玉米联合固氮工程菌的研究  

Research on Associating Nitrogen Fixing Engineered Bacteria of Maize

作　　者：李久蒂[1] 李永兴[1] 董越梅[1] 安千里[1] 王继文[1] 张燕[1] 匡柏健[1] 隋文志[2] 卢林纲[2] 钟鄂荣[2] 唐颖[2] 卢明峰[2] 王焱[2] 林琳[2] 

机构地区：[1]中国科学院植物研究所,北京100093 [2]黑龙江省农垦科学院作物所,佳林斯154007

出　　处：《高技术通讯》1999年第12期47-50,共4页Chinese High Technology Letters

基　　金：863 计划资助项目!(863101030402)

摘　　要：用分子生物学手段改造玉米联合固氮菌, 解除铵对固氮酶合成的阻遏作用, 以期增加对宿主的氮素供应, 改善与宿主根系的相互关系。经接合转移法把载有组成型表达nifA 基因的pCK3 质粒导入从玉米根分离到的根际联合固氮菌Enterobactergergoviae577,得到耐铵工程菌E7 。E7 在50m mol/LNH+4 下恢复76% 固氮酶活性,接种E7 使玉米固氮率增加14% ,并促进玉米次生根分化及根系生长。E7 的接种效应与玉米品种有关。连续三年在白浆土、砂壤土低产田田间小区接种实验表明,在相同施肥水平条件下接种工程菌E7 比接种野生型菌平均增产8-8 % ,比不接菌对照平均增产12-3% ,生物统计差异显著(P= 0-05) 。在相同产量条件下,接种工程菌E7 比无菌对照节省15% ～20% 氮肥,比接种野生型菌节省15%The associating nitrogen fixing bacteria in maize were reformed by the molecular biological techniques for removing the NH + 4 repress of a nitrogenase synthesis, enhancing the supply of a host plant and improving the relation with host roots. The plasmid pCK3 which carried a Klebsiella pneumoniae nifA gene expressed constitutively was introduced into the associating nitrogen fixing bacteria Enterobacter gergoviae57 7. A NH + 4 tolerant engineered bacteria E.gergoviae E7 was obtained. E7 recovered the 76% nitrogenase activities in 50mmol/L NH + 4. E7 was responsible for 14% increase in the nitrogen fixing ratio in a maize host. E7 inocula promoted the differentiation of secondary roots and the growth of roots of maize. The inoculating efficiency of E7 was related with the species of maize. The field plat inoculating experiments were carried out over three years in an albic bleached soil and a sabulous soil. The results showed that at the same levels of fertilizer, the E7 inocula resulted in increased maize yields(an average 8.8%) from wild type strain inocula and increased maize yields (an average 12.3%) from a no bacteria control. The differences were statistically significant (P=0.05). At the same level of yield, E7 inocula resulted in saving of 15%～20% nitrogen fertilizer from no bacteria control and saving 15% nitrogen fertilizer from wild type strain inocula.

关 键 词：耐铵工程菌 玉米 联合固氮菌 施肥 细菌肥料 

分 类 号：TQ446.1[化学工程—化学肥料工业] S513.062[农业科学—作物学]