根莖,根源,起源
Rootstock \Root"stock`\, n. (Bot.) A perennial underground stem, producing leafly s?ems or flower stems from year to year; a rhizome.
rootstock
n 1: a horizontal plant stem with shoots above and roots below
serving as a reproductive structure [syn: {rhizome}, {rootstalk}]
2: root or part of a root used for plant propagation;
especially that part of a grafted plant that supplies the
roots