In this paper, we investigate the Precautionary Principle (PP) in action. Precaution is a fairly new concept in environmental policy. It emerged back in the 1960s but did not consolidate until the 1980s, as it formed part of the major changes taking place in environmental policies at that time. The PP is examined in three contexts. Firstly, we look at the meaning of the concept and how it is disseminated through the media and public discourses to the political arenas of (...) Denmark. Then we examine how the idea is adopted to the political level. Thirdly, we look briefly at the first Danish translation of the principle into a practical context, which includes translations into concrete scientific practices. It is concluded that if the PP shall be more than a simple “idea” or a frequently used “term,” emphasis must be put on the transformation of the concept into concrete practices, like e.g., the alternative testing regimes that we show in the case of plant growth-retarding pesticides presented in this paper. (shrink)

Low birth weight, intrauterine growth retardation, and prematurity are overwhelming risk factors associated with infant mortality and morbidity. The lack of efficacious prenatal screening tests for these three outcomes illuminates the problems inherent in bivariate estimates of association. A biocultural strategy for research is presented, integrating societal and familial levels of analysis with the metabolic, immune, vascular, and neuroendocrine systems of the body. Policy decisions, it is argued, need to be based on this type of biocultural information in order (...) to impact the difficult-to-change problems of low birth weight, intrauterine growth retardation, and prematurity. (shrink)

This article examines to what extent a particular case of cross-disciplinary research in the 1930s was structured by mechanistic reasoning. For this purpose, it identifies the interfield theories that allowed biologists and chemists to use each other’s techniques and findings, and that provided the basis for the experiments performed to identify plant growth hormones and to learn more about their role in the mechanism of plant growth. In 1930, chemists and biologists in Utrecht and Pasadena began (...) to cooperatively study plant growth. I will argue that these researchers decided to join forces because they believed to rely on each other’s findings and methods to solve their research problems adequately. In the course of the cooperation, organic chemists arrived at isolating plant growth hormones by using a test method developed in plant physiology. This achievement, in turn, facilitated biologists’ investigation of the mechanism of plant growth. Researchers eventually believed to have the means to study the relation between a substance’s molecular structure and its physiological activity. The way they conceptualized the problem of identifying hormones and unraveling the mechanism of plant growth, as well as their actual research actions are compatible with the new mechanists’ account of mechanism research. The study illustrates that focusing on researchers’ mechanistic reasoning can contribute considerably to explaining the structure of cross-disciplinary research projects. (shrink)

While several reviews on potential applications of electroculture are available, in this survey we discuss these issues from history, starting from earliest experiments by Ross. And in the last section, we discuss possible application of laserculture, another form of potential improvement. It is our hope that what we present here may be found useful for improving agricultural performance in many countries, as well as reducing dependence on fertilizer.

Arbuscular mycorrhizal fungi are considered as a potential biotechnological tool for improving phytostabilization efficiency and plant tolerance to heavy metal-contaminated soils. However, the mechanisms through which AMF help to alleviate metal toxicity in plants are still poorly understood. A greenhouse experiment was conducted to evaluate the effects of two AMF species on the growth, Pb accumulation, photosynthesis and antioxidant enzyme activities of a leguminous tree at Pb addition levels of 0, 500, 1000 and 2000 mg kg-1 soil. AMF (...) symbiosis decreased Pb concentrations in the leaves and promoted the accumulation of biomass as well as photosynthetic pigment contents. Mycorrhizal plants had higher gas exchange capacity, non-photochemistry efficiency, and photochemistry efficiency compared with non-mycorrhizal plants. The enzymatic activities of superoxide dismutase, ascorbate peroxidases and glutathione peroxidase were enhanced, and hydrogen peroxide and malondialdehyde contents were reduced in mycorrhizal plants. These findings suggested that AMF symbiosis could protect plants by alleviating cellular oxidative damage in response to Pb stress. Furthermore, mycorrhizal dependency on plants increased with increasing Pb stress levels, indicating that AMF inoculation likely played a more important role in plant Pb tolerance in heavily contaminated soils. Overall, both F. mosseae and R. intraradices were able to maintain efficient symbiosis with R. pseudoacacia in Pb polluted soils. AMF symbiosis can improve photosynthesis and reactive oxygen species scavenging capabilities and decrease Pb concentrations in leaves to alleviate Pb toxicity in R. pseudoacacia. Our results suggest that the application of the two AMF species associated with R. pseudoacacia could be a promising strategy for enhancing the phytostabilization efficiency of Pb contaminated soils. (shrink)

A concept for a primitive angiospermous branch system is given in order to have a starting point for the derivation of the diverse and highly differentiated branch systems observed in contemporary angiosperms. Hitherto Troll's (1964, 1969) comparative study of the synflorescences in this plant group — developed out predominantly on herbaceous plants — was the most comprehensive and sophisticated treatment dealing with branch systems. Unfortunately, the work on tropical tree architecture by Hallé et al. (1978) has no reference to (...) the classical studies of Troll and his pupils. Thus Müller-Doblies and Weberling (1984) emphasized the high degree of terminological incompatibility between the two works. Angiosperms are seen as a monophyletic plant division. Consequently, the branch system of the first primitive angiosperms must be the starting point in the evolution of the abundant diversity of branch systems and growth forms of modern angiosperms. If it is accepted that primitive angiospermous shoots were terminated by a large flower, one may assume, that the reproductive end of the shoot was enriched by paracladia early in evolution, thereby developing a terminal inflorescence instead of a single flower. Thus the primitive shoot unit was divided into a basal vegetative region — the trophotagma, branching retardively — and the reproductive terminal region, the anthotagma, branching simultaneously. It is demonstrated through a selection of different examples, that the construction of such a system possesses the options for several modifications, enabling the evolution of the abundant diversity of branch systems which characterizes contemporary angiosperms. (shrink)

