QTL Mapping Analysis Of Kongyu 131 Grain Type For Heilongjiang Rice Cultivar

Rice is of great significance to human beings,because rice is the staple food for half of the world’s people.Rice also is a ideal model plant for biology re-search.Rice grain length,grain width,grain thickness and L/W ratio are belong to the grain shape traits.and is a heavy play the decision of the grain size and appearance and eating quality properties.grain shape is one of the important elements of yield components.This makes them a hot trait in breeders’research.Positioning rice grain type QTL to find the main effect QTL,and then fine positioning is the prerequisite for the cloning of the gene.It has many theoretical values to improve rice quality and production.The experiments in the previous studies on the grain of QTL mapping and cloning of the Kong Yu131 and Zhen Shan97 derived containing 150 lines of F₂ generation for preliminary positioning test materials of grain type groups and their both linkage map including 140 SSR markers were used to map QTL controlling grain shape and fine mapping research.Detected a total of 30 QTLs related to grain shape traits,1,2,3,4,5,7,8,9,10 and 12 chromosomes.IncludingGL 11QTLs,GW 9 QTLs,GT 3 QTLs,L/W 7QTLs.And choose from grain length of detected QTL a LOD grain length ratio up to22.8%of the value of 10.8,QTL-qGL8-2 combined with 400 strain of F₃ generation group between chromosome 8 RM22780-RM22797 between 444.6 kb physical distance.At the same time choose from grain width of QTL detected a LOD value of8.46,the contribution rate is as high as 15.2%of the grain width QTL-qGW9 strain by480 F₃ generations group eventually will be located on chromosome 9 long arm RM215-RM24737 between 235.027 kb physical distance.The main results are as follows:1.Traits’identification values of grain length（GL）and length-width ratio（L/W）of KongYu131 is significantly lower than ZhenShan97,but significantly higher than ZhenShan97on the traits of grain width（GW）,grain thickness（GT）.KongYu131obviously displays the performance of short-wide-thick.Due to the recurrent parent influence KongYu131,most individuals in F₂ populations their traits’identification values of grain length,grain width and length-width ratio tends to KongYu1312.Correlation Analysis between traits by SPSS/EXP in F₂ populations shows that,Correlations between GL and GW was not significant,GL and L/W was significantly positively correlated,GW and L/W was significantly negatively correlated;GW and GT was significantly positively correlated.3.One genetic linkage maps including 140 SSR markers were constructed by Mapmaker/EXP3.0 and we were drawn according to the distance and sequence between the marks by ICIMapping4.0.One genetic linkage map was separately about 1669.6cM which covered the rice genome.The average distance between molecular markers was separately 11.9cM.4.Detected QTL by Mapmaker/QTL1.1 Detected a total of 30 QTLs related to grain shape traits,1,2,3,4,5,7,8,9,10 and 12 chromosomes.Including 11QTLs for GL,9 QTLs for GW,3 QTLs for GT,7 QTLs for L/W.qGL3、qGL8-2、qGW2-1、qGW9、qGT4、qL/W5-1、qL/W7-1.they are major QTLs controlling related trait.5.Choose from grain length of detected QTL a LOD grain length ratio up to 22.8%of the value of 10.8,QTL-qGL8-2 combined with 400 strain of F₃ generation group between chromosome 8 RM22780-RM22797 between 444.6kb physical distance.At the same time choose from grain width of QTL detected a LOD value of 8.46,the contribution rate is as high as 15.2%of the grain width QTL-qGW9 strain by 480 F₃generations group eventually will be located on chromosome 9 long arm RM215-RM-24737 between 235.027kb physical distance.