Phosphorus (P) is an essential macronutrient for plant growth. It is as phosphate that plants take up P from the soil solution. Since little phosphate is available to plants in most soils, plants have evolved a range of mechanisms to acquire and use P efficiently - including the development of symbiotic relationships that help them access sources of phosphorus beyond the plant's own range. At the same time, in agricultural systems, applications of inorganic phosphate fertilizers aimed at overcoming phosphate limitation are unsustainable and can cause pollution. This latest volume in Springer's Plant Ecophysiology series takes an in-depth look at these diverse plant-phosphorus interactions in natural and agricultural environments, presenting a series of critical reviews on the current status of research. In particular, the book presents a wealth of information on the genetic and phenotypic variation in natural plant ecosystems adapted to low P availability, which could be of particular relevance to developing new crop varieties with enhanced abilities to grow under P-limiting conditions. The book provides a valuable reference material for graduates and research scientists working in the field of plant-phosphorus interactions, as well as for those working in plant breeding and sustainable agricultural development.

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, systematics, ecology, and vegetation science.

Nearly twenty years have passed since the publishing of a broadly-based texthook on hiolog ical control (Huffaker and Messinger 1976). In the interim, other works on biological control have been either briefer treatments (DeBach and Rosen 1991), or collections of essays on selected topics (Waage and Greathead 1986; Mackauer and Ehler 1990). Our text has been written to fill what we believe is a need for a well-integrated, broadly-based text of appropriate length and degree of technical detail for teaching a one semester upper level course in hiological control. We have attempted to focus on principles and concepts, rather than on biological control of particular taxa or hiological control by particular kinds of natural enemies. Therefore, for example, the reader will find the material on biological control of weeds integrated with biological control of insects and mites into chapters on principles, techniques, and applications rather than presented separately. Only biological control of plant pathogens is addressed independently, an appraoch made necessary by the many special features and concepts in plant pathogen biological control."

Sulfur is one of the most versatile elements in life. This book provides, for the first time, in-depth and integrated coverage of the functions of sulfur in phototrophic organisms including bacteria, plants and algae. It bridges gaps between biochemistry and cellular biology of sulfur in these organisms, and of biology and environments dominated by them. The book therefore provides a comprehensive overview of plant sulfur relations from genome to environment.

This book provides an excellent illustration of the interrelationship between progress in scientific methodology and conceptual advances, and its publica tion should contribute to further advances. It is well known that major advances in understanding often follow the development of new methods. The development of the acetylene reduction assay for nitrogenase activity provides a good example of this interrelationship between theory and methods. Theoretical knowledge led to a search for substrates for nitro genase that could be assayed for more easily than ammonium, the normal product of the enzyme. The discovery of the reduction of acetylene to ethylene by nitrogenase provided the ideal answer to the problem by provid ing a rapid, specific, nondestructive, and inexpensive assay for nitrogenase activity. This assay is now used by almost every laboratory doing research on nitrogen fixation. However, further use and development of the acetylene reduction assay has shown that it can underestimate nitrogenase activity and can even give incorrect relative values under some circumstances. The major problem is that exposure of legume nodules to acetylene can cause a large increase in the resistance to oxygen diffusion into the nodule. This reduced supply of oxygen decreases the rate of nitrogenase activity within a few minutes."

Rinie Hofstra has been a member of the Department of Plant Physiology, University of Groningen, the Netherlands, for 24 years. The nearer we came to 31 March 1985, her 65th birthday, the more we all realized how we would miss her - not only scientifically, but also socially. She left her mark on both research and teaching, always with an open mind and willing to change. After her PhD Thesis on 'Nitrogen Metabolism in Tomato Plants' she first continued working in that field, but soon started a joint project with the Department of Plant Ecology on hemiparasites. She then became involved in carbon metabolism, which resulted in her giving a Biotrop Course on C /C metabolism in 3 4 Indonesia. Her own research group, originally working on 'Nitrogen Metabolism', soon embraced 'Energy and Nitrogen Metabolism', as the research on respiration became more and more important. In running her group she showed all sides of her person. She used to stimulate and encourage everyone around her and to integrate the various lines of research. At the same time she always had an open mind for the opinion of all members of her group. And together they regularly criticized and evaluated the various projects and decided how to continue.

