As plant physiology increased steadily in the latter half of the 19th century, problems of absorption and transport of water and of mineral nutrients and problems of the passage of metabolites from one cell to another were investigated, especially in Germany. JUSTUS VON LIEBIG, who was born in Darmstadt in 1803, founded agricultural chemistry and developed the techniques of mineral nutrition in agricul ture during the 70 years of his life. The discovery of plasmolysis by NAGEL! (1851), the investigation of permeability problems of artificial membranes by TRAUBE (1867) and the classical work on osmosis by PFEFFER (1877) laid the foundations for our understanding of soluble substances and osmosis in cell growth and cell mechanisms. Since living membranes were responsible for controlling both water movement and the substances in solution, "permeability" became a major topic for investigation and speculation. The problems then discussed under that heading included passive permeation by diffusion, Donnan equilibrium adjustments, active transport processes and antagonism between ions. In that era, when organelle isolation by differential centrifugation was unknown and the electron microscope had not been invented, the number of cell membranes, their thickness and their composition, were matters for conjecture. The nature of cell surface membranes was deduced with remarkable accuracy from the reactions of cells to substances in solution. In 1895, OVERTON, in U. S. A. , published the hypothesis that membranes were probably lipid in nature because of the greater penetration by substances with higher fat solubility.

The plasma membrane is at once the window through which the cell senses the environment and the portal through which the environment influences the structure and activities of the cell. Its importance in cellular physiology can thus hardly be overestimated, since constant flow of materials between cell and environment is essential to the well-being of any biological system. The nature of the materials mov ing into the cell is also critical, since some substances are required for maintenance and growth, while others, because of their toxicity, must either be rigorously excluded or permitted to enter only after chemical alteration. Such alteration frequently permits the compounds to be sequestered in special cellular compartments having different types of membranes. This type of homogeneity, plus the fact that the wear and tear of transmembrane molecular traffic compels the system to be constantly monitored and repaired, means that the membrane system of any organism must be both structurally complex and dy namic. Membranes have been traditionally difficult to study because of their fragility and small diameter. In the last several decades, however, remarkable advances have been made because of techniques permit ting the bulk isolation of membranes from homogenized cells. From such isolated membranes have come detailed physical and chemical analyses that have given us a detailed working model of membrane. We now can make intelligent guesses about the structural and func tional interactions of membrane lipids, phospholipids, proteins, sterols and water."

As editor of the two-part Volume V on photosynthesis in RUHLAND'S Encyclopedia, the forerunner of this series published in 1960, I have been approached by the editors of the present volume to provide a short preface. The justification for following this suggestion lies in the great changes which have been taking place in biology in the two decades between these publications, changes which are reflected in the new editorial plan. Twenty years ago it appeared convenient and formally easy to consider photo synthesis as a clearly separated field of research, which could be dealt with under two major headings: one presenting primarily photochemical and biochemical prin ciples, the other physiological and environmental studies. Such a partition, however, as far as aims and opinions of the authors were concerned, resulted in a rather heterogeneous volume. Today, the tendency in experimental biology is towards a merger of previously distinct disciplines. Biochemists and biophysicists have developed their methods to such an extent that, over and above the analysis of individual reaction sequences, work on the manifold interrelationships among cellular activities has become in creasingly possible. Joining them in growing numbers are the physiologists and ecologists with their wealth of information on activity changes in vivo and on the variability and efficiency of the organisms concerned. Furthermore, biochemists, biophysicists and physiologists also now share a lively interest in ultrastructure research, the results and implications of which, through continually improving methodology, have generated important stimuli for the work in the field of cell function."

Proceedings of the NATO Advanced Study Institute, Pugnochiuso, Italy, June 22-July 3, 1986

Oxygen (O ) appeared in significant amounts in the Earth's atmosphere over 2. 2 2 billion years ago, largely due to the evolution of photosynthesis by cyanobacteria (Halliwell 2006). The O molecule is a free radical, as it has two impaired electrons 2 that have the same spin quantum number. This spin restriction makes O prefer to 2 accept its electrons one at a time, leading to the generation of the so-called reactive oxygen species (ROS). The chemical nature of these species dictates that they can create damage in cells. This has contributed to the creation of the "oxidative stress" concept; in this view, ROS are unavoidable toxic products of O metabolism and 2 aerobic organisms have evolved antioxidant defences to protect against this tox- ity (Halliwell 1981; Fridovich 1998). Indeed, even in present-day plants, which are full of antioxidants, much of the protein synthetic activity of chloroplasts is used to replace oxidatively damaged D1 and other proteins (Halliwell 2006). Yet, the use of the "oxidative stress" term implies that ROS exert their effects through indiscriminate widespread inactivation of cellular functions. In this context, ROS must not be able to react with lipids, proteins or nucleic acids in order to avoid any damage to vital cellular components. However, genetic evidence has suggested that, in planta, purely physicoche- cal damage may be more limited than previously thought (Foyer and Noctor 2005).

