QTL Mapping Of Important Agronomic Traits Of Wheat

Many important agronomic traits of wheat are qanutitative traits, such as yield's component facters, growth period and quanlity and so on. For the complexity of genome of hexaploid wheat, construction of molecular marker genetic linkage maps of wheat and QTL analysis are far behind of other cereal crops, like rice, maize and so on. In this study, a genetic linkage map was constructed with higher density of molecular markers and 6 important agronomic traits of wheat were QTL mapped. The main results are as follows:1. 185 F7 recombinant inbred lines of the cross between commen wheat'Nongda015'and'Fuzguang30'were mapping population. 1,631pair of SSR, EST-SSR and AFLP- SCAR primers were selected to analysis the polymorphism between parents. 466 showed polymorphism, primer polymorphic ratio was 28.57%. 338 of 466 polymorphic primers amplified 394 loci with clear and stable DNA bands. The genetype of these 394 loci were analysised by software QGAstation1.0 and drawn by CAOLEFGL. The skeleton map consisted of 359 loci (312 SSR loci, 32EST-SSR loci and 15 SCAR loci) distributed on 21 chromosomes of wheat with a total length of 3,690.19 cM and average distance of 10.28 cM between adjacentmarkers. 21 loci of SCAR and EST-SSR markers developed by BETRCHW in recent years as well 48 non-located SSR and EST-SSR markers were mapped for the first time on the current map.2. The QTL analysis was performed with the software WinQTLcart2.0. A total of 20 QTLs for thousand-kernel weight, spike length, kernel number per spike, spikelet number per spike, effective spike per plant and plant height with LOD thresholds of 2.5 were detected. These QTLs were located on 14 chromosomes except that 1D, 2A, 3D, 4D, 5D and 6B. 11 of 20 QTL mapped in this study were major QTLs. 5 QTLs for thousand -kernel weight distributed on 1A, 2B, 6A and 7D chromosomes, the tatol contribution ratio was 83.97%; 4 QTLs for spike length were located on 1B, 4A and 6D chromosomes, the tatol contribution ratio is 45.47 %; 2 QTLs of kernel number per spike were located on 3B and 5B chromosomes, the tatol contribution ratio is 21.91%; 2 QTLs of spikelet number per spiker were located on 2D and 5A chromosomes, the tatol contribution ratio is 22.42%; 4 QTLs of effective spike per plant were located on 1B, 3A, 4B and 7B chromosomes, the total contribution ratio is 42.99%; 3 QTLs of plant height were located on 1B and 3B chromosomes, the tatol contribution ratio is 46.44%.