Growth mindset is an important aspect of children’s socioemotional development and is subject to change due to environmental influence. Orchestral music education may function as a fertile context in which to promote growth mindset; however, this education is not widely available to children facing economic hardship. This study examined whether participation in a program of orchestral music education was associated with higher levels of overall growth mindset and greater change in levels of musical growth mindset among (...) children placed at risk by poverty. After at least 2 years of orchestral participation, students reported significantly higher levels of overall growth mindset than their peers; participating students also reported statistically significant increases in musical growth mindset regardless of the number of years that they were enrolled in orchestral music education. These findings have implications for future research into specific pedagogical practices that may promote growth mindset in the context of orchestral music education and more generally for future studies of the extra-musical benefits of high-quality music education. (shrink)

The growth activity of an organ (variable y) is defined simultaneously by the instantaneous absolute ratedy/dt and its variationd 2y/dt2. The use of these two descriptors allows a sigmoidal (i.e. continuous and non periodical, as observed for the logistic function) growth curve to be discretized into a series of 5 growth states or phases which are delimited by the following singular values: max, Vmax (=0), max, adult stage. The (V, ) plot, termedgrowth trajectory, visualizes, e.g. in the (...) case of Richards-Nelder's generalized logistics, the unequal duration of these phases and allows the dissymmetry property of the growth function to be characterized precisely.At a more integrated organization level, such anorganic series (e. g. the set of the leaves borne by a same branch), the above concepts allow two kinds of analyses to be carried out: (i) in thekinetic approach, the growth trajectory of the series can characterizes, under certain conditions, the emergence of a new property: theoccurrence of growth activity rhythms which are independent of meristem dormancy processes; (ii) thedemographic approach shows thegrowth structure of the phytomer population (a particular form of age structure) and the associated dimensional structure (plant partition into zones or regions in relation to the growth state of the various phytomers). (shrink)

Volatile compounds, such as nitric oxide and ethylene gas, play a vital role as signaling molecules in organisms. Ethylene is a plant hormone that regulates a wide range of plant growth, development, and responses to stress and is perceived by a family of ethylene receptors that localize in the endoplasmic reticulum. Constitutive Triple Response 1 (CTR1), a Raf‐like protein kinase and a key negative regulator for ethylene responses, tethers to the ethylene receptors, but undergoes nuclear translocation upon (...) activation of ethylene signaling. This ER‐to‐nucleus trafficking transforms CTR1 into a positive regulator for ethylene responses, significantly enhancing stress resilience to drought and salinity. The nuclear trafficking of CTR1 demonstrates that the spatiotemporal control of ethylene signaling is essential for stress adaptation. Understanding the mechanisms governing the spatiotemporal control of ethylene signaling elements is crucial for unraveling the system‐level regulatory mechanisms that collectively fine‐tune ethylene responses to optimize plant growth, development, and stress adaptation. (shrink)

Considering the ways in which plants move and shape the places of their growth, this article suggests that performing arts should account for the vegetal model of movement. The implications of including plants in the category of “moving beings” are vast, as they touch upon the dynamic relation between immanence and transcendence, questions of time-scales appropriate to different kinds of beings and their responses to the environment, and phenomenologies of place corresponding to diverse forms of life. I argue that (...) although, for humans, performing vegetal movement is “performing the unperformable,” art grants us a unique access point to experiencing what is entailed in such movement and in the places wherein it unfolds. (shrink)

Plants from a handful of species provide the primary source of food for all people, yet this source is vulnerable to multiple stressors, such as disease, drought, and nutrient deficiency. With rapid population growth and climate uncertainty, the need to produce crops that can tolerate or resist plant stressors is more crucial than ever. Traditional plant breeding methods may not be sufficient to overcome this challenge, and methods such as highOthroughput sequencing and automated scoring of phenotypes can (...) provide significant new insights. Ontologies are essential tools for accessing and analysing the large quantities of data that come with these newer methods. As part of a larger project to develop ontologies that describe plant phenotypes and stresses, we are developing a plant disease extension of the Infectious Disease Ontology (IDOPlant). The IDOPlant is envisioned as a reference ontology designed to cover any plant infectious disease. In addition to novel terms for infectious diseases, IDOPlant includes terms imported from other ontologies that describe plants, pathogens, and vectors, the geographic location and ecology of diseases and hosts, and molecular functions and interactions of hosts and pathogens. To encompass this range of data, we are suggesting inOhouse ontology development complemented with reuse of terms from orthogonal ontologies developed as part of the Open Biomedical Ontologies (OBO) Foundry. The study of plant diseases provides an example of how an ontological framework can be used to model complex biological phenomena such as plant disease, and how plant infectious diseases differ from, and are similar to, infectious diseases in other organism. (shrink)

