Forest decline became a matter of public and scientific concern in France in 1983 when conifers in the Vosges mountains were found to exhibit unusual crown deterioration. An impassioned controversy on a supposedly large scale forest health problem was then in full swing in Central Europe. A co-ordinated research programme entitled DEFORPA ("Deperissement des For ts et Pollution AtmospMrique") was launched in 1984. This programme ran from 1984 to 1991 and a number of projects are still in progress. The Programme was sponsored by three French ministries (Enviroument, Agriculture and Forestry, Research and Technologyl), several state agencies, various regional authorities and the Commission of the European Communities (DO xn and DG VI). Initially, emphasis was solely laid on the understanding of forest decline in the mountainous areas - because damage was most obvious there - in relation to natural and man-made factors. Air pollution was given high but not overwhelming priority. Thus, the DEFORPA Programme was not in its essence a nation-wide assessment of air pollution effects, unlike a number of national acidification research programmes in Europe and North America. During. the programme, however, the areas of concern expanded. In particular, research into water acidification in the Vosges mountains was developed in parallel with the DEFORPA Programme, and possible eutrophication of the ground flora in northeastern France became the subject of new research.

An increase in the demand for wood results in improved recovery and less residual biomass in the forests. Paradoxically, interest in forest residue as a renewable source of raw material seems to be in a reverse ratio to its availability in a certain area. Finland and Sweden are probably more dependent on forestry and forest in dustries than any other developed countries in the world. A sufficiency of raw ma terial for integrated forest industries is vital for the national economy of both countries, and a great deal of attention is being paid to the long-term potential of unutilized biomass left behind in logging operations. Furthermore, since these countries possess no reserves of fossil fuels, and since their per-capita consump tion of primary energy is exceptionally high, they also consider unmerchantable forest biomass a realistic source of indigenous energy. A joint Nordic research project on harvesting and utilization of logging residue was carried out in 1969-1976 under the auspices of the Nordic Research Council on Forest Operations. This fruitful cooperation soon gave rise to related national projects in Sweden, Finland, Norway, and Denmark, stimulating further research and producing practical applications. Concurrently, particularly after the worldwide energy crisis in 1973, research on all aspects of utilization of forest bio mass mushroomed in the United States, Canada, and the Soviet Union. An ex plosive increase occurred in both the number and diversity of biomass studies.

In a very real sense, much of North American physiological plant ecol ogy began in the Basin and Range and has been researched there over the last four decades. However, we believe that this book may be the first attempt to bring together the full range of contemporary research into the fascinating plant biology of the Basin and Range Province. We have invited contributions from researchers presently working in and around the Province and asked them to review the major vegetation zones and distinctive environmental issues from a predominantly plant ecophysiological perspective. As researchers interested in plant physi ological and ecological processes, and in atmospheric processes affect ing vegetation, we have tended to emphasize the atmosphere, plant, soil continuum in structuring this book. After an introduction to the geography of the region, we deal with atmospheric processes and climates of the Great Basin, follow with chapters on the different vegetational zones, treated from ecophysiological perspectives, and then place emphasis on plant-soil relations. We have not treated plant animal interactions in the detail that the impacts of man and his domesticated animals on the desert ecosystem deserve. However we have included a review of a very promising technique (analysis of stable isotopes at natural abundance) for integration of these processes. We close with a compelling statement of the case for the Great Basin as a laboratory for climatic change research, prepared by a multidisciplinary team from the Desert Research Institute.

Genetic material is in flux: this is one of the most exciting recent concepts in molecular biology. This volume of "Plant Gene Research" describes changes that occur in the genetic material of plants. It is worthwhile re membering that the first examples of unstable genomes were described for maize before DNA was known to be the genetic material. Now trans posable elements like the ones found in maize have been described in almost all organisms and have become incorporated into our thinking about genome structure. Flux in the plant genome is not restricted to transposable elements or to nuclear genes. Exchanges of genetic material have been demonstrated within organelle DNA, between organelle DNAs or between organelle and nuclear DNAs. Such exchanges may only occur over evolutionary times or may be a continuing process. Also the environment alters the plant genome. Stress, either viral, nutri tional or tissue-culture induced causes heritable changes in the genome. Infection with the crown gall bacterium Agrobacterium tumefaciens results in the transfer of bacterial DNA into the plant genome."