The Annual Beltsville Symposium provides a forum for interaction among scientists involved in research that is vitally important to agri culture and to the agricultural sciences. The Twelfth Symposium in this series focused on the unifying biochemical and physiological mechan isms controlling growth and development of biological systems - ani mals, plants insects. Unraveling the complex biochemical mechanisms associated with the sequencing of organism growth and development and identifying, locating, and manipulating key control mechanisms are essential in utilizing the full potential of biotechnology for improving the composition and quality of agricultural products and the profitability of agriculture. Accordingly, speakers directed their remarks to basic aspects of biological mechanisms in their area of specialization with considera tion given to current status, future direction, potential impact, and limitations to progress. The Symposium addressed fundamental questions in: -Tissue specific gene regulation: cell division and differentiation -Mechanisms for regulating hormone concentration -Hormonal regulation of growth and development -Non-hormonal regulation of growth and development -Nutritional regulation of growth and development Because the backgrounds of the symposium attendees covered a wide spectrum in the basic biological and physical sciences, each topic was introduced by a brief overview, but general reviews were avoided in favor of findings from on-going research projects. The symposium brought together a distinguished group of invited scientists from around the world who are leaders. Many attendees made poster presentations which increased the exchange of ideas and sti mulated informal discussion."

Studies on the phenomenon of plant pathogenesis (disease development) have been useful to have a deep insight into the interactions between host plant and the pathogen. Depending on the levels of susceptibility (compatibility) or resistance (incompatibility) of the host plant and virulence of the pathogen, disease development may progress, either leading to symptom expression or result in the suppression of pathogen proliferation. Molecular techniques have been applied to elucidate the nature of interactions between the gene products of the plant and pathogen at cellular and molecular levels. Successful evasion of host's surveillance system and subsequent activities of metabolites of the pathogen (enzymes and toxins) encoded by pathogen genes counteracting the effects of various defense-related antimicrobial compounds present already or produced by the host plants, after initiation of infection have been critically studied by applying various molecular techniques. In addition to studying various phases of disease development in individual plants, molecular methods have been demonstrated to be effective, in gathering data on various aspects of epidemiology under natural conditions where the interaction of pathogen with populations of plants is influenced significantly by the environmental conditions existing in different ecosystems. This volume focuses on the possibility of applying the knowledge on pathogenesis and molecular epidemiology to determine the vulnerable stages in the life cycles of the pathogens that can be disrupted to achieve more effective disease control.

This book summarizes the experimental work conducted during a trans-disciplinary research program conducted for six years by the German Research Foundation. Each chapter includes introductory remarks written by internationally recognized scientists in their research areas.

Contributiing authors representing outstanding German scientists from such different disciplines as Physics, Biochemistry, Plant Nutrition, Botany, and Molecular Biology not only report original research but also review the state of knowledge in their fields of research.

The importance of mycorrhiza for the improvement of plant growth is increasingly being realised in Agriculture and Forestry and several mycorrhizal fungi have been commercially recognised for the purpose. The aim of this book is to describe the various techniques used to study the mycorrhizal biology. Problems with preparing such a book are many. Mainly mailing of manuscripts to and from authors resulted in irregular and final editing. Every effort was made not to change the peer review original manuscript to ensure accuracy. Our sole aims is to communicate to the greatest extent possible a current world need in mycorrhizal research. Plant productivity is regulated by microbial associations established in the plant root systems. The interactions of microorganisms and plant roots are especially important in providing nutritional requirements of the plant and the associated microorganisms. Plant growth and development are controlled largely by the soil environment in the root region -rhizosphere. This is a very complex environment in which the effects of the plant on soil microorganisms and the effects of microorganisms on the plant are interacting, interdependent and highly complex. Plant root exudates and breakdown products feed the microbes and the microbe in tum often benefit the plant. Mycorrhizal fungi are important tools for increasing growth, development and yield of economically important plants, they play important role of biofertilizer which can help establish plants in nutrient deficient soils, particularly phosphorus deficient soils, arid, semi-arid and waste lands.