Polarity is an inherent feature of almost all prokaryotic and eukaryotic cells. In most eukaryotic cells, growth polarity is due to the assembly of actin‐based growing domains at particular locations on the cell periphery. A contrasting scenario is that growth polarity results from the establishment of non‐growing domains, which are actively maintained at opposite end‐poles of the cell. This latter mode of growth is common in rod‐shaped bacteria and, surprisingly, also in the majority of plant cells, (...) which elongate along the apical–basal axes of plant organs. The available data indicate that the non‐growing end‐pole domains of plant cells are sites of intense endocytosis and recycling. These actin‐enriched end‐poles serve also as signaling platforms, allowing bidirectional exchange of diverse signals along the supracellular domains of longitudinal cell files. It is proposed that these actively remodeled end‐poles of elongating plant cells remotely resemble neuronal synapses. BioEssays 25:569–576, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

The Plant Ontology (PO) (http://www.plantontology.org) (Jaiswal et al., 2005; Avraham et al., 2008) was designed to facilitate cross-database querying and to foster consistent use of plant-specific terminology in annotation. As new data are generated from the ever-expanding list of plant genome projects, the need for a consistent, cross-taxon vocabulary has grown. To meet this need, the PO is being expanded to represent all plants. This is the first ontology designed to encompass anatomical structures as well as (...) class='Hi'>growth and developmental stages across such a broad taxonomic range. While other ontologies such as the Gene Ontology (GO) (The Gene Ontology Consortium, 2010) or Cell Type Ontology (CL) (Bard et al., 2005) cover all living organisms, they are confined to structures at the cellular level and below. The diversity of growth forms and life histories within plants presents a challenge, but also provides unique opportunities to study developmental and evolutionary homology across organisms. (shrink)

In this article, I explore plant semiosis with a focus on plant learning. I distinguish between the scales and levels of learning conceivable in phytosemiosis, and identify organism-scale learning as the distinguishing question for plant semiosis. Since organism-scale learning depends on organism-scale semiosis, I critically review the arguments regarding whole-plant functional cycles. I conclude that they have largely relied on Uexküllian biases that have prevented an adequate interpretation of modern plant neurobiology. Through an examination of (...) trophic growth in plant roots, I expose some conceptual difficulties in attributing functional cycles to whole-plants. I conclude that the mapping of resource areas in the root system is a learning activity requiring higher-scale sign activity than is possible at the cellular scale, strongly suggesting the presence of organism-scale functional cycles. I do, however, question whether all perception-action cycles in organisms are accompanied with organism-scale semiosis. (shrink)

Plants are sessile, highly sensitive organisms that actively compete for environmental resources both above and below the ground. They assess their surroundings, estimate how much energy they need for particular goals, and then realise the optimum variant. They take measures to control certain environmental resources. They perceive themselves and can distinguish between ‘self’ and ‘non-self’. They process and evaluate information and then modify their behaviour accordingly. These highly diverse competences are made possible by parallel sign(alling)-mediated communication processes within the (...) class='Hi'>plant body (intraorganismic), between the same, related and different species (interorganismic), and between plants and non-plant organisms (transorganismic). Intraorganismic communication involves sign-mediated interactions within cells (intracellular) and between cells (intercellular). This is crucial in coordinating growth and development, shape and dynamics. Such communication must function both on the local level and between widely separated plant parts. This allows plants to coordinate appropriate response behaviours in a differentiated manner, depending on their current developmental status and physiological influences. Lastly, this volume documents how plant ecosphere inhabitants communicate with each other to coordinate their behavioural patterns, as well as the role of viruses in these highly dynamic interactional networks. (shrink)

Like several other classes of hormones, the class of plant hormones called auxins exert myriad effects on cell development. While auxins are most noted for inducing cell elongation, they are also involved in cell division, cell differentiation, cell and organ polarity, and wound responsiveness. Consistent with this pleiotropy, is the recent identification of several putative auxin receptors that in theory could represent the primary elements of more than one auxin signal pathway leading to distinct responses or leading in parallel (...) to a single response. Our current working hypothesis is that some auxin‐mediated responses may be mediated by multiple receptors. We describe some of what is known about each of the new putative receptors and elaborate on the hypothesis using the example of cell elongation. Specifically for auxin‐induced elongation, we propose that two rapid events, specific gene transcription and cell wall acidification, are separately mediated by at least two receptors, acting in the nucleus and at the plasma membrane, respectively. (shrink)

The physiology of plant hormones was one of the most dynamic fields in experimental biology in the 1930s, and an important part of T. H. Morgan's influential life science division at the California Institute of Technology. I describe one episode of plant physiology research at the institution in which faculty member James Bonner discovered that the B vitamin thiamin is a plant growth regulator, and then worked in close collaboration with the Merck pharmaceutical firm to develop (...) it as a growth-boosting agrichemical. This episode allows one to draw continuities between certain fields of life science in the United States circa 1940 and the biotechnology industry today, and also foregrounds a number of similarities between plant physiology of the late 1930s and the molecular biology of the period. (shrink)