First published in 1975, this volume provides a unique comparative treatment of annual and seasonal photosynthetic production in both terrestrial and aquatic environments on a world scale and examines the efficiency with which incoming light energy is utilised in different types of natural and managed vegetation, including agricultural crops. It discusses the characteristics of the vegetation which determine this productivity, including such features as leaf or plant arrangement in relation to light interception, the photosynthetic activity of the individual leaves or other organs and the strategy of the plant in making use of assimilates for growth and development. Most professional ecologists and plant physiologists will find much to interest them here and the book should form valuable background reading for students in plant biology, ecology and agriculture.

This book gathers contributions presented during an In- ternational meeting organized by the Laboratory of Photobio- logy of the University of Liege, Belgium, on 8 and 9 August 1983. The general topic of the discussions was protochlorophyl- lide reduction and greening. Among the reasons for choosing this topic were the recent advances in the field. These ad- vances deal with: (1) The characterization of the basic constituents of the photoenzymatic complex responsible for protochlorophylli- de reduction. This complex is known to be ternary, comprising the pigment: protochlorophyllide, NADPH and the enzyme proto- chlorophyllide oxidoreductase. (2) The discovery of short-lived intermediates in the photoreduction process, and in particular, the recent findings resulting from the proqresses of the picosecond and nanosecond spectrometry. (3) The obtention of new data on the components of the plastids, on the changes they undergo during the first steps of greening, and on the distribution of the pigment-protein complexes between the various substructures of the etioplast. (4) The detection of early photoactivities apart from protochlorophyllide reduction. These subjects have ~cen extensively discussed during the meeting and several sections of this book are devoted to the presentation of the new data.

An International Symposium, Qiryat Anavim, Israel, January 9-12, 1984

The contributions of plant genetics to the production of higher yielding crops of superior quality are well documented. These successes have been realized through the application of plant breeding techniques to a diverse array of genetically controlled traits. Such highly effective breeding procedures will continue to be the primary method employed for the development of new crop cultivars; however, new techniques in cell and molecular biology will provide additional approaches for genetic modification. There has been considerable speculation recently concerning the potential impact of new techniques in cell and molecular biology on plant improvement. These genetic engineering techniques should offer unique opportunities to alter the genetic makeup of crops if applied to existing breeding procedures. Many questions must be answered in order to identify specific applications of these new technologies. This search for applications will require input from plant scientists working on various aspects of crop improvement. This volume is intended to assess the interrelationships between conventional plant breeding and genetic engineering.

Historically, scientists and laymen have regarded salinity as a hazar dous, detrimental phenomenon. This negative view was a principal reason for the lack of agricultural development of most arid and semi arid zones of the world where the major sources of water for biological production are saline. The late Hugo Boyko was probably the first scientist in recent times to challenge this commonly held, pessimistic view of salinity. His research in Israel indicated that many plants can be irrigated with saline water, even at seawater strength, if they are in sandy soil - a technique that could open much barren land to agriculture. This new, even radical, approach to salinity was clearly enunciated in the book he edited and most appropriately entitled 'Salinity and Aridity: New Approaches to Old Problems' (1966). A decade later, three members of the United States National Science Foundation (NSF), Lewis Mayfield, James Aller and Oskar Zaborsky, formulated the 'Biosaline Concept'; namely, that poor soils, high solar insolation and saline water, which prevail in arid lands, should be viewed as useful resources rather than as disadvantages, and that these resources can be used for non-traditional production of food, fuels and chemicals. The First International Workshop on Biosaline Research was con vened at Kiawah Island, South Carolina, in 1977 by A. San Pietro.

