Analysis Of Genetic Distance And Yield Heterosis In The Elete Parental Lines Of Ron-you Sierial Hybrid Rapeseed In Brasscia Nups L.

Breeding for heterosis is based on the genetic difference between the parents of hybrids in crops. Heterosis is currently extensively used to enhance yield and for improvement of quality in main crops. Mature development of molecular markers are a platform for the selection of strong advantage of cross combinations and The heterosis provide.In the present study,60 Ron you elite Brassica napuyparental lineswere selected for tests, and constructed Ron-you elite Brassica napus parents the first cluster analysis diagram by SSR molecular markers, order to find out the genetic diversity of Ron you elite Brassica napus Parents lines; a 4×15 diallel cross design was used with 4 Brassica napus male sterility(GMS) lines and 15 Brassica napus restorer, and 60 hybrids were obtained, and investigation harvest time yield, analysis correlation between genetic distance(GD) based on SSR molecular markers and yield heterosis of Brassica napus, assist breeding next Ron you variety.The main topics of this thesis are as follows.1.Picked out 102 pairs of polymorphic SSR primers from 400 SSR primers, a total of 452 bands were amplified, and Polymorphism bands is 338,39 pairs of polymorphic SSR primers linkage of Brassica napus chromosomes, the ratio of polymorphism primers and polymorphism bands respectively is 25.5% and 74.7%;each pair polymorphism primers detected 1 between 11 alleles,3.3 alleles on average; the PIC range of each marker loci is 0.21between0.91,0.69 on average,90 pairs of polymorphic SSR primers PIC>0.5,the ratio of this is 88.2%;Na:1.873、 Ne:1.437、He:0.256、I:0.441.2. Clustering analysis by SSR molecular markers indicated 60 lines could be divided into two groups(A and B) at GS threshold value of 0.453,E9 was independence existed in A group,clutering analysis by SSR molecular markers indicated B groups could be divided into thirteen sub-groups(B 1 to B13),number of three nuclear male sterility lines at B2 sub-group, number of seven cytoplasmic male sterility lines at B6 sub-group, number of fifty restorer lines at all sub-group except B2 sub-group and B6 sub-group, among all sub-groups exists large genetic differences. Association Characterization Matrix and genetic similarity matrix was significantly correlated, Correlation coefficient 0.757 at cophenetic text. PCA analysis could override clustering analysis of seven sub-groups and eleven pedigree groups, explained clustering analysis had high conjunction with parental origin, and could be distinguished from special materials.3. Genetic distance (GD) range of nuclear male sterility lines between rest orer lines is 0.3964 to 0.6084,0.4985 on average; genetic distance(GD) range o f cytoplasmic male sterility lines between restorer lines is 0.3882 to 0.6561.0.5 2 on average.Genetic distance was significantly correlated with yield heterosis.r =0.262*.R2=0.069<0.1,cubic regression curve showing the control with the adv antage after the first rise and then fall upward trend appears to increase the ge netic distance.