转化双价防卫基因获得抗纹枯病水稻

Transgenic Rice with Double Defense Genes Exhibiting Resistance to Sheath Blight (Rhizoctonia solani Kuhn.)

将水稻几丁质酶基因 (RCH10 )和苜蓿 β 1,3 葡聚糖酶基因 (AGLU)串联构建于一个表达质粒 pZ10 0 ,经农杆菌介导法转化粳稻台北 30 9,获得 15个阳性独立转化子。T1代植株经Southern检测 ,表明外源基因已整合到了水稻基因组 ;经Northern检测 ,表明外源基因在RNA水平表达 ,在株系间有差异 ,2个酶基因的表达水平类似。T1代植株经纹枯病病菌接种鉴定 ,表明各株系对纹枯病具有不同的抗性 ,且抗病能力与 2个外源基因的RNA表达水平有剂量关系 ,并获得了 2个酶基因高表达且对纹枯病具有较高抗性的T1株系 ,可作为进一步进行分子育种的材料。

The rice chitinase gene ( RCH10 ) and the alfalfa β-1,3-glucanase gene ( AGLU ) were tandem-inserted into the transformation vector pBI101 under the expression control of the 35S promoter and 35S enhancer, resulting in the plasmid pZ100. pZ100 was transformed into rice ( Oryza sativa . L. ssp. japonica . cv. Taipei 309) by Agrobacterium -mediated transformation. Fifteen independent transformants were obtained and confirmed by PCR and Southern blot analysis (Fig.2-4). Northern blotting analysis with the RCH10 and AGLU probes revealed expression variation among these transformants on transcription level (Fig.5). Similar expression patterns were observed for both RCH10 and AGLU transcripts from the same individuals. Disease resistance to rice sheath blight caused by R. solani was evaluated in the transgenic plants (Fig.6). It was demonstrated that the transgenic rice exhibited higher resistance to R. solani than the wild type plants, and resistance levels were related to expression levels of the transgene, showing dose-dependence. Two independent lines with high disease resistance as well as high expression levels of RCH10 and AGLU were selected for the further studies and molecular breeding for sheath blight resistance.