关键词: 羊奶果, 固氮活性, 氢酶活性, 硝酸还原酶活力

Abstract: Elaeagnus conferfa is a tropical fruit tree, which is one of Actinorhizal plants, bearing perennial, multiple branching, coralloid no-dule clusters. The nitrogenase activity of nodule clusters of the plant was higher than that of the eight species of non-leguminous nodulated plants determined in Xiamen. The seasonal variation of nodules nitrogenase activity was found higher in autumn and summer than in spring find winter. The optimum temperature for nitrogen fixation of nodules ranged 25-30℃. The nitrogenase activity reduced below 25℃ or Over 30℃. The uptake hydrogenase activity of nodules was 9.52 μmol H₂/g·FW/h, When adding 5% H₂ to reaction system, nitrogenase activity in nodules increased markedly. The in vivo nitrate reductase (NR) activity in E. conferta young trees was determined. The NR activity in different organs was in the order roots > nodules > leaves > shoots.NR activity in leaves was higher in autumn and summer than in spring and winter.

Key words: Elaeagnus conferta, Nitrogenase activity, Hydrogenase activity, NR activity