Plant hormones are signalling molecules that control growth and development. Growth of the aerial parts of higher plants requires the continuous activity of the shoot apical meristem, a small mound of cells at the apex of a plant. KNOTTED1‐like HOMEOBOX (KNOX) genes are involved in regulating meristem activity, however, little is known about how this regulation is mediated. Recent evidence suggests that KNOX transcription factors may control meristem development by regulating the balance of activities of multiple (...) hormones. BioEssays 26:395–404, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

This is an article in Thomas J.J. McCloughlin (Ed.) The Nature of Science in Biology: A Resource for Educators. Graphikon Teo, Dublin. -/- Abstract: Philosophers usually tend to think of animals when they think about life, plants often only appear in their works as on the margins, in the background; they are rarely in the centre. However, plant life involves unique processes, including remarkable modes of interaction between plants and their environments. Needless to say, plants are vital parts of (...) ecosystems. Serious attention to plants provides novel and interesting perspectives on many topics in philosophy of biology, including individuality, organisation and disease. Plant biology should have a substantial part in philosophy education. To support this assertion, this paper briefly describes three topics related to plant-environment interaction and explains some of their philosophical implications. These topics are growth, plant hormones and plant-plant microbiota interactions, all of which present crucial aspects related to some prevalent topics in philosophy of biology such as individuality, systems thinking, and holobiont. (shrink)

In the article, the social structure of mountain-plant serf population of fief and seasonal plants in the Southern Urals in the first half of the 19th century is studied. It is noted that due to the kind of their activity, all mountain-plant population was in this or that way connected with plant work; according to their social structure they were peasants, bought for the plants, or were the owners’ private serfs. It is shown that because of the (...) variety of industrial work at a plant, the serfs of the plant-owners were categorized and differed according to the working conditions and possibilities of their own management. The Southern Urals is noted to have become the arena of private mining industry activity as compared to other areas of the country. The fact predetermining the social composition of factory population. The sources of formation and growth of the group of factory peasants of the Southern Urals are shown. In the article, the social structure is analyzed and social groups of factory peasants are described for three different mining areas of the region. (shrink)

This paper reports on the long-term effectiveness of a non-formal co-curricular educational program based on a campus ecogarden at a Hong Kong university in developing pro-sustainability awareness, attitudes and behavior among undergraduate students. This service-based, nature-based experiential learning program, termed the Ecogarden Farmer and Biodiversity Surveyor, has been running at the university since 2015. The program is divided into two consecutive phases: a training phase comprising various learning activities and a successive internship phase consisting of the all-round practical tasks involved (...) in managing the garden. A retrospective evaluation of the program using phenomenographic approach and content analysis was adopted to reveal the diversity of students’ learning experience, as the indicators of the success of the program. Of 112 participants from 4 cohorts, 32 completed online questionnaires, and semi-structured interviews were successfully conducted with twelve participants, three from each of the four cohorts. The results indicated that the program’s outcomes could be categorized into five themes. Most outcomes fit into the theme ‘an increase in knowledge and skill level,’ followed by ‘rise in environmental awareness,’‘facilitation of personal growth,’ and ‘enhancement of career development.’ Many structural experiences revealed may suggest the success of the program. The longer the participants had participated in the program, the more in-depth and diversified reflection of the senior participants relating to personal development were mentioned. This study provides critical insights into the validity of retrospective program evaluation for assessing the long-term impact of EfS programs by introducing a cross-sectional study of different cohorts as a serial time-point sampling strategy. (shrink)

Several conceptual and methodological challenges must be solved in order to create knowledge that can be useful to pregnant women, their families, and any clinicians who serve them: (1) going beyond nominal and ordinal hypotheses and presenting estimates of conditional probabilities; (2) focusing on clearly defined outcomes; (3) modeling the relationship of fetal growth and length of gestation; (4) understanding the process of fetal growth even though most of our data is cross-sectional; (5) estimating the independent effects of (...) genetics, race, ethnicity, maternal risk behaviors, medical prenatal care, and socioeconomic status on fetal growth and length of gestation; and (6) estimating the independent effects of maternal pre-pregnancy weight, weight gain during pregnancy, and nutrition on fetal growth and length of gestation. (shrink)

A geometrical model is proposed that describes the emergence of a primordium at the shoot apex in Dicotyledons. It is based on recent fundamental results on plant morphogenesis, viz.: – the emergence is preceded by the reorganization of the microtubules of the cortical cytoskeleton, leading to a new orientation of the synthesis of the cell wall microfibrils; – the resulting global stress is related to the general orientation of the cell growth.

