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在ｐＲＫ２０７３的辅助作用下，通过三亲本接合转移，将Ｔｎ５（ｓａｃＢ－ｌｕｘＡＢ）插入华癸根瘤菌７６５３Ｒ菌株基因组中。将３２００个Ｔｎ５标记菌株影印到含有８％蔗糖的ＹＭＡ平板，检测这些菌株的发光酶活性和新霉素抗性。共获得８个菌株，其选择标记消失。质粒检测发现其共生质粒有不同程度的缺失甚至消除。结瘤实验证明，所有共生质粒部分缺失（有的缺失达１／３）的菌株依然结瘤。经用ｌｕｘＡＢ探针的分子杂交证实，８个菌株中有３个对应的标记菌株其Ｔｎ５插在共生质粒上。
Tn5 (sacB-luxAB) was inserted into the genome of R. solani 7653R strain with the aid of pRK2073 by triple-junctional transfer. 3200 Tn5 marker strains were photocopied onto YMA plates containing 8% sucrose and the luminescent and neomycin resistances of these strains were tested. A total of eight strains were obtained, the selection marker disappeared. Plasmid detection found symbiotic plasmids have different degrees of deletion or even eliminate. Nodulation experiments show that all the symbiotic plasmids partially deleted (and some lack of 1/3) strains still nodulation. It was confirmed by molecular hybridization with luxAB probe that three of the eight strains had their Tn5 inserted on the symbiotic plasmid.