抗药性根瘤菌基因工程菌的构建与应用

CONSTRUCTION AND APPLICATION OF AN ANTIBIOTIC-RESISTANT BRADYRHIZOBIUM STRAIN BY USING GENETIC ENGINEERING METHOD

用三亲本杂交的方法将外源抗药性质粒导入到高效固氮的根瘤菌 Tal377中,外源质粒在 Tal377中能正常表达,但不影响其原有的固氮结瘤能力。利用此抗药性根瘤菌所携带的抗药性,在接种此根瘤菌的同时结合施加一定浓度的抗菌素,抗药性根瘤菌与出发菌株相比表现出一定程度地提高其结瘤固氮能力和占瘤率。

Plasmid P^(G×1252::Tn(?))was transferred from E.coli donor to Bradyrhizo- biurn japonicum strain Tal377 by triparental mating,P^(G×1252::Tn(?))expressed its kanamycia and tetracycline resistibilities in Tal377.The ability of nodulation and nitrogen fixation of MTal377 remained the same as those of Tal377.The nitrogenase activity,plant N content and nodule occupancy were increased when using antibiotic-resistant Bradyrhizobiurn japonicum strain in the presence of antibiotics.