As drought tolerance is a multidirnensional stress, drought tolerance study is a multidisciplinary adventure. In 1992, the network INTERDROUGHT was created with the objective of joining the scientists of the different fields of research involved in drought tolerance study. The network was funded by the EEC and gathered 25 European teams specialized in molecular biology, physiology and geneties. 1\vo workshops were successively organized in 1993 in Sitges (Spain) and in 1994 in Ischia (Italy). After those two European workshops, the necessity of opening the network to the whole scientific community was already clear, and in 1995 the first INTERDROUGHT international conference was held in Montpellier (France). During this meeting, eleven speakers were invited to present a review in their field of research, in a way accessible to all researchers and students, especially those who are not familiar wlth one of the three fields of interest. These eleven reviews are presented in this book. From these reviews three major difficulties arose for drought tolerance irnprovement: - the definition of the drought stress that plants experience; -the differentiation between non adaptive and adaptive response to drought stress; -the identification of the adaptive responses that improved drought yield without decreasing significantly the potential yield. The use of integrated strategies of research will certainly provide irnportant results, such as the recent data obtained on molecular and physiologieal analysis of Arabidopsis mutants.

The sixth International Symposium on Genetics and Molecular Biology of Plant Nutriti9n was held in Elsinore, Denmark from August 17-21, 1998 and organised by th RiS0 National Laboratory in the year of its 40 anniversary. The 98 participants represented 23 countries and 80 scientific contributions with 43 oral and 37 poster presentations. The symposium addressed the molecular mechanisms, physiology and genetic regulation of plant nutrition. The Symposium brought together scientists from a range of different disciplines to exchange information and ideas on the molecular biology of mineral nutrition of plants. The symposium emphasised: * Bridging the gab between molecular biology, applied genetics, plant nutrition and plant breeding. * The development of methodologies to improve the efficiency and effectiveness of nutrition of plants * Quality of plant products. With sessions on: Nitrogen; Phosphorous; Micronutrients; Symbiosis; Membranes; Stress; Heavy Metals and Plant Breeding. In comparison with the previous conferences in this series more emphasis was placed on use of molecular techniques to clarify physiological mechanisms and processes, gene expression and regulation, as well as genetic marker assisted analysis. Significant of molecular genetic markers and other progress was reported in exploitation biotechnologies in breeding programmes.

Bioactive Carbohydrate Polymers is probably the first book dealing with the latest in the field of polysaccharides and related products and their biological activities, especially the immunological effects. The different chapters describe the structure and bioactivity of polysaccharides from plants used in traditional medicine in different parts of the world, especially China, Japan and Europe. The focus of the book is on immunologically active plant and seaweed polysaccharides, pharmacological activities of sulphated polysaccharides of animal and seaweed origin, and on possible activities of polysaccharides in our food. Methods for isolation and characterisation of the polymers with chemical and enzymatic methods is covered, as well as discussions on the different biological test-systems and the information they provide. This book will be useful to scientists and postgraduate students working with polysaccharides and their possible uses, and should be of interest for people working in the areas of chemistry, biology, pharmacy and medicine.

Increased atmospheric nitrogen deposition and changes in the management of heathlands have caused a significant change in the species composition of the NW-European heathlands. This change from ericaceous towards gramineous dominance is analysed in detail in Heathlands: Patterns and Processes in a Changing Environment. Special emphasis is put on the effects of increased atmospheric nutrient input on nutrient cycling, competition between plant species and plant--herbivore interactions. The possibilities for the long-term conservation of heathlands are discussed by considering regeneration from seed and the usefulness of mathematical management models. The book provides a synthesis of pure and applied plant ecology. It is vital reading for plant ecologists, biological conservationists, heathland managers and government decision makers.

The present book provides a comprehensive overview of our current knowledge on plastid biogenesis, plastid-nuclear communication, and the regulation of plastid gene expression at all levels. It also assesses the state-of-the-art in key technologies, such as proteomics and chloroplast transformation. Written by recognized experts in the field, the book further covers crucial post-translational processes in plastid biogenesis and function, including protein processing.

Our image of plants is changing dramatically away from passive entities merely subject to environmental forces and organisms that are designed solely for the accumulation of photosynthate. Plants are revealing themselves to be dynamic and highly sensitive organisms that actively and competitively forage for limited resources, both above and below ground, organisms that accurately gauge their circumstances, use sophisticated cost-benefit analysis, and take clear actions to mitigate and control diverse environmental threats. Moreover, plants are also capable of complex recognition of self and non-self and are territorial in behavior. They are as sophisticated in behavior as animals but their potential has been masked because it operates on time scales many orders of magnitude less than those of animals. Plants are sessile organisms. As such, the only alternative to a rapidly changing environment is rapid adaptation. This book will focus on all these new and exciting aspects of plant biology.

