The Analysis Base On The SSR And The Combining Ability Of The Inbred Generation From The Cross Of Local Maize Germplasm And Its Derived Lines

This experiment was basis of inbred line Wo30 and the 8 recombination system which were derived from the crossing of Worihuang and Wo30 and 90 crosses from incomplete diallel cross.Based on the field observation data,combining ability analysis and SSR Molecular Markers were used to study the effect of recombination by local maize germplasm and its selections.The results showed that:1.There was a large diversities on mainly trait of Wo30 and the 8 reconstitute lines, in which the yield coefficient variation was the biggest at 48.56%,the ear diameter coefficient variation was the smallest at 11.05%,the average coefficient variation was 20.94%.The result of genotype significance test of difference between Wo30 and the 8 reconstitute lines showed that there were significant differences between 7 traits of the materials except the 100-kernel weight,which was revealed there was a obvious variation according the recommbination.The result of multiple comparison betweenWo30 and the 8 reconstitute lines showed that,A3 was significantly higher than Wo30,A5 and A8 was extremely significantly lower than Wo30,the rest reconstitute lines were not markly;the ear height of A2 was extremely significantly higher than Wo30,A1,A5 and A6 were extremely significantly lower than Wo30,the rest reconstitute lines were not markly;the ear length of A3,A5,A6,A7 and A8 were extremely significantly smaller than Wo30,A1 was ignificantly smaller than Wo30,the rest one were not markly;the ear diameter of A1 and A4 were extremely significantly larger than Wo30,A3 and A6 were significantly larger than Wo30,the rest part of the inbred lines were not markly;The axis diameter of A1,A4,A5 and A8 were extremely significantly larger than Wo30,A3 was sinificantly larger than Wo30,the rest one were not markly;The rows per ear of A1,A3,and A4 were extremely significantly larger than Wo30,the rest one were not markly;The plant weight of A3 was significantly higher than Wo30,A5,A6 and A8 were significantly or extremely significantly lower than Wo30.The result indicated that there was a obvious variation among the Wo30 and the 8 reconstitute lines2.The analysis of GCA variance indicated that,all the observed traits in GCA and SCA of Worihuang and Wo30 and 90 crosses,was significant except for the kernel depth.According to the GCA of plant weight and yield trait,A1,A2 and A8 showed a better performance in GCA,in which A1 showed a good performance in ear length,kenerl depth,rows per ear and kernels per row but the GCA of 100-kenerl weight performed worse;A2 showed a good performance in ear length,rows per ear,kernels per row, Sterile length and 100-kenerl weight,but the ear weight and kenerl depth performed worse;A8 showed a good performance in ear length,ear diameter,kenerl depth,rows per ear,Shelling percentage,100-kenerl weight,ear weight and ear diameter but the disadvantage was that the Ear height and Shelling percentage were negative at a significance level. Judging by the SCA of plant weight the top three commbination of SCA effect size were CH10×A3 21.72,CH29×A8 21.71,CH14×A4 18.80;the lowest effect size of SCA commbinnations was CH14×A8 -33.23.19 combinations with superiority over CK 20% in yield/plant of the top three were CH29×A8,CH14×A4 and CH20×A4,the frequency of occurences in the 19 combinations,A4 was 5,A3,A1,A2,A7,A8 was 2,A6 was 1.3.SSR molecular makers were used to study the effect of recombination by Local maize germplasm and its selections,thirty-one pairs of SSR primer distributed on all the 10 chromosomes of maize produced stable bands and 85 alleles were detected among the 9 inbred lines including the 8 recombinant inbred lines and Wo30.The average number of alleles per locus was 2.74 with a rang from 2 to 5.The values of polymorphism information content(PIC) for each SSR locus varied from 0.20 to 0.77 with an average of 0.47.The values of mark index for each SSR locus varied from 0.40～3.85,with an average of 1.41.4.The analysis based on the SSR result showed that,there was a comparatively large difference in the genotype of Wo30 and the 8 reconstitute line,most of the materials were detected 1-2 bands by SSR,some of them were detected 3 bands,few of them were detected nothing.Different genotypes from Wo30 were detected by all the 31 primer s,different numbers of genotype were detected by different primers.The highest record was that 5 genotypes were detected by one primer,thelowest was 2 genotypes were detected by one primer.The primer with a higher Alleles,PIC and MI detected more genotype,the result indicated that,a higher Alleles,PIC and MI led to good result. 5.To count the percentage of uniform genotype of Wo30 and the 8 reconstitute lines, the higher number was 87.5%,the lower number was 0,it also indicated that there was a difference between Wo30 and the 8 reconstitute line.to classify the uniform genotype by SSR local site and caculate the average value of uniform genotype at each chromosome,the result showed that chromosome 9 had the highest value of 75%,the chromosome 1 had the lowest value of 16.67%,which was far below the totall average value.Thereafter,the gene reconstitute may be mainly on the chromosome 1.According to the result of SSR,the genetic similarity of SSR maker pattern among Wo30 and the 8 reconstitute lines ranged from 0.47 to 0.84 with an average of 0.61,both the mean value and amplitude of variation were large.The cluster analysis showed that Wo30 and the 8 reconstitute line could be classified into 3 groups.The GroupⅠconsisted of A1,A2,A3,A5 and Wo30,the GroupⅡconsisted of A4 and A8,the GroupⅢincluded A6 and A7,respectively.6.Part of the reconstitute lines derived from the cross of Wo30 and elite plant of Worihuang were superior to the agronomic and maily yeild trait,it showed a good effection of the method of deriving inbred lins from the cross of Wo30 and Worihuang. Therefore the method was able to generate new genotypes or create new mutation,if the orthoselecfion was used,can be derived more inbred lines with excellent genotype,and achieve the aim of excavatting the elite gene in the local maize germplasm.