中文摘要：

基因表达调控是水稻化感作用形成的重要基础。本研究对化感水稻P1312777（Oryza sativaL．）的OsMYB（CT82953）基因分别进行过表达（overexpression，OE）和RNA干扰（RNAi），再与稗草（Echinochloa crusgalli，BYG）共培养，以野生型P1312777为对照。结果发现，与稗草共培养下CT829537-OEPl312777的酚类代谢关键酶基因表达上调，根系及其水培液中的总酚酸浓度增加，抑草能力增强；相同处理下CT829537-RNAiPl312777则相反，其酚类代谢关键酶基因较野生型植株表达下调，总酚酸浓度降低，抑草能力下降。这表明OsMYB（CT829537）通过调节化感水稻的酚酸类物质合成进而影响其抑草能力。

英文摘要：

Regulation of gene expression is a vital process in the formation of rice allelopathy. In this study, allelopathic rice PI312777 （Oryza sativa L.） was modified by RNA interference （RNAi） and overexpression（OE） technologies to inhibit or en- hance gene expression of OsMYB （CT829537） in PI312777 respectively. The results showed that up-regulation of phenolic syn- thesis related genes was found in CT829537-OE transgenic PI312777 co-cultured with bamyardgrass （BYG）, compared with that in wild type. However, the reverse was true in the CT829537-RNAi transgenic PI312777. Up-regulation of the gene expression in CT82953 7-OE transgenic PI312777 increased phenolic acids contents in rice root and root exudates, which led to enhance allelo- pathic inhibition on bamyardgrass. In contrast, decreases of phenolic acids contents and weed inhibition were found in CT829537-RNAi transgenic PI312777. These results implied that CT829537 is responsible for regulating phenolic synthesis in allelopathic rice PI312777 and then enhances allelopathic inhibition on weeds.