根癌农杆菌介导的水稻转化及转基因R_1代植株表型特征

Agrobacterium mediated Transformation of Rice and the Phenotypic Characteristics of the Transgenic R_1 Plants

用根癌农杆菌介导的方法对２ 个粳稻品种和４ 个籼稻品种进行了转化。粳稻成熟胚和籼稻幼胚来源的愈伤组织用携带质粒ｐＧＩＨ 的农杆菌ＥＨＡ１０１ 感染，对所有品种均获得较高的愈伤转化频率（２０．８３ ％ ～６２ ．３２ ％ ） 。粳稻“申香粳４ 号”植株转化频率为１７ ．３９ ％ ，“秋丰”为９ ．２１％ 。４ 个品种籼稻中仅“超丰早１ 号”获得１ 株转化植株。Ｓｏｕｔｈｅｒｎ 杂交分析、ＧＵＳ 染色、ＴＤＮＡ 整合边界序列分析等结果表明外源基因整合入植物基因组中。对Ｒ１ 代分析结果表明外源基因能遗传给后代，大多数株系的分离比符合３∶１ ，也有少数株系分离比异常。对转基因Ｒ１ 代水稻植株表型特征分析结果显示转化植株株高下降，每株分蘖数减少，每株籽粒数明显减少，部分植株播种至开花所需时间延迟。

Genetic transformation mediated by Agrobacterium tumeficiens has been applied to two japonica varieties and four indica varieties of rice(Oryza sativa L.). The frequencies of transgenic calli are high(20.83%～ 62.32 %) for both the japonica and indica varieties tested(Table 1). The frequency of transgenic plants in japonica variety “Shenxiangjing No.4”was 17.39 %,while that in japonica variety “Qiufeng” was 9.21%. Among the 4 indica varieties, only 1 transgenic plant was obtained in “Chaofengzao No.1” (Table 2). Integration of foreign genes into the genome of transgenic plants was confirmed by Southern analysis(Fig.2), GUS assay(Plate I b,e) and boundary sequence analysis of T DNA in transgenic rice plant(Fig.3). Foreign genes were inherited and expressed in R 1 progeny(Table 3,Fig.4). Mendelian 3∶1 segregation ratio was observed in most R 1 progeny(Table 3). Transgenic R 1 plants showed lower plant height, reduced number of tillers per plant and reduced number of grains per plant(Table 4). Some transgenic plants took longer time from sowing to flowering.