Dissecting the biological bases of traits of interest in rice: Architecture and development of the root system

Abstract

Rice possesses a fibrous root system made up mainly of adventitious roots also called crown or nodal roots. Roots emerge from the nodes first at the stem base and then from nodes of shoot ramifications. The root system is not easily accessible and therefore difficult to study. For this reason phenotypic breeding for rice varieties with improved root systems remains a challenge. Hence, identification of genetic determinants of root development should considerably improve breeding efficiency. Numerous studies are underway on identifying and characterizing genes controlling root traits on rice and other cereals. In this review, we summarize the latest strategies and some recent results concerning the identification and characterization of root genes and quantitative trait loci affecting root development in rice.