The development of plant roots: new approaches to underground problems.

The roots of terrestriaf plants are involved in the acquisition of water and nutrients, anchorage of the plant, synthesis of plant hormones, and storage functions. The development of a root system involves strategies that are common to the development of all plant organs, as well as certain aspects that are unique to roots. Despite the importance of roots and some unusual developmental characteristics, the study of root morphogenesis has not received as much attention as the development of aerial plant organs. This has been particularly true for studies at the molecular and genetic levels. This review is designed to highlight some of the interesting aspects of root development and to describe recent molecular genetic approaches that are likely to advance our understanding of root development.