拟南芥花期基因转化烟草及其早花反应特性研究

为探讨花期基因对烟草开花早晚的影响及其在加快育种进程中的利用价值,采用RT-PCR方法从拟南芥克隆获得花期基因(FT),经过测序分析、酶切鉴定后连接到植物表达载体P22上,构建植物重组载体P22-FT。通过农杆菌介导,将FT基因转入烤烟品种Coker 371 gold后获得了26株阳性植株。研究结果表明,FT基因对烤烟品种Coker 371 gold的外观形态和花期具有较大的影响;与未转基因对照比较,FT阳性植株平均叶片数少15~16片,平均株高矮80 cm,现蕾时间提前了75 d左右。通过阳性植株自交分离群体及阳性植株与对照植株的杂交分离群体的鉴定选择,获得了单拷贝FT基因的2个阳性植株。早花基因转化烟草可以有效诱导烟草早花,缩短烟草生育期一半时间,单拷贝可分离早花植株在加快烟草育种进程中具有重要利用价值。

Study on Transgenic Arabidopsis Flowering Gene FT into Tobacco and Its Early Blooming Properties

To explore the effect of Flowering Locus T (FT) gene on the flowering of tobacco and stimulate its utility in tobacco breeding. FT gene was cloned by RT-PCR from Arabidopsis. After confirmation by sequencing and digestion, the fragment with proper digested sites was inserted into plant expression vector P22, and the expression vector FT-P22 was constructed. Then FT gene was introduced into Coker371 gold tobacco genome by Agrobacterium-mediated transformation, and 26 positive clones obtained. The result shows that the FT gene exhibited more influence on morphology and flowering of flue-cured tobacco variety Coker371 gold than wild type. The average leaf number of transgenic plant was less 15-16 pieces than control, their average height shorted 80 cm, and their budding time was ahead of about 75 days. By using the self-fertilization segregation population of positive plant and the hybridization separation group between positive plants and the control plants, we had got two positive plants with single copy of the FT gene. The transgenic FT tobacco could induce the early blossoming and short the half time of breeding cycle, the single copy segregation plant exhibited the very important utility value in speeding up the breeding process of tobacco.