高温、高湿及CO_2施肥条件下黄瓜光合性能的变化

Change of Photosynthetic Performance of Cucumber under the Condition of CO2 Fertilization and High Temperature and High Humidity

[目的]探讨温度、湿度及CO2施肥条件的变化对黄瓜光合性能的影响。[方法]以津春5号黄瓜为材料,设高温、高湿和高温、常规湿度2个处理,以常规黄瓜生产管理为对照,在CO2施肥条件下,研究黄瓜光合性能的变化。[结果]每天中午平均35-45℃的高温下处理黄瓜4 h以上,其叶片的净光合速率明显高于对照。在高温、高CO2浓度、高湿和强光综合作用下,黄瓜的“午休”现象有减缓趋势。高温处理开始会使黄瓜叶片中叶绿素含量下降,但经过7 d左右就能恢复,而高温、常规湿度区恢复幅度较小。高温处理使黄瓜叶片中积累的淀粉通过呼吸作用分解运出,避免叶绿体遭受淀粉积累的毒害。[结论]该研究为高温季节和CO2施肥条件下温室黄瓜的生产管理提供了参考依据。

[ Objective ] The aim was to discuss the effects of the changes of temperature, humidity and CO2 fertilization on the photosynthetic performance of cucumber. [ Method] With the cucumber Jinchun 5 as material, 2 treatments with high temperature combined with high humidity and high temperature combined with routine humidity were set up and with the routine production management of cucumber as CK, the change of photosynthetic performance of cucumber was studied under the condition of CO2 fertilization. [ Result] The net photosynthetic rate of cucumber leaf was significantly higher than that of CK when the cucumber was treated with high temperature of average 35 - 45℃ for more than 4 h at noon daily. Under the comprehensive action of high temperature, high CO2 concn. , high humidity and high light, the midday depression phenomenon of cucumber showed delaying trend. The treatment with high temperature would decrease the chlorophyll content of cucumber leaf at the beginning and its chlorophyll content could renew in about 1 week but the renewing extent of the treatment with high temperature combined with routine humidity was less. The treatment with high temperature could make the amylum accumulated in cucumber leaf decomposed and exported through respiration, which could protect chloroplast from the poisoning of amylum accumulation. [ Conclusion ] The study provided reference for the production and management of greenhouse cucumber under the condition of CO2 fertilization in high temperature season.