Genetic Analysis And Fine Mapping Of Glumous Palea Mutation Pd1 From Rice(Oryza Sativa L.)

As one of the popular food for human beings, the glume flower development results of rice influences its yield and quality. Consequently, the research of stamen,pistil,lemma and palea genes for rice flower development especially related to yield,guality is with very important practical significance.The floral organ of rice, which belongs to gramineae monocot, includes 1 lemma,1 palea,2 lodicules,6 stamen and 1 pistil (1 ovary and 2 stigmas), besides, the basal of floral organ has 2 degenerative glumes and 2 protective glumes.Compared to the research of floral organ development model of the dicot, the research of floral organ development model of monocot is backward. Rresearchers are screeneing the rice's genomic library and cDNA library by the conserved sequence of monocot development genes, and have got lots of MADS-box genes. However, because of lacking of points of junction for characters, the exact function of majority genes are not sure. Using floral organ mutations in research of genes for flower development is more effective.In the Y ray irradiation mutagenic treatment progenies of rice varieties 93-11, we found 1 mutation with ateliosis palea and its mutant character is genetic stability in the different environmental multiple generational self-cross planting. The research has done genetic analysis of mutant character of the mutation, anatomical observation of its flower structure, fine mapping of related gene, and prediction of candidate genes, main results are as follows:(1) Anatomical observation floral structure:except 1 lemma,2 lodicules and 1 pistil of the normal rice glume flower, the mutation glume flower has 1 dysplasia bladed palea, which causatives the flower bending; the number of stamen decreased to 4 only; pollen fertility,seed setting rate and 1000-grain weight decreased significantly.(2) Genetic analysis of rice glume palea mutation:in the heading stage, we have done observation and inverstigation of F1/F2 population which from pd1 and Suyunuo. As a result, the flowers of F1 population have normal phenotype, so it's recessive phenotype. Afterχ2 testing(x2c<x20.05=3.84) of the F2 population characters investigation, the proportion for the number of normal plants and the palea development mutation conforms to segregation ratio 3:1, which shows that the mutant character is being controlled by 1 pair recessive genes.(3) Fine mapping of related gene:by based cloning, using F2 population from pd1 and Suyunuo; F2 population and F3 population from pd1 and Nipponbare,Reyan, we have fine mapped the related gene PD1 in a 69Kb interval between RM11239 and RM11245 under the centromere of Chrl.(4)Prediction of candidate genes of PD1:after searching the genomic sequence, there are 10 ORFs in the target interval,6 of them have expression information. LOC_Os01g40120 only express in flower, and has domain LYAR-type C2HC zinc finger. So, LOC_Os01g40120 has been determined as the first candidate gene for further functional research.