The paper deals with an intellectual and historical approach to the changing meanings of the term “model” in life sciences. The author 1st tries to understand how modeling has gradually spread over life sciences then he particularly focus on the birth of mathematical modeling in this field. This quite new practice offers new insights on the old debate concerning the mathematization of life sciences. Nowadays, through computers, mathematics not only analyze or quantify but model things: what does it mean? The (...) question turns out to be dramatic as far as digital simulation is concerned. That is the reason why he choosed to study a particular case: the history of the individual plant mathematical modeling. On this case, one may discern various epistemological standpoints that caused various reactions to the emergence of computer simulation, from the 50s to the 90s. The author shows that philosophical views often play a role in the history of sciences, especially in the choice of supposed proper mathematical formalisms. This will indicate that contemporary discourses tend to echo each other. That is the reason why he feels authorized to address the Foucault’s concept—épistémè—to denote these convergences between the scientific and the philosophical discourses. Finally, it is suggested that this épistémè gradually is changing because one can currently observe the emergence of a “graphical” thought through these simulation experiments, which tends to replace a more functionalist thought. (shrink)

To cope with the water deficit resulting from saline environment, plant cells accumulate three kinds of osmotica: salts, small organic solutes and hydrophillic, glycine-rich proteins. Salts such as NaCl are cheap and available but has ion toxicity in high concentrations. Small organic solutes are assistant osmotica, their main function is to protect cytoplasmic enzymes from ionic toxicity and maintain the integrity of cellular membranes. Hydrophillic, glycine-rich proteins are the most effective osmotica, they have some characteristics to avoid crystallization even (...) in high concentration, but because they are expensive they are not as commonly used as salts or organic solutes. In addition there is the question of whether the genetic information for growth in saline environment is present in all kinds of plants, both halophytes and nonhalophytes. (shrink)

Despite their conceptual allergy to vegetal life, philosophers have used germination, growth, blossoming, fruition, reproduction, and decay as illustrations of abstract concepts; mentioned plants in passing as the natural backdrops for dialogues, letters, and other compositions; spun elaborate allegories out of flowers, trees, and even grass; and recommended appropriate medicinal, dietary, and aesthetic approaches to select species of plants. In this book, Michael Marder illuminates the vegetal centerpieces and hidden kernels that have powered theoretical discourse for centuries. Choosing twelve (...) botanical specimens that correspond to twelve significant philosophers, he recasts the development of philosophy through the evolution of human and plant relations. A philosophical history for the postmetaphysical age, The Philosopher's Plant reclaims the organic heritage of human thought. With the help of vegetal images, examples, and metaphors, the book clears a path through philosophy's tangled roots and dense undergrowth, opening up the discipline to all readers. (shrink)

The exploration of plant behavior on a cellular scale in a minimal invasive manner is key to understanding plant adaptations to their environment. Plant hormones regulate multiple aspects of growth and development and mediate environmental responses to ensure a successful life cycle. To monitor the dynamics of plant hormone actions in intact tissue, we need qualitative and quantitative tools with high temporal and spatial resolution. Here, we describe a set of biological instruments (reporters) for the (...) analysis of the distribution and signaling of various plant hormones. Furthermore, we provide examples of their utility for gaining novel insights into plant hormone action with a deeper focus on the drought hormone abscisic acid. (shrink)

A lot of scholarly attention has been given to Aristotle’s account of how and why animals are capable of moving themselves. But no one has focused on the question, whether self-change is possible in plants on Aristotle’s account. I first give some context and explain why this topic is worth exploring. I then turn to Aristotle’s conditions for self-change given in Physics VIII.4, where he argues that the natural motion of the elements does not count as self-motion. I apply those (...) conditions to natural change in plants. Then I explore the reasons for and consequences of Aristotle’s argument that plants are incapable of sensation. I argue that for Aristotle plants cannot possess the directing faculties for self-change, namely, desire and phantasia. My goal is to show why growth, metabolism, and reproduction in plants would not count as self-change for Aristotle, despite many of these natural changes appearing as autonomous as the analogous changes in animals. This sheds light on how, for Aristotle, self-change differs from natural change. (shrink)

Reactive oxygen species (ROS) are known as toxic metabolic products in plants and other aerobic organisms. An elaborate and highly redundant plant ROS network, composed of antioxidant enzymes, antioxidants and ROS-producing enzymes, is responsible for maintaining ROS levels under tight control. This allows ROS to serve as signaling molecules that coordinate an astonishing range of diverse plant processes. The specificity of the biological response to ROS depends on the chemical identity of ROS, intensity of the signal, sites of (...) production, plant developmental stage, previous stresses encountered and interactions with other signaling molecules such as nitric oxide, lipid messengers and plant hormones. Although many components of the ROS signaling network have recently been identified, the challenge remains to understand how ROS-derived signals are integrated to eventually regulate such biological processes as plant growth, development, stress adaptation and programmed cell death. (shrink)

Growth of spring barley stands was followed in various conditions. Disposition of the seeds parameters the morphogenetic programme of each individual plant, which will afterwards form the stricture of the young plant stand. Later, individual stopping of tillering is controlled by this stricture. In return, the distribution of these events conditions the structure of the canopy during the shoot lengthening period. In sparse or patchy canopies, weak tillers in stopping of growth are able to survive temporarily.The (...) plant is not reducible to the genotype of its variety. Individual whole plant and plant stand are true organization levels in an ecosystem. It is essential to take their relationships into account throughout the growth for understanding the behaviour of a crop. (shrink)

