SEARCH · Search PubMed
Results for “Botany”
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Science in New York City, 1867-1907.
Explore the source record for details and available documents.
Juxtaposed medical traditions: Pliny HN 27, 131.
Explore the source record for details and available documents.
Knowledge held in common. Tales of Luther Burbank and science in the American vernacular.
During the first half of the twentieth century, the horticulturist Luther Burbank was largely considered an irrelevant figure by the scientific community, despite winning acclaim from the public as an eminent scientist. In examining the intellectual, social, and political claims embedded in texts by and about Burbank, this essay argues that consideration of the Burbank stories as they circulated in the vernacular realm can aid historians in understanding the dynamics of science in American life. Among the themes it addresses are how the Burbank stories directly engaged the question of who should legitimately count as a student of nature; the varied philosophical perspectives that derived from siting science within the deomestic sphere; and how these stories played with the possibility of a philosophy of nature based on the concept of "living matter," as opposed to one grounded on mechanistic principles. The essay also discusses how Burbank's views on evolution were mediated by the image of the child and the way in which his convictions regarding the power of the environment to release latent characteristics in physiological material presented a view of the future of the American "race" that was at odds with conventional eugenic thinking and assigned a central role to women in the drama of American evolution.
Exploring the city of Rubble: botanical fieldwork in bombed cities in Germany after World War II.
In recent decades, the flora and fuana of cities have become the objects of the inter-disciplinary research field of urban ecology and related policies of urban nature conservation. Although the term "urban ecology" is quite recent, it is argued in this paper that the formation of urban nature as an object of ecological knowledge has a much longer history. For example, in Germany, after World War II, the large rubble areas that existed in all bombed cities soon became important research fields for botanists studying plant migration and vegetation development in the context of the city. This paper uses the case of these botanical research activities to shed light on the historical origins of ecological thinking about nature in the city. Drawing upon a socio-spatial approach to science and practice, the paper explores the interaction between the social and material order of the city and the formation of ecological knowledge. As will be shown, botanists studying the rubble areas created various representations (e.g., lists, statistical tabulations, maps) of urban space that contributed to the transformation of the cultural and political meaning of urban wastelands. At the same time, it will be argued, urban wastelands were practically appropriated as scientific workplaces in which these representations were locally crafted. What later became the science and politics of urban ecology is to a large extent the outcome of this mutual shaping of knowledge and urban space in the post-Second World War period.
Goethean science: an alternative approach.
This paper considers the science of the poet Goethe as furnishing a complementary epistemology for complementary and alternative medicine (CAM), standing alongside and very different from conventional scientific methodology. Through reference to key texts it explores the phenomenological "science of qualities" that aims to allow the scientist, through robust training, to appreciate and intuit the wholeness inherent in nature, so that Goethe could claim the human being to be the most sensitive instrument. Goethe's color theory-a challenge to Newtonian thinking-and his study of plants are explored to illustrate a profoundly different way of looking at nature that celebrates the subjective and relational as a route to perceiving the whole. Ideas toward application of Goethe's approach within CAM are considered and the relevance of this approach as an alternative methodological enquiry toward consideration of wholeness and healing are offered.
Regulation of potassium transport in leaves: from molecular to tissue level.
Over millions of years, plants have evolved a sophisticated network of K+ transport systems. This Botanical Briefing provides an overview of K+ transporters in various leaf tissues (epidermis, mesophyll, guard cells and vascular system) at both the cellular and organelle levels. Despite the tremendous progress in our knowledge of genes encoding K+ transport systems in plants, understanding has not developed of coordinated functioning and operation of these genes or proteins in the context of whole plant physiology and plant-environment interaction. This Botanical Briefing is aimed at filling that gap by analysing electrophysiological and molecular evidence for mechanisms coordinating K+ transport between various leaf cells and tissues in changing environments.
Structure and function of plant canopies.
This section comprises a set of papers taken from those presented at a symposium held to commemorate the 50th anniversary of the Monsi-Saeki theory (1953), together with invited papers. The papers describe recent advances in the study of structure and function of plant canopies and are written by former students (and their collaborators) of Professors Monsi and Saeki. The topics cover construction and maintenance of efficient photosynthetic systems at leaf, individual plant and stand level. Canopy structure and function are analysed with respect to optimization and an evolutionarily stable strategy. A new translation of the original paper by Monsi and Saeki (1953) into English has been commissioned and is included in this section.
