The study of plant development in recent years has often been concerned with the effects of the environment and the possible involvement of growth substances. The prevalent belief that plant growth substances are crucial to plant development has tended to obscure rather than to clarify the underlying cellular mechanisms of development. The aim in this book is to try to focus on what is currently known, and what needs to be known, in order to explain plant development in terms that allow further experimentation at the cellular and molecular levels. We need to know where and at what level in the cell or organ the critical processes controlling development occur. Then, we will be better able to under stand how development is controlled by the genes, whether directly by the continual production of new gene transcripts or more indirectly by the genes merely defining self-regulating systems that then function autonomously. This book is not a survey of the whole of plant development but is meant to concentrate on the possible component cellular and molecular processes involved. Consequently, a basic knowledge of plant structure is assumed. The facts of plant morphogenesis can be obtained from the books listed in the General Reading section at the end of Chapter 1. Although references are not cited specifically in the text, the key references for each section are denoted by superscript numbers and listed in the Notes section at the end of each chapter."

The behavioral neuroscience of thirst and sodium appetite are research ventures that have expanded dramatically in recent years. Work done in the mid-1950s and early 1960s made it clear that drinking behavior could be affected by direct manipulations of the brain, especially by brain damage and by pharmacological treat ments. Since that. time experimental approaches have diversified and the research enterprise has attracted the interest of a broad international community of scientists. Many aspects of both thirst and sodium appetite are being studied. The most prominent of these are: 1) phylogenetic and ontogenetic aspects of the phenomena of drink ing behavior, 2) the mechanisms of a variety of dipsogenic and antidipsogenic treatments, both drugs and hormones, 3) the biological controls of drinking and their interaction with the regulation of blood volume and blood pressure, 4) the peripheral signals of drinking including the role of the baro- and volume-receptors, 5) the receptor systems within the brain and the neuroanatomical circuitry for thirst and sodium appetite, and 6) the possible roles of brain sodium and of the hormones of sodium conservation ln the arousal of sodium appetite. This acceleration of basic research activity has given in sights into the clinical disorders of thirst and salt appetite and has produced pharmacological agents of potential therapeutic use."

Jointly published with INRA, Paris.
The application of new production methods in the food industry - genetic engineering in plants and animals - as well as recent crises over food-borne diseases have led consumers to a growing concern about science as an appropriate basis for developing sound agricultural policies. This book presents the discussion of scientists and politicians in the framework of an OECD programme conference on how to restore public trust in the application of new scientific achievements concerning food production.

This volume of the series The Plant Viruses is devoted to viruses with rod-shaped particles belonging to the following four groups: the toba moviruses (named after tobacco mosaic virus), the tobraviruses (after to bacco rattle), the hordeiviruses (after the latin hordeum in honor of the type member barley stripe mosaic virus), and the not yet officially rec ognized furoviruses (fungus-transmitted rod-shaped viruses, Shirako and Brakke, 1984). At present these clusters of plant viruses are called groups instead of genera or families as is customary in other areas of virology. This pe culiarity of plant viral taxonomy (Matthews, 1982) is due to the fact that the current Plant Virus Subcommittee of the International Committee of Taxonomy of Viruses is deeply split on what to call the categories or ranks used in virus classification. Some plant virologists believe that the species concept cannot be applied to viruses because this concept, according to them, necessarily involves sexual reproduction and genetic isolation (Milne, 1984; Murant, 1985). This belief no doubt stems from the fact that these authors restrict the use of the term species to biological species. According to them, a collection of similar viral isolates and strains does constitute an individ ual virus, i. e., it is a taxonomy entity separate from other individual viruses."

This book is an outgrowth of a much earlier book, Farm Structures, by H. J. Barre and L. L. Sammet, published by John Wiley & Sons in 1950 as one of a series of textbooks in agricultural engineering spon sored by the Ferguson Foundation, Detroit, Michigan. Light Agricul tural and Industrial Structures: Analysis and Design will be useful as an undergraduate student textbook for junior-or senior-level compre hensive courses on structural analysis and design in steel, wood, and concrete, and as a reference work for practicing engineers. Emphasis is on basic analysis and design procedures. The book should be useful in any country where there is a need to design structures for agricul tural production and processing. It is assumed that readers have had prerequisite course work in engineering mechanics and strength of materials as typically taught to undergraduate engineering students. The scope of this book is wide; it might be difficult for instructors and students to cover all of the chapters in a typical three credit-hour course. The instructor will need to assess his own situation and scheduling constraints. More or less time could be spent on chapters one through five, depending on the capability the students already have in analysis of statically deter minate and indeterminate structures. Two to three weeks might then be allocated for study of each of the last six chapters dealing with design in steel, reinforced concrete, and wood."

Genetics and Genomics of Populus provides an indepth description of the genetic and genomic tools and approaches for Populus, examines the biology that has been elucidated using genomics, and looks to the future of this unique model plant. This volume is designed to serve both experienced Populus researchers and newcomers to the field. Contributors to the volume are a blend of researchers, some who have spent most of their research career on Populus and others that have moved to Populus from other model systems. Research on Populus forms a useful complement to research on Arabidopsis. In fact, many plant species found in nature are - in terms of the life history and genetics - more similar to Populus than to Arabidopsis. Thus, the genetic and genomic strategies and tools developed by the Populus community, and showcased in this volume, will hopefully provide inspiration for researchers working in other, less well developed, systems.

The original aim of this book was to cover different aspects of the tradi tionally "filamentous" potex-, carla-, poty-, clostero-, and capilloviruses. The title The Filamentous Plant Viruses seemed the only suitable one, but it has led us to discuss also the quite different filamentous viruses of the rice stripe group-recently officially named the tenuivirus group which otherwise, indeed, might not have been conveniently covered in any volume of this series. The question must be asked: What is there new that justifies the presentation of a book of this kind? An outline of the answer may be Among the traditional filamentous viruses, much pro given as follows. gress has been made in elucidating the physical structure of potexvirus particles, and this work serves as an excellent model for discussion of and future experiments on the poty-, carla-, clostero-, and capilloviruses, which have comparable structures, although they are more difficult to manipulate. Work on the structure and strategy of the genomes of poty viruses is, however, relatively advanced and at a very interesting stage. The helper component that assists the aphid transmission of potyviruses has also recently received considerable attention, although the more we know about that, the less seems clear about the aphid transmission of the carlaviruses and closteroviruses, which apparently neither possess nor require a helper component."

Drawing from a decade-long collaboration between Japan and Russia, this important volume presents the first major synthesis of current knowledge on the ecophysiology of the coniferous forests growing on permafrost at high latitudes. It presents ecological data for a region long inaccessible to most scientists, and raises important questions about the global carbon balance as these systems are affected by the changing climate.

Making up around 20% of the entire boreal forests of the northern hemisphere, these permafrost forest ecosystems are subject to particular constraints in terms of temperature, nutrient availability, and root space, creating exceptional ecosystem characteristics not known elsewhere. This authoritative text explores their diversity, structure, dynamics and physiology. It provides a comparison of these forests in relation to boreal forests elsewhere, and concludes with an assessment of the potential responses of this unique biome to climate change.

The book will be invaluable to advanced students and researchers interested in boreal vegetation, forest ecology, silviculture and forest soils, as well as to researchers into climate change and the global carbon balance. "

Like many genetic engineers, I have recently been receiving the atten tion of various venture capital companies, international drug houses and Members of Parliament. I will not discuss which of these approaches are most welcome, but it did cause me to consider the speed of advance in genetic engineering, and the implications of this rapid growth. There were few who anticipated it - only five years ago, most scientists thought applications would come at the end of the century, yet we see products such as insulin and interferon already available for clinical testing. In Europe in general and Britain in particular, this explosive growth in our own field has coincided with a general industrial depression and a marked reduction in funding for biomedical research. The brain drain from Britain is a serious matter, for we are losing the best of our younger scientists, on whom we would rely to train the next generation of molecular biologists. These volumes have come from British labs (mostly because I happen to be based in London, and my contacts and friends are here), and I feel that the quality of the con tributions also shows that our current research is of a high standard.

With one volume each year, this series keeps scientists and advanced students informed of the latest developments and results in all areas of the plant sciences.
The present volume includes reviews on genetics, cell biology, physiology, comparative morphology, ecology and vegetation science.

After the publication of the Diagnostic Manual for the Identification of Insect Pathogens, the authors received many queries asking why they had not included the larger metazoan parasites as well as the microbial forms. An examination of the literature indicated that pictorial guides to the identification of nematodes and the immature stages of insect parasites were unavailable. Consequently we decided to rewrite the sections cover ing insect pathogens and combine these with new sections on ento mogenous nematodes and the immature stages of insect parasites. The result is the present laboratory guide, which is unique in covering all types of biotic agents which are found inside insects and cause them injury or disease. Included as parasites are insects and nematodes. Among the pathogens included are viruses, rickettsias, bacteria, fungi, and protozoans. Emphasis is placed on identification with an attempt to use the most easily recognizable characters. Use of a certain number of technical terms is unavoidable, and explanations of these can be found in most biological dictionaries or the glossary of invertebrate pathology prepared by Steinhaus and Martignoni (1970).

