• 作者： 楊秋忠
• 作者服務機構： 國立中興大學土壤研究所
• 中文摘要： 本研究是探討鈉鹽對自臺灣大豆分離出的根瘤菌生長、存活及共生特性之影響，比較8個分離菌株在液體培養的差異。結果發現所有菌株在大於5％鈉鹽時，以pH 7之培養液的生長比pH 5之下好，與0.02％鈉鹽之下的結果不同，部分大豆根瘤菌菌株能耐到5％的鈉鹽濃度。結果顯示大豆植株的根瘤菌著生及固氮作用的能力主要受共生根瘤菌之影響。所有之根瘤菌處理在1％鈉鹽下皆無法著生根瘤，分離株SB 142之處理能使大豆在0.5％鈉鹽下著生根瘤。大豆每克根瘤的固氮酵素活性在0.5％及0.02％鈉鹽間並無明顯差異，此結果指出鈉鹽對共生根瘤菌－大豆系統中的影響的現象是著生根瘤減少，而不是影響每克根瘤的固氮酵素活性。鈉鹽影響根瘤著生可能包括直接及間接之作用，有待深入研究。
• 英文摘要： The effect of sodium salt on the growth, survival and symbiotic characteristics of Rhizobium japoni-cum isolated from Taiwan soils were studied. Eight isolates in culture media at pH 5 and pH 7 were com-pared. All isolates in the medium with higher concentration of salt (>5% NaCl) at pH 7 grew better thanin the medium at pH 5, but results were different in low concentration of 0.02% NaCl. Some isolates ofR. japonicum survived in the liquid culture at as high salt concentration as 5%. The nodulation and nitro-genase activity of soybean plants were affected by rhizobial symbiont. No nodulation of soybean plants inany isolates treatments were observed at 1% NaCl. The appreciable nodulation of soybean plants took placeat 0.5% NaCl for the inoculation with a isolate-SB 142. No difference in specific activity of nitrogenase inthe nodules of soybean was found between salt stress at 0.5% NaCl and 0.02% NaCl. The results showedthat a phenomenon of salt stress on the symbiotic Rhizobium-soybean system caused the decrease in no-dulation, but not in the specific activity of nitrogenase.
• 中文關鍵字： Glycine max; mitrogen fixation; Rhizobium japonicum; salinity
• 英文關鍵字： --