水稻苗期耐Cu^(2+)胁迫QTL遗传分析

Genetic analysis of QTLs for tolerant to high Cu^(2+) stress at seedling stage of rice

利用栽培稻优良品种"特青"与普通野生稻"元江普野"构建的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硫酸铜(150mg/L)胁迫处理;处理15d后,以苗高、鲜重及干重抑制率的平均值作为考察苗期耐Cu2+胁迫指标,用于QTL定位分析。结果表明,以苗高、鲜重及干重的平均抑制率作为胁迫指标,共检测到11个与硫酸铜胁迫相关的QTL,分别位于第1、第2、第6、第7、第8、第9以及第10染色体上;其中,RM11和RM118(Chr 7)、RM337和RM152(Chr 8)以及RM105、RM219、RM296(Chr 9)附近的7个来源于栽培稻亲本特青等位基因的QTL位点,表现为耐硫酸铜胁迫;RM1(Chr 1)、RM318(Chr 2)、RM176(Chr 6)以及RM222(Chr 10)附近的4个来源于野生稻等位基因的QTL位点,表现为耐硫酸铜胁迫。虽然检测到的QTL位点较多,但每个QTL的作用相对较小,表明调控水稻幼苗耐铜毒性的遗传机制较为复杂。

The DH population consisting of 139 recombination lines, derived from the cress between common wild rice as the donor parent and fine varieties of cultivated rice Teqing as recurrent parent and their genetic linkage maps were employed to map QTLs controlling tolerant to Cu^2＋ stress at the seedling stage by culturing the seedling in the concentration of Cu^2＋ （150 mg/L） when the second leaves fully carried out. After 15 days of treatment, the avemge inhibition rate of seedling height, fresh weight and dry weight were measured as index for tolerant to Cu^2＋ stress. The results indicated that a total of 11 QTLs were detected under Cu^2＋ stress by using the avemge inhibition rate of seedling height, fresh weight and dry weight as stress indicators. They were located on chromosome 1, 2, 6, 7, 8, 9 and 10. Among them, near RM11, RMll8 on chromosome 7, RM337, RM152 on chromosome 8 and RM105, RM219, RM296 on chromosome 9 from alleles of cultivated rice Teqing QTL loci, expressed as tolerant to Cu^2＋ stress; near RM1 on chromosome 1, RM318 on chromosome 2, RM176 on chromosome 6 and RM222 on chromosome 10 from alleles of wild rice QTL loci, expressed as tolerant to Cu^2＋ stress. From the point of view of test results, the QTL position spot are many, and each QTL has a relatively small role, indicating the genetic mechanism of tolerance to copper toxicity in rice seedling stage is more complicated.