I first became interested in the methods of planning the sequence and timing of jobs on large-scale development projects, as a field officer involved in planning and implementing mechanised farming schemes in Uganda in the mid-sixties. This interest was reinforced by experience of agro-industrial projects in both Nigeria and Iran, when it became obvious that the lax traditional methods of both planning and controll ing the implementation of agricultural and other rural development projects were very ineffective compared with those already in use in other disciplines. An extended spell as Resident Adviser on a World Bank project to strengthen planning and project management services in the agricultural sector in Sind Province, Pakistan, stimulated this interest further, and gave opportunities to develop the use of improved methods on some very complex schemes. This book summarises the experience gained in adapting critical path methods, well established in other fields, to Third World development projects, with their peculiar problems. It would not have been possible to reach this point without the help and stimulation of discussions with a large number of colleagues, includ ing John Joyce (then of Hunting Technical Services), Hatsuya Azumi (World Bank), and-particularly-Zaffar Sohrwardy and Akhtar Ali of Aarkays Associates in Karachi, during our work together. My thanks are also due to Yasin Mohammed, who typed most of the original draft; Anwar Mohammed and Irene Mills for final typing; and to my wife, Jill, for drawing the original figures.

Environmental stresses, such as high and low temperature, salinity, and drought, represent limiting factors to agricultural productivity worldwide. Their impact is not only on crops that are presently being cultivated, but they are also significant barriers to the introduction of crop plants into noncultivated areas. The book describes the cellular, biochemical, and molecular mechanisms in plants that regulate tolerance to stresses. Also discussed are prospects of engineering stress-tolerant plants through the modification of germplasm.

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."

Presented here is a comprehensive account of both theoretical and practical aspects of sugarcane production. The first of two parts of the book deals with origin, distribution, soil and climatic requirements, seed bed preparation, cultural and nutrient requirements, fertilization, irrigation, ratooning, weeds, pests, diseases, ripening, and harvest. In thesecond part, energy and fibre cane, cane development, and manufacturing techniques of sugar and by-products are treated in detail. This book will serve as a vademecum for cane growers, sugar and sugarcane technologists, students and teachers.

Herbicides are part of modern agricultural production systems and therefore contribute significantly to the economy of agricultural products. At the same time, herbicides are potent and specific inhibitors of plant metabolism and may therefore be used as valuable tools in basic plant physiological research. A well-known example is the photosynthesis-inhibiting herbicide diuron, known to plant physiologists as DCMU, which has become one of the essentials in modern photosynthesis research. Similarly, knowledge in other areas of plant metabolism may be advanced by the use of herbicides as specific inhibitors. This book describes the effects of herbicides on the metabolism of higher plants from the viewpoint of the plant physiologist. The material of this book is therefore, as far as possible, divided into areas of metabolism. This book intends (1) to present the reader with current knowledge and views in the area of herbicide modes of action and (2) to promote the future use of herbicides as metabolic inhibitors in plant physiological research to the advantage of both, the pesticide and the plant sciences. I wish to express my thanks to my colleagues and friends Prof. N. Amrhein, Prof. E. Elstner, Dr. L. Eue, Dr. J. Konze, Dr. K. Liirssen, Dr. W.Oettmeier, Dr. H. Quader, Dr. R. R. Schmidt, Dr. R. H. Shimabukuro, Dr. J. Stetter, Prof.

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.

