短語詞組短語backcross progeny 回交子代Backcross population 回交群體Inverse backcross 反回交double backcross 雙向回交;雙反交backcross method 回交法incomplete backcross 不完全回交gamete backcross 配子回交interspecific backcross 回交Nullisomic backcross 小黑麥異代換系 返回 backcross