癌物。同时,在色素合成的过程中,还有可能污染有重金属及其他有害物质。因此,合成色素越来越使人们感到不安全。从20世纪50年代的100多种人工合成色素用于食品着色,到20世纪末,已有60~70余种被禁用了,而植物食用色素在食品行业中成为主要着色剂。近年来又涌现出多种有价值的高等植物源色素,我们选择其主要一些植物种类做些介绍,供有关方面参考。     

Reflections on 'plant neurobiology'

Plant neurobiology, a new and developing area in the plant sciences, is a meeting place for scientists concerned with exploring how plants perceive signs within their environment and convert them into internal electro-chemical ('plant neurobiological') signals. These signals, in turn, permit rapid modifications of physiology and development that help plants adjust to changes in their environment. The use of the epithet 'neurobiology' in the context of plant life has, however, led to misunderstanding about the aims, content, and scope of this topic. This difficulty is possibly due to the terminology used, since this is often unfamiliar in the context of plants. In the present article, the scope of plant neurobiology is explored and some of analogical and metaphorical aspects of the subject are discussed. One approach to reconciling possible problems of using the term 'plant neurobiology' and, at the same time, of analysing information transfer in plants and the developmental processes which are regulated thereby, is through Living Systems Theory (LST). This theory specifically directs attention to the means by which information is gathered and processed, and then dispersed throughout the hierarchy of organisational levels of the plant body. Attempts to identify the plant 'neural' structures point to the involvement of the vascular tissue - xylem and phloem - in conveying electrical impulses generated in zones of special sensitivity to receptive locations throughout the plant in response to mild stress. Vascular tissue therefore corresponds, at the level of organismic organisation, with the informational 'channel and net' subsystem of LST.     

濒危植物小勾儿茶伴生群落特征研究

从植物生活型、群落垂直结构、物种多样性以及群落稳定性4个方面研究小勾儿茶伴生群落特征,分析小勾儿茶在该生境幸存的原因。生活型谱反映出生境温热高湿且四季分明的亚热带气候特点;小勾儿茶处于群落顶层,能够获得充足的阳光;群落结构稳定、物种丰富。小勾儿茶的数量已极为稀少,应采取调查、保护和扩繁3种主要措施扩大其种群数量,即：(1)加大力度在相似的生境中寻找小勾儿茶;(2)对其生境加大保护力度;(3)开展种子生理方面的研究,探索有效的发芽途径,同时用组培的方法繁殖幼苗。     

植物微生物组的功能及应用研究进展

健康的植物中生活着多种多样但分类学结构不同的微生物群落,它们在所有可接触到的植物组织中定殖.这些微生物群落赋予植物宿主健康优势,包括促进宿主植物生长、营养吸收、抗逆性和对病原菌的抵抗力等.植物菌群及其相互作用具有高度的多样性,多种因素决定着群落的组成和功能.虽然从19世纪开始植物菌群就被人们所认识,但对其功能及应用的相...     

Symbolic plant(s) of the Olympic Games

The victors of the Olympic Games in ancient Greece were awarded crowns made of olive branches. In Antiquity, the symbolism of plants was related to myths, properties, aesthetic values, and civilization. Theophrastus first classifies and identifies plants, and gathers information about them, in his classic books (4th century BC). Symbolic plants are native to the Mediterranean region and they exhibit some convergent behaviour with respect to their functional characteristics. These plants were collected (among other species) by Professor J. Sibthorp and his partners in two botanical journeys in the Levant during the 18th century, and they have been illustrated for Flora Graeca Sibthorpiana.     

植物生态化学计量特征及其主要假说

植物生态化学计量学是生态化学计量学的重要分支, 主要研究植物器官元素含量的计量特征, 以及它们与环境因子、生态系统功能之间的关系。19世纪, 化学家们通过室内实验, 分析了植物器官的元素含量, 开始了对植物化学元素之间关系的探索。如今, 生态学家通过野外采样和控制实验, 探索植物化学元素计量特征的变化规律、对全球变化的响应以及与植物功能属性之间的关系, 促进了植物生态化学计量学的快速发展。该文在概述植物生态化学计量学发展简史的基础上, 综述了19世纪以来该领域的研究进展。首先, 该文将植物生态化学计量学的发展历程概括为思想萌芽期、假说奠基期和理论构建期3个时期, 对各个时期的主要研究进行了简要回顾和梳理。第二, 概述了植物主要器官的化学计量特征, 尤其是陆生植物叶片氮(N)和磷(P)的计量特征。总体上, 全球陆生植物叶片N、P含量和N:P (质量比)的几何平均值分别为18.74 mg∙g^-1、1.21 mg∙g^-1和15.55 (与16:1的Redfield比一致); 在物种或群落水平上, 叶片N和P含量一般呈现随温度升高、降水增加而降低的趋势。不同生活型植物叶片N和P计量特征差异明显, 尤其是草本植物叶片N和P含量高于木本植物, 落叶阔叶木本植物叶片N和P含量高于常绿木本植物。与叶片相比, 细根和其他器官化学计量特征研究较少。第三, 总结了养分添加实验对植物化学元素计量特征的影响。总体上, N添加一般会提高土壤N的可利用性, 使植物器官中N含量和N:P升高, 在一定程度上提高植物生产力; P添加可能会缓解过量N输入导致的N-P失衡问题, 提高植物器官P含量。但是, 长期过量施肥会打破植物器官原有的元素间计量关系, 导致元素计量关系失衡和生产力下降。第四, 梳理总结了植物生态化学计量学的重要理论、观点和假说, 主要包括刻画化学计量特征与植物生长功能关系的功能关联假说、刻画化学计量特征与环境因子关系的环境关联假说或理论以及刻画化学计量特征与植物进化历史关系的进化关联假说。最后, 指出了植物生态化学计量学研究中存在的问题, 展望了10个未来需要重点关注的研究方向。     

