晚疫病由疫霉菌(Phytophthora infestans)引起,主要侵染番茄和马铃薯等茄科作物,造成巨大的经济损失。马铃薯已有5个抗晚疫病基因被克隆。为了研究已克隆的马铃薯抗晚疫病基因是否在番茄中起作用,将马铃薯的抗晚疫病基因R3a、R1和RB通过农杆菌介导法分别导入番茄品种Moneymaker中。筛选得到的再生植株经PCR检测结果表明,目的基因已整合入番茄基因组;转基因番茄离体叶片接种验证结果表明,接种马铃薯晚疫病菌株89148-9(即小种0),转基因番茄产生了抗病的过敏反应(HR反应)。为了验证转基因番茄是否对番茄晚疫病菌株产生抗性,用番茄晚疫病的主流小种和强致病力菌株共5个菌株接种转基因番茄植株,结果表明转R3a和R1基因的番茄对部分番茄晚疫病菌株能够产生抗性,RB转基因植株叶片对5个番茄晚疫病菌株均产生抗性。该研究为番茄抗晚疫病的基因工程育种开辟了新的途径。
Late blight, caused by the oomycete Phytophthora infestans (Mont.) de Bary, is a devastating disease of the two Solanaceous crops, tomato and potato, and caused serious economic loss. Potato late blight resistant genes R3a, R1 and RB were cloned recently. In order to determine whether these resistance genes have function in tomato plants, R3a, R1 and RB were transferred separately into tomato plants by Agrobacterium-mediated transformation method. The transformants showed hypersensitive response (HR) to 89148-9, the potato late blight isolate race 0. Transgenic tomato plants were also inoculated with 5 tomato late blight isolates, and the results demonstrated that R3a and R1 showed resistance to some tomato late blight isolates, while RB showed resistance to all 5 isolates. These results suggested that it be possible to use potato late blight resistance genes RB to protect tomato from late blight.