Chemicals that control plant growth have long been treated like a poor re lation of the herbicides yet in one manner of thinking, herbicides them selves are but one facet of the entire picture of plant growth regulation - a major fraction, to be sure, economically. It is now time to recognize that plant growth regulators should occupy an increasingly important role in agriculture. Sufficient numbers of uses having considerable economic re turn have already become established: (a) to increase the latex flow in the rubber trees; (b) to ripen sugarcane; (c) to control sprouting in onions and potatoes; (d) to shorten and strengthen wheat stems to prevent lodging; (e) to prevent premature deterioration; and (f) to permit control of timing for maximum utilization of crops. In addition, as energy becomes more difficult and costly to obtain, plant growth regulators will play an increasingly important role in energy conser vation as a result of increased yields due to their use . . There are a number of ways to present to the reader the role and effec tiveness of plant growth regulators. The one chosen here is to emphasize the effects on plant functions such as the induction of roots, the control of flowering, the control of sex, and the control of aging. Little emphasis has been placed on the basic research that has served as a background for the successes and potential successes discussed herein. N or is much attention paid to the mode of action of the various regulators."

A number of interdisciplinary fields related to "Plant Cell " "Biotechnology" are discussed. The two main directions are: Plant cell culture in agricultural applications for the improvement of crops and industrial applications in the production of secondary metabolites. A number of areas such as physiological and biochemical aspects of autotrophic cells, gene characterization in higher plants, transformation of plant cells, genetic stability in plant cell cultures, somatic hybridization and somatic embryogenesis are treated. Recent knowledge on somaclonal and gametoclonal variation as well as on the obtainment of protoplasts and their use for the isolation and culture of heterocaryons as tools for plant breeding are considered. Furthermore, the knowledge on biomass production in fermentor conditions and the role of immobilization for increased production and scale-up of plant cells are discussed.

Comprising about one hundred plates this atlas documents and describes the processes concerning the sexual reproduction in higher plants. It is dividedinto three parts: - Anther Development - Pistil Development - Progamic Phase and Fertilization. The scanning, transmission electron and light micrographs are all of immaculate quality and - for the viewer's orientation - almost each plate is complemented by a scheme showing a larger area of the plant indicating the site of the section. Together with instructive texts, the often striking images provide a valuable introduction into plant reproductive cell structures for researchers and advanced students of genetics, plantbreeding and cell biology.

Since the late 1960s the Indonesian state of East Kalimantan has witnessed a marked increase in the impact of human activities chiefly commercial logging and agricultural exploitation. Located on the island of Borneo, East Kalimantan also was subjected to prolonged droughts and extensive wildfires in 1982-83 and 1997-98 that were linked to the El Nino-Southern Oscillation (ENSO) phenomenon. The changes in the rainforest ecosystem in East Kalimantan during this 15-year cycle of severe ENSO events are the subject of this book. With an eye toward development of rehabilitation techniques for sustainable forest management, the authors examine possible interactive effects of drought, fire, and human impacts on the flora and fauna of the area.

Proceedings of the Physiology Working Group Technical Session Society of American Foresters National Convention, Portland, Oregon, USA, October 16-20, 1983

The Advanced Series in Agricultural Sciences is designed to ftll a long-felt need for advanced educational and technological books in the agricultural sciences. These texts, intended primarily for students of agriculture, should also provide up-to-date technical background reading for the many agricultural workers in extension services, educational systems, or international bodies. The editors of Advanced Series in Agricultural Sciences will select key subjects relating to the agricultural environment, agricultural physics and chemistry, soil science, plant sciences, animal sciences, food technology, and agricultural engineering for a critical and synthetic appraisal. An initial theoretical presentation will be used by authors of individual volumes in the series to develop a technical approach-including examples and practical solutions- to each subject. In addressing the advanced undergraduate and early graduate student of agriculture, selected authors will present the latest information, leavened with the lessons learned from their own experience, on precise and well-defined topics. Such books that widen the horizons of the student of agriculture can serve, too, as useful reference sources for the young specialist in the early years of his career. Many specialists who are involved in teaching agricultural science are isolated from universities and research institutions. This series will bring them up-to-date scientific information, thus keeping them in touch with progress. The basic objective of Advanced Series in Agricultural Sciences is to effect a structural integration of the theoretic and technical approaches to agriculture.