Root Colonization by Inoculated Plant Growth-Promoting Rhizobacteria

Certain rhizobacteria referred to as 'plant growth-promoting rhizobacteria' (PGPR) can contribute to the biological control of plant pathogens and improve plant growth. They enhance root development either directly by producing phytohormones, or indirectly by inhibiting pathogens through the synthesis of different compounds. PGPR are likely to be of great interest in sustainable crop protection and have drawn much attention in recent years. However, the use of these bacteria to protect crops sometimes fails because rhizobacteria are unable to recolonize the rhizosphere of inoculated plants. The colonization of roots by inoculated bacteria is an important step in the interaction between beneficial bacteria and the host plant. However, it is a complex phenomenon influenced by many biotic and abiotic parameters, some of which are now apparent. This paper summarises knowledge on rhizosphere colonization by PGPR.     

Mechanism of plant growth promotion by rhizobacteria

Plant growth results from interaction of roots and shoots with the environment. The environment for roots is the soil or planting medium which provide structural support as well as water and nutrients to the plant. Roots also support the growth and functions of a complex of microorganisms that can have a profound effect on the growth anti survival of plants. These microorganisms constitute rhizosphere microflora and can be categorized as deleterious, beneficial, or neutral with respect to root/plant health. Beneficial interactions between roots and microbes do occur in rhizosphere and can be enhanced. Increased plant growth and crop yield can be obtained upon inoculating seeds or roots with certain specific root-colonizing bacteria- 'plant growth promoting rhizobacteria'. In this review, we discuss the mechanisms by which plant growth promoting rhizobacteria may stimulate plant growth.     

Polygenic inheritance of bean mass

Analogies between plants and animals are often a source of confusion in the understanding of sexual reproduction in green plants

The ancient view that plants are non-sexual because they hold a place below animals on the ladder of nature was still held by many scientists in the 1 8th century. Paradoxically, al this time, Linnaeus and others were also postulating the universality of plant sexuality by using analogies with animals to over-extend the slowly emerging experimental evidence about the functions of floral parts. Today's school leavers seem to have similarly diverse views. A lack of school focus on gamete fusion appears to result in a continuing reliance on analogies with animals, and a belief that plants undergo only a qualified version of sexual reproduction. Suggestions for classroom activities to overcome this are offered, and some wider implications are considered.     

Auxin conjugates: their role for plant development and in the evolution of land plants

Auxin conjugates are thought to play important roles as storage forms for the active plant hormone indole-3-acetic acid (IAA). In its free form, IAA comprises only up to 25% of the total amount of IAA, depending on the tissue and the plant species studied. The major forms of IAA conjugate are low molecular weight ester or amide forms, but there is increasing evidence of the occurrence of peptides and proteins modified by IAA. Since the discovery of genes and enzymes involved in synthesis and hydrolysis of auxin conjugates, much knowledge has been gained on the biochemistry and function of these compounds, but there is still much to discover. For example, recent work has shown that some auxin conjugate hydrolases prefer conjugates with longer-chain auxins such as indole-3-propionic acid and indole-3-butyric acid as substrate. Also, the compartmentation of these reactions in the cell or in tissues has not been resolved in great detail. The function of auxin conjugates has been mainly elucidated by mutant analysis in genes for synthesis or hydrolysis and a possible function for conjugates inferred from these results. In the evolution of land plants auxin conjugates seem to be connected with the development of certain traits such as embryo, shoot, and vasculature. Most likely, the synthesis of auxin conjugates was developed first, since it has been already detected in moss, whereas sequences typical of auxin conjugate hydrolases were found according to database entries first in moss ferns. The implications for the regulation of auxin levels in different species will be discussed.     

