Mapping The Gene Of Rice Short Photoperiod-Sensitive Genic Male Sterility With SSR Markers

As the restrict factors are exist in farmland and water resources,the yield increase in rice will mainly based on the increase of individuals yield in the future. The use of heterosis to raising the production of rice has played an important role. Following the great success of three-line hybrid rice technology,after years of study by researchers,the two-line hybrid rice technology has also tend to mature,and begin to used in large-scale rice production.The two-line hybrid rice is based on the technology of photo(thermo)sensitive male sterile rice. According to the fertility conversion reaction of light and temperature conditions of light and temperature-sensitive male sterile lines,it can be divided into three kinds:photo sensitive male sterile line,thermo sensitive male sterile line and photo-thermo interactive sensitive male sterile line. According to the fertility conversion reaction of light conditions,it can be divided into long day-light photo sensitive male sterile line and short day-light photo sensitive male sterile line.Now there are more basic and applied research in long day-light photo sensitive male sterile line,but very little physiological and genetic researchment are developed in short day-light photo sensitive male sterile line. We can see that now it is necessary to research and study the short day-light line,from this we can rich the basic theory of two-line hybrid rice and develop new kind of resource type. This study is to research the short photoperiod sensitive male sterile rice D52S,this kind of rice is absolutely fertile when it is long day light and sterile when short day light. So we can used it into two purposes when at suitable time.In this study,we use the materials of F2 generation which are made from D52S/Gui99 and D52S/Shuhui527,use pollen sterility as an quota,use the seed-setting rate as reference to analysis the genetic model of this gene. We use the SSR molecular markers and BSA method to find the nearest SSR markers of the sterile gene and to calculated the reorganization data between markers and the gene through maximum likelihood method. At last we should draw the genetic linkage map of D52S'sterile gene on the chromosome. Through this we can fine mapping and cloning the gene in the future,we can also use this result to study the relative gene of rice short photoperiod sensitive male sterile gene and use MAS to choice the new photoperiod sensitive male sterile materials.Major results are as follows:1.Identification of pollen sterility of F2 generation. From Sep 10th of 2008,at the condition that the D52S has began to turn to sterile,we began to identify the pollen sterility of F2 generation,and made two distribution chart of pollen sterility. It shows that the two F2 generation's pollen sterility data are mainly focus on two intervals:"0～5%" & " 80%～100%",generally presented as a bimodal distribution.2.Investigate the seed-setting rate of two F2 generation. By the end of October 2008, we began to investigate the seed-setting rate of two F2 generation as a reference indicator,and made two distribution chart of IV the seed-setting rate of two F2 generation. It shows that under natural growth conditions in the field,the data mainly focus on wo intervals:"0～10%"&"60%～100%",presented as a bimodal distribution.3.The genetic analysis of D52S'S sterile gene. According to the results of pollen fertility identification,we choice fertility data 5% as the line of fertile and sterile. It shows that:in F2 of D52S/Gui99,there have 164 fertile individuals and 50 sterile individuals; in F2 of D52S/Shuhui527,there have 252 fertile individuals and 76 sterile individuals. Chi-square test shows that the separation ratio of F and S are equal to 3:1.So we can make sure that the sterile gene are controlled by a main-effect sterile gene.4.Use SSR markers to map the sterile gene of D52S.In all totally 357 SSR markers, there have 124 markers showed polymorphism between D52S and Shuhui527. After construct DNA pools and used it to analysis the parents'polymorphism markers,we got 6 markes which are polymorphism between two pools. And then use this 6 markers to analysis all the 328 F2 individuals,the band data are used to construct the genetic map.We calculated the reorganization data between the markers and the gene through maximum likelihood method,and use Mapdraw software to draw the genetic map of the sterile gene on the chromosome. The results show that:the sterile gene is located on NO.10 chromosome,and the distence between the gene and SSR markers RM5271,RM244 are 5.3cM and 4.6cM respectively.