Genetic Analysis Of Main Agronomic Traits In F₂ Population In Rice Baodali ?Oryza Sativa L.Ssp Indica? And Aigela ?Oryza Satiza L.Ssp Japonica?

Rice is an important food crop,yield improving always be an important goal of rice genetic breeding and cultivation.Good quality traits can be integrated into same rice variety by reforming the rice plant type,leaf type,spike type and grain type,that not only can improve the yield of rice,also can improve the disease resistance of rice and rice quality.To better understand the genetic characteristics of 12 important traits(plant height,flag leaf length and width,panicle length,primary and secondary branch number,total spikelet grain number,seed setting rate,grain length and width,thousand grain weight,tomentum rate of grain)in rice,variety Baodali(indica)and variety Aigela(Japonica)were chose as the parental lines for hybridization,and F2 population were bulid to locate the QTLs,combined with the use of molecular markers and phenotypic analysis.The results summarized as follows:1.This study selected 100 molecular markers,which distribute on the 12 chromosomes evenly.We built the molecular linkage map total genetic distance 1732.31cM,and the average genetic distance is 17.31cM.We detected a total of 22 main effect QTL locus,2 plant height QTLs,5 flag leaf length and width QTLs,6 panicle traits QTLs,9 grain traits QTLs.In these locus,the LOD value of qPHl,qPH7,qPL7,qFLL7.1,qNSB7,qSNP7,qGL2.1,qGL2.2 were not less than 10.The new locus qPH7,qPL2,qPL7,qSSR6,qNPB7,qNSB7,qFLL7.1,qFLL7.2,qFLW7 and qDGT2.2.The F2 population exists major QTLs on the chromosome 7,those QTLs can control plant height,flag leaf length and width,panicle length,primary and secondary branch number,total spike grain number,and these seven QTL locus are in 2.1Mb range of A80 to A83,whether there is a multiple-effect gene need to be verified by more generation.3.A plant length QTL loci qPH1 were located on chromosome 1 in F2 population,according to the report,this range exists gene sd-1,which can control the height of plant.There also a major plant height QTL loci qPH7 be located on chromosome 7,and the 4Mb upstream of this loci exist a multiple-effect gene Ghd7,because this is far between qPH7 and Ghd7,a preliminary deduction is that qPH7 is a new major QTL for plant height.4.Grain length,grain width,and thousand seed weight QTL locus on chromosome 2 near the centromere position were located in F2 population.One report indicated in this site there exists a gene GS2,the loci was speculated as GS2.