Introgression (introgressive hybridization) The introduction of genetic material from one gene pool to another by hybridization and subsequent back-crossing to one or other of the parents.

• 渐渗现象（渐渗杂交）：是通过杂交或其后代与某个亲本回交，遗传物质从一个基因库被引入另一个基因库的现象。