| Rice is one of the most important crops and major food for many people in the world In China, the yields of rice have increased greatly since the hybrid rice applied and super-rice researched. With the developing of modern agriculture and improving of the life level, rice varieties have request not only the high and stable yield but also better and full product quality. Aromatic rice is regarded as pearl in rice because of its good quality, flavor, faint scent and tastiness. Therefore, it's very important to study the genetic diversities and relations among the parents of the aroma rice which has provided the main materials for rice researchers. In this study, DNA polymorphism of 29aromatic rice varieties was analyzed by SSR markers.213 primers mapped on 12 chromosomes were amplified, in which the special primers of genetic differentiation were screened. Furthermore, heterosis of aromatic rice was predicted according to the pertinence of the genetic distance and heterosis. The results were summarized as follows: 1. Analysis of genetic variety in 29aromatic rice213 primers were used to detect differentiation in 29aromatic rice and 24 primers showed polymorphism. The results showed that higher polymorphism were mostly distributed on chromosome 7, 8 , 10 and 11, whose PIC could reach to 0.672 on chromosome 10; lower polymorphism on chromosome 9, whose PIC was only 0.120.A total of 71 alleles were detected using 24 SSR markers. The number of alleles per locus ranged between 2 (RM129, et al.) and 6 (RM304), with an average of 2.96 alleles per locus. The overall size of PCR products ranged from 110 to 250bp. The PIC changes form 0.120 (RM205) to 0.672 (RM304) and the average was 0.371. Distance analysis indicated that not only the PIC with the same allele locus was different but also the PIC and the number of allele locus were not uniform. From the above, we could conclude that the variety degrees of 29aromatic rice were higher and the genetic variety was also greatly bigger.Cluster analysis indicated that all of the materials could be divided into three kinds. The results of Cluster analysis were mostly accordance with aromatic rice varieties of the same lineage and were closely to the results of the genealogist analysis. So it showed that SSR makes could be used to make the genetic distance clear, to make sure the genetic differentiation and go on genealogist analysis.The results of the cluster analysis of the agriculture economic characters indicated that distance analysis and cluster analysis of phenotype traits were accordance with genealogist analysis in some degree, but the difference is very big. It is probably relate to the traitsselection, characters and environment. The above showed that it is difficult to make certain the genetic nature of rice germ-resources using phenotype traits clustering. And the clustering results have approved it. 2. Analysis of the relativity between genetic distance and heterosisThe results of relativity analysis of the yield and its composition factors showed that only 1000-kernel weight and kernels per row of the traits with theories yield and biology yield reached to significance. But valid ear and seed set rate didn't reach to significance. The experiments showed the kernels per row and the 1000-kernel weight played key roles in all kinds of composition factors of the yield. But that didn't mean that the function of the valid ear and seed set rate was unimportant, by contraries, both traits of the yield composition factors are very important. The relativity of yield just didn't reach to significance in this study.The relativity analysis of genetic distance and heterosis indicated that relativity coefficient was partial to small between SSR genetic distance and heterosis of four yield traits and didn't reach to significance. The results in the above experiments showed that genetic distance of the parents couldn't reflect the heterosis in the materials selected, namely, genetic distance had no directly relation to heterosis. So, SSR markers selected in this study coul...
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