作物回交导入系的构建与应用

回交导入系是利用回交及标记辅助选择的手段构建而成的遗传与育种材料。经过多代回交，后代材料在轮回亲本的遗传背景下只包含一个或少量供体亲本染色体片段，因此，可作为QTL分析的重要材料。同时，多代回交有利于打破优异基因与不良基因的连锁，优异基因导入到整体表现优良的轮回亲本材料中，进而实现对育种材料的改良。鉴于其一致的遗传背景，导入系在QTL精细定位和基因克隆、QTL间互作研究、遗传验证及作物聚合育种和分子设计育种中均发挥重要的作用。本文对回交导入系的构建及其在作物遗传育种中的应用进行综述。

Construction and application of backcross introgression lines

Backcross introgression lines are genetic and breeding materials constructed by backcrossing and marker-assisted selection.After multiple backcrossing,the progenies only contain one or a few chromosome seg ments of the donor parents in the genetic background of the recurrent parents,so they can be used as important ma terials for QTL analysis.At the same time,multi-generation backcross is beneficial to break the linkage between ex cellent gene and bad gene,and good gene is introduced into the recurrent parent material with good performance,and further improve breeding material.In view of their consistent genetic background,introgression lines play an im portant role in fine mapping and gene cloning,QTL interaction,genetic validation,crop pyramiding breeding and breeding by molecular design.In this paper,the advanced progresses on the construction and application of CSIL population in crop were reviewed.