大豆基因工程根瘤菌田间结瘤和共生固氮效应

利用三亲本接合转移方法,将快生型大豆根病菌B_(52)的基因文库克隆转移到受体菌慢生型大豆根瘤菌2210中,获得4株大豆基因工程根瘤菌(32.43、B—2—6、B—3—8)。田间接种试验表明:在大豆分枝期(V2),43和32结瘤效分别比不接种对照增加117.9％和100.4％;在初花期(R_1),32和B—2—6结瘤数分别比对照增加122.5％和91.6％,根瘤固氮酶活性增加233.3％和195.6％;在结荚始期(R3),B—2—6和32结瘤数比对照增加78.5％和70.1％,根瘤固氟酶活性43和B—2—6分别比对照增加53.4％和49.3％。产量统计表明:32、B—2—6和43比对照分别增产16.8％、14.3％和12.2％,亩增收大豆分别为28.2、24.1和20.6公斤。以上三个菌株均比受体菌株2210增产率高。

The Effect of Symbiotic Nitrogen Fixation of Gene Engineering Rhizobium Strains in Soybean in the Field

Triparent mating was made between BU gene library and 2210(slow-growing) .With the help of pRK 2013. The cojugates were obtained on the SM(E. coli could not grow)-(-Tc(2210could not grow)plats. They were inoculated into soybean grown in fluid culture bottles, some related paraments were examined, four gene engineering strains (32,43.8-2 - 6 and B-3 -8)were obtained, pbt experiment was carried, out by using these strains inoculated into soybean plants. The result indicated the strains of 43 and 32 increased nodule numbers by 117. 9% and 100.4% at V2 development stoge respectively,compared to noinoculation. At R2 stage 32 and B-2-6 increased nodle numbers and nitrogenase activity by 12. 2% 91. 6%and 233. 3% 195. 6%, respectively compared to noinoculation. At R3 stage.the strains of B-2-6 and 32 increased nodule numbers by 78. 5% and 70. 1% ,43 anb B-2 -6 increased nitrogenase activity by 53. 4% and 49. 3% .respectively, compared to nonoculation. The result also increase yield by 16. 6% ,14. 3% and 12. 2%,respectively, com pared to CK. This three strains were higher nodulabon and nitrogen fixation abilities than original strain 2210.