CO_2浓度对黄瓜叶片光合速率、RubisCO活性及呼吸速率的影响  

Effect of CO_2 Concentrations on Photosynthetic Rate,RubisCO Activity and Respiratory Rate of the Cucumber Leaves

作　　者：于国华[1] 张国树 战淑敏 罗文熹 

机构地区：[1]莱阳农学院

出　　处：《华北农学报》1997年第4期101-106,共6页Acta Agriculturae Boreali-Sinica

摘　　要：研究了在２００、３５０、５００、７００、１０００ｍｇ／ｋｇＣＯ２浓度处理下的黄瓜叶片的光合速率、呼吸速率及双磷酸核酮糖羧化加氧酶（ＲｕｂｉｓＣＯ）活性。结果表明，增加ＣＯ２浓度，可显著提高黄瓜叶片的光合速率，在强光下，效果尤其明显。黄瓜叶片光合速率对不同ＣＯ２浓度的响应都有一个由低到高再低的趋势。黄瓜叶片暗呼吸在短时间内，随ＣＯ２浓度的增加而提高，随着时间的延长（６ｍｉｎ后），各种ＣＯ２浓度下的呼吸速率都降至相似的低水平。此时，ＣＯ２浓度不影响暗呼吸速率。空气ＣＯ２浓度，细胞间隙ＣＯ２浓度与光合速率是一致的，在高ＣＯ２浓度下，气孔导度一般不是光合速率的限制因子。黄瓜叶片双磷酸核酮糖羧化酶活性，随ＣＯ２浓度的增加而提高，ＲｕＢＰ加氧酶活性降低，ＲｕＢＰ加氧酶与羧化酶之比亦下降。但在ＣＯ２浓度超过５００ｍｇ／ｋｇ后。This experiment dealt with the influence of CO_2 at the concentrations of 200,350,500,700 and 1000 mg/kg on photosynthetic and respiratory rates and RubisCO activity. The results showed that the CO_2 enrichment did increase the photosynthetic rate of upper leaves of cucumber, especially under intensive light conditions. The response of photosynthetic rate to the different CO_2 concentrations appeared low at the beginning, then higher and finally lower. The respiratory rates of these leaves increased rapidly with the enrichment of CO_2, until 6 min. Later all dropped to their lowest levels despite the CO_2 concentrations, from when there was no notable effect of CO_2 concentrations on the respiratory rates. The photosynthesis rate was positively correlated with the atmospheric and intercellular CO_2 concentrations. Generally the stomatal conductance was not a factor to inhibit photosynthetic at high CO_2 concentrations. The RuBP carboxylase activity was enhanced while RuBP oxygenase activity and also the ratio of the former to the latter decreased. Nevertheless,when the CO_2 concentrations were over 500mg/kg,the activity of RuBP carboxylase increased slightly.

关 键 词：黄瓜 二氧化碳浓度 光合速率 呼吸速率 

分 类 号：S642.201[农业科学—蔬菜学]