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Plant Breeding for Pest and Disease Resistance. By G. E. Russell. London: Butterworth (1978), pp. 485, £25.00.

This book is based on the Proceedings of an International Conference held in Ibadan, Nigeria in 1975, with 28 contributors giving wide geographical cover and outlook. The first half deals with basic aspects of soil and water conservation, the characterization of soils and rainfall in relation to erosion hazard, and management for erosion control. The second half deals with erosion in relation to farming systems in Africa, the Far East and Central and South America. The book is much more than the familiar catalogue of devastation, and for the most part concentrates on experimental findings unified by the Universal Soil Loss Equation, which seems to offer the best prospect for translating results from one region to another, though it clearly needs much refinement as the critical discussion of its application in West Africa by E. Roose reveals. The editors have done well to arrange so many contributions coherently, without undue overlapping. A good index is helpful in tracing themes through the many chapters. I particularly enjoyed J . M. Kowal and A. H. Kassam's detailed analysis of rain drop sizes and energies at Samaru, Northern Nigeria. Rainstorms in the tropics are more intense than in the regions of early erosion research such as the mid-Western USA. The classical methods and remedies worked out there need critical understanding before they are applied elsewhere. This volume is a valuable summary of the experience of soil scientists in the tropics.