Plant Nutrition - From Genetic Engineering to Field Practice, the 12th International Colloquium on Plant Nutrition, is the latest in a series which began in 1954. Early meetings were mainly concerned with the practical problems of soil fertility, with soil assessment, fertilizer requirements and methods of analysis. As the colloquia have progressed, the emphasis has slowly changed. The practical problems are still important, but there is increasing emphasis on plant physiology, plant biochemistry, membrane biochemistry, and even on the chemistry of genes which control the proteins...