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Books > Professional & Technical > Agriculture & farming > Forestry & silviculture: practice & techniques
Legumes and oilseed crops are a rich source of protein and energy. The major objectives in grain-legume breeding are to increase grain yield, protein quantity and quality and digestibility, and to decrease toxic fac- tors, seed hardness and cooking time. Similarly, oilseed crops such as brassicas and peanut share somewhat similar genetic improvement goals, but suffer from susceptibility to a number of pathogens and diseases. In spite of the best efforts through conventional breeding, their yield has been virtually static, with no significant breakthrough. The lack of genetic variability in the base population has been considered to be a major limiting factor for the slow progress made in the improvement of these crops. The desired goals can be achieved by incorporating addi- tional genetic variability in the existing germplasm. The protein and oil contents which are genotypically oriented can be enhanced further by suitable crosses. In this regard, progress made during the last decade, in the area of in vitro manipulation and recombinant DNA technology, holds promise for the improvement of these crops. Among the oilseed crops, Brassica spp. , soybean and sunflower have been well studied, wherein haploids, somaclones, somatic hybrids, cybrids and transformed plants have been produced. Oilpalm is one of the best examples where micropropagation is being commercially prac- ticed. Regarding legumes, though there is extensive work on forages, such as Medicago and Trifolium, much needs to be done on food legumes.
Forty chapters deal with various aspects of tissue culture, in
vitro manipulation, and other biotechnological approaches to the
improvement of maize.
Salinization of soils is a major threat to irrigated agriculture and counteracts the targets of costly public infrastructure investments. In this study, salinization is regarded as the outcome of an institutional arrangement which impedes the effective implementation of well-known and well-established control measures be they technical, managerial or economic. In public irrigation systems neither the management units nor the farmers are offered any incentives towards the control of high groundwater levels and salinization if the management units are embedded in a highly centralized non-market institutional setting. The author answers the question under which conditions management units and irrigators are active in halting and reversing the process of salinization.
Of all the food produced in the world one third is lost to insect pests, weeds and diseases, and the total world population is estimated as growing from 4000 million in 1975 to about 6000 million by the year 2000. To satisfy these needs, the world's farmers must meet the extra requirement every year. The easiest way in which farmers can increase the amount of food they produce is to prevent the loss due to pests. The biological control measures which were once thought to be the safest methods of pest control have, as we now know, not proved successful on a commercial scale. In such a dismal situation the only solution is to use pesticides to save the losses from pests and to increase the crop yield. Apart from agriculture, pesticides have also contributed much to human com fort by controlling the vectors of typhoid, malaria, sleeping sickness, filariasis, dengue hemorrhage fever, plague etc. On the other hand, the indiscriminate use of insecticides and their harmful effects on nontarget organisms has attracted much attention from people in all walks of life, for example, scientists, administrators, the press and the public. The harmful effects of insecticides on higher organisms such as birds, fish and mammals are easy to observe and have received much attention. However, the interactions of insecticides with microorganisms such as bacteria, fungi, algae and protozoa have gone unnoticed until recently."
Recently, the pharmaceutical industry has shown considerable interest in the en masse micropropagation of elite plants, and the large-scale produc- tion of secondary metabolites in plant cell cultures through the use of bioreactors. This is now being realized by the selection of high-yielding somac1ones or through the production of hairy roots by transformation with Agrobacterium rhizogenes. These new developments need to be high-lighted and brought to the attention of workers dealing with medicinal, aromatic, and other plants of industrial importance. A series of books on the biotech- nology of medicinal and aromatic plants is therefore being compiled to provide a survey of the literature focusing on recent information and the state of the art. This book, Medicinal and Aromatic Plants IV, like the previous three volumes (Medicinal and Aromatic Plants I, II, and III, published in 1988, 1989, and 1991, respectively) is unique in its approach. It comprises 28 chapters dealing with the distribution, economic importance, conventional propagation, review of tissue culture studies, and the in vitro production of important medicinal and pharmaceutical compounds in various species of Ammi, Bergenia, Canavalia, Capsicum, Cassia, Cephaelis, Cornus, Cucurbita, Elettaria, Eupatorium, Genipa, Gentiana, Gypsophila, Hygrophila, Leon- topodium, Nerium, Picrasma, Polygonum, Ptelea, Rheum, Scopolia, Silene, Solanum, Strophanthus, Tagetes, Thymus, and Uncaria. This book is tailored to the needs of advanced students, teachers, and research workers in the fields of plant biotechnology and chemical engineer- ing, pharmacy, botany, and phytochemistry.
