【摘要】 用液相氧电极测定离体悬浮生长发菜细胞的光合速率和呼吸速率的结果表明,发菜细胞的光补偿点为15￣16μmol·m-2·s-1,光饱和点为90μmol·m-2·s-1,光抑制点为190μmol·m-2·s-1。25℃下发菜细胞光合速率最高,呼吸速率则在10￣50℃范围内随温度升高而增强。发菜细胞光合作用的最适pH值为7.0￣7.5,呼吸作用最适pH值为9.0。BG110无氮培养基中添加30mmol·L-1NaNO3,发菜细胞的光合速率增加约20%。培养基中Na2HPO4浓度为1.75mmol·L-1时,细胞光合速率和呼吸速率最大,随后保持稳定。钾盐浓度变化对发菜细胞光合速率和呼吸速率的影响不显著。更多还原

【Abstract】 Photosynthetic and respiratory rates of cells from Nostoc flagelliforme Born. et Flah. were deter-mined by using an oxygen electrode. The results showed that photosynthetic light compensation point of cells was 15–16 μmol·m-2·s-1,light saturation point was 90 μmol·m-2·s-1 and light inhibition point was 190 μmol·m-2·s-1. The optimum temperature for photosynthesis was 25℃. Respiratory rate was increased with the increase of temperature at range from 10℃ to 50℃. The optimum pH for photosynthesis was 7.0–7.5 and that for respira-tion was 9.0. Photosynthetic rate of cells was increased about 20% when 30 mmol·L-1 NaNO3 was added into medium. Cells exhibited maximum photosynthetic and respiratory rates when 1.75 mmol·L-1 Na2HPO4 was in medium. The effect of change in potassium concentration on photosynthetic and respiratory rates of cells was inapparent.更多还原