不同光质对黄瓜幼苗抗旱性的影响

Effects of light quality on drought resistance of cucumber seedlings

利用LED光源,研究了白光、蓝光、红光和红蓝(1∶1)组合光对干旱逆境下黄瓜(Cucumis sativus L.)植株净光合速率、蒸腾速率、气孔开度、活性氧累积、抗氧化酶活性等的影响。结果表明,与白光处理相比,红光可以降低植株气孔开度、蒸腾速率和失水率,并能增加抗氧化酶SOD、CAT和G-PDO活性,降低活性氧的累积,但红光不利于正常浇水条件下黄瓜植株的光合作用;蓝光则促进气孔开放和蒸腾速率,不利于植株保水。因此,在设施生产中适当补给红光有利于黄瓜幼苗抗旱性的提高。

To study the effects of light quality on drought resistance of plant,cucumber seedlings were exposed to white light,blue light,red light or red-blue（1∶ 1） light from light-emitting photodiodes（LED） under well watered conditions or drought conditions and the net photosynthetic rate（Pn）,transpiration rate（Tr）,stomatal aperture,reactive oxygen species（ROS） and antioxidant enzyme activity in leaves were investigated. The results showed that plants grown with red light had improved drought tolerance,together with decreased leaf stomatal aperture,transpiration rate,water loss and ROS accumulation,and higher activities of SOD,CAT and G-POD. However,red light decreased Pn in well watered plants. Blue light promoted stomatal aperture and Tr. Our study suggests that exposure to red light appropriately could be a potential approach to improve drought tolerance in cucumber seedlings which is particularly feasible for greenhouse production.