The biomedical community often complains of the crowded schedule of important meetings to be attended. It was thus with some reser vations when the individuals participating in this conference accepted the invitation to attend a small gathering to discuss the "Comparative Pathophysiology of Circulatory Disturbances," held over three days in November, 1971. At the end of it they had changed their minds and were enthusiastic over the wisdom to hold meetingsof this kind. The conference was conceived some years earlier when it was apparent to the conveners that little opportunity exists in the common mammoth meetings to exchange detailed information and, p- haps more importantly, to transmit points of view between scientists of different disciplines. In particular, the voice of veterinarians and comparative biologists is not often heard by medical investigators, and vice versa. Thus, many animal models exist in nature whose investigative exploitation might make important contributions to an understanding of human disease, yet they are unknown to medical scientists. Conversely, veterinarians are often not aware of the needs of such models and their recognition is often delayed unduly. This conference, attended by investigators of various back grounds was called to help correct these deficiencies, at least in a small segment of study, that concerned with circulatory pathophysiology."

The International Society on OXygen Transport to Tissue (ISO'IT) has canpleted nine years as a society since its first fonnal meeting at Charleston-Clanson, South Carolina, United States of America in 1973. Prior to this time an active group of scientists and engineers rret in w:: >rkshop environrrents, on a periodic basis, around the w:: >rld. Meetings are ncM on an annual basis, alternating between Europe and the United States. The international gatherings include scientists and engineers in a variety of fields. ISOIT has produced a stable forum for the exchange of info: rmation on the rnicroenvirornnent of living cells, ranging fran the utilization of mathematics and engineering, through physiology and radiobiology, to clinical applications. The proceedings of these meetings have been codified into six books, four of them published by Plenum Press in its prestigious Advances in Experimental Medicine and Biology series. This volume, together with the next two volumes that will follCJV.l the meetings in Dortmund, Gennany in 1982 and in Ruston, Louisiana in 1983 will provide further chapters in the history of this fascinating field of knCJV.lledge. OUr thanks are given to all the participants and contributors to the Detroit meeting. We hope that the strength of the society will grow in caning years, and that our contribution will eventually be felt in: inproving the treatment of the sick, and in enhancing the thought processes of the intellectual.

Modern forest products research had its start hardly fifty years ago. Today we are in a position to apply the title "wood science" to the field of wood technology that is based on scientific investigation, theoretical as well as experimental. It is this research that fosters new uses for wood as a raw material and that creates the foundation for new industries for the manufacture of wood-base materials such as plywood, laminated products, particle and fiber board and sand wich construction. Wood technology in its broadest sense combines the disciplines of wood anatomy, biology, chemistry, physics and mechanical technology. It is through this interdisciplinary approach that progress has been made in wood seasoning, wood preservation methods, wood machining, surfacing and gluing, and in the many other processes applied in its utilization. In 1936 the senior author published a book entitled, "Technologie des Holzes," which was a first approach to a universal reference book on wood technology. The first edition of Volume I of the Textbook of Wood Technology, co-authored by H. P. BROWN, A. J. P AN SHIN, and C. C. FORSAITH, was published in 1948. An indication of the rapid development of this field can be gained from the fact that the second edition of "Technologie des Holzes und der Holzwerkstoffe," completely revised, was needed by 1951. It contains 2233 pages compared with the 764 pages of the 1936 edition."

Outside Russia very little is known about the terrestrial ecology, vegetation, biogeographical patterns, and biodiversity of the enormously extensive ecosystems of Yakutia, Siberia. These systems are very special in that they function on top of huge layers of permafrost and are exposed to very severe and extreme weather conditions, the range between winter and summer temperatures being more than 100 degrees C. The soils are generally poor, and human use of the vegetation is usually extensive. Main vegetation zones are taiga and tundra, but Yakutia also supports a special land and vegetation form, caused by permafrost, the alas: more or less extensive grasslands around roundish lakes in taiga. All these vegetation types will be described and their ecology and ecophysiological characteristics will be dealt with. Because of the size of Yakutia, covering several climatic zones, and its extreme position on ecological gradients, Yakutia contains very interesting biogeographical patterns, which also will be described. Our analyses are drawn from many years of research in Yakutia and from a vast body of ecological and other literature in Russian publications and in unpublished local reports. The anthropogenic influence on the ecosystems will be dealt with. This includes the main activities of human interference with nature: forestry, extensive reindeer herding, cattle and horse grazing, etc. Also fire and other prominent ecological factors are dealt with. A very important point is also the very high degree of naturalness that is still extant in Yakutia's main vegetation zones.