As a result of the green revolution, the use of yield-increasing inputs such as fer tilizer and pesticides became a matter of course in irrigated rice farming in Southeast Asia. Pesticides were applied liberally, both as a guarantee against crop failure and as a means of fully utilizing the existing yield potential of the crops. However, since outbreaks of pests, such as the brown planthopper (BPH) or the tungro virus, continued to occur despite the application of chemicals, a change of approach began to take place. It is now being realized more and more in Southeast Asia that crop protection problems cannot be resolved solely by the application of chemicals. In the past several years, increasing efforts have there fore been made to introduce, as a first step, supervised crop protection, leading gradually to integrated pest management (Kranz, 1982). Although the crop protection problems naturally differ in the different devel oping countries in Southeast Asia, the economic situation prevailing in these countries can nevertheless be regarded as an important common determinant: pesticide imports use up scarce foreign currency and thus compete with other imports essential to development. For the individual rice farmer, the problem is basically the same: his cash funds are limited and he must carefully weigh whether to use them for purchas ing pesticides, fertilizer or certified seed. In view of this constraint, it is becom ing necessary to abandon the purely prophylactic, routine calendar spraying and instead, employ critically timed and need-based pesticide applications."

Biotechnology has come to a stage where, by replacing some of the age old practices of breeding, it can produce novel and improved plants and animals that can better serve human beings and their purposes. The techniques of cellular and subcellular engineering, such as gene splicing and recombinant DNA, cloning, hybridomas and monoclonal anti bodies, production of human insulin, protein engineering, industrial fermentation, artificial insemination, cryopreservation and ovum trans fer, plant tissue culture and somatic hybridization, nitrogen fixation, phytomass production for biofuels etc have advanced greatly in the past decade, due to the availability of better equipment and the consolida tion of knowledge. Product orientation has removed biotechnology from the area of pure academic interest to one of utility where the final product is a spur to action. Businesses have started pouring money into projects, which has aided greatly in improving equipment, information exchange, and arousing the interest and imagination of the public. The common goal of science, industry and the public opens wide vistas and great hopes for biotechnology. The business of biotechnology addresses itself to issues of factory farming, technology transfer, joint ventures, international cooperation and to specific topics as well as the produc tion of diagnostic kits. Industry is particularly concerned with the phar maceutical field and microbial biotechnology from which profitable return can accrue. Commercial interests have led to better management practices and systematisation."

The world needs for food and fiber continue to increase. Population growth in the developing countries peaked at 2. 4 percent a year in 1965, and has fallen to about 2. 1 percent. However, in many developing countries almost half the people are under 15 years of age, poised to enter their productive and reproductive years. The challenges to produce enough food for this growing population will remain great. Even more challenging is growing the food in the areas of greatest need. Presently the world has great surpluses of food and fiber in some areas while there are devastating deficiencies in other areas. Economic conditions and the lack of suitable infrastructure for distribution all too often limit the alleviation of hunger even when there are adequate supplies, sometimes even within the country itself. World hunger can only be solved in the long run by increasing crop production in the areas where the population is growing most rapidly. This will require increased efforts of both the developed and developing countries. Much of the technology that is so successful for crop production in the developed countries cannot be utilized directly in the developing countries. Many of the principles, however, can and must be adapted to the conditions, both physical and economic, of the developing countries.

This is the second of the set of three volumes in the Encyclopedia of Plant Physiology, New Series, that will cover the area of the hormonal regulation of plant growth and development. The overall plan for the set assumes that this area of plant physiology is sufficiently mature for a review of current knowl edge to be organized in terms of unifying principles and processes. Reviews in the past have generally treated each class of hormone individually, but this set of volumes is subdivided according to the properties common to all classes. Such an organization permits the examination of the hypothesis that differing classes of hormones, acting according to common principles, are determinants of processes and phases in plant development. Also in keeping with this theme, a plant hormone is defined as a compound with the properties held in common by the native members of the recognized classes of hormone. Current knowledge of the hormonal regulation of plant development is grouped so that the three volumes consider advancing levels of organizational complexity, viz: molecular and subcellular; cells, tissues, organs, and the plant as an organized whole; and the plant in relation to its environment."

