防龋用转基因番茄生态安全性的评价研究

Evaluation of the ecological safety of pacA-ctxB and pacP-ctxB gene transgenic tomato

目的:观察本课题组培育的防龋用转基因番茄中外源目的基因pacA-ctxB、pacP-ctxB是否通过花粉和根系分泌物造成基因漂移,初步探讨该转基因番茄防龋疫苗的生态安全性。方法:田间种植转基因番茄,距转基因植株的边缘0.5、1、3、10 m处种植非转基因对照番茄作为基因漂移的受体,开花期自由授粉,结果期在距离转基因番茄植株边缘0.5、1、3、10 m处,各随机收取10株基因漂移受体株番茄果实,采集种子实验室培养,幼苗期采集叶片提取总DNA,用PCR法进行花粉漂移的检测。在转基因番茄植株根部的东、南、西、北方向各取一份土壤样本,提取土壤总DNA,用PCR法进行外源基因根系漂移的检测。结果:距离转基因番茄0.5 m处的2株非转基因番茄第二代植株经PCR检测发现有外源目的基因pacA-ctxB、pacP-ctxB,分别在10株含pacA-ctxB、pacP-ctxB转基因番茄的根际土壤总DNA中未扩增出相应的目的片段。结论:转基因番茄中外源基因pacA-ctxB、pacP-ctxB在田间可通过花粉造成基因漂移,但未观察到该外源基因通过根系分泌物漂移到转基因植株根际的土壤中。

AIM：To observe whether the exogenous gene pacA-ctxB or pacP-ctxB of the transgenic tomato can cause gene flow by pollen and root exudates and to explore the ecological safety of the transgenic tomato.METHODS：The transgenic tomato plants were planted in the field.Non-transgenic tomato plants were grown at 0.5m,1m,3m and 10m away from the transgenic tomato as drift acceptor.All tomatoes were pollinated randomly in the efflorescence.Tomato fruits were collected from 10 plants stochastically and cultivated in the lab.Finally the blades of seeding stage were detected by PCR.Soil samples from four directions（east,south,west and north） of transgenic tomato roots were collected and edaphic DNA was detected by PCR.RESULTS：Exogenous genes were found by PCR in the second generation of 2 non-transgenic tomatoes which was 0.5m away from the transgenic plants.pacA-ctxB and pacP-ctxB genes were not detected in all the soil samples.CONCLUSION：Exogenous genes pacA-ctxB and pacP-ctxB in the field can drift by gene flow through pollen,but the exogenous gene does not drift through the root exudates of the transgenic plants to the rhizosphere soil.