This is the third annual compendium of a Technical Session of the Physiology Working Group of the Society of American Foresters held at the National Convention. Specialists in a dedicated area of tree physiology were invited to prepare chapter contributions synthesizing the status of knowledge in their area of expertise. Plant growth regulators (PGRs) was selected as the topic for in-depth examination at the 1986 Technical Session because a knowledge of how these "secondary messengers" regulate tree morphogenesis is vital to applications of biocontrol and biotechnology. Plant growth regulators have been the subject of numerous reviews in recent years. However, few have dealt specifically with woody perennials, and they are generally confined to single processes and/or organs. This volume attempts to provide a more comprehensive treatise of PGRs as they influence various ontogenetic events in forest trees. Reproductive physiology, both sexual and asexual, is emphasized because of its relevance to current efforts directed at increasing efficiency in the breeding and production of genetically improved trees for reforestation. The chapters on vegetative growth will be of interest to silviculturists and urban foresters as they consider cultural treatments in the management of forests and individual trees for specific products and purposes. This book should serve as a valuable text and source of reference for students, researchers and other professionals interested in gaining a better understanding of PGRs. The reader, however, who expects definitive answers to how PGRs function or can be used to control specific processes is likely to be disappointed.

There are clearly many directions in which the further development of the GUS gene fusion system can progress. Some of these have been outlined above, but others can be imagined. There are no reasons to limit our conceptions of the use of GUS gene fusions to analysis and manipulation of single genes. We can envision numerous marked genes - perhaps with several new fusion systems - giving valuable information about gene interaction, or population structure. The study of plan- pathogen and plant symbiont interactions can progress rapidly with simple quantitative markers for genes and individuals. We can imagine ways of using gene fusions to report on crop physiology or other complex phenotypes, thereby enhancing the accuracy and speed of screening. Introduction of the biosynthetic pathway for glucuronide detoxification by expressing genes for the UDP-glucuronyl transferases in plants may result in novel mechanisms for plants to deal with xenobiotics such as insecticides or herbicides. Synthesis of substrates, which until now has been performed chemicall- resulting in expensive compounds - can be done biosynthetically. This should make the system not only the most powerful gene fusion system for agriculture, but also the most accessible.

Dutch elm disease is a significant problem in forestry and horticulture which has proven remarkably difficult to ameliorate. Since the introduction of the Dutch elm disease pathogen to North America, the disease has devastated the elm population of this continent and has been the subject of intensive research. This book summarizes the range of approaches that have been taken to address the disease, and emphasizes the significant progress over the past decade in applying methods from cell and molecular biology. Dutch Elm Disease: Cellular and Molecular Approaches will be of interest to scientists in plant pathology, horticulture, forestry, biological control, and plant breeding.

Chemistry of Plant Protection, Volume 7, provides critical review articles on new aspects of herbicide resis- tance, serving the needs of research scientists, pesticide manufacturers, government regulators, agricultural practitioners.

Broadleaved evergreen forests where holm oak (Quercus ilex 1.) is almost the only canopy tree are a distinctive ecosystem of the Mediterranean Basin. Biogeographically, these forests lie between cool-temperate deciduous forests to the north and drier shrublands to the south. In a more general view, they are ecologically intermediate between these deciduous forests and humid warm-temperate evergreen forests, such as the laurisilva of the Macarone- sian islands or the broadleaved evergreen forests of eastern Asia. Holm oak forests are characterized by small-stature trees (usually 5 to 12 m tall), which are slow growing, cast a deep shade, and have small, evergreen, sclerophyl- lous leaves. Summer drought is the major environmental constraint. Mediterranean broadleaved evergreen forests have been underrepre- sented in the open literature. For example, The Woodlands Data Set of the International Biological Program (IBP) contained data from just one holm oak forest plot, Le Rouquet in southern France (Reichle 1981). Also, some models of European forests consider just two major forest types, broad- leaved deciduous and evergreen conifers, forgeting the extensive forests and woodlands of holm oak and cork oak (Quercus suber 1.), which are the ma- jor evergreen oak tree species in the Mediterranean Basin. The extensive lit- erature on Mediterranean-type ecosystems has also largely neglected these forests, being centred mostly on Mediterranean-type shrublands.