Plants are unique as their development and morphogenesis are plastic throughout their lives. They continuously monitor diverse biotic and abiotic parameters of their environment and these sensory perceptions shape their organs and bodies. Although genes are critical, the final form and architecture of above-ground organs, and es- cially of root systems, are determined by their sensory activities associated with motoric responses (Friml 2003; Hodge 2009). Sensory plant biology and plant el- trophysiology were two lively disciplines until the late 1970s (Bunning 1959; Haupt and Feinleib 1979) but then, for somewhat obscure reasons, they showed no further development. In the last few years, however, there have been numerous advances in plant sciences. These necessitate not just a revival of plant electrophysiology and sensory biology, but also the introduction of plant neurobiology, which includes also plant sensory ecology (Balu ka et al. 2006a; Brenner et al. 2006). First of all, and contrary to all "mechanistic" predictions based on the high turgor pressure of plant cells, endocytosis has been found to be an essential process of plant cells which impinges upon almost all aspects of plant life ( amaj et al. 2005, 2006). Moreover, recent advances in plant molecular biology have identified, besides classic n- rotransmitters, also several proteins typical of animal neuronal systems, such as acetylcholine esterases, glutamate receptors, GABA receptors, and endocannabinoid signaling components, as well as indicating signaling roles for ATP, NO, and re- tive oxygen species (Balu ka et al. 2006b)."

The 18 chapters making up In Vitro Haploid Production in Higher Plants are divided into two sections. Section 1 (eight chapters) covers historical and fundamental aspects of haploidy in crop improvement. Section 2 deals with methods of haploid production, including anther culture, micropore culture, ovary culture, pollination with irradiated pollen, in vitro pollination, and special culture techniques, including polyhaploid production in the Triticeae by sexual hybridization, the influence of ethylene and gelling agents on anther culture, conditional lethal markers, and methods of chromosome doubling.

This volume contains a selection of 14 articles dealing with different aspects of biomonitoring and their relation to questions of global change. During the last 10 - 15 years, vegetation changes due to various causes have been more intensively studied in biological and environmental sciences. Especially aspects of global warming lead to a great variety of tasks for vegetation science (see e.g. the articles by Grabherr, Gottfried & Pauli; Carraro, Gianoni, Mossi, KlOtzli & Walther; Walther; Defila; Stampfli & Zeiter; Rothlisberger; Burga & Perret and Moller, WUthrich & Thannheiser). The different aspects of applied biomonitoring related to (possible) environmental changes concern various ecosystems, e.g. Central European beechwoods, Insubrian evergreen broad-leaved forests, thermophilous lowland deciduous forests, dry grasslands of the lower montane belt of the Ticino Alps, alpine mountain peaks of Switzerland and Austria, Swiss alpine timberline ecotones, and high arctic tundra vegetation. The volume is divided into three parts: A. General aspects of biomonitoring (contributions by KlOtzli; Wildi and Labasch & Otte) , B. Examples of applied biomonitoring in Germany and Switzerland (articles by Hakes; Herpin, Siewers, Kreimes & Markert; Defila; Stampfli & Zeiter; Rothlisberger and Ruoss, Burga & Eschmann), and C. Aspects of global change in the Alps and in the high arctic tundra (Grabherr, Gottfried & Pauli; Burga & Perret; Carraro, Gianoni, Mossi, KlOtzli & Walther; Walther and Moller, WUthrich & Thannheiser).

Since the beginning of agricultural production, there has been a continuous effort to grow more and better quality food to feed ever increasing popula tions. Both improved cultural practices and improved crop plants have allowed us to divert more human resources to non-agricultural activities while still increasing agricultural production. Malthusian population predictions continue to alarm agricultural researchers, especially plant breeders, to seek new technologies that will continue to allow us to produce more and better food by fewer people on less land. Both improvement of existing cultivars and development of new high-yielding cultivars are common goals for breeders of all crops. In vitro haploid production is among the new technologies that show great promise toward the goal of increasing crop yields by making similar germplasm available for many crops that was used to implement one of the greatest plant breeding success stories of this century, i. e., the development of hybrid maize by crosses of inbred lines. One of the main applications of anther culture has been to produce diploid homozygous pure lines in a single generation, thus saving many generations of backcrossing to reach homozygosity by traditional means or in crops where self-pollination is not possible. Because doubled haploids are equivalent to inbred lines, their value has been appreciated by plant breeders for decades. The search for natural haploids and methods to induce them has been ongoing since the beginning of the 20th century."

