水稻DH群体苗期耐低磷QTL分析

Genetic analysis of QTLs for tolerance to low-phosphorus stress at seedling stage of rice DH population

利用栽培稻优良品种"特青"与元江普通野生稻配制的DH群体139个家系构建连锁图谱,采用蛭石进行水稻幼苗培养,待第2片叶完全展开时进行低磷(1/5P)胁迫处理;处理15d后,以苗期株高、鲜重及干重的平均抑制率作为考察水稻苗期耐低磷胁迫指标,用于QTL定位分析。结果表明,共检测到7个与低磷胁迫相关的QTL,分别位于第8、第9、第11及第12染色体上,即RM339和RM210(Chr 8)、RM105和RM201(Chr 9)、RM202和RM260(Chr 11)、RM277(Chr 12)均来源于野生稻的等位基因QTL位点,表现为耐低磷胁迫,贡献率为8%～20%,加性效应为37.53%～78.23%;RM339及RM105附近的QTL,加性效应及贡献率均较大,可能是主效QTL。

The DH population consisted of 139 recombination lines,derived from the cross between common wild rice as the donor parent and fine varieties of cultivated rice（Teqing） as receipting parent,and their genetic linkage maps were employed to map QTLs controlling tolerant to low-phosphorus stress at the seedling stage by culturing the seedling in the low concentration of phosphorus（1 / 5P） on vermiculite.After 15 days of treatment,the average inhibition rate of seedling height,fresh and dry weights were recorded.A total of 7 QTLs was detected under low-phosphorus stress in seedling height,fresh weight and dry weight.They are located on chromosome 8,9,11 and 12,that is,near RM339 and RM210 on chromosome 8,RM105 and RM201 on chromosome 9,RM202 and RM260 on chromosome 11 as well as RM277 on chromosome 12,from alleles of wild rice QTL loci,expressed as tolerant to low-phosphorus stress.Furthermore,the contribution rate ranged from 8% to 20% and additive effects between 37.53% to 78.23%.More significant additive effects and the contribution rates were obtained especially on RM339 and RM105 in the vicinity of the QTL,which seems to be the main QTL.