In Recognition of the Forgotten Generation D. L. MULCAHyl Pollen was long believed to serve primarily a single function, that of delivering male gametes to the egge A secondary and generally overlooked value of pollen is that it serves to block the transmission of many defective alleles and gene combinations into the next generation. This latter function comes about simply because pollen tubes carrying defective haploid genotypes frequently fail to complete growth through the entire length of the style. However, the beneficial consequences of this pollen selection are diluted by the fact that the same deleterious genotypes are often transmitted through the egg at strictly mendelian frequencies (Khush, 1973). Gene expression in the pollen might thus at least appear to be a phenomenon of trivial consequence. Indeed, Heslop-Harrison (1979) rightly termed the gametophytic portion of the angiosperm life cycle, the "forgotten generation." This neglect, however, came about despite subtle but constant indications that pollen is the site of intense gene activity and selection. For example, Mok and Peloquin (1975) demonstrated that relatively heterozygous diploid pollen shows heterotic characteristics whereas relatively homozygous diploid pOllen does not. This was proof positive that genes are expressed (that is, transcribed and translated) in the pollen. 1 Department of Botany, University of Massachusetts Amherst, MA 01003, USA viii However, the implications for pollen biology of even this recent and well known study were not widely recognized.

This book has a similar subject content to the author's previous Flow in Wood but with substantial updating due to the abundance of research in the wood science field since 1971. Several different concepts have been introduced, particularly in regard to wood-moisture relation ships. The role of water potential in the equilibria between wood and its humid and moist environments is considered. Two theories are introduced to explain the nonisothermal transport of bound water in the steady and unsteady states. As in the former text, the wood-. structure relationship is emphasized . . The author is especially grateful to Dr. C. Skaar for his careful and critical review of much of the manuscript and for the productive dis cussions of many of the concepts. Dr. T. E. Timell, the series editor, rendered major assistance in the preparation of Chap. 2 and in his editing of the manuscript. The author wishes to thank Dr. W. A. Cote, Mr. A. C. Day, and Mr. J. J. McKeon for providing electron micro graphs, Mr. G. A. Snyder for his photography of much of the art work, Dr. C. H. de Zeeuw for his advice in the field of wood anatomy, and Ms. Mary M. Siau for her careful rendition of the art work. Apprecia tion is extended to Miss Judy A. Barton and Mrs. Stephanie V. Micale for their work in typing and checking the manuscript. Mr. J. A."

Plants, fungi, and viruses were among the first biological objects studied with an electron microscope. One of the two first instruments built by Siemens was used by Helmut Ruska, a brother of Ernst Ruska, the pioneer in constructing electron microscopes. H. Ruska published numerous papers on different biological objects in 1939. In one of these, the pictures by G. A. Kausche, E. Pfankuch, and H. Ruska of tobacco mosaic virus opened a new age in microscopy. The main problem was then as it still is today, to obtain an appropriate preparation of the specimen for observation in the electron microscope. Beam damage and specimen thickness were the first obstacles to be met. L. Marton in Brussels not only built his own instrument, but also made considerable progress in specimen preparation by introducing the impregnation of samples with heavy metals to obtain useful contrast. His pictures of the bird nest orchid root impregnated with osmium were revolutionary when published in 1934. It is not the place here to recall the different techniques which were developed in the subsequent years to attain the modern knowledge on the fine structure of plant cells and of different plant pathogens. The tremendous progress obtained with tobacco mosaic virus is reflected in the chapter by M. Wurtz on the fine structure of viruses in this Volume. New cytochemical and immunological techniques considerably surpass the morphological information obtained from the pathogens, especially at the host-parasite interface.

These are indeed exciting times to be a microbiologist. With one of the buzzwords of the past decade-"Biodiversity," and microbes are reveling in the attention as they represent by far most of the biodiversity on Earth. Microbes can thrive in almost any environment where there is an exploitable energy source, and, as a result, the possible existence of microbial life elsewhere in the solar system has stimulated the imaginations of many. Extremophiles have taken center stage in these investigations, and thermophiles have taken on the lead roles. Consequently, in the past decade there has been a surge of interest and research in the Ecology, Biology, and Biotechnology of microorganisms from thermal environments. Many of the foundations of thermophile research were laid in Yellowstone National Park, primarily by the research of Professor Thomas Brock's laboratory in the late 1960s and early 1970s. The upper temperature for life was debated, the first thermophilic archeum discovered (although it was only later shown to be an archeum by ribosomal cataloging), and the extremes of light, temperature, pH on the physiology of microorga nisms were explored. Interest in thermophiles increased steadily in the 1970s, and with the discovery of deep-sea hydrothermal vents in 1977, thermophilic research began its expo nential explosion. The development of Taq polymerase in the polymerase chain reaction (peR) focused interest on the biotechnological potential of thermophilic microorganisms and on the thermal features in Yellowstone National Park.

