註釋 Roots play a critical role in the efficient uptake of water and nutrients from the soil through adaptation of its architecture, construction plasticity, specialized structures, physiological responses and beneficial relationships with microorganisms. Roots also serve as storage organs for carbohydrates, they anchor plants in soil and may act as perennating structures that last for many years. However, information on the genetic analysis of root traits is scarce and few characterized root mutants of crop plants are available, mainly because of the difficulty in accessing and studying this below ground organ. A Coordinated Research Project was implemented in 19992004. This publication is a collection of 14 research articles describing the work and achievements made by the participants, covering topics from methodologies for evaluating root structure and function, induced root mutants, and molecular genetic and physiological analysis, as well as other related studies in different crops. This publication will provide a basis for the prevalent generation, selection and use of root mutants in crop improvement programs.--Publisher's description. 