RSA in dicots
Dicots, such as A. thaliana , has allorhizic root system, i.e., primary roots are the first roots derived from embryo and lateral roots (LR) are formed from cells present in pericycle of primary roots. Pericycle is a layer of tissue present between endodermis and central vascular cylinder (Smith and Smet 2012). Formation of LR varies in various plant species, for instance, in Arabidopsis , LRs arise specifically from protoxlem patch in pericycle cells (Malamy et al., 1997; De smet et al., 2008) whereas in Medicago and tomato, endodermis is also involved in LR formation (Herrbach et al., 2014). Also, root vasculature in Arabidopsis and tomato exhibits diarch symmetry, containing only two xylem poles, whereas in Medicagovascular system is triarch, containing three xylem poles (Chen et al., 2018).