The Annual Beltsville Symposium provides a forum for interaction among scientists involved in research that has vital impact on agriculture and on the agricultural sciences. The 10th Symposium in the series, Biotechnology for Solving Agricultural Problems, focuses on the use of a revolutionary new set of tools, biotechnology, and attempts to define the set in terms of its applications in agriculture. Biotechnology has already contributed to the genetic improvement of agricultural products. Procedures that were impossible to test or to implement in the past because of technological limitations are now routinely used by many scientists. Four areas that have benefitted from advances in biotechnology are covered in the symposium proceedings. These areas include genetic manipulation, nutrition, health and disease, and natural resource management. The 31 invited speakers have identified programs of basic and applied research on plants, animals, and insects that fall within these broad areas. Their research strategies included such techniques as germline modification, gene mapping, monoclonal antibody production, and gene transposition. These strategies have tapped new well springs of information and technologies ranging from the regulation of gene expression (and with it, the regulation of development, growth, disease resistance, and nutrient metabolism) to degradation of pesticides and toxic wastes. The applications of biotechnology to agricultural research have opened virgin vistas with enormous potential. The new biotechnological techniques and those that will evolve with their use will contribute markedly to the capacity of the agricultural sciences to advance the well-being of the human race.

The idea of addressing the problem of the genetic specificity of mineral nutrition at an international level arose four years ago in a proposal for this topic to be included in the program of the II Congress of the Federation of European Societies for Plant Physiology (FESPP) as a separate section. The Organising Committee of the II Congress of FESPP which was held in Santiago de Compostella in 1980 arranged a special session and it was clearly successful. A special scientific meeting where the genetic aspects of plant nutrition in their widest sense could be presented and discussed comprehensively appeared to be necessary and that is how this Symposium came to be organized by the Serbian Academy of Sciences and Arts. Much progress has already been achieved in this field, and bearing in mind the importance of this problem, particularly at the present moment, it is necessary for us both to acquaint ourselves with what has been achieved so far, and even more to direct attention and effort to the fundamental problems for the future.

The Second International Oat Conference. of which these are the proceedings.was heldat Aberystwyth. 15-18 July.1985. In thebusiness meeting heldatthecloseof theFirstInternational Oat Workshop that was held at PennsylvaniaStateUniversity in 1982. an Internat i ona1 Organsi i ng Committee under the chairmanship of Or KJ Frey was electedto organisethe next conference.and Aberystwyth was proposed and agreed as the venue. The final date of the Second Conferenceand the out 1i ne of the programme. inc1udi ng selection of the rnain speakers. was agreed by the Internat i ona1 Committee but 1oca1 arrangements and finalisation of the programme were delegatedto a local sub-committee centredat the Welsh Plant Breeding Station. We wish to record our appreciationof the work done bythis localcommittee in assuming various organisational responsibilities. From the outsettherewas a firm committmentto makethe Conferenceas international as possible and every effortwas made both to provide a programme thatwouldattract participants from allpartsof the worldand to keep costs to a minimum so as to increasethe chances of potential delegatesbeing ableto attend. Alistof participantsis includedbut it is worthyof notethattwenty-three countr ies were represented. The Conferencewas organisedintoseven half-daysessions. Six of these covered differenttopics relevantto the improvement of oats and the seventhwas a visit to the Welsh PlantBreedingStationwhere laboratory and fieldwork ontheoatcrop was demonstrated.

The last 10 years have witnessed an explosion in our understanding of plant h- mones. The often vague models of hormone action developedover decadeshave been replaced in short order by detailed molecular models that include receptors and in many cases downstream signal transduction components. Given the rapid progress in understanding the mechanism of action of plant growth regulators, a technical review of hormone methodology is timely. Our book focuses on genetic, biochemical, ana- tical and chemical biological approaches for understanding and dissecting plant h- mone action. The greatest strides in plant hormone biology have come, by and large, from the use of genetic methods to identify receptors and we dedicate a chapter to general genetic methods of analysis using the model system Arabidopsis thaliana. A cluster of chapters focuses on biochemical methods for documenting interactions betweenhormonesand their receptors. Theimportance of these assays is tremendous; receptor-ligand interactions in animal model systems have been the cornerstones of pharmacological and medicinal chemical assays that have enabled identification of selective and non-selective agonists and antagonists that can be used to further probe and dissect questions of receptor function. This is likely to be a major new frontier in plant hormone research.

The present volume "Excitation Energy and Electron Transfer in Pho. tosynthesis" is dedicated to a colleague and dear friend Warren L. But ler. I first met Warren when he visited the University of Illinois at Ur bana during the early sixties; he left an indelible impression on me as a person with warmth and enthusiasm. Initially, he was someone I looked to for guidance, but later we also became friends. Whenever I passed through Los Angeles, I always telephoned Warren and often end ed up taking a plane to San Diego to stay with two wonderful people, Warren and his wife Lila. His invitations could never be refused. Below I reproduce the words of Herbert Stern on Warren L. Butler's life; these words express my sentiments as well as those of many of Warren's friends: ''A lifetime of acedemic creativity criss-crossed by streaks of highbrow and lowbrow fun. There is no summary to this adventure be cause we can neither make nor proclaim an end. Warren has bequeathed us his garden of academic treasures. It is ours to keep and tend. There is lots of joy in our many recollections of Warren's life and sorrow's foil can only brighten the brightness that the joy radiates."