Wheat provides over 20% of the calories for the world population of 5. 3 billion persons. It is widely grown in five of the six continents. It is a highly versatile food product in that it can be stored safely for long periods of time and transported in bulk over long distances. In relative terms, it is reasonably priced; over the past quarter century, the inflation-adjusted price of wheat has been declining. Modern milling and baking technology required for the transformation of wheat grain into consumable baked products is available or accessible in all countries of the world. For these reasons, and because Canada is one of world's leading wheat producing countries, it seemed appropriate to include a major symposium on wheat in the scientific and technical program of the 8th World Congress of Food Science and Technology held in Toronto, Canada during September 29-0ctober 4, 1992. In selecting the topics for the symposium on wheat, we attempted to cover a full range of subjects including economics and marketing, nutrition, grading, processing, constituent chemistry and functionality, biote- nology, and safety of genetically modified wheat varieties. The major focus was on common hard (bread) wheats; separate papers were devoted to the unique characteristics and technological properties of common soft (biscuit) and durum (pasta) wheats. Each paper was presented by an acknowledged international expert. This book provides a more permanent record of the papers presented at the symposium.

This book is directed at foresters who work, or have an interest, in the developing world, and at development analysts and theorists who are concerned with the forestry sector. Most readers will be aware that in recent years, some fundamental changes in thinking about the development process in very poor countries have occurred. At one level, the underdevelopment problem has been explained as a lack of absorptive capacity, or implementation ability in very poor countries. However, it now seems that these are only symptoms of a more profound ailment in the whole economic structural and philosophical approach to development. The idea that poor countries could transform their economies through an accelerated process of industrialisation has proved largely incorrect, or at least highly premature. Within the rural sector, emphasis on productivity and aggregate income growth have been shown to have had little effect or, worse still, negative effects, on the burgeoning group of poor and landless rural dwellers.

Soil is formed from physical and chemical weathering of rocks - processes described historically because they involve eons of time-by glaciation and by wind and water transport of soil materials, later deposited in deltas and loessial planes. Soil undergoes further transformations over time and provides a habitat for biological life and a base for the development of civilizations. Soil is dynamic -always changing as a result of the forces of nature and particularly by human influences. The soil has been studied as long as history has been documented. Numerous references to soil are found in historical writings such as Aristotle (384-322 B. c. ), Theophrastus (372-286 B. c. ), Cato the Elder (234-149 B. C. ) and Varro (116-27 B. c. ). Some of the earliest historical references have to do with erosional forces of wind and water. The study of soils today has taken on increased importance because a rapidly expanding population is placing demands on the soil never before experienced. This has led to an increase in land degradation and desertification. Desertifica tion is largely synonymous with land degradation but in an arid land context. Deterioration of soil resources is largely human induced. Poverty, ignorance, and greed are the indirect causes of desertification. The direct cause is mismanage ment of the land by practices such as overgrazing, tree removal, improper tillage, poorly designed and managed water distribution systems, and overexploitation."

Behavioural Mechanisms of Food Selection examines animals belonging to diverse trophic groups, from carnivores, herbivores, micro-algal grazers, to filter-feeders and detritus-feeders. In the past Optimal Foraging Theory has been applied to all these groups, but in different ways and in disci plines that rarely overlap. Here concepts and developments hitherto scattered in the literature are drawn together. This uniquely broad synthesis captures the state of the art in the study of diet selection and prescribes new objectives in theoretical development and research.

This book brings together research into the process of stream acidification and its impact on Welsh surface waters, carried out over the past decade or so. It is perhaps surprising that not until the 1980's was clear evidence of stream acidification assembled. In Wales, concerns over pollution had focused water quality sampling principally on the areas of traditional heavy industry and large urban popula tions served by inadequate sewerage systems and sewage disposal arrange ments. Mistakenly, it had been assumed that, with its prevailing westerly winds, Wales would receive precipitation substantially unpolluted by the industrial and urban emissions from Britain and mainland Europe. Assurance of the high quality of Welsh upland streams, the traditional nursery ground of salmonids, was eroded particularly by studies in the vicinity of Llyn Brianne reservoir in the catchment of the River Tywi of Central Wales. These demonstrated a clear correspondence between the biological quality and fisheries of streams in the catchment and aspects of stream chemistry, par ticularly pH, aluminium and calcium on the one hand, and catchment land use on the other. It is salutary to record that the first signals were of an inexplicable failure of the runs of migratory salmonids into the upper catchment, occupied by the Llyn Brianne reservoir and its influent streams, and the failure to restore the fishery by re-stocking with eggs and fry. Only then did the significance of the recent decline in some other upland lake and reservoir fisheries in Wales become apparent.