Der vorliegende 6. Band konnte die Oberschrift "Pflanzenschutzforschung auf neuen Wegen" tragen. Trotz der verbreiteten, meist aufmangelndem Informations- stand beruhenden Voreingenommenheit gegen den chemischen Pflanzenschutz, nimmt dessen Bedeutung sHindig zu. Das beruht auf der Notwendigkeit einer sicheren und rationellen landwirtschaftlichen Produktionssteigerung, die durch das rapide Wachstum der WeItbevolkerung erzwungen wird. Zwar ist die land- wirtschaftliche Produktivitat auch in einigen Entwicklungslandern wahrend der letzten 15 Jahre merklich gestiegen, sie haIt aber vielfach mit der Vermehrung der Bevolkerung nicht Schritt. Der Pflanzenschutz ist nicht einseitig auf bestimmte Methoden festgelegt, sondern bedient sich unvoreingenommen aller wirtschaftlich und okologisch vertretbaren Wege und Verfahren. Hierbei wird auch die Forschung nach neuen Wirkstoffen und chemischen Verfahren auf sehr breiter Grundlage weiterbetrieben, wenn auch unter merklicher Steigerung der Forschungskosten. Jeder neue Wirk- stoff muB einen Fortschritt gegeniiber einem eingefUhrten Handelsprodukt dar- stellen. Wichtige Kriterien sind hierbei neben der Wirksamkeit die Umwelt- vertraglichkeit, unter anderem giinstigere toxikologische Eigenschaften, Sicher- heit in der Anwendung und Wirtschaftlichkeit. Wie schon in Band 3 (Beitrag Haug) dargestelIt, sind gerade auch diejenigen Kosten fUr Forschung und Ent- wick lung, die der langfristigen Unbedenklichkeit und Sicherheit der Produkte dienen, iiberproportional gestiegen.

The public's attitude toward air pollution in the United States evolved substantially during the 1960s. One of the results of the nation's emerging environmental ethic was the creation of the U. S. Environmental Protection Agency (EPA) in December of 1970. Prior to this time, research was focused on the impacts of air pollution on human health and welfare and was largely conducted by several federal research agencies, which included the Department of Health, Education, and Welfare; the National Oceanic and Atmospheric Administration; and the U. S. Department of Agricul ture. After the creation of the EPA, much of this work was consolidated in one regulatory agency, which resulted in periodic evaluations of the various effects of atmospheric pollution on human health, materials, agriculture, and forest ecosystems. At the same time that environmental interest was growing in the United States, concern increased in the European scientific community and public over the ecological impacts of acidic deposition. As the magnitude of the damage to European lakes and streams and the widespread decline in Norway spruce and silver fir was reported, concern that similar problems were occurring in the United States increased substantially. This concern was heightened by press reports of high elevation spruce-fir forest declines in the Adirondack and Appalachian Mountains and the decline and death of sugar maples in the northeastern United States and Canada.

This is a stimulating tale of the interplay of observation, experimentation, working hypotheses, tentative conclusions, niggling and weightier doubts and great aspirations, on the part of some score of students, on varied ecological and other aspects of the regime and role of fire in relevant biomes and ecosystem- mainly in South Africa - and on other pertinent features of fire ecology. The impressive contents is a tribute to conveners and authors alike. One can expect a profound range and depth ofinvestigation and interpretation, a closeknit fabric of knowledge, delicately interwoven with wisdom, an exposition and quintessence of information. Admipable is the collective vision responsible for selecting appropriate topics: the wide sweeps of the brush picturing the nature of the biomes; ably describing the fire regimes - whether in grassland, savanna, fynbos or forest; skillfully defining the effects of such regimes - according to ecosystem - upon aerial and edaphic factors of the habitat, upon constituent biota, individually, specifically and as a biotic community; elucidating the basic implications in the structure and dynamics of the plant aspect of that community ... and unravelling to some degree the tangled knot of the conservation and dissipation of moisture and nutrients. Moreover, gratitude is owed for efforts exerted to understand the interplay of fire and faunal behaviour and dynamics as well as composition, together with the principle of adaptive responses of organisms of diverse kinds.

The importance of irrigation in the world's agriculture is rapidly increasing. Although it is practised on a large scale mainly in arid and semi-arid zones, supplementary irrigation is becoming popular in semi-humid regions as well. The record of irrigation speaks for itself in terms of increased crop production. However, the question remains as to how permanent the achievement may be. Judging from history, it seems that irrigation eventually failed in many regions because the knowledge and technology available to society at the time were incapable of coping with the problems created. Undoubtedly soil salinity is the most prevalent and widespread problem limiting crop productivity in irrigated agriculture. It has, therefore, attracted the attention of the scientific community since the advent of modern agronomic research. Through the past six to seven decades a considerable body of information has been accumulated, which has promoted the understanding of the principles involved and helped to develop the technology for coping with the problems. Our present knowledge, if judiciously applied, is adequate for coping with many of the salinity problems resulting from mismanagement of irrigation and drainage. But for this knowledge to be used, it has to be generally known and understood and be re-examined from time to time.

