Abstract: Leaf is one of the most important photosynthetic organs and plays an important part in the productivity. We screened the rice leaf morphological variation mutants and isolated a curly leaf mutant（clf1）showing abaxial leaf rolling. The more bulliform cells numbers on leaf adaxial sides in clf1 mutnat were the main reason leading to leaves curling. Using Map-Based cloning methods,the site controlling CLF1 gene was mapped in chromosome2,tightly linking with two polymorphic markers（InDel51 and InDel57）. There were 44 genes in this region and we predicted LOC_OS02G45250 as the target gene by bioinformatics. We found that there were 20bp deletion in the sixth exon of LOC_OS02G45250 and the nucleotide deletion created a premature stop codon in the predicted coding region. The clf1 was another allele of the reported rice curly leaf gene Roc5（Rice outermost cell-specific gene5）,whose encoded transcription factor including GL2 homologous structure domain. Different from the oul1 mutant（loss-of-function in Roc5）,the clf1 was valuable for the production because of a better agricultural characters.

Key words: rice, clf1, map-based cloning