Construction Of RIL Genetic Map By Soybean High Oil×High Protein And QTL Analysis Of Important Agronomic Traits

Presently,One of the most important attempts in soybean genome research is to construct populations with large contents and facilities to locate special important agronomic traits.A cross of Jiyu47x Liaodoul6 is made,then selfed for 7 generation by single seed descent method to construct RIL populations.75 pairs of SSR primers that are polymorphism are selected from 200 pairs of SSR primers which cover almost the whole soybean genome,SSR markers are used in constructing genetic map and tagging QTL of some agronomic traits,it may be established the foundation for the follow up genetic map saturated,the genetic information about soybean agronomic related traits would provide important theoretical guide for the high-yield and high-quality soybean breeding.Results of these studies are as follows:The 7^th generation of RIL population is constructed contained 120 lines.A genetic map based on SSR markers were constructed with this population consisting of 110 lines.It covers 18 linkage groups with 74 simple sequence repeat(SSR)markers,The total length of the map is 1479.5 cM and the average distance is 27.1 cM.The number of markers on each group ranges from 3 to 7,and the length of each group ranges from 30 to 145.4 cM.The longest average distance is 36.0 cM,on group c10(F),The nearest average distance is 14.6 cM,on group c12(â… ),there are 47 intervals longer than 20cM.It is easy to compare this map to soybean public integrated genetic map for most markers in this map are SSRs,18 linkage groups of the map fit the "Consensus Linkage Map" well in the order of arrangement of the SSR markers.QTL tagging and analysis of 12 soybean agronomic traits by method of composite interval mappling is pursued with our constructed map,a total of 11 QTLs for 9 agr onomic related traits under 8 different linkage groups were identified.Most of the traits are clustered,Some QTL are mapped to the same linkage group.Among the QTL we get,there are 4 QTL which can explain the total variation more than 10%,2 QTL which can explain the total variation more than 20%.Of the QTL associated to seeds per plant,Satt372 can explain 61.78%total variation,these QTL are proposed as main effective genes and further fine mapping will be carried out.It's the basic for map-based cloning.