水稻多亲本导入系聚合派生群体对干旱和低氮选择响应的初步定位研究

Primary Mapping of Selection Respondence to Drought and Low Nitrogen Using Multi-parental Introgression-line Pyramiding Derived Population in Rice(Oryza sativa L.)

以广亲和强优势恢复系"中413"为轮回亲本、以10份优良品种作为供体亲本,经过1次杂交,2次回交和3次自交,育成一套多亲本导入系群体,在常规水田、干旱和低氮条件下种植并目测筛选,将入选导入系相互杂交,F2代及其派生家系分别在干旱与低氮条件下种植,目测筛选获得112份导入系聚合后代株系。在上海和海南两地鉴定这112份导入系在干旱(DT)、低氮(LN)、干旱和低氮耦合(DTLN)、正常水肥管理(CK)下的表型,导入系的平均单株产量在两地DTLN和CK处理中均大于轮回亲本。利用117个SSR标记进行基因型分析,对单株产量与标记数据进行单向方差分析,定位到41个与抗旱和耐低氮相关的QTL,其中6个位点在不同的处理中被重复检测到,另有17个位点与导入频率的卡方检验结果重叠。通过连锁不平衡(LD)分析,11个产量相关位点表现出对干旱、低氮选择的同时响应,反映出针对抗旱性和耐低氮特性的聚合育种效应。

A wide-compatible CMS restorer line,Zhong413,was used as the recurrent parent（RP） to develop a population of multi-parental introgression lines（MPIL） by crossing with 10 elite varieties as donors,followed by backcrossing 2 times and selfing 3 times.Pyramiding procedure was conducted by making crosses among MPILs with good agronomical perfomances,according to the visual assessment under normal,drought or low-nitrogen（Low-N） conditions in several seasons.The F2 populations and derived families were grown again under drought and low-nitrogen conditions.A set of 112 pyramiding-derived lines（PDLs） were selected and applied to phenotyping experiments at the two locations of Shanghai and Hainan,each with four treatments including drought（DT）,low nitrogen（LN）,drought and low nitrogen（DTLN）,normal irrigation and nitrogen（CK）.The PDLs was genotyped using 117 SSR markers.Oneway ANOVA detected 41 QTLs for grain yield（GY） under DT,LN,DTLN and CK.17 QTLs overlapped the chromosomal regions detected by χ2 test.Eleven yield QTLs had simultaneous respondenses to selection under both drought and low-nitrogen,showing the effect of pyramiding breeding on both drought and low-N tolerances.