Studies On Genetic Diversity Of Rice Using Molecular Markers

The cultivated rice (Oryza sativa L.) is one of the most important crop in the world, and development of hybrid rice is the only way to ensure Chinese foodstuff security. Having made great progress, rice breeding with three-line and two-line methods has made great attribution to Chinese grain product. However, with the population increasing as long as the plowland decreasing, it becomes more and more agent to increase yield of grain. However, the yield-increasing extent in mass product of rice has not made a breakthrough during past years, because that the genetic diversity of Chinese rice, specially those major parents, is not rich enough. Therefore, innovating rice germplasm and richening the genetic diversity of parents of hybrid rice has been the major orientation of hybrid rice research. Accordingly, evaluating the genetic diversity of nuclear DNA and cytoplasmic DNA of various types of rice at the molecular level undoubtedly is very important to help detect and utilize the favorable genes of diversified rice germplasm and consequently breed hybrid rice parents with rich genetic diversity to promote persistently high yield of hybrid rice.The genetic polymorphism of nuclear, chloroplast and mitochondrial DNA of common wild rice (CWR) and cultivated rice was detected using molecular markers. The main results on genetic diversity of rice were as follows: 1. Genetic polymorphism of rice nuclear DNASixteen ISSR primers which were able to generated clear and highly polymorphic bands were screened from 43 primers and employed in the...