Allelochemicals play a great role in managed and natural ecosystems. Apart from plant growth, allelochemicals also may influence nutrient dynamics, mycorrhizae, soil chemical characteristics, and microbial ecology. Synergistic action of various factors may better explain plant growth and distribution in natural systems. The book emphasizes the role of allelochemicals in shaping the structure of plant communities in a broader ecological perspective. The book addresses the following questions: (1) How do allelochemicals influence different components of the ecosystem in terms of shaping community structure? (2) Why is it difficult to demonstrate interference by allelochemicals (i.e., allelopathy) in a natural system in its entirety? Despite a large amount of existing literature on allelopathy, why are ecologists still skeptical about the existence of allelopathy in nature? (3) Why are there only scarce data on aquatic ecosystems? (4) What role do allelochemicals play in microbial ecology?.....

Allelochemical interactions, during the last three decades, have evolved as an important branch of plant ecology. In this book, in general, the effects of chemical compounds released from plants (including microorganisms), on other plants in their vicinity are considered under the term "allelopa-thy." The term "allelochemical" is used in a wider context in the field of ecology where it includes, but is not limited to, plant and microorganism interactions. Allelochemicals released from plants (including microorganisms) have multifaceted influences on ecosystems; these also influence soil microbial ecology, soil nutrients, and physical, chemical and biological soil factors. We believe~that it is extraordinarily difficult to separate the influence of allelochemicals on each of these components of an ecosystem. Effects on any one of these components, due to allelochemicals, may influence growth, distribution, and survival of plant species. The aim of this book is to provide insight and recent progress on allelochemical research from this multifaceted standpoint. Research articles-reporting results of substantially completed work, and review articles-presenting novel and critical appraisals of specific topics of interest, are included. Yet it may not be a comprehensive treatise on the subject. The sequence of chapters in the book starts with an overview followed by 34 chapters contributed by scientists around the world, thus presenting a global perspective on allelochemical research. Section I-Methodologies (Chapters 2-8), discusses important aspects of methodology in the study of allelopathy, shortcom-ings of bioassays for allelopathy, bioassays for different plant groups, extraction of allelochemicals from soil, sampling procedures, and an outline of analytical methods for different classes of allelo-chemicals. Section Il-Interactions Among Plant and Microbial Systems (Chapter 945), presents allelochemical research in aquatic and terrestrial ecosystems, and includes other important subjects like pollen allelopathy. Section Ill-Ecological Aspects (Chapters 16-22), illustrates the signifi-cance of ecological studies in allelochemical research, and discusses the important role that the soil environment plays in the functioning of allelochemicals. Section IV-Biochemical, Chemical and Physiological Aspects (Chapters 23-30), discusses biochemical, molecular, and physiological aspects of allelopathy, including information on modes of action of allelochemicals in allelopathy. Allelochemicals have been successfully used in biocontrol of plant pathogens and weeds. This important applied aspect of allelochemistry is discussed under Section V-Biological Control of Plant Disease and Weeds: Applied Aspects (Chapters 31-34). Thus, in totality, the book illustrates the processes, procedures, and applications related to allelochemicals.

This is the first comprehensive and up-to-date reference on the science, mechanism, methodology, and application of allelopathy. The objective of this practical reference is to report on the latest advances by inviting leading scientists to contribute in specific fields. The volume is organized under three major subsections: History of allelopathy, Allelochemicals, allelopathic mechanisms, and bioassays, and Application of allelopathy in agriculture and forestry.

There are many good books in the market dealing with the subject of allelopathy. When we designed the outline of this new book, we thought that it should include as many different points of view as possible, although in an integrated general scheme. Allelopathy can be viewed from different of perspectives, ranging from the molecular to the ecosystem level, and including molecular biology, plant biochemistry, plant physiology, plant ecophysiology and ecology, with information coming also from the organic chemistry, soil sciences, microbiology and many other scientific disciplines. This book was designed to include a complete perspective of allelopathic process. The book is divided into seven major sections. The first chapter explores the international development of allelopathy as a science and next section deals with methodological aspects and it explores potential limitations of actual research. Third section is devoted to physiological aspects of allelopathy. Different specialists wrote about photosynthesis, cell cycle, detoxification processes, abiotic and biotic stress, plant secondary metabolites and respiration related to allelopathy. Chapters 13 through 16 are collectively devoted to various aspects of plant ecophysiology on a variety of levels: microorganisms, soil system and weed germination. Fundamental ecology approaches using both experimental observations and theoretical analysis of allelopathy are described in chapters 16 and 17. Those chapters deal with the possible evolutionary forces that have shaped particular strategies. In the section named “allelopathy in different environments”, authors primarily center on marine, aquatic, forest and agro ecosystems. Last section includes chapters addressing application of the knowledge of allelopathy.

Invasive plants have an impact on global biodiversity and ecosystem function, and their management is a complex task. The aim of this book is to discuss fundamental questions of invasion ecology, such as why particular communities become more invasible than others, what the mechanisms of exclusion of native species by invaders are, and whether invasion can be predicted. In addition, agricultural practices influencing invasion, the environmental and economic costs of invasion as well as possible management strategies are discussed. Readers will get a unique perspective on invasion ecology through employing general principles of ecology to plant invasions.

Chemical Ecology is a component of Encyclopedia of Chemical Sciences, Engineering and Technology Resources in the global Encyclopedia of Life Support Systems (EOLSS), which is an integrated compendium of twenty one Encyclopedias. The Theme on Chemical Ecology provides the essential aspects of the chemicals involved in the interactions of living organisms. It deals with studies involving defensive chemicals which are utilized to deter potential predators, which may attack a wide variety of species, animal interaction, aquatic ecosystems, chemical ecology and pest management, relation to medicine and pharmaceuticals. This volume is aimed at the following five major target audiences: University and College students Educators, Professional practitioners, Research personnel and Policy analysts, managers, and decision makers.

The increase in organic farming and concerns about potential negative effects on human health and the environment is creating a demand for pesticide-free food and alternative weed management techniques. This book provides a comprehensive examination of non-chemical weed management.