Curious biological phenomena occur where land and sea alternate at low and high tides. Large crop-like populations of the perennial sea lavender (Limonium vulgare) appear and disappear over the years. Such vegetations are of great beauty, especially at bloom, and form a tourist attraction. Despite the extreme physical conditions they teem with life, among which are fertilising insects and fungi which cause plant disease. This book describes how long-lived sea lavender populations come and go, and how the fungal diseases "rust" and "mildew" may contribute to their going. The temporal and spatial distributions of rust and mildew epidemics are described. The annual cycle and the perennation of the rust (Uromyces limonii) are studied in detail. The unusual but important roles of sea water in the dispersal of the host plant and of its rust are sketched. The possible function of differential host resistance and of differential rust virulence is indicated. Data on the biology of sea lavender mildew (Erysiphe limonii) suggest that mildew and rust differ in lifestyle. Tolerance of sea lavender plants to rust and mildew is heritable and important, but does it last forever? Some theoretical implications for botany and phytopathology are tentatively discussed, especially the role of equilibrium or homoeostasis. However, the main focus of the book is on the facts collected in the salt marshes of the barrier island Terschelling, in the north of the Netherlands. This book with about 100 tables and some 100 figures provides new information of importance to botanists, plant pathologists, population biologists and general ecologists.

What makes the book so compelling is that it includes a thorough review of available experimental and empirical evidence for all the processes described. The author is also consistent in pointing out missing knowledge, and identifies numerous instances where experimentation is necessary to bridge the gaps between empiricism and theory. The examples, and the knowledge hiatuses, are an immense contribution, and will serve well as teaching aids and to stimulate, design, and implement further research.

This Handbook supersedes Department bulletin 1366, "A check list of diseases of economic plants in the United States," issued in 1926. It replaces the processed report, "Index of Plant Diseases in the United States," issued in six parts, from 1950 to 1953. The Handbook does not constitute a revision of the "Index," issued from 1950 to 1953. There are no real changes in content. Condensation of the introductory explanation, and some minor changes, mainly in the host descriptions, to permit better arrangement of the printed page, are the most conspicuous differences from the original "Index."

Set includes revised editions of some issues.

This book demonstrates that long-term experimentation and monitoring are vitally important in understanding changes that are occurring in the environment and the way they interact with agriculture and natural ecosystems. Chapters are based on papers presented at a conference held in July 1993, to celebrate the 150th anniversary of Rothamsted Experimental Station. During these 150 years of agricultural research a unique set of field experiments have run continuously for all or most of that time. These experiments, originally set up to study the nutrient requirements of arable crops, now provide a unique resource that is relevant to sustainability, environmental impact and climatic change. The book consists of 22 chapters and covers a wide range of topics including descriptions of various long-term experiments in the USA, Australia, Eastern Europe and Africa, as well as studies at Rothamsted. It will interest a very wide range of readers in agronomy, soil science, forestry, ecology and environmental science.

Plant diseases and pests are a major constraint to agricultural production despite the various measures used to control them. Chemical control, although often e~~ective, may pose environmental hazards and is relatively expensive, especially in developing countries where it may be completely uneconomic. Control through genetically mediated resistance to diseases and pests, is both cheap and environmentally sa~e and at present most diseases and pests o~ staple ~ood crops are controlled through some form of resistance. One of the basic problems in the use of resistance is its ~re quent lack of durability; very often a type of resistance is used that 'breaks down' after a certain period. The temporary nature of this resistance, due to the development of new strains of pest or pathogen able to overcome it, has seriously hindered the improvement o~ the yield potential of many crops as a continuing effort is needed to replace old cultivars who resistance has failed, with new ones. Following Vanderplank's now classical publications (1963, 1968) which differentiated horizontal and vertical resistance, studies on several host-parasite systems have shown that di~ferent types of resistance can be distinguished genetically and epidemiologically, and on the ability o~ the pests or pathogens to adapt to them. A knowledge of how resistance operates at the population level has also opened up possibilities of 'managing' relatively simple resistance types in such a way that a stable host-pathogen system can be pro duced with a minimum of crop loss.