Plant hormone research is the favorite topic of physiologists. Past three decades have witnessed that this subject has received much attention. The inquisitive nature of human mind has pumped much in literature on this subject and this volume is the product of such minds. In the following pages various hormonal-controlled physiological processes like, flowering, seed dormancy and germination, enzyme secretion, senes cence, ion transport, fruit ripening, root growth and development, thig momorphogenesis and tendril thigmonasty have been included. The volume also contains a review paper on 'Growth Regulating Activity of Penicillin in Higher Plants' and has been presented for the first time. The vast contents of each review paper have been written by erudite scholars who have admirably carried out their evangelic task to make the text up TO date. This volume, I am sure, would stimulate the appetite of researchers of peripheral disciplines of botany and agricultural sciences and they will continue to enjoy the fun and adventures of plant hormone research. Save one. my most outstanding debts are due to the rich array of the contributors and other plant physiologists specially to Prof. Thomas Gaspar (Belgium), Prof. E. E. Goldschmidt (Isreal), Prof. H. Greppin (Switzerland), Dr. K. Gurumurti (India), Prof. M. A. Hall (U. K. ), Prof. H. Harada (Japan), Dr. M. Kaminek (Czechoslovakia), Dr. J. L. Karm oker (BangIa Desh), Prof. Peter B. Kaufman (U. S. A. ), Dr. V. I. Kefeli . / (U. S. S. R. ), Dr. M. Kutaoek (Czechoslovakia), Prof. S."

Forty years ago, when PLANT AND SOIL first appeared, Europe was still recovering from the devastating effects of World War II. During the war years, work in many centres of agricultural research had come to a virtual standstill. Buildings and equipment were destroyed, scientists were often forced to terminate their research and teaching activities and funds allocated to such work were diverted to other, at that time, more pressing needs. During the first post-war years reconstruction was undertaken with great zeal and in that light the founding of the new journal PLANT AND SOIL must be viewed. In the pre-war period most agricultural science journals were still primarily national ones and consequently many articles were published in languages mastered by only a limited number of potential readers. In small countries whose languages are not widely understood, the desire arose to publish research findings in one of the major languages. It is therefore understandable that in the early years of the journal's existence, large portions of PLANT AND SOIL were filled with articles from the Scandinavian countries and The Nether lands. Originally, rather frequent use was made of the opportunity to publish also in German and French, but with the advance of English as a major language of communication, a decline was noticeable in the number of German and French manuscripts submitted. As a consequence the Edi torial Board has recently decided to terminate the publishing of articles in these languages."

Thi s book is a general introduction into in vivo chlorophyll fluorescence and contains the contributions of the first International Ch 1 orophyll Fluorescence Sympos i urn he 1 din the Phys i kzentrum Bad Honnef, F. R. G. from June 6 to 8, 1988. This Symposium was made possible by a generous support from the Wilhelm and Else Heraeus Foundation, Hanau, which is gratefully acknmvledged. The book not only comprises all aspects of the applications of chlorophyll fluorescence in photosynthesis, stress physiol ogy, hydrobiology and remote sensing, but also gives access to measuring techni ques, data acqui si ti on and earl i er 1 iterature references. Thus it is far more than just a common proceedings book, it is a general introduction to all forms of application of the non-destructive in vivo chlorophyll fluorescence including the newest results. In a first chapter the inverse correlation between in vivo chlorophyll fl uorescence and photosynthet i c quantum convers i on and CO? -ass i mi 1 at ion is outlined, the origin and life-time of the chlorophyll fluOrescence at room and liquid nitrogen temperatures are given as well as the induction kinetics (Kautsky effect) and the methodo 1 ogi ca 1 approaches to regi ster different forms of chlorophyll-fluorescence signatures."

