快生型大豆根瘤菌G113的几个共生特性

快生型大豆根瘤菌G113是从吉林省、公主岭黑土上生长的野生大豆G3的根瘤中分离获得。野生大豆G3在有快慢生型大豆根瘤菌同时存在时,选择G113和其共生。G113菌株和吉林20大豆共生优于轻碱土中的土著大豆根瘤菌。因此在轻碱土上、吉林20大豆接种G113菌株有增产趋势。

SOME SYMBIOTIC CHARACTERISTICS OF RHIZOBIUM FREDII G113

Bhizobium fredii or Sinorhizobium fredii G113 was isolated from a nodule of Glycme soja 3 in black earth of Gongzhuling, Jilin Province. It was identified to be Rhizobium fredii or Sinorhizobiium fredii by the method recommended by the both "The general method for identification of bacteria".This study indicated that strain G113 was more competitive on nodulation than Bradyrhizobi-um japonicum B15 and 110 on Glycine soja 3. When strain G113 absent, Glycine soja 3 can be nodulated by strains B15 and 110, But when mixed the three strains B15, 110 and 110, Glycme soja 3 was 100% nodulated by G113.163 indigenous isolates from 163 nodules of soybean cultivars in light saline-alkali soil in 1984 , 1987 and 1989 were identified to be R. fredii by generation time, nodulation and nitrogen fixation activity. Among which strain 515 was the most active on nitrogen fixation, and this result also showed that the fast growing R. japonicum is the main type in the light-saline alkali soil.An experiment of strain G113 and strain 515 under aseptic condition was carried out. The result showed that the plant dry weight of the soybean CV. Jilin 20 was increased by inoculating both G113 and 515 and ranged from 23-63%. The dry weight of the soybean plant inoculated with G113 was 32% larger than that inoculated with strain 515. At means that strain G113 was more effective or appropriate than indigenous strian 515 on soybean cv. Jilin 20. Field inoculation of strain G113 on light saline-alkali soil showed that seed yield of soybean cv. Jilin 20 was increased by 21.5% in Nongan county in 1988, and by 13. 3% in Shuangliao county in 1989. 100 seeds weight tended to increase in both place.These results also showed that the increase of yield in light saline - alkali soil will be achieved by inoculating a strain of R. fredii. which is more effective than the indigenous one.