Genetic analysis and gene fine mapping of a rolling leaf mutant (rl11(t)) in rice (Oryza sativa L.)

The exploration of new genes controlling rice leaf shape is an important foundation for rice functional genomics and plant architecture improvement. In the present study, we identified a rolling leaf mutant from indica variety Yuefeng B, named rl(11(t)), which exhibited reduced plant height, rolling and narrow leaves. Leaves in rl(11(t)) mutant showed abnormal number and morphology of veins compared with those in wild type plants. In addition, rl(11(t)) mutant was less sensitive to the inhibitory effect of auxin than the wild type. Genetic analysis suggested that the mutant was controlled by a single recessive gene. Gene Rl(11(t)) was initially mapped between SSR markers RM6089 and RM124 on chromosome 4. Thirty-two new STS markers around the Rl(11(t)) region were developed for fine mapping. A physical map encompassing the Rl(11(t)) locus was constructed and the target gene was finally delimited to a 31.6 kb window between STS4-25 and STS4-26 on BAC AL606645. This provides useful information for cloning of Rl(11(t)) gene.