This contribution demonstrates that the development and growth of plants depends on the success of complex communication processes. These communication processes are primarily sign-mediated interactions and are not simply an mechanical exchange of ‘information’, as that term has come to be understood (or misunderstood) in science. Rather, such interactions as I will be describing here involve the active coordination and organisation of a great variety of different behavioural patterns — all of which must be mediated by signs. Thus proposed, (...) a biosemiotics of plant communication investigates communicationprocesses both within and among the cells, tissues, and organs of plants as sign-mediated interactions which follow (1) combinatorial (syntactic), (2) context-sensitive (pragmatic) and (3) content-specific (semantic) levels of rules. As will be seen in the cases under investigation, the context of interactionsin which a plant organism is interwoven determines the content arrangement of its response behaviour. And as exemplified by the multiply semiotic roles playedby the plant hormone auxin that I will discuss below, this means that a molecule type of identical chemical structure may function in the instantiation of differentmeanings (semantics) that are determined by the different contexts (pragmatics) in which this sign is used. (shrink)

Human chromosome 11p15 comprises two imprinted domains important in the control of fetal and postnatal growth. Novel studies1-3 establish that imprinting at one of these, the IGF2-H19 domain, is epigenetically deregulated (with loss of DNA methylation) in Silver-Russell Syndrome (SRS), a congenital disease of growth retardation and asymmetry. Previously, the exact opposite epigenetic alteration (gain of DNA methylation) had been detected at the domain's ‘imprinting control region’ (ICR) in patients with Beckwith-Wiedemann Syndrome (BWS), a complex disorder of fetal (...) overgrowth. However, more frequently, BWS is caused by loss of DNA methylation at the ICR that regulates the second imprinted domain at 11p15. Interestingly, a similar epigenetic alteration (with loss of methylation) at a putative ICR on human chromosome 6q24, is involved in transient neonatal diabetes mellitus (TNDM), a congenital disease with intrauterine growth retardation and a transient lack of insulin. Thus, fetal and postnatal growth is epigenetically controlled by different ICRs, at 11p15 and other chromosomal regions. BioEssays 28: 453–459, 2006. © 2006 Wiley Periodicals, Inc. (shrink)

Insect and pathogen attacks activate plant defense genes within minutes in nearby cells, and within hours in leaves far distant from the sites of the predator attacks. A search for signal molecules involved in both the localized and distal signalling has resulted in the identification of an 18‐amino‐acid polypeptide, called systemin, that activates defense genes in leaves of tomato plants when supplied at levels as low as fmols/plant. Several lines of evidence support a role for systemin as a (...) wound hormone. As with animal polypeptide hormones, systemin is derived from a larger precursor protein, called prosystemin, by limited proteolysis. Systemin has been shown by autoradiography to be phloemmobile and, by antisense technology, to be an essential component of the wound‐inducible, systemic signal transduction system leading to the transcriptional activation of the defensive genes. A search for the receptor of systemin has led to the identification in plant plasma membranes of a systeminbinding protein. However, this protein has properties not of a receptor, but of a furin‐like proteinase that cleaves systemin into smaller polypeptides. Systemin and its precursor prosystemin provide prototypes for the emerging possibilities that polypeptide hormones may have broad roles in signalling environmental stress responses, and in regulating plant growth and development as well. (shrink)

Some biologists now argue in favour of a pluralistic approach to plant activities, understandable both from the classical perspective of physiological mechanisms and that of the biology of behaviour involving choices and decisions in relation to the environment. However, some do not hesitate to go further, such as plant “neurobiologists” or philosophers who today defend an intelligence, a mind or even a plant consciousness in a renewed perspective of these terms. To what extent can we then adhere (...) to pluralism in the study of plant behaviour? How does this pluralism in the study and explanation of plant behaviour fit into, or even build itself up, in a broader history of science? Is it a revolutionary way of rethinking plant behaviour in the twenty-first century or is it an epistemological extension of an older attitude? By proposing a synthesis of the question of plant behaviour by selected elements of the history of botany, the objective is to show that the current plant biology is not unified on the question of behaviour, but that its different tendencies are in fact part of a long botanical tradition with contrasting postures. Two axes that are in fact historically linked will serve as a common thread. 1. Are there several ways of understanding or conceiving plant behaviour within plant sciences and their epistemology? 2. Can the behaviour of a plant be considered in the same way as that of an animal? The working hypothesis defended in this article consists in showing that the current opposition between growth, development and reductionist physiology on the one hand and the biology of behaviour involving sensitivity and choices in plant activity on the other hand has been built up through the history of botany. (shrink)

Plant protection problems are simulated by a system of ordinary differential equations with given initial conditions. The sensitivity and resistance of pathogen subpopulations to fungicide mixtures, fungicide weathering, plant growth, etc. are taken into consideration. The system of equations is solved numerically for each set of initial conditions and parameters of the disease and fungicide applications. Optimization algorithms were investigated and a computer program was developed for optimization of these solutions. 14 typical cases of the disease were (...) simulated and optimized in order to determine optimal fungicide treatments. The optimized strategy for fungicide application differs considerably from the commonly used method and seems to be an important new principle in plant protection. The approach developed in this study may be useful for a wide spectrum of purposes in the simulation of leaf diseases. It may also help the biologist to decrease or pinpoint experimental work and analyze its results and is perspective for plant disease control. (shrink)

