This 1975 book deals with one of the world's fastest disappearing natural resources - the invaluable reservoir of genetic variability in our cultivated plants which have evolved since our forebears began to domesticate them some 10,000 years ago. The preservation of these 'genetic resources', as they have come to be called, is vital to mankind. Without them the geneticists and plant breeders cannot breed the new varieties needed to feed the world's population by providing more disease-resistant strains of our food plants. This volume explores topics such as how to collect and preserve this variation. It ends with a section on how these activities are planned on a world scale through the medium of FAO and other international agencies, and with the participation of scientists from developed and developing countries. This book will be of use as an intelligently written work of much historic value.