Neophyten in Mitteleuropa

Neophytes in Central Europe – Success stories of invasive alien plant species Since the 17th century, the introduction of alien plant species has been increasing constantly. They have been introduced intentionally (for example as ornamental garden plants) or accidentally. More than 430 alien species are permanent wild plants in Germany by now, mainly growing in anthropogenic, ruderal habitats without causing any problems. However, some of them build up large, monodominant stands in near‐natural sites. They cause negative impacts on native species diversity, ecosystems or even human health. These species are considered as invasive. They are tough to manage because of their high regenerative capacity and intensive reproduction. Climate change will probably produce more favourable conditions for many of them. Thus preventive action against their further dispersal and against new invasions is of particular importance.     

The widespread naturalisation of Nymphaea hybrids is masking the decline of wild-type Nymphaea alba in Hesse,Germany

The genus Nymphaea has long been cherished for its ornamental value. Since the end of the 19th century, intensive breeding has produced a large number of widely available hybrids used in horticulture. However, their escape from cultivation and their introduction into the wild pose problems for the conservation of Nymphaea alba in its natural distribution area because many white-flowered hybrids cannot be identified by morphological characters alone. To reliably identify plants of hybrid origin and to study the extent of the invasion of natural habitats by such hybrids, a case study was performed in which plant material was sampled at 34 locations in the federal state of Hesse, Germany, and neighbouring federal states. In addition to morphological information and historical data on the populations, an AFLP analysis was used to distinguish populations of true Nymphaea alba from those of hybrid origin.     

History of plant tissue culture

Plant tissue culture, or the aseptic culture of cells, tissues, organs, and their components under defined physical and chemical conditions in vitro, is an important tool in both basic and applied studies as well as in commercial application. It owes its origin to the ideas of the German scientist, Haberlandt, at the begining of the 20th century. The early studies led to root cultures, embryo cultures, and the first true callus/tissue cultures. The period between the 1940s and the 1960s was marked by the development of new techniques and the improvement of those that were already in use. It was the availability of these techniques that led to the application of tissue culture to five broad areas, namely, cell behavior (including cytology, nutrition, metabolism, morphogenesis, embryogenesis, and pathology), plant modification and improvement, pathogen-free plants and germplasm storage, clonal propagation, and product (mainly secondary metabolite) formation, starting in the mid-1960s. The 1990s saw continued expansion in the application of the in vitro technologies to an increasing number of plant species. Cell cultures have remained an important tool in the study of basic areas of plant biology and biochemistry and have assumed major significance in studies in molecular biology and agricultural biotechnology. The historical development of these in vitro technologies and their applications are the focus of this chapter.     

Identification Keys,the “Natural Method,” and the Development of Plant Identification Manuals

The origins of field guides and other plant identification manuals have been poorly understood until now because little attention has been paid to 18th century botanical identification guides. Identification manuals came to have the format we continue to use today when botanical instructors in post-Revolutionary France combined identification keys (step-wise analyses focusing on distinctions between plants) with the “natural method” (clustering of similar plants, allowing for identification by gestalt) and alphabetical indexes. Botanical works featuring multiple but linked techniques to enable plant identification became very popular in France by the first decade of the 19th century. British botanists, however, continued to use Linnaeus’s sexual system almost exclusively for another two decades. Their reluctance to use other methods or systems of classification can be attributed to a culture suspicious of innovation, anti-French sentiment and the association of all things Linnaean with English national pride, fostered in particular by the President of the Linnean Society of London, Sir James Edward Smith. The British aversion to using multiple plant identification technologies in one text also helps explain why it took so long for English botanists to adopt the natural method, even after several Englishmen had tried to introduce it to their country. Historians of ornithology emphasize that the popularity of ornithological guides in the 19th and 20th centuries stems from their illustrations, illustrations made possible by printing technologies that improved illustration quality and reduced costs. Though illustrations are the most obvious features of late 19th century and 20th century guides, the organizational principles that make them functional as identification devices come from techniques developed in botanical works in the 18th century.     

EMBRYO GROWTH AND SEED SIZE IN RAPHANUS SATIVUS: MATERNAL AND PATERNAL EFFECTS IN VIVO AND IN VITRO

Theories on the evolution of the angiosperm seed disagree as to the effects of different plant tissues on embryo growth. To examine the relative contributions of maternal and paternal genes on embryo growth, we conducted controlled crosses in the greenhouse with wild radish plants (Raphanus sativus), looked for maternal, paternal, and interaction effects on embryo development, and compared the performance of embryos within fruits and in embryo culture. Maternal plant identity affected fruit set, seeds per fruit, embryo developmental stage, and mean seed weight. In embryo culture, maternal effects were found for cotyledon size and embryo weight. Paternal effects were fewer or smaller in magnitude than maternal effects. The identity of the pollen donor affected embryo developmental stage and mean seed weight. In culture, paternal effects were detected for cotyledon size and embryo weight. Our results demonstrate that both maternal and paternal elements affect embryo growth. The fact that maternal effects are greater than paternal effects on embryo development in culture may result from cytoplasmic elements or maternal nuclear genes. Embryo performance in vivo compared to that in vitro varied among maternal plants. The interaction between an embryo and its endosperm and maternal tissues may be either positive or negative, depending upon the maternal plant and the embryo's developmental stage.     