These volumes contain an excellent, up-to-date review of the rapidly developing field of photosynthesis research. They comprise the proceedings of the Ninth International Congress on Photosynthesis, held in Nagoya, Japan, in 1992, which was the first in the series to be held in Asia. The Congress was attended by over 1000 active participants from 43 countries, who contributed plenary lectures, symposium talks, posters and discussions. The volumes contain most of these contributions, in the form of review papers and short communications, assembled in 26 chapters, which cover a wide variety of subjects, such as: fundamental aspects, excitation energy transfer, primary reactions, bioenergetic processes, carbon metabolism, and its metabolic and genetic regulations; applied aspects, herbicides and artificial photosynthesis, and environmental aspects, photosynthesis under stress conditions and global climate change. Research in Photosynthesis is therefore an important document, containing the latest high-level information about photosynthesis in its broadest sense. The four volumes are a valuable reference source. Furthermore, the volumes are important for background study for those enetering this exciting and promising field of investigation.

The Second International Congress on Photosynthesis Research took place in Stresa, Italy during June 24-29, 1971; two centuries after the discovery of Photosynthesis by Joseph Priestley in 1971. This important anniversary was celebrated at the Congress by a learned account of Priestley's life and fundamental discoveries given by Professor Robin HILL, F. R. S. Professor HILL's lecture opens the first of the three volumes which contains the contributions presented at the Congress. The manuscripts have been distributed into three volumes. Volume I con tains contributions in the areas of primary reactions and electron transport; Volume II ion transport and photophosphorylation, and Volume III carbon assimilation, regulatory phenomena, developmental aspects, and from the two special sessions of the Congress devoted to evolution and photorespiration. It is realized that this division is necessarily somewhat arbitrary since many contributions relate to more than one of the above mentioned titles. However, the large number of contributions (over 3000 typed pages) made it impossible to publish the proceedings in less than three volumes. The printing of these volumes and the organization of the Congress were made possible by a contribution from the Consigio Nazionale delle Ricerche of Italy. The generous support of the Istituto Lombardo Acca demia di Scienze e Lettere to the publication of these proceedings is gratefully acknowledged. The editors wish to express their appreciation to all the scientists who contributed the results of the investigations, for their coopera tion; and to Drs."

For centuries biologists have been extremely interested in the structure of desert plants as examples of natural selection to harsh environmental conditions. Indeed, desert plants are frequently used as examples in many biology classes and textbooks to illustrate natural selection, but this has led to an unfortunate litany of errors and misconceptions about desert plant adaptations.
This new synthesis focuses on plants of lowland tropical and subtropical arid deserts. Readers will be surprised to discover that many features commonly ascribed to desert plants are rareley observed in the most common species. Instead, the typical structural adaptations of nonsucculent warm desert plants are now viewed as ways to maximize photosynthetic rate.

The period following the second world war has witnessed an expanding commitment to incr~ased food production in tropical countries. Public and private initiatives at the national and international levels have led to the creation of programs geared specifically towards the improvement of food crops in tropical conditions. Examples of this increased commitment are the network of international agricultural research centers and numerous bilateral aid projects. As a consequence, crop improvement has become a truly worldwide endeavor, relying on an international network of institutions and collaborators. This holds also for Phaseolus beans. Following the discovery of the Americas, Phaseolus beans became distributed on all six continents. Yet, until not so long ago, most of the research on Phaseolus improvement took place in developed countries. In recognition of the nutritional importance of Phaseolus beans in developing countries, this has changed considerably in the last years, principally perhaps through the activities of the Centro Internacional de Agricultura Tropical (CIAT) and the International Board for Plant Genetic Resources (IBPGR). Consequently, the scope of the research on Phaseolus has broadened considerably and the number of Phaseolus researchers is larger than ever before.

Taking readers out of the laboratory and into the humid tropical forests, this comprehensive volume explores the most recent advances occurring in tropical plant ecophysiology. Drawing on the knowledge of leading practitioners in the field, this book synthesizes a broad range of information on the ways in which tropical plants adapt to their environment and demonstrate unique physiological processes. This book is arranged into four sections which cover resource acquisition, species interactions, ecophysiological patterns within and among tropical forest communities, and the ecophysiology of forest regeneration. These sections describe plant function in relation to ecology across a wide spectrum of tropical forest species and growth forms. How do different species harvest and utilize resources from heterogeneous tropical environments? How do patterns of functional diversity reflect the overwhelming taxonomic and morphological diversity of tropical forest plants? Such fundamental questions are examined in rich detail. To illuminate the discussions further, every chapter in this book features an agenda for future research, extensive cross referencing, timely references, and the integration of ecophysiology and the demography of tropical species where the data exist. Tropical Forest Plant Ecophysiology provides plant scientists, botanists, researchers, and graduate students with important insights into the behavior of tropical plants. Biologists and foresters interested in tropical ecology and plant physiological ecologists will also benefit from this authoritative and timely resource.