Metal Speciation in the Environment is a multidiscipliary treatment of the occurrence, mobility and detection of metal compounds within different environments as well as their interaction with life. Special emphasis is given to the complexation of metals, to the state of the art of trace analytical methodology available for metal speciation (including atomic absorption spectrometry, plasma emission and mass spectrometry, neutron activation analysis, electrochemical methods, chemical sen- soring, a.o.), and environmental chemistry of elements such as the actinides and heavy metals (e.g. chromium, arsenic, tin, and copper).

The information presented in this book is the result of combined research efforts of scientists at the University of Alaska, Fairbanks, the Institute of Northern Forestry, USDA Forest Service, and the Systems Ecology Research Group, San Diego State University. The objective of the volume is to present a synthetic overview of structure and function of taiga forest ecosystems in interior Alaska. The data base for this work has appeared in earlier published articles including the special issue of the Canadian Journal of Forest Research Volume 13:5 (1983). Stimulus for this book was a conference held in Fairbanks from June 10-14, 1983. The papers presented at the conference were fore runners of the chapters in this book. We invited 19 scientists from North America and England to critique our research and synthesis efforts. Six of these people were asked to write introductory chapters for each section of the book. Formal presentation sessions, combined with field trips to research sites, introduced the invitees to the primary and secondary successional ecosystems with which we were dealing. A major wildfire, only 24 km from the University campus, was contained the week prior to the conference and one field trip provided graphic evidence of fire impact in subarctic forests. The conference conveners regretted that it was not possible to host a similar meeting during synthesis efforts in mid-January."

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.

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."

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.

Rhizobia are bacteria which inhabit the roots of plants in the pea family and "fix" atmospheric nitrogen for plant growth. They are thus of enormous economic importance internationally and the subject of intense research interest. Handbook for Rhizobia is a monumental book of practical methods for working with these bacteria and their plant hosts. Topics include the general microbiological properties of rhizobia and their identification, their potential as symbionts, methods for inoculating rhizobia onto plants, and molecular genetics methods for Rhizobium in the laboratory. The book will be invaluable to Rhizobium scientists, soil microbiologists, field and laboratory researchers at agricultural research centers, agronomists, and crop scientists.

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.

Chemistry of Plant Protection continues the handbook "Chemie der Pflanzenschutz- und Schadlingsbekampfungsmittel", edited by R. Wegler. Volumes 4 and 5 of the series provide the first complete and in depth overview of synthetic pyrethroid insecticides . Volume 5 presents a detailed survey of the numerous synthetic methods (270 reaction schemes) and of stereochemical aspects of trade products, and a compilation of almost every patent on pyrethroids (2700 references evaluated).

Second in the series, High-Tech and Micropropagation, this work covers the micropropagation of trees and fruit-bearing plants, such as poplar, birches, larch, American sweetgum, black locust, "Sorbus," sandalwood, "Quercus," cedar, Persian walnut, date palm, cocoa, "Citrus," olive, apple, pear, peach, plum, cherry, papaya, pineapple, kiwi, Japanese persimmon, grapevine, strawberry, and raspberry. The importance and distribution of conventional propagation and in vitro studies on individual species are discussed. In particular detail, the transfer of in vitro plants to the greenhouse or the field, and the prospects of commercial exploitation are examined. The book will be of use to advanced students, research workers and teachers in horticulture, forestry and plant biotechnology in general, and also to individuals interested in industrial micropropagation.

No matter what forests are used for, forest managers have to deal with interactions between individual trees and between trees and other forest organisms. To understand these interactions, long-term monitoring of spontaneous forest development is necessary. A complete monitoring system has been developed including a computer package for analysis of long-term observation of forest dynamics. The system's name, "SILVI-STAR," is an acronym of SILVIgenesis and Single-tree Three-dimensional Architecture. A method of nested plot data collection on forest architecture and plant species composition has been developed out for monitoring purposes.