Preliminary Mapping Of The Rice Erect Leaf Gene From Peiai 64S

Rice is one of the most important grain crops in China as well as in the world. Leaf morphology is an important part of rice plant type breeding, changes of which directly affect the efficiency of photosynthesis, normal growth and development of plant, even the yield of rice. In recent years, with the rapid development of molecular genetics and the completion of rice genome sequencing, the combining of molecular genetics techniques and traditional breeding method has become an important way to research the growth and development characteristics of rice. Erect leaf trait is an important morphological index of rice super high yield breeding, therefore understanding the genetic development of erect leaf trait is important to remold rice ideotype and increase production. In this research, by use of rice varieties Peiai 64S with erect leaf as female parent, IR841 with drooping blade as male parent and their hybrid offspring F2 populations as genetic mapping population, the morphological observation, genetic analysis, cytological observation and gene mapping were carried out. The main results were summarized as follow:1. All the leaves of F1 plants were erect leaves, while the F2 plants showed phenotypic segregation with erect leaves, intermediate leaves and drooping leaves. The ratio of these three phenotypes in F2 population was 9:6:1, consistent with the ratio of Mendelian inheritance. The results of genetic analysis showed that the target trait was a qualitative trait controlled by two dominant genes with the cumulative effect.2. The cytological observation showed that the midrib from the IR841 flag leaf had less the adaxial vascular bundles and the parenchymal cells between two cavities existing the central region of the midrib than those of female parent Peiai 64S.3. Combining map-based cloning with BSA method, one target gene was mapped between RM318 and RM207 on chromosome 2 and genetic distances are 4.2 cM and 3.9 cM respectively.4. By Reduced-Representation Genome Sequencing, the target genes were delimited on the chromosomes 2 and 12, which include four regions with 82 candidate genes.