水稻加工品质数量性状基因座(QTLs)分子定位研究

Molecular Mapping of QTLs for Rice Milling Yield Traits

检测了Lemont/特青RI群体 2 12个株系的糙米率 (BR)、精米率 (MR)和整精米率 (HR)等 3项加工品质性状 ,利用RFLP连锁图和线性模型的复合区间作图方法 (QTLMapperV1.0 )进行QTL定位研究。群体呈连续分布 ,双向超亲现象明显 ,HR较BR、MR变异范围更大并偏向低值方向 ;分别检测到 1个MR、4个HR主效QTL ,其中QHr6和QHr7等 2个基因座具有较大遗传效应 ;分别检测到 12对影响BR、5对影响MR、16对影响HR的上位性基因座 ,上位性效应的影响大于主效QTLs。

QTLs of three milling yield traits,including brown rice (BR,%),milled rice (MR,%) and head milled rice (HR,%),were mapped using a set of 212 Lemont/Teqing RI population,an RFLP linkage map with 182 markers and a mixed model approach(QTLMapper V1.0). The population showed continuous distributions with transgressive segregation on both sides for all traits while HR had a wider variation than BR and MR. One and four main effect QTLs were detected for MR and HR. Two QTLs for HR( QHr6 and QHr7 ) had large additive effects. Twelve,five and sixteen pairs of digenic epistatic loci were associated with BR,MR and HR respectively. Epistasis was more important than main effect QTLs according to the mapping result. A complex relationship was observed for epistatic pairs mapped in same trait or among different traits by sharing intervals.