不同光质配比对紫叶生菜光合特性和品质的影响

Effects of light quality ratio on photosynthetic characteristics and quality of purple lettuce

为了探索不同光质配比对紫叶生菜生长发育的影响,本试验以‘中蔬紫生菜'紫叶生菜为研究对象,以LED智能调光台为人工光源,通过在白光的基础上添加不同比例的红蓝光(1∶1、2∶1、4∶1和1∶2),研究不同光质配比对紫叶生菜光合特性和品质的影响.结果表明:红蓝光比例为4∶1时,紫叶生菜叶片叶绿素含量、RuBP羧化酶活性最大,电子传递效率最高,净光合速率和生长量也显著高于对照和其他处理,且硝酸盐含量最低.而添加1∶2的红蓝光时,叶片可溶性蛋白和维生素C含量最高,花青素、类黄酮、总酚等次生代谢物含量以及总抗氧化能力显著高于对照和其他处理.因此,在白光基础上增加适当比例的红蓝光可提高紫叶生菜的光合特性或改善产品品质.

To explore the effects of different light quality ratios on the growth and development of purple lettuce,we used LED intelligent light control console as light source to study the effects of adding different proportions of red and blue light（1： 1,2： 1,4： 1 and 1： 2） to the white light on photosynthetic characteristics and commercial quality of purple lettuce（Lactuca sativa L. cv‘Zhongshu Purple Lettuce＇）. The results showed that when the ratio of red to blue light was 4： 1,the chlorophyll content,RuBP carboxylase activity,electron transport efficiency of photosynthesis,net photosynthetic rate and growth were all significantly higher than that in control and other treatments,whereas the nitrate content was the lowest. When the ratio of red to blue light was 1： 2,the contents of soluble protein,vitamin C,secondary metabolites such as anthocyanins,flavonoids,total phenolic compounds,and the contents of antioxidant capacity were significantly higher than those in the control and other treatments. We concluded that adding appropriate ratios of red to blue light to the white light could increase photosynthesis and improve commercial quality of purple lettuce.