Since the middle of the Sixties, new types of formulation for biologically active com pounds have been developed, which have been introduced into the literature under the term Controlled Release Formulations (CRF). Stimulated by results from former and successful pharmaceutical research, which was engaged in the production of prepa rations with protracted effects (introduction onto the market in the year 1952 of D amphetamine in the form of pellets, coated to varying degrees with fats and waxes) 1), experiments were carried out to transfer the prolongation of effectiveness to pesticidal substances also, by means of a depot formulation. Initial work was concerned with the production of protective coatings for sonar systems in marine ecosystems. By means of antifouling paints or rubber coatings containing tri-n-butyl-tin oxide (TBTO), the growth of marine organisms on sonar domes, buoys and hulls in the water could be effectively prevented 2. 3). Controlled release formUlations of pesticides are defined as depot systems which continuously release their toxic constituents into the environment over a specified period of time (usually months to years) 4). According to this definition, such formu lations can be successfully employed where a chronic exposure to biologically active compounds is required over a longer period. The following hypothetical example is intended to illustrate this 5). In Fig. 1, the duration of activity of a non-persistent pesticide with a loss rate under environmental conditions of t1/2 = 15 days, is graphically illustrated."

Drawing upon a wealth of past research and results, this book provides a comprehensive summary of state-of-the-art methods for empirical modeling of forest trees and stands. It opens by describing methods for quantifying individual trees, progresses to a thorough coverage of whole-stand, size-class and individual-tree approaches for modeling forest stand dynamics, growth and yield, moves on to methods for incorporating response to silvicultural treatments and wood quality characteristics in forest growth and yield models, and concludes with a discussion on evaluating and implementing growth and yield models.

Ideal for use in graduate-level forestry courses, this book also provides ready access to a plethora of reference material for researchers working in growth and yield modeling.

"

Traditionally, intercellular communication and the regulation of biological functions of the body have been considered the role of two major and distinct systems: the nervous system and the endocrine system. The classic nervous system transmitted its signal rapidly by using electrical currents, whereas the signals used by the endocrine system were hormones produced by endocrine glands which reached the target tissues via the blood stream. During the past few decades, it has become apparent that these systems of intercellular com munication are not distinct and the signal messenger molecules are not unique to one or the other system. Many classic endocrine hormones are found in and act on nervous tissues and evidence exists for their de novo synthesis by neural related tissues. An exciting development in this area is the possibility that insulin and insulin-like growth factors (IGF) are not only produced by neural tissues but also exert profound physiological and biochemical effects on these tissues. The area of investigation of CNS insulin and IGF has been expanding rapidly and the availability of this book complete with up-to-date reviews on the subject by leaders in the field allows other scientists to utilize the knowledge in planning and adapting the latest ideas for future experiments. In addition, the book provides a collection of up-to-date articles for teachers to be used for the latest instructional material. The first section of the book covers general aspects of insulin receptors and insulin action."

Living Nature, not dull Art Shall plan my ways and rule my heart -Cardinal Newman Nature and Art 1868 One of the ineluctable consequences of growth in any field of science is that subjects of inquiry once established tend to give birth to subsubjects and that the subsubjects once established will in time undergo further mitotic division. Not so many years ago, problems surrounding the ietus and newly born infant lay in a realm almost to be described as a "no-man's land." Obstetricians properly gave major consideration to understanding and learning about processes and disorders concerned with maternal health and safety. The welfare of the infant was regarded as of secondary importance. Pediatricians on their part hesitated to invade the nursery, a sanctum regarded as belonging to the domain of the accoucheur. And the pathologist, enveloped in the mysteries of life and death in the adult, found scant tim~ for the neonate and the placenta.

The last decade has seen tremendous progress in our knowledge of the pollen development and gene expression on one hand and the characterization of pollen specific proteins on the other. In compiling the chapters for this volume, we have pragmatically categorized these basic developments in pollen molecular biology and biotechnology into two sections based on their applications in agricul ture and implications in medicine. Pollen developmental biology and gene expression: applications in agricul ture. Pollen development is an extremely complex process encompassing a series of biochemical, physiological and genetic events. At the basic level, sporophyt ically expressed genes may expound our knowledge of unique processes of cellular differentiation which ultimately give rise to a full-fledged organism. At the applied level, the studies on the pollen and male sporophyte-specific gene expression, and of promoters and transcription factors of relevant genes have the potential to manipulate the fertility in certain cash crops leading to agricultural biotechnology."