Development of the Monsi-Saeki theory on canopy structure and function.
BACKGROUND AND AIMS: Monsi and Saeki (1953) published the first mathematical model of canopy photosynthesis that was based on the light attenuation within a canopy and a light response of leaf photosynthesis. This paper reviews the evolution and development of their theory. SCOPE: Monsi and Saeki showed that under full light conditions, canopy photosynthesis is maximized at a high leaf area index (LAI, total leaf area per unit ground area) with vertically inclined leaves, while under low light conditions, it is at a low LAI with horizontal leaves. They suggested that actual plants develop a stand structure to maximize canopy photosynthesis. Combination of the Monsi-Saeki model with the cost-benefit hypothesis in resource use led to a new canopy photosynthesis model, where leaf nitrogen distribution and associated photosynthetic capacity were taken into account. The gradient of leaf nitrogen in a canopy was shown to be a direct response to the gradient of light. This response enables plants to use light and nitrogen efficiently, two resources whose supply is limited in the natural environment. CONCLUSION: The canopy photosynthesis model stimulated studies to scale-up from chloroplast biochemistry to canopy carbon gain and to analyse the resource-use strategy of species and individuals growing at different light and nitrogen availabilities. Canopy photosynthesis models are useful to analyse the size structure of populations in plant communities and to predict the structure and function of future terrestrial ecosystems.
Phenology of flowering and starch accumulation in grape (Vitis vinifera L.) cuttings and vines.
BACKGROUND AND AIMS: A reliable protocol for flowering and fruiting in cuttings was developed with the aim of (a) studying inflorescence and flower development in grapevine cuttings and field plants, and (b) assisting haploid plant production. METHODS: Inflorescence and flower development was studied in 'Gewurztraminer' (GW) and 'Pinot Noir' (PN) grape vines and cuttings grown in a glasshouse, along with variations in starch in the flowers. As there is a strong relationship between flower development and starch, the starch content of reproductive structures was estimated. KEY RESULTS: Inflorescence and flower development were similar in the vines and cuttings with consistent differences between the two cultivars. Indeed, the ontogenesis of male and female organs is not synchronous in GW and PN, with both female and male meiosis occurring earlier in PN than in GW. Moreover, changes of starch reserves were similar in the two plant types. CONCLUSIONS: Cuttings have a similar reproductive physiology to vines, and can be used to study grape physiology and to develop haploid plants.
The cucurbit images (1515-1518) of the Villa Farnesina, Rome.
BACKGROUND: The gorgeous frescoes organized by the master Renaissance painter Raphael Sanzio (1483-1520) and illustrating the heavenly adventures of Cupid and Psyche were painted between 1515 and 1518 to decorate the Roman villa (now known as the Villa Farnesina) of the wealthy Sienese banker Agostino Chigi (1466-1520). Surrounding these paintings are festoons of fruits, vegetables and flowers painted by Giovanni Martini da Udine (1487-1564), which include over 170 species of plants. A deconstruction and collation of the cucurbit images in the festoons makes it possible to evaluate the genetic diversity of cucurbits in Renaissance Italy 500 years ago. FINDINGS: The festoons contain six species of Old World cucurbits, Citrullus lanatus (watermelon), Cucumis melo (melon), Cucumis sativus (cucumber), Ecballium elaterium (squirting cucumber), Lagenaria siceraria (bottle gourd) and Momordica balsamina (balsam apple), and two or three species of New World cucurbits, Cucurbita maxima, C. pepo and, perhaps, C. moschata (pumpkin, squash, gourd). The images of C. maxima are the first illustrations of this species in Europe.
First known image of Cucurbita in Europe, 1503-1508.
