Abstract: A double haploid (DH) population derived from across between an indica female parent IR64 and a japonica male parent Azucena, was used for detecting QTLs with additive effects and their epistasis for rice mesocotyl length under low temperature and moderate temperature germination condition. Four QTLs with additive effects on chromosome 1, 3, 7 and 8, two pairs of QTLs with epistasis effects on chromosome 3, 7 and 12 controlled mesocotyl length with variance explained being 21.62% and 2.27%.Two pairs of additive×environment and epistasis×environment interaction effects of QTLs were also detected,respectively. Molecular marker assistant selecting mesocotyl length of rice was discussed.

Key words: rice, double haploid, mesocotyl length, quantitative trait loci, epistatic analysis

摘要： 应用籼粳交IR64/Azucena的DH群体及其构建的分子标记遗传图谱，在遮光条件下，通过适温和低温逆境下发芽，测定中胚轴长度。采用QTL Mapper 基因定位软件检测控制中胚轴长度的加性效应QTLs和加性×加性上位性QTLs，在第1、3、6、7、8、12等6条染色体上定位了8个控制中胚轴长度的QTLs，其中在第1、3、7、8染色体上定位了4个具有加性效应的QTLs，位于第7染色体的1个加性效应QTL的增长等位基因来自于父本Azucena，它能使中胚轴伸长0.26 cm，其贡献率达17.5%，其余3个加性效应QTLs的增长等位基因来自于母本IR64，能使中胚轴伸长0.10～0.21 cm，在第3、7、12等3条染色体中共检测到2对加性×加性上位性效应，其贡献率分别为21.62%和2.27%，同时各检测到2对加性效应×环境的互作效应和上位性与环境的互作效应。对应用分子标记辅助育种选育中胚轴伸长的矮秆水稻的可能性进行了讨论。

关键词: 水稻, 加倍单倍体, 中胚轴长度, 数量性状位点