Roger C. Dahlman Environmental Sciences Division U.S. Department of Energy Washington, D.C. The potential for humans to alter Earth's atmosphere has been recognized since the end of the 19th century when Arrhenius estimated that a doubling of atmospheric carbon dioxide could alter the atmospheric radiation balance and raise average global temperature. Today, atmospheric CO concentrations play an important part in the 2 climate-change debate. Sources and sinks of CO associated with land use can be 2 significant determinants of the rate and magnitude of atmospheric CO change. 2 Combustion of fossil fuels and the deforestation associated with land-use change both contribute CO to the atmosphere; in contrast, biological processes on land create 2 potential sinks for the excess CO . Thus, land-use change and associated biological 2 processes become important elements in assessments of future atmospheric CO 2 increase; land-cover properties also affect the Earth's albedo, which is a climate feedback.

change is simply described by the rate of income and rate of loss. Our home's energy budget, our firm's inventory, our nation's debt, and humanity's numbers all have accounts that change at rates that are equal to the inputs minus the outputs. Jenny's "system view" of the soil was carried into the fertile fields of Midwestern American prairies from the laboratories of Switzerland in the late 1920s. Jenny's rate equations provided the other paradigm or world view that, I recall, brought us to the threshold of systems ecology as it later evolved in the second half of the twentieth century. As if world renown in the specialties of pedology and soil chemistry were not enough for one lifetime, excerpts below remind us that Hans Jenny has also been a perceptive outdoor field ecologist since his early Alpine expeditions with Braun Blanquet in the mid 1920s. Jenny's ecosystem studies in the pygmy forest, a further classic example of a soil-plant system "run down" over hundreds of thousands of years since its origin, continue to occupy some of the vigorous retirement time near his farm in Mendocino County. But each specific, quantitative case study, and each research area conserved (with additional hard work) for further study by future generations, fits into Jenny's coherent world view. It is that view, and its legacies of discovery and of tangible landscape preserves, which we are privileged to share with their originator in this volume."

In continuation of Volumes 8, 9, and 22 on in vitro manipulation of plant protplasts, this new volume deals with the regeneration of plants from protoplasts and genetic transformation in various species of Actinidia, Amoracia, Beta, Brassica, Cicer, Citrus, Cucumis, Duboisia, Fragaria, Glycine, Ipomoea, Lactuca, Lotus, Lycopersicon, Manihot, Medicago, Nicotiana, Petunia, Phaseolus, Pisum, Prunus, Psophocarpus, Saccharum, Solanum, Sorghum, Stylosanthes, and Vitis. These studies reflect the far-reaching implications of protoplast technology in genetic engineering of plants. They are of special interest to researchers in the field of plant tissue culture, molecular biology, genetic engineering, and plant breeding.

Geoffrey R. Dolby, PhD One of the principal characteristics of a scientific theory is that it be falsifiable. It must contain predictions about the real world which can be put to experimental test. Another very important characteristic of a good theory is that it should take full cognisance of the literature of the discipline in which it is embedded, and that it should be able to explain, at least as well as its competitors, those experimental results which workers in the discipline accept without dispute. Readers of John Parks' book will be left in no doubt that his theory of the feed ing and growth of animals meets both of the above criteria. The author's knowl edge of the literature of animal science and the seriousness of his attempt to incor porate the results of much previous work into the framework of the present theory result in a rich and imaginative integration of diverse material concerned with the growth and feeding of animals through time, a theory which is made more precise through the judicious use of mathematics. The presentation is such that the key concepts are introduced gradually and readers not accustomed to a mathematical treatment will find that they can appreciate the ideas without undue trauma. The key concepts are clearly illustrated by means of a generous set of figures. The crux of the theory comprises three differential Eqs. (7. 1-7."

At last geochemists are offered one comprehensive reference book which gives the Eh-pH diagrams for 75 elements found in the earth's surface environment, including transuranic and other radioactive species. For each of these newly calculated diagrams short explanatory texts are added. For the first time the primary elements are considered in water with metal, sulfur, carbon, and other species as appropriate. Furthermore, based on these figures and up-to-date thermodynamic data presented in this reference, researchers can predict the behavior of elements in the surface environment. Geoscientists, chemists and environmental agencies will also benefit from several brief texts on the importance of various elements to problems of radioactive waste disposal.