우리나라 토착대두근류균(土着大豆根瘤菌)의 분포상태(分布狀態)와 생리(生理) 및 생태학적(生態學的) 특성(特性) -제(第)III보(報) 토착대두근류균(土着大豆根瘤菌)의 질소고정효율 및 Nitrate reductase 특성(特性)

Physiological and Ecological Characteristics of Indigenous Soybean Rhizobia Distributed in Korea -III. Symbiotic Effectiveness and Nitrate Reductase Characteristics of Indigenous Soybean Rhizobia

전보(前報)에 이어 토양별(土壤別) 토착대두근류균(土着大豆根瘤菌)의 분포(分布), 질소고정효율(窒素固定效率) 및 Nitrate reductase 특성(特性)을 비롯하여 동일(同一)한 토양조건(土壤條件)에서 토착대두근류균(土着大豆根瘤菌)과 대두품종별(大豆品種別) 친화성(親和性)을 조사(調査)한 결과(結果)는 다음과 같다. 1. 토착근류균(土着根瘤菌) 중 대두근류(大豆根瘤)를 형성(形成)할 수 있는 토착대두근류균(土着大豆根瘤菌)은 $0.9{\sim}42.4{\times}10^3\;cells/g$ soil 범위(範圍)로서 토양간(土壤間)에 상이(相異)하였고 특(特)히 석회암토양(石灰岩土壤)에서 균밀도(菌密度)가 높았다. 2. 토양별(土壤別) 질소고정효율(窒素固定效率)은 대두연속재배지(大豆連續栽培地) 및 석회암토양(石灰岩土壤)에서 높았으며, 토착근류균수(土着根瘤菌數)가 많았던 토양(土壤)에서 질소고정효율(窒素固定效率)도 많은 경향(傾向)이있다. 3. 대두근류(大豆根瘤)의 bacteroid에서 질소고정효소(窒素固定酵素)와 질산환원효소(窒酸還元酵素)와의 상호관계(相互關係)에서 TNA와 NRA간(間)에는 유의(有意)한 부(負)의 상관관계(相關關係)($r=-0.52^*$)를 보였으나 SNA와 NRA과는 대두근류(大豆根瘤)의 분리원간(分離源間)에 2개군(個群)으로 구분(區分)되었다. 4. 동일(同一)한 토양조건(土壤條件)에서 토착대두근류균(土着大豆根瘤菌)과 대두품종간(大豆品種間) 친화성(親和性)은 품종간(品種間)에 상이(相異)하였으며 질소고정효율(窒素固定效率)이 높았던 품종(品種)은 장엽(長葉) 및 광교(光敎)로 나타났다.

In order to improve effectiveness of rhizobia- legume symbiotic nitrogen fixation, ecological and physiological characteristics of indigenous rhizobia distributed in Korea, that is, symbiotic effectiveness of indigenous soybean rhizobia, nitrate reductase activities of the soybean bacteroid from five different soils, and differences of host-infection abilities among the soybean cultivars under population densities of the same indigenous soybean rhizobia, were investigated. The results were summarized as follows: 1. The number of indigenous soybean rhizobia was ranged from $9.2{\times}10^2$ cells per gram of soil in calcareous soil II to $42.4{\times}10^3$ cells per gram of soil in calcareous soil I in Danyang. 2. The symbiotic effectiveness of indigenous soybean rhizobia from five different soils was high in the case of soybean continuously cultivated, and calcareous soil I that population densities of indigenous soybean rhizobia were observed highly. 3. Inverse relationship was observed between total nitrogenase activity (TNA) and nitrate reductase activity (NRA) from the soybean bacteroids ($r=-0.502^*$), but the correlation between nitrate reductase and specific nitrogenase activities (SNA) could be devided into two groups. It was classified into group I which is high in SNA and low in NRA, and group II which is low in SNA and high in NRA. 4. The infection ability of the indigenous soybean rhizobia in the same soil conditions showed the reciprocal difference among each soybean cultivars. In Kwangkyo and Jangyeup, the symbiotic effectiveness appeared by infection of indigenous soybean rhizobia was higher than it of the other soybean cultivars.