Recent Developments in Insect Neurohormones


Book Description

The most striking fact revealed by investigations of insect neurohormones is that insects are as well supplied with neurohormones as mammals, since neurohor mones regulate not only the functioning of the endocrine glands, prothoracic gland, and corpora allata, but also most physiological processes. Our knowledge of neurohormones developed originally from anat omocytological investigations and experimental studies. Today, accurate bio assays have been devised for studying both in vivo and in vitro physiological processes, and RIA determination has yielded knowledge of titer modifications of humoral factors. Much is also known about neurohormone purification, and several neurohormones have even been identified in different species. Immunocytochemistry has made it possible to demonstrate in their origin and release sites the presence of insect neurohormones whose structure has been elucidated. Moreover, the presence of vertebrate and invertebrate neuropeptides has been demonstrated in insects. As regards biogenic amines, methods of detection have been greatly refined and it is now possible to identify the cell bodies and axons of the main biogenic amines. Other new methods, such as cobalt chloride impregnation or Lucifer yellow staining, have revealed the axonal pathways and the location of particular neurons. The mechanisms of action of neurohormones have been investigated in several cases and the results of these investigations will be related in the chapters which follow.




Insect Neurohormones


Book Description

The discovery of insect neurohormones dates from the earliest experimental in vestigations in insect endocrines, and the matter cannot be discussed without evoking the names of its pioneers-Kopec, Wigglesworth, Fraenkel. Whereas the experiments demonstrated the existence of the first known neurohormones, the formulation of the concept of neurosecretion was of fundamental importance to further progress, and tribute must be paid to Ernst and Berta Scharrer. The recent proliferation of investigations into insect neurohormones has cre ated the need for an overall review of the data. Our knowledge of the subject is voluminous, and the evidence clearly demonstrates that neurohormones playa part in most insect regulatory processes. This book analyzes and synthesizes the data, starting from neurosecretion (i.e., source sites and release modes of neurohormones) and continuing through the various functions in which neurohormones have been shown to be involved: endocrine gland activity; diapause; reproduction; visceral muscle functioning; color change; behavior; water and ion balance; protein, sugar, and lipid metabo lism; and tanning and other processes occurring at the cuticle level. In each chapter, besides the experimental information, technical procedures as well as recent information concerning purification of the particular neurohor mones and their mode of action are reported. Numerous exhaustive tables allow the reader to get an overview of the matter while the major findings of the mo ment are presented in the conclusion of each chapter.




Hormones and Metabolism in Insect Stress


Book Description

This book discusses the effects of both natural (e.g., temperature, humidity, and lack of food) and man-induced stressors (e.g., pollution) on insects. Insect neurohormones and metabolism are emphasized, although all aspects of insect biology are examined. The role of ecdysteroids and juvenile hormones in response to thermal and other stressors is featured, and population studies in insect stress are presented. Entomologists, ecologists, ecophysiologists, physiologists, applied entomologists and others will find Hormones and Metabolism in Insect Stress an important reference resource.




Neurohormones in Invertebrates


Book Description

This volume provides a particularly timely survey of invertebrate peptide hormones. Interest in invertebrate peptide hormones has focused upon two important and related aspects, both of which are fully covered in this volume. As such, it should have a broad appeal to scientists from a number of disciplines.




Ecofriendly Pest Management for Food Security


Book Description

Ecofriendly Pest Management for Food Security explores the broad range of opportunity and challenges afforded by Integrated Pest Management systems. The book focuses on the insect resistance that has developed as a result of pest control chemicals, and how new methods of environmentally complementary pest control can be used to suppress harmful organisms while protecting the soil, plants, and air around them. As the world's population continues its rapid increase, this book addresses the production of cereals, vegetables, fruits, and other foods and their subsequent demand increase. Traditional means of food crop production face proven limitations and increasing research is turning to alternative means of crop growth and protection. - Addresses environmentally focused pest control with specific attention to its role in food security and sustainability. - Includes a range of pest management methods, from natural enemies to biomolecules. - Written by experts with extensive real-world experience.




Neurobiology of Chemical Communication


Book Description

Intraspecific communication involves the activation of chemoreceptors and subsequent activation of different central areas that coordinate the responses of the entire organism—ranging from behavioral modification to modulation of hormones release. Animals emit intraspecific chemical signals, often referred to as pheromones, to advertise their presence to members of the same species and to regulate interactions aimed at establishing and regulating social and reproductive bonds. In the last two decades, scientists have developed a greater understanding of the neural processing of these chemical signals. Neurobiology of Chemical Communication explores the role of the chemical senses in mediating intraspecific communication. Providing an up-to-date outline of the most recent advances in the field, it presents data from laboratory and wild species, ranging from invertebrates to vertebrates, from insects to humans. The book examines the structure, anatomy, electrophysiology, and molecular biology of pheromones. It discusses how chemical signals work on different mammalian and non-mammalian species and includes chapters on insects, Drosophila, honey bees, amphibians, mice, tigers, and cattle. It also explores the controversial topic of human pheromones. An essential reference for students and researchers in the field of pheromones, this is also an ideal resource for those working on behavioral phenotyping of animal models and persons interested in the biology/ecology of wild and domestic species.




