Question: do all dicot plants have tap root system

Answer: Yes, Dicots, one of the two divisions of angiosperms, start with a taproot, which is one main root forming from the enlarging radicle of the seed. The tap root can be persistent throughout the life of the plant but is most often replaced later in the plant's development by a fibrous root system. A persistent taproot system forms when the radicle keeps growing and smaller lateral roots form along the taproot. The shape of taproots can vary but the typical shapes include: