Development Of Single Segment Introgression Lines Of D Chromosomes And QTL Mapping Of Agronomic Traits In Wheat

Common wheat (Triticum aestivum L.) is one of the world’s most important and oldest crop. It’s an ABD genome allohexaploid species. After a long evolution, the genetic basis of common wheat varieties is very narrow, and the D genome is particularly prominent. Now Aegilops tauschii Coss is recognized as common wheat D genome donor, Its D genome was rich in disease resistance, insect resistance, cold resistance, quality and other useful genes, so D genome research on wheat yield、disease、insect resistance and quality improvement is very important. This study was using F8BC1of backcross introgression lines (ILs) materials, recombinant inbred lines which containing wheat AS60genetic background use for the donor parent, Chuanmai32as the recurrent parent. It based on the laboratory pre-molecular genetics linkage maps, backcross combined with marker-assisted selection, Built the carry steadily wheat D genome of single segment introgression lines in F8BC2progenies. And the same time, identification the control of plant height, spike, spike length, fringe festival, total score of sin and ineffective tillers six agronomic traits QTL by the F8BC2groups, obtain the following results:1. Based on carrying chromosome D of F8BCi backcross import department, using backcross combined with molecular assisted selection technology, obtained680materials of F8BC2generation, which carried chromosome D fragment monoclonal. Successively detected580of chromosome D fragments.2. Based on the acquired recombinant inbred lines of D genome genetic map with SSR molecular marker, analysis the second generation of backcross (F8BC2) D genome genetic background, we could find that:chromosome1D contains87import fragments, which coverage rate has81%; chromosome2D contains97import fragments, which coverage rate has86%; chromosome3D contains14import fragments, which coverage rate has100%; chromosome4D contains15import fragments, which coverage rate has80%; chromosome5D contains56import fragments, which coverage rate has80%; chromosome6D contains63import fragments, which coverage rate has95%; chromosome7D contains181import fragments, which coverage rate has98%. The whole genome recombination rate from1.2%to6.9%. Compared the first generation of backcross (F8BC1) with the second generation (F8BC2), the covering rate which has D chromosome introgression fragments of Ae.tauschii decreased.3. Using MapQTL5.0software and the single factor variance model,680of F8BC2population relative agronomic traits QTL analysis, were identified thirty-seven agronomic characters of QTLs:one QTL related to plant height, fourteen QTLs related to ear length, ten QTLs related to the long fringe, two QTLs related to spikelet number, five QTLs related to the total score we have committed iniquity, five QTLs related to the total score to sin. We can also find that three of thirty-seven QTLs can match with the agronomic traits QTL of recombinant inbred lines located:two associated with long fringe interval Xgwm383Xwmc529and Xwmc720-Xbarc225, one interval Xwmc720-Xbarc225associated with plant height.4. Established the D genome of Ae.tauschii single segment introgression lines, which has sixteen materials, respectively located in2D,3D,4D,5D and6D chromosomes. Chromosome2D has four, chromosome3D has six, chromosome4D has two, chromosome5D has one, and chromosome6D has three.