Abstract: Leaf is a main organ for plant photosynthesis. Fine leaf shape is beneficial for building an ideal plant type and improving the efficiency of photosynthesis. In order to study the molecular mechanism of leaf morphogenesis, an half rolled leaf mutant rlm1 was discovered from the rice T-DNA insertion mutant library. The mature leaf of rlm1 mutant involuted along midrib, and finally become half cylinder. The leaf rolling index was 0.64, leaf erect parameter was 95, and the mutant photosynthesis efficiency was higher than the wild one. The mutation site of rlm1 was verified by mapping at the 1st intron of gene LOC_Os03g06654, which encoded flavin-containing monooxygenase. RT-PCR expresion and analysis indicated that LOC_Os03g06654 was inactive completely by T-DNA insertion. The gene was another allele of the reported rice curly leaf gene OsCOW1(Constitutively Wilted 1). Due to the good agronomic property of rlm1, it could be used to conduct high photosynthetic breeding practice.

Key words: rice(Oryza sativa L.), rolled leaf mutant, T-DNA, photosynthesis efficiency

摘要： 叶片是植物光合作用的主要场所，优良的叶片形态有利于塑造理想的株型，提高光合效率。为了研究叶片形态建成的分子机制，自水稻T-DNA插入突变体库中筛选获得1个叶片半卷曲的卷叶突变体(roll leaf mutant，命名为rlm1)，突变体rlm1主要特征为成熟叶片沿中脉向内卷，叶片最终卷成直立半圆筒状，叶片卷曲度达0.64，叶片直立参数达95，且光合效率显著优于野生型。通过图位克隆技术，确定突变体rlm1突变位点位于LOC_Os03g06654基因的第1个内含子，LOC_Os03g06654基因编码黄素单氧化酶（flavin-containing monooxygenase），RT-PCR表达分析表明LOC_Os03g06654基因因T-DNA插入而导致完全失活。该基因与已报道的水稻卷叶基因OsCOW1（Constitutively Wilted 1）为等位基因，而且突变体rlm1所表现的农艺性状均佳，可期待利用该突变体进行高光合的育种实践。

关键词: 水稻(Oryza sativa L.), 卷叶突变体, T-DNA, 光合效率