In continuation of Volumes 8 and 9 (1989) on in vitro manipulation of plant protoplasts, this new volume deals with the regeneration of plants from protoplasts and genetic transformation in various species of Agrostis, Arabidopsis, Atropa, Brassica, Catharanthus, Datura, Cucumis, Daucus, Digitalis, Duboisia, Eustoma, Festuca, Helianthus, Hordeum, Kalanchoe, Linum, Lobelia, Lolium, Lotus, Lycium, Lycopersicum, Mentha, Nicotiana, Pelargonium, Pisum, Pyrus, Salvia, Scopolia, and Solanum.These studies reflect the far reaching implications of protoplast technologyin 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.
In keeping with the spirit of an Advanced Series in the Agricultural Sciences, we have attempted to address herein most of the current research areas being used to characterize, describe and manage salt-affected soils. Because of a certain amount of personal bias inherent in our individual viewpoints and backgrounds, some areas have been accorded more emphasis than others. It has been our goal, however, to provide either detail about, or at least a recent reference to, each major area of current soil salinity research. This information, coupled with what we hope to be a rather logical progression from descriptive material on equilibrium or near-equilibrium soil chemistry, through transport processes, to eventual management practices including some elementary economic decisions, should enable the reader to bridge the gap from introductory soil chemistry or soil physics texts to the basic literature of this area. The text will be perceived by the astute reader as somewhat uneven in its treatment of respective sections. We feel that this is to a certain extent appropriate, for it thus portrays the unevenness of progress to date in the corresponding areas of research. The management of saline and sodic soils remains largely an empirical semi-science or even art, whereas transport phenomena are normally dealt with in a much more theoretical (and also a much more highly mathematical) vein. Equilibrium soil chemistry has historically occupied an intermediate position with respect to its mix of empiricism and theoretical rigor.
Although biologists have directed much attention to estimating the
extent and causes of species losses, the consequences for ecosystem
functioning have been little studied.
Part A and Part B of the fifth of twelve volumes of The Mycota deal
with the mechanisms of interactions between fungi and plants and
consider pathogenic as well as mutualistic associations.
The floricultural industry has been undergoing an unprecedented revolu tion in terms of the type of commodity produced and the production and marketing technology in both developed and developing countries. As a result of this revolution, as we know today, there is a flower for every purpose and for every person in the world, as is evident from the slogan of the Society for American Florists: "say it with flowers." In re cent years, the Latin American and European countries have become sizeable competitors for the North American fresh flower markets and the trend continues growing. Like any other crop production, floricultural production can be divided into three basic factors: (1) production costs (2) quality (3) transportation costs. All these must be optimum for this area or industry to be safe from competition. With increasing consumer awareness and the current recession, the pressure from the artificial floral products in dustry and also of neighbouring countries on the American fresh flower industry, and continued competition even amongst the growers, whole salers and retailers, quality in floricultural industry is becoming increas ingly important to all those concerned with handling these products. The visual quality aspects of the product are the sole determiner of consumer acceptability in this industry and, unlike fruits and vegetables, flowers cannot be marketed by just discarding the damaged portion."
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.
This seris keeps scientists and advanced students specialized on a particular subject informed of the latest developments and results in all different areas of botany. The present volume includes reviews on structuralbotany, physiology, genetics, taxonomy, geobotanic, as well as a contribution treating seed dispersal.
Hydroponics, the method of growing plants without soil, presents a
feasible alternative to conventional farming in areas which are
short on water supply and limited in agricultural soil.
