中文摘要：

以镝灯为对照，探讨了不同配比的红（R）蓝（B）LED光对叶用莴苣生长、营养品质和硝态氮含量的影响。结果显示：R处理的叶面积显著大于其他处理；与对照相比，R：B=1：1和R处理的鲜质量无显著变化；LED光处理的能效显著提高，其中R：B=1：1处理的能效最高，R处理次之。光质显著影响叶用莴苣的品质，R处理地上部的可溶性糖、淀粉、蔗糖及粗纤维含量均显著高于其他处理；但R处理的蛋白质、维生素C及花青素含量显著低于有蓝光的LED处理，且硝态氮含量也显著大于蓝光比例较小的R：B=1：1处理。从生长、品质及能效综合考虑，红光对叶用莴苣的生长有促进作用，且对叶用莴苣中可溶性碳水化合物和含水量等营养品质有显著的提高作用，适当补充比例较小的蓝光使叶片肥厚并提高叶用莴苣中维生素C、花青素和蛋白质含量，同时可降低硝态氮含量。

英文摘要：

With dysprosium lamp as the control, the effects of different ratio red（R） and blue（ B ）LED on the growth, nutritional quality and nitrate nitrogen content of lettuce were investigated. The results showed that the leaves area of the R treatment was significantly greater than that of other treatments. Compared with the control, the fresh biomass of R ： B = 1 ： 1 and R treatments had no significant changes;the energy, efficiency of each LED treatment all increased, and the energy efficiency of the R：B = 1：1 treatment was the greatest, followed by R treatment. Different light quality also significantly affected the quality of the lettuce. The soluble sugar, starch, sucrose and crude fiber contents of the shoot of R treatment were significantly greater than those of other treatments. However, the protein, anthocyanin and vitamin C contents of R treatment were significantly lower than those of other LED treatments containing blue LED. Furthermore, the nitrate nitrogen content of R treatment was also significantly lower than that of the R ： B = 1 ： 1 treatments. In view of the growth and quality of lettuce and energy consumption, monochromatic red light was beneficial for the growth of lettuce, and could significantly improve contents of soluble carbohydrate and water in plant,and to supply lower dose blue light can make leaves thicker, and significantly improve the contents of vitamin C and protein in plant,and also could reduce the nitrate nitrogen content of lettuce.