CO_2浓度倍增和干旱胁迫对黄瓜幼苗叶片转化酶活性及糖代谢的影响

Effects of doubled CO_2 concentration and water stresses on invertase activities and carbohydrate metabolism in leaves of cucumber seedlings

【目的】揭示干旱条件下黄瓜幼苗对CO2浓度升高的生理响应及调节机制,为设施CO2施肥或未来大气CO2浓度升高及水分亏缺等逆境胁迫下,黄瓜的优质高效栽培提供理论依据和技术参数。【方法】以黄瓜(Cuc-umis sativusL.)品种津优1号三叶期幼苗为试材,在水培条件下研究CO2浓度倍增与聚乙二醇(PEG 6000)模拟干旱胁迫对黄瓜幼苗叶片转化酶活性表达及葡萄糖、果糖和蔗糖代谢的影响。【结果】CO2浓度倍增显著提高了75 g/kg和100 g/kg PEG 6000胁迫条件下黄瓜幼苗叶片的可溶性酸性转化酶和碱性转化酶活性及葡萄糖、果糖和蔗糖含量,而且CO2浓度倍增对50 g/kg PEG 6000胁迫也具有一定的缓解作用。【结论】CO2浓度倍增能显著抵御水分胁迫逆境反应,从而提高黄瓜的抗旱性,且这种效应在中度水分胁迫时表现较为明显。

【Objective】 The study was to reveal effects of doubled CO2 concentration and different level of water stresses on invertase activities and carbohydrate metabolism in leaves of cucumber seedlings,and to provide theoretical bases and technological parameters for cucumber culture under CO2-fertilized greenhouse or changed climatic conditions in the future.【Method】 The effects of CO2 concentrations and drought stresses on invertase expression and carbohydrate metabolism of cucumber（Cucumis sativus L.cv.Jinyou No.1） seedlings were studied under hydroponic culture.【Result】 The results showed that doubled CO2 concentration significantly enhanced both soluble acid and alkaline invertase activity,and increased content of glucose,fructose and sucrose of cucumber leaves under 75 g/kg and 100 g/kg PEG 6000 treatments.In addition,the results indicated that doubled CO2 concentration could alleviate the negative effect of 50 g/kg PEG 6000 treatment.【Conclusion】 Doubled CO2 concentration improved the drought resistance of cucumber seedlings,and the effects were significant under moderate water stress.