From the point of view of a dynamic morphology, form is not only the result of process(es) — it is process. This process may be analyzed in terms of two pairs of fundamental processes: growth and decay, differentiation and dedifferentiation. Each of these processes can be analyzed in terms of various modalities (parameters) and submodalities. This paper deals with those of growth (see Table 1). For the purpose of systematits and phylogenetic reconstruction the modalities and submodalities can be (...) considered dynamic characters that have states. Each state of such a dynamic character is a more detailed process, hence not static. For example, determinate growth represents a state of the dynamic character (or modality) of growth duration.The processes of Table 1 can be applied to the whole plant kingdom (although in certain cases only some processes of the whole set may be applicable). Thus, the diversity of plant form is seen as a diversity of process combinations. From this point of view, change in form implies change in the process combination(s). Questions that arise are, for example, the following: Which process combinations actually occur? Which of these are the most frequent? How and why have process combinations changed during ontogeny and phylogeny? (shrink)

In addition to their function in transport of water, ions, small metabolites, and growth factors in normal plant tissue, the plasmodesmata presumably serve as routes for cell‐to‐cell movement of plant viruses in infected tissue. Virus cell‐to‐cell spread through plasmodesmata is an active process mediated by specialized virus encoded movement proteins; however, the mechanism by which these proteins operate is not clear. We incorporate recent information on the biochemical properties of plant virus movement proteins and their interaction (...) with plasmodesmata in a model for transport of nucleic acids through plasmodesmatal channels. We propose that only single stranded (ss) nucleic acids can be transported efficiently through plasmodesmata, and that movement proteins function as molecular chaperones for ss nucleic acids to form unfolded movement protein‐ss nucleic acid complexes. These complexes are targeted to plasmodesmata. Plasmodesmatal permeability is then increased following interaction with movement protein and the entire movement complex or its nucleic acid component is translocated across the plasmodesmatal channel. (shrink)

Three approaches have been used to investigate the inhibitory role of the cytokinin class of phytohormones in plant senescence: external application of cytokinins, measurement of endogenous cytokinin levels before and during senescence, and manipulation of endogenous cytokinin production in transgenic plants. In transgenic plant studies, endogenous cytokinin levels are manipulated by expression of IPT, a gene encoding isopentenyl transferase. Transgenic plants expressing IPT from a variety of promoters exhibit developmental and morphological alterations and often display retarded leaf senescence. (...) A recently developed autoregulatory senescence‐inhibition system targets cytokinin production quantitatively, spatially and temporally, and results in transgenic plants that exhibit significantly delayed senescence without abnormalities. These transgenic studies not only confirm the regulatory role of cytokinins in plant senescence, but also provide a way to manipulate senescence for potential agricultural applications. (shrink)

Despite the enormous diversity in plant form, structure and growth environment across the seed‐bearing plants (angiosperms and gymnosperms), the chloroplast genome has, with few exceptions, remained remarkably conserved. This conservation suggests the existence of universal evolutionary selection pressures associated with photosynthesis—the primary function of chloroplasts. The stark exceptions to this conservation occur in parasitic angiosperms, which have escaped the dominant model by evolving the capacity to obtain some or all of their carbon (and nutrients) from their plant (...) hosts. The consequence of this evolution to parasitism is a relaxation of the evolutionary constraints associated with the need to maintain photosynthetic function, the very function that drove early stages of the ancient symbiotic relationship that produced the contemporary chloroplast. Extreme examples of reductionism among parasitic angiosperms reveals major alterations in chloroplast function with the loss of photosynthetic capacity and, with that, massive alterations in chloroplast genome content. This review highlights emerging patterns in reported gene loss and gene retention in the chloroplast genomes of parasitic plants. Some gene losses appear to occur in the early stages of parasitic evolution, even before the loss of photosynthetic capacity, like the chlororespiratory (ndh) genes. This contrasts with unexpected gene retentions, like that of the rbcL gene responsible for photosynthetic carbon dioxide fixation, and belies current understanding of gene function. The review relates gene retention to current knowledge of protein function and gene processing that has implications to broader aspects of genome conservation in organelles. BioEssays 26:235–247, 2004. Wiley Periodicals, Inc. (shrink)

Steroid hormones are signaling molecules important for normal growth, development and differentiation of multicellular organisms. Brassinosteroids (BRs) are a class of polyhydroxylated steroids that are necessary for plant development. Molecular genetic studies in Arabidopsis thaliana have led to the cloning and characterization of the BR receptor, BRI1, which is a transmembrane receptor serine/threonine kinase. The extracellular domain of BRI1, which is composed mainly of leucine‐rich repeats, can confer BR responsivity to heterologous cells and is required for BR binding. (...) Although downstream components of BR action are mostly unknown, multiple genes whose expression are regulated by BRs have been identified and suggest mechanisms by which BRs affect cell elongation and division. BioEssays 23:1028–1036, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

Public parks play important roles in conserving biodiversity, promoting environmental sustainability, fostering community engagement, and enhancing the overall well-being of residents in urban areas. Nevertheless, finance is needed to maintain and expand the greenspaces in the parks. The current study aims to examine how perceptions of biodiversity loss consequences and park visitation frequency influence the residents’ willingness to contribute financially to tree-planting projects in public parks. Employing the Bayesian Mindsponge Framework analytics on a dataset of 535 Vietnamese urban residents, we (...) discovered that perceived health loss and knowledge erosion as consequences of biodiversity loss and park visitation frequency are directly positively associated with financial donation willingness. Meanwhile, the perceived economic growth loss was found to be indirectly positively associated with donation willingness through park visitation frequency, whereas the perceived loss of nature-based recreation opportunities exhibits the opposite indirect association. Based on these results, communication strategies focusing on the multifaceted benefits of biodiversity preservation and investments in public parks are recommended to improve urban residents’ financial support to park panting initiatives, accessibility to greenspaces, and connections with nature. These are crucial for promoting an eco-surplus culture that enhances biodiversity conservation and human well-being. (shrink)