Photochemical oxidants are secondary air pollutants formed under the influence of sunlight by complex photochemical reactions in air which contains nitrogen oxides and reactive hydrocarbons as precursors. The most adverse components formed by photochemical reactions in polluted air are ozone (0 ) 3 and peroxyacetyl nitrate (PAN), among many other products such as aldehydes, ketones, organic and inorganic acids, nitrates, sulfates etc. An analysis and evaluation of the available knowledge has been used to characterize the relationships among emissions, ambient air concentrations, and effects, and to identify the important controlling influences on the formation and effects of photochemical oxidants. The biological activity of photochemical oxidants was first clearly manifested during the early 1940's, when vegetation injury was observed in the Los Angeles Basin in the United States. Since that time, as a consequence of the increasing emissions of photochemical oxidant precursors, the photochemical oxidants have become the most important air pollutants in North America. In other parts of the world, for example South and Central America, Asia, and Australia, photo chemical oxidants threaten vegetation, particularly the economic and ecological performance of plant life. According to my knowledge, the first observations of ozone and PAN injury to vegetation in Europe were made by Dr. Ellis F. Darley (Statewide Air Pollution Research Center, University of California, Riverside, California) during a study visit (1963/64) to the Federal Republic of Germany."
Forest damage, forest decline, forest dieback - not related to biotic agents - is occurring in the Atlantic and Pacific regions. In Europe and Eastern North America this serious problem is considered to be, at least to some part, related to industrial air pollutants and their atmospheric conversion products, such as acid rain or ozone. Forest declines in the Pacific region have been attributed largely to natural causes involving forest dynamics, since air pollution and other negative anthropogenic influences are practically absent. Presented here are typical decline phenomena in the Pacific and Atlantic region, potential causes, effects and mitigation strategies, and the question whether there are any similarities on a functional or structural basis is addressed.
of metal interactions with subcellular biochemical systems usually either are metabolites of the system affected (porphyrinurias) or represent some specific function of a cellular system being impaired (proteinurias). One typically finds a continuum of symptoms, from the subtle or so-called "no effect" bio chemical and physiological indicators of exposure to severe clinical disease and death. This continuum is the basis of much of the controversy since many health officials follow the traditional practice of applying the "threshold health-effect" concept in evaluating the problems of environmental exposure to metals. The past decade or so, however, has seen a vast increase in our understanding of the effects of elevated concentrations of toxic metals in local populations and ecosystems. At the same time, there is a growing awareness that the effects of the metals which occur naturally in the environment must be distinguished from those imposed by the pollutant fraction. This point was amply document ed in a recent study of cadmium intake and cadmium in a number of human tissues in Sweden, Japan, and the United States, which showed fairly conclu sively that the background exposure in Japan was about threefold higher than in the other two countries (2). One immediate implication is that any health ef fect studies of cadmium in Japan using control groups within that country are liable to underestimate the difference between the exposed and the control groups simply because of the the high "background" intake."
John Sculley In the short history of personal computing, the task of the software programmer has been one of the least recognized-but one of the most significant-in the industry. In addition to defining the prob lems, and presenting the solutions, the software programmer is con fronted with the challenge of having to predict what combination of ideas and technologies will move the industry forward in the most compelling way. Even though we've seen the development of tremendous applications in a surprisingly short period of time, the most difficult problems often surface when we try to elevate a suc cessful local idea to the international arena. In the case of Apple Computer, these challenges become especially profound when you consider that Apple sells Macintosh not just in the United States, but in Japan, China, the Middle East, Africa, East ern Europe, and even to the United Nations itself. Of course, this means that the personal computer must work everywhere around the world. But more significantly, it also means that the software must reflect the uniqueness of a given culture, its language, morals, and even its sense of humor. To step away from a narrowly-defined, nationally-based paradigm for software development, programmers, management, and entire corporations must learn to recognize what elements of an interface, problem solving technique, documentation illustration, package de sign, and advertisement are local, and which elements are appro priate for global markets."
