Kurchak O N, Provorov N A, Simarov B V
All-Russia Research Institute of Agricultural Microbiology, St. Petersburg, Pushkin, 196608 Russia.
Genetika. 2001 Sep;37(9):1225-32.
The symbiotic plasmid (pSym1-32) of the highly effective Rhizobium leguminosarum bv. viceae 1-32 strain was identified after the conjugal transfer of replicons carrying Tn5-mob into the plasmidless Agrobacterium tumefaciens Gm1-9023 strain. Plasmid pSym1-32 was transferred into R. leguminosarum bv. viceae strains Y14 (showing low effectiveness of symbiosis with Vicia villosa) and Y57 (unable to fix nitrogen). Transconjugants formed Fix+ nodules on roots of V. villosa and had a highly enhanced nitrogen fixing ability, increased plant weight, and increased nitrogen accumulation compared to the recipient strains. Variation of transconjugants in symbiotic properties (accompanied by alterations in plasmid composition in some of the conjugants) was detected. Moreover, the donor strain R. leguminosarum bv. viceae 1-32 was shown to be more efficient in the competitiveness and acid tolerance than the recipient Y14 strain. Both these properties were transmitted upon transfer of pSym1-32 into the recipient. Thus, plasmid pSym1-32 was shown to carry genes involved in the control of the nitrogen fixing ability, symbiotic effectiveness, competitiveness, and acid tolerance in R. leguminosarum bv. viceae.
在携带Tn5-mob的复制子接合转移至无质粒的根癌农杆菌Gm1-9023菌株后，鉴定出高效豌豆根瘤菌蚕豆生物型1-32菌株的共生质粒（pSym1-32）。将质粒pSym1-32转移至豌豆根瘤菌蚕豆生物型菌株Y14（与绒毛野豌豆共生有效性低）和Y57（不能固氮）。与受体菌株相比，接合子在绒毛野豌豆根上形成固氮阳性根瘤，固氮能力显著增强，植株重量增加，氮积累量增加。检测到接合子共生特性的变异（一些接合子中质粒组成发生改变）。此外，供体菌株豌豆根瘤菌蚕豆生物型1-32在竞争力和耐酸性方面比受体Y14菌株更高效。将pSym1-32转移至受体后，这两种特性均被传递。因此，质粒pSym1-32被证明携带参与控制豌豆根瘤菌蚕豆生物型固氮能力、共生有效性、竞争力和耐酸性的基因。