BACKGROUND: The genus Cucurbita (pumpkin, squash, gourd) is native to the Americas and diffused to other continents subsequent to the European contact in 1492. For many years, the earliest images of this genus in Europe that were known to cucurbit specialists were the two illustrations of C. pepo pumpkins that were published in Fuchs' De Historia Stirpium, 1542. Images of fruits of two Cucurbita species, drawn between 1515 and 1518, were recently discovered in the Villa Farnesina in Rome. FINDINGS: An even earlier image of Cucurbita exists in the prayer book, Grandes Heures d'Anne de Bretagne, illustrated by Jean Bourdichon in Touraine, France, between 1503 and 1508. This image, which shows a living branch bearing flowers and fruits, had not been examined and analysed by cucurbit specialists until now. The image is identified as depicting Cucurbita pepo subsp. texana. Unlike some of the fruits of Cucurbita depicted in the Villa Farnesina a decade later, this image does not depict an esculent and does not constitute evidence of early European contact with New World agriculture. Based on the descriptive, ecological and geographical accounts of C. pepo subsp. texana in the wild, the idea is considered that the image was based on an offspring of a plant found growing along the Gulf Coast of what is now the United States.
Motoo Kimura (1924-1994).
Explore the source record for details and available documents.
UV-excited chlorophyll fluorescence as a tool for the assessment of UV-protection by the epidermis of plants.
Recently, a new method for estimating epidermal transmission of UV radiation in higher plants has been proposed. The empirical evidence for the usefulness of this method is reviewed here. Direct comparison with spectroscopically determined epidermal transmission yielded equivalent results. A linear correlation to the concentration of epidermal screening compounds has been shown. Relating UV-A and UV-B absorbance allowed some preliminary conclusions about the chemical nature of the screening compounds. A new portable apparatus is presented for the first time, which allows the non-destructive assessment of UV-A screening even under field conditions. Repeated measurements on identical leaves over a time-course of 6 d demonstrated a strong age-dependence in the capacity for the synthesis of UV-A screening compounds upon exposure to UV-B radiation. It is concluded that the new method may provide a valuable tool for the investigation of the acclimation of plants to UV-B radiation and, when accompanied by HPLC analysis, of the reaction of phenolic metabolism to environmental stimuli.
Luther Burbank: honorary member of the American Breeders' Association.
Explore the source record for details and available documents.
[Der gantzen Artzenei. Title page of a medical text by Johann Dryander (Frankfurt am Main, Christian Egenolph, 1542). Woodcut attributed to Hans Brosamer. New Haven, Yale Medical Library, Clements C. Fry Collection].
Explore the source record for details and available documents.
Andreas Cesalpini, Quaestionum peripateticarum, libri V, liber V, quaestio IV.
Explore the source record for details and available documents.
Gas exchange measurements, what can they tell us about the underlying limitations to photosynthesis? Procedures and sources of error.
The principles, equipment and procedures for measuring leaf and canopy gas exchange have been described previously as has chlorophyll fluorescence. Simultaneous measurement of the responses of leaf gas exchange and modulated chlorophyll fluorescence to light and CO2 concentration now provide a means to determine a wide range of key biochemical and biophysical limitations on photo synthesis in vivo. Here the mathematical frameworks and practical procedures for determining these parameters in vivo are consolidated. Leaf CO2 uptake (A) versus intercellular CO2 concentration (Ci) curves may now be routinely obtained from commercial gas exchange systems. The potential pitfalls, and means to avoid these, are examined. Calculation of in vivo maximum rates of ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco) carboxylation (Vc,max), electron transport driving regeneration of RuBP (Jmax), and triose-phosphate utilization (VTPU) are explained; these three parameters are now widely assumed to represent the major limitations to light-saturated photosynthesis. Precision in determining these in intact leaves is improved by the simultaneous measurement of electron transport via modulated chlorophyll fluorescence. The A/Ci response also provides a simple practical method for quantifying the limitation that stomata impose on CO2 assimilation. Determining the rate of photorespiratory release of oxygen (Rl) has previously only been possible by isotopic methods, now, by combining gas exchange and fluorescence measurements, Rl may be determined simply and routinely in the field. The physical diffusion of CO2 from the intercellular air space to the site of Rubisco in C3 leaves has long been suspected of being a limitation on photosynthesis, but it has commonly been ignored because of the lack of a practical method for its determination. Again combining gas exchange and fluorescence provides a means to determine mesophyll conductance. This method is described and provides insights into the magnitude and basis of this limitation.