Neurochemical Techniques in Insect Research properly emphasizes the insect. It only scratches the surface of the exploding repertoire of general neuro chemical techniques that can be applied to insect research in 1985. But it al so presents the advantages of using insects for studying certain biological questions that are approachable by neurochemical techniques. Even more so, it summarizes the long list of unique problems encountered in attempting to study insects by neurochemical techniques. As in other volumes of this series, the contributors to this volume are the authorities in the field. They themselves have developed much of the material presented. Thus the sum effort provides a true description of the state of the art; and, pleasantly, it does so in a very complete and clear manner. Readers of this series will not need to be reminded that, despite the fact that vertebrates make up only about 3% of all animal species, research in in vertebrates such as insects has lagged behind that on vertebrates, at least in the neurochemistry area; the relative simplicity and large cell size of the in sect nervous system has always provided incentive for work in neurophysiol ogy and neuroanatomy. Toxicology interests will always stimulate a certain amount of work on insect neuropharmacology, and insects are extremely suitable for several areas of toxin research. Last but not least, the insects are beautiful organisms for which the applications of genetics can be made to the study of nervous system function."
In order to provide meaningful information for evaluating environmental consequences of alternative control strategies of air pollutant emissions, scientists have recently initiated numerous studies aiming at collecting and making use of regional data. New kinds of mathematical models have been developed that no longer are calibrated just for individual stands or catchments but can be applied on a large regional scale. Such regional models and data were reviewed at a meeting" Models to describe the geographic extent and time evolution of acidification and air pollution damage", organized by the Finnjsh Research Project on Acidification (HAPRO), and held in Aulanko, Hiimeenlinna, Finland, July 5-8, 1988. This volume is based on the outcome of that meeting. The chapters of the volume are written by leading scientists in the field. The main objective of this volume is to discuss the potential of regional models to analyze the geographic extent of acidification as well as the environmental damage and the time evolution of:the responses of the environment. First, in Part I of the volume, sensitivity distributions of ecosystems, forest soils and surface waters are described. The focus of interest is therefore extended from the most sensitive ecosystems to sensitive and moderately sensitive parts of the environment. When formulating national and interna tional targets, it is of crucial importance to know the whole distribution of critical loads within the area, and not only the level the most sensitive ecosystem can tolerate.
The rapid increase in environmental measurements during the past few decades is associated with (1) increasing awareness of the complex relations linking biological responses to atmospheric variables, (2) development of improved data acquisition and handling equipment, (3) the application of modeling to environmental problems, and (4) the implementation of large, cooperative studies of international scope. The consequences of man's possible alteration of the environment have increased our interest in the complex nature of biological responses to meteorological variables. This has generated activity in both measurements and in the application of modeling techniques. The virtual explosion of modeling activity is also associated with the development oflarge computers. The testing of these models has demonstrated the need for more, different, and better environmental data. In addition, technological developments, such as integrated circuits, have reduced the cost, power consumption, and complexity of data acquisition systems, thus promoting more environmental measurements. The emergence of scientific cooperation on a global scale has increased measurement activities markedly. The International Geophysical Year (1958) has been followed by the International Hydrologic Decade, the Inter national Biological Program, the Global Atmospheric Research Program, and a host of environmental studies of a regional nature that have all emphasized field data collection."
The Daniel S. Lehrman Memorial Symposia Series will publish the proceedings of symposia devoted to the evolution, development, and organization of behavior. These various symposia will bring together at intervals scientists studying problems from each of these view points. The aim is to attempt to integrate our knowledge derived from these different sources and to familiarize scientists working on similar behavior patterns with the work of their colleagues in related fields of study. Each volume, therefore, will be devoted to a specific topic in the field of animal behavior, which will be explored with respect to its evolutionary aspects, including the adaptive nature of the behav ior; with respect to its developmental aspects, including neural, hor monal, and experiential influences; and with respect to the analysis of features of organization, including motivational, perceptual, and motor aspects and their physiological bases. It is our feeling that the most appropriate memorial to our colleague and close friend, Daniel S. Lehrman, is the continuation of his valuable contributions toward integrating these approaches to the study of animal behavior, which he pursued so effectively during his own life. Daniel S. Lehrman's lifelong love and study of animal behavior gave us a wealth of new insights into reproductive behavior and evolution. It is therefore appropriate that the first symposium of this series is devoted to recent advances in this field.
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.
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. |
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