Genetic Analysis And Fine Mapping Of A Semi-dominant Rolling Leaf Mutant In Rice(Oryza Sativa L.)

Rice is one of the most important cereal crops and play a decisive role in our country. With the completion of sequencing rice genome as well as one of the most important model organisms and promotion of the basic study. Therefor, the leaf of rice play an important role in photosynthesis and increase yield is of great significance. We identified a semi-dominant rolled leaf(srl2) mutant from the mutant library built. In this study, we performed the genetic analysis and adopt map-based cloning method to complete the gene mapping of SRL2, The main results were as follows:1. Ml generation of srl2mutant performed semi-curled leaf, but in M2generation showed three types:extremely rolling leaf, semi-curled leaf and flat leaf. srl2mutant was crossed to three indica breeds, the Fl plant was of semi-curled leaf and the ratio of extremely rolling leaf plant to semi-curled leaf plant to flat leaf plant in F2poputation fitted1:2:1, genentic analysis show that the curly mutant was controlled by a single semi-dominant gene.2. Flag leaf length and width between srl2mutant and wild type have great difference through investigate the agronomic trait. Though the leaf of mutant had extremely rolling leaf, the thousand seed weight and number of grains per ear of mutant as well as widetype, on the contray, the tiller number and primary branch were more than wildtype significantly.3. Through the drought simulated experiment, the length of root and root hair number more in srl2mutant than wildtype.4. Anatomical and histological analysis showed that the number of vesicle parenchymatous cells in the srl2mutant increased and lead to the leaf curly, in addition, the volume of air space become bigger,it is possiblely cause the mutant costa swollen, narrow leaf width.5. Map-base cloning method was used to map the gene,SRL2gene finally fine delimited in a52.09kb on the chromosome4,with seven open reading frames in this region. Through the sequencing,we found a base group make a change in zinc finger domain,lead to change the amino acid and phenotype.