EN
The paper reviews the present state of our knowledge on the genetic variation of morphological and physiological characters of the plant root system as well as its implication for nutrition use efficiency. The questions of whether and/or which of the root parameters appear tobe sustainable selection criteria for the low-input breeding are discussed. Although the concept of such use of the root characters seems to be especially substantiated with local soil and climatic conditions, limited knowledge on root inheritance and genotypic variation under stress conditions as weil as methodological problems have led to controversies and skeptical opinions of breeders. Intensive studies are needed to solve the most important questions. Much more attention should be focused on understanding genetic aspects of the interaction (symbiosis) between plants and rhizosphere organisms, especially the VAM mycorrhize. Appropriate strategies for the improving of complex plant adaptation to lower fertilization levels should be fit as a result of cooperation between various disciplines of plant biology.