Studies on the Development of Acid Tolerant and Superior Nitrogen Fixation Symbionts for Pasture on Hilly Land -I. The Degrees of Acid Tolerance of Rhizobia from the Pastures in Yeongnam Area

야산(野山) 목초지용(牧草地用) 내산성(耐酸性) 우수(優秀) 질소고정균주(窒素固定菌株) 개발(開發) -I. 영남지방(嶺南地方) 목야지(牧野地) 근류균(根瘤菌)의 내산성정도(耐酸性程度)

  • Published : 1987.12.30


This study was conducted to evaluate the degree of acid tolerance of indigenous Rhizobium in natural soils, and to select the superior Rhizobia for legume forage on hilly land. 153 Rhizobial strains isolated from two host genera, Medicago and Trifolium in the pastures of Yeongnam area were screened on acidic agar plates. The results obtained are summarized as follows: 1. The degrees of acid tolerance of R. meliloti and R. trifolii were ranged from 4.3 to pH 5.5 and from 4.0 to pH 5.5 respectively. 2. Among acid tolerant Rhizobia isolates, two strains of R. meliloti at pH 4.3 and three strains of R. trifolii at pH 4.0 were shown to have the activities of nodulation and nitrogenase. 3. R. trifolii strains were shown to survive about 80 to 99% at the pH range 4.8 to 5.0, while R. meliloti were about 35 to 47% at that pH range. Therefore, more acid tolerant R. meliloti should be developed for legume forage in Korean hilly land.