Two main attempts have been suggested for the biological significance of endopolyploidy: (i) provision of high DNA amounts to support high synthetic demands in certain cells and (ii) compensation for a lack of nuclear DNA in species with small genomes. However, in seed plants, the positive correlation between DNA content and cell volume of endopolyploid cells suggests other possibilities. Cell size paralleled by the endopolyploidy level has an impact on growth and development. Endopolyploidy levels in turn are characteristic for (...) a given species and even families, reflecting the adaptation to certain habitats during phylogeny. Furthermore, endopolyploidy levels vary to some degree between individuals of one species in response to different environmental conditions. In addition, endopolyploidy differs between different tissues suggests that a certain cell size is advantageous for a given cell function. This article reviews these findings and discusses more conclusive possible functions of endopolyploidy. BioEssays 28: 271–281, 2006. © 2006 Wiley Periodicals, Inc. (shrink)

The journal continues to publish translations of individual chapters of the book by the famous phenomenologist Michael Marder "Plants of Philosophers (Intellectual Herbarium)". Out of twelve stories, "Irigaray’s Water Lily" was chosen. The author analyzes the views of a modern French philosopher Luce Irigaray, whose numerous books contain a feminist revision of traditional philosophy and its language. Today, having thrown off the straitjacket of metaphysical reasoning, living thought turns to physicality, marked by finiteness and sexual differences, as well as to (...) the surrounding world, to the rhythms of the earth and the richness of non-Western philosophical traditions. Luce Irigaray's creativity is rooted in all those dimensions of experience that she was able to restore at the sunset of metaphysics. In the work of Irigaray, the vegetable occupies a special place and stimulates the development of her thoughts. Plants provide her with a model of thinking, living and cultivating subjectivity. Cultivation in this case does not mean the formation of the physis in accordance with the predetermined parameters of the mind or the forcible eradication of what grows by itself. On the contrary, cultivating nature, for example, means that we put ourselves at her service, protecting, participating and encouraging myriad plants. Irigaray calls us to listen to the muted vegetative rhythms of our life and thinking, whose growth has been stopped by the prejudices of metaphysics and the arrhythmia of modern existence. Everything that Western philosophers from Aristotle to Hegel rejected and devalued in relation to plants, in her works is lovingly extracted, overestimated and cultivated. (shrink)

Arabidopsis thaliana is a small cruciferous weed which grows naturally, mainly in Europe. Because of its qualities of small size, rapid growth, low chromosome number and self‐fertilisation, I adapted it to aseptic growth in purified agar in sterile test‐tubes. I found that it secreted various substances into the medium, but not in type or amount likely to interfere with the expression of biosynthetic mutants. Following X‐irradiation of seed, I obtained a number of mutants, including several lethals. One lethal (...) mutant I discovered to be deficient in thiamine synthesis. It was the first biosynthetic mutant to be found in flowering plants. (shrink)

In "The Metamorphosis of Plants" (1790) and the related didactic poem (1798) Goethe describes the generation and development of plants as six metamorphoses of the primal plant and its organ, the leaf. In a first step, I will try to analyze the nature of the primal plant and its organ, the leaf. Is the primal plant and its organ, the leaf, an idea or does it consist in matter? If it is an idea, is it the idea (...) of all plants (the plant), the idea of a particular species of plants, or the idea of the individual plant? If it is matter – which kind of matter? In a second step, I will analyze the generic nature of the primal plant and its organ, the leaf. How does the metamorphosis of plants proceed? Suppose the leaf is A and the parts of the plants are B, C and D. Does A transform into B, C, D by a process from A to B to A, from A to C to A, and from A to D to A; or does A transform into B, proceed from B as B to C, and proceed from C as C to D; or does A transform into B, while remaining at the same time A, and proceed from B as A to C, while remaining at the same time A, and proceed from C as A to D, while remaining at the same time A? Which of these models explains our experience of plant generation and growth and allows a meaningful interpretation of Goethe's mysterious claim that 'All is leaf'? (shrink)

Each plant can be recognized by its general shape. Nevertheless, this physiognomy is the result of a very precise structure that expresses the existence of a strong organization. The architecture of a plant depends on the nature and relative arrangement of each of its parts; it is at any given time the result of an equilibrium between endogenous growth processes and the constraints exerted by the environment. Architectural studies have been carried out for some twenty years and (...) have led to the definition of several concepts that provide a powerful tool for studying plant form. The results obtained in this field show that the architecture of a plant can be summarized by a small number of elementary structures: internode, growth unit, axis, architectural model,... In the course of ontogenesis, these structures are repeated and reveal several levels of organization that seem to be only different stages of a common process of growth and transformation. (shrink)