Multicellular behaviour and production of a wide variety of toxic substances support usage of Bacillus subtilis as a powerful biocontrol agent

Intensive cultivation of plants in the monoculture field system in order to feed the continuously growing human population creates a need for their protection from the variety of natural competitors such as: bacteria, fungi, insects as well as other plants. The increase in the use of chemical substances in the 20th century has brought many effective solutions for the agriculture. However, it was extremely difficult to obtain a substance, which would be directed solely against a specific plant pathogen and would not be harmful for the environment. In the late 1900's scientists began trying to use natural antagonisms between resident soil organism to protect plants. This phenomenon was named biocontrol. Biological control of plants by microorganisms is a very promising alternative to an extended use of pesticides, which are often expensive and accumulate in plants or soil, having adverse effects on humans. Nonpathogenic soil bacteria living in association with roots of higher plants enhance their adaptive potential and, moreover, they can be beneficial for their growth. Here, we present the current status of the use of Bacillus subtilis in biocontrol. This prevalent inhabitant of soil is widely recognized as a powerful biocontrol agent. Naturally present in the immediate vicinity of plant roots, B. subtilis is able to maintain stable contact with higher plants and promote their growth. In addition, due to its broad host range, its ability to form endospores and produce different biologically active compounds with a broad spectrum of activity, B. subtilis as well as other Bacilli are potentially useful as biocontrol agents.     

Control of root meristem establishment in conifers

The evolution of terrestrial plant life was made possible by the establishment of a root system, which enabled plants to migrate from aquatic to terrestrial habitats. During evolution, root organization has gradually progressed from a very simple to a highly hierarchical architecture. Roots are initiated during embryogenesis and branch afterward through lateral root formation. Additionally, adventitious roots can be formed post‐embryonically from aerial organs. Induction of adventitious roots (ARs) forms the basis of the vegetative propagation via cuttings in horticulture, agriculture and forestry. This method, together with somatic embryogenesis, is routinely used to clonally multiply conifers. In addition to being utilized as propagation techniques, adventitious rooting and somatic embryogenesis have emerged as versatile models to study cellular and molecular mechanisms of embryo formation and organogenesis of coniferous species. Both formation of the embryonic root and the AR primordia require the establishment of auxin gradients within cells that coordinate the developmental response. These processes also share key elements of the genetic regulatory networks that, e.g. are triggering cell fate. This minireview gives an overview of the molecular control mechanisms associated with root development in conifers, from initiation in the embryo to post‐embryonic formation in cuttings.     

Persistence of a vegetation mosaic in a peripheral region: could turbulent medieval history disrupt Holocene continuity of extremely species-rich grasslands?

Fluctuations in intensity of human impact and corresponding vegetation changes have been reported from different parts of Europe for the period from the beginning of the 1st millennium ad to the high Middle Ages. In the Bílé Karpaty mountains (White Carpathians), a region well-known for its biologically valuable ancient grasslands, an extensive spread of woodland could have occurred in the Migration period (4th–6th century) and especially in the Confinium period (11th–12th century), when settling of this border region was legally prohibited. However, Holocene continuity of non-woodland vegetation was suggested as an explanation for the unique species richness of the local grasslands. If this explanation is true, then the turbulent times in medieval history could not have led to complete re-establishment of woodland. To test this idea palaeoecologically, we analysed four new profiles from wetland deposits for pollen, macrofossils and abiotic proxies, and re-dated some old profiles from the area. The results show the continual presence of human impact indicators since the Migration period in the southwest of the Bílé Karpaty, where these unique grasslands occur. Agricultural activities were indicated by pollen of crops, ruderals, weeds and grassland taxa and by macrofossils of fen-grassland plants. Grazing and burning seem to have been the main disturbances during the older period, while mowing of meadows by scythe became more important since the 17th century. Fossil records differed among the sites as a consequence of differences in altitude and disturbance regimes, but converged gradually with time. Despite intensification of human activities, the landscape remained mosaic-like. Indicators of undisturbed woodlands have been detected only in the northeast. Continuous yet perhaps never too intensive disturbances might therefore have maintained the ancient grassland species pool in the long term.