Af ter a kind mo ti va tion by Judit Si mon (Ed i tor-in-Chief of the Jour nal of Ther mal Anal y s is and Cal o ri m e t r y , Kluwe r Ac a dem ic Pub lis her) and ne go ti a tions with po- si ble con tri bu tors - lasting for m ore than one year - it was de cided to write a book about the ap pli ca tion of ther mal meth ods in bi ol ogy. Its aim was to be a guide how to per form ex per i ments and what kind of in for mation m ight be gained by them. We tried to col lect in for mation tha t could be achieved only dur ing a long per sonal pra- tice. In this way sci en tists from bi ol ogy and med i cine , e. g. , who are not so skilled in phys ics and math e mat ics may re al ize very soon the beauty and power of this tool at one hand. On the other hand, those sci en tists with better back ground in nat u ral sc- ences can be more sensitive to find out exciting biological problems.

A state-of-the-art overview of the intricate functional virus/host relationships that allow a virus or viroid to move cell-to-cell and systemically through the plant, as well as from plant to plant, and, thus, to spread infection. The book also illustrates the mechanisms by which viruses overcome plant defence responses, such as RNA silencing. Arabidopsis is used as an illustration of a plant host eminently suitable for genetic approaches to identify novel players in plant/virus interactions.

Since the beginning of agricultural production, there has been a continuous effort to grow more and better quality food to feed ever increasing popula tions. Both improved cultural practices and improved crop plants have allowed us to divert more human resources to non-agricultural activities while still increasing agricultural production. Malthusian population predictions continue to alarm agricultural researchers, especially plant breeders, to seek new technologies that will continue to allow us to produce more and better food by fewer people on less land. Both improvement of existing cultivars and development of new high-yielding cultivars are common goals for breeders of all crops. In vitro haploid production is among the new technologies that show great promise toward the goal of increasing crop yields by making similar germplasm available for many crops that was used to implement one of the greatest plant breeding success stories of this century, i. e., the development of hybrid maize by crosses of inbred lines. One of the main applications of anther culture has been to produce diploid homozygous pure lines in a single generation, thus saving many generations of backcrossing to reach homozygosity by traditional means or in crops where self-pollination is not possible. Because doubled haploids are equivalent to inbred lines, their value has been appreciated by plant breeders for decades. The search for natural haploids and methods to induce them has been ongoing since the beginning of the 20th century."

Nitrogen is an essential element for plant growth. During the green revolution nitrogenfertilisation was responsible for spectacular yield increases. At present yield is balanced with commitments towards the environment and sustainable agriculture. For agro-biotechnology comprehensive knowledge of plant functioning is needed. Yield improvement and accumulation of essential nitrogen compounds is relying on selection and gene technologies.

Research on the uptake, acquisition and assimilation of nitrogen, as well as the synthesis and storage of reserve and defence N-compounds, therefore, is essential. The third volume in the Plant Ecophysiology series integrates functional and molecular physiology with ecophysiological and sustainable agricultural approaches to get a better understanding of the regulation and the impact of environmental and stress signals on nitrogen acquisition and assimilation. The book is of interest for advanced students and junior researchers and supplies comprehensive information for scientists working in the field of nitrogen metabolism and readers interested in sustainable development.

The beginnings of human civili zation can be traced back to the time , ne- ly 12 ,000 years ago , when th e early humans gradually ch anged from a life of hunting and gathering food , to producing food. This beginning of pri- tive agriculture ensured a dependable supply of food , and fostered the living together of people in groups and the development of s o c i e ty. During th is time, plant s e e ds were recognized a s a valuable s o ur c e of food and nutrition , and began to be used for growing plants for food. Ever s i n c e , plant seeds have played an important role in the development of the human civilization . Even today, s e e ds of a few crop s p e c i e s , s uc h as the cereals and legume s, are the primary s o u r c e of most human food , and the predominant commodity in international agriculture. Owing to their great importance as food for human s and in international trade , seeds have been a favorite object of s t u d y by developmental biologists and physiologi sts , nutritionist s and chem i sts . A wealth of useful information i s available on th e biology of seed s .