Neurohormonal Techniques in Insects


Book Description

Insects as a group occupy a middle ground in the biosphere between bac teria and viruses at one extreme, amphibians and mammals at the other. The size and general nature of insects present special problems to the student of entomology. For example, many commercially available in struments are geared to measure in grams, while the forces commonly en countered in studying insects are in the milligram range. Therefore, tech the study of insects or in those fields concerned with niques developed in the control of insect pests are often unique. Methods for measuring things are common to all sciences. Advances sometimes depend more on how something was done than on what was measured; indeed a given field often progresses from one technique to another as new methods are discovered, developed, and modified. Just as often, some of these techniques find their way into the classroom when the problems involved have been sufficiently ironed out to permit students to master the manipulations in a few laboratory periods. Many specialized techniques are confined to one specific research labo ratory. Although methods may be considered commonplace where they are used, in another context even the simplest procedures may save con siderable time. It is the purpose of this series (1) to report new develop ments in methodology, (2) to reveal sources of groups who have dealt with and solved particular entomological problems, and (3) to describe ex periments which might be applicable for use in biology laboratory courses.




Insect Neurochemistry and Neurophysiology · 1989 ·


Book Description

This volume contains the proceedings of the Third International Conference on Insect Neurochemistry and Neurophysiology (ICINN'89), which was held at the University of Maryland at College Park, Maryland, on July 10-12, 1989. The ICINN meetings were ini tiated in 1983 at a time when insect neurobiology was emerging as a vigorous sector of entomology, requiring a degree of attention and autonomy long before granted to its sister field, vertebrate neurobiol ogy. The distinctly medical aspects of the latter were replaced by potentiali ties for developing new approaches to insect control, and the difference was reflected in the kind of sponsorship that has made the ICINNs possible. It is to the credit of the sponsors of the present con ference, i. e., Agricultural Research Service, US Department of Agri culture, American Cyanamid, BASF, Dow Chemical USA, E.I. DuPont de Nemours, Monsanto, Nippon Soda, Rohm and Haas, and Sandoz Crop Protection, that they recognized the need for providing a forum for specialized scientific presentations as well as a medium by which ideas and information could be exchanged directly and cooperation could be planned. As in the previous conferences in 1983 and 1986, the ICINN'89 program contained state-of-the-art plenary lectures or reviews by invited speakers as well as shorter research communications pre sented orally or as posters. The latter two are included here in three sections: neuroanatomy, neurochemistry, and neurophysiology.




Insect Neurochemistry and Neurophysiology · 1986


Book Description

The nature and diversity of presentations at the second International Conference on Insect Neurochemistry and Neurophysiology (ICINN--86) held at the University of Maryland on August 4-6. 1986, attest to the vital ity and broad scope of research in insect neuroscience. The present vol ume is a written account of the invited lectures, contributed papers, and posters presented at the conference, and as such, serves as a fair indica tor of the trends in current research in this field here and abroad. The principal portion of this book consists of seven review papers that were presented by invited speakers. Although the topics vary wide ly, they reflect on and emphasize the main theme of the conference, i. e. , the nature and function of molecular messengers that communicate be meen the central nervous system and organs or tissues involved in the growth, development, reproduction, and behavior of insects. This empha sis is continued in the following three sections on neurochemistry, neuro physiology, and neuroanatomy, although no conscious effort was made by the organizers to highlight these particular fields of neuroscience. It is evident that the recent advances in both physical and chemical analyti cal techniques have made possible the acquisition of structurally defined probes, the long sought-after tools for unraveling the secrets of endogen ous communication. Each section of short papers derived from the oral and poster presentations at the conference is prefaced by an overview that highlights and summarizes the section's content.




Neuropeptide Systems as Targets for Parasite and Pest Control


Book Description

The need to continually discover new agents for the control or treatment of invertebrate pests and pathogens is undeniable. Agriculture, both animal and plant, succeeds only to the extent that arthropod and helminth consumers, vectors and pathogens can be kept at bay. Humans and their companion animals are also plagued by invertebrate parasites. The deployment of chemical agents for these purposes inevitably elicits the selection of resistant populations of the targets of control, necessitating a regular introduction of new kinds of molecules. Experience in other areas of chemotherapy has shown that a thorough understanding of the biology of disease is an essential platform upon which to build a discovery program. Unfortunately, investment of research resources into understanding the basic physiology of invertebrates as a strategy to illuminate new molecular targets for pesticide and parasiticide discovery has been scarce, and the pace of introduction of new molecules for these indications has been slowed as a result. An exciting and so far unexploited area to explore in this regard is invertebrate neuropeptide physiology. This book was assembled to focus attention on this promising field by compiling a comprehensive review of recent research on neuropeptides in arthropods and helminths, with contributions from many of the leading laboratories working on these systems.