Soil acidity is a major limitation to crop production in many parts of the world. Plant growth inhibition results from a combination of factors, including aluminum, manganese, and hydrogen ion toxicities and deficiencies of essential elements, particularly calcium, magnesium, phosphorus, and molybdenum. Agricultural management practices and acid precipitation have increased acid inputs into the ecosystem and heightened concern about soil acidity problems. While application of lime has proved to be effective in ameliorating surface soil acidity in many areas, significant soil acidity problems still exist. Scientists from Alberta, Canada, recognized the need to provide a forum for researchers from different disciplines to exchange information and ideas on solving problems of plant growth in acid soils. As a result of their efforts, the First International Symposium on Plant-Soil Interactions at Low pH was held at Grande Prairie, Alberta, Canada, in July 1987. In many acid soil areas, liming materials are not readily available, the cost may be prohibitive, or subsoil acidity cannot be corrected by surface application of lime. New management approaches involving both the plant and the soil are needed in these situations. Progress has been made in the selection and breeding of acid-tolerant plants. However, continued progress will be limited by our lack of understanding of the physiological and biochemical basis of differential acidity tolerance among plants.

Zusammenfassung
' The proceedings are highly recommended for libraries to purchase they are a valuable source of references for those interested in problems of crops and natural vegetation on acid soils. ' Plant breeding 108 1992
' The well edited book is a valuable text for everyone dealing with problems of productivity in acids soil; as suggested by the title, subjects covered in the proceedings will be directed to reasearchers concerned with soil fertility and encironment as well as to scientists interested in the latest developments on a wide range of topics related to soil acidity and plant growth. ' Agrochimica 36:3 1992

Inhalt
Section 1: Chemistry of acid soils.- Section 2: Fertility of acid soils.- Section 3: Management of acid soils.- Section 4: Microbial relations in acid soils.- Section 5: Physiology/Biochemistry of acid stress tolerance in plants.- Section 6: Identification of acid tolerant plants.- Section 7: Genetics/Breeding of acid tolerant plants.