不同光照时间红蓝LED光对生菜生长和品质的影响

生菜(Lactuca sativa var. ramosa Hort.)富含维生素、花青素和胡萝卜素等营养成分,且具有抗衰老和抗癌功能1] ,是可控环境下主栽蔬菜种类之一. 光照时间能调控植物开花、花性分化、发育进程及光合生长2-3]. 夜间补光和低光量子通量密度条件下延长光照时间可以提高生菜的生物量和品质4-5]. 全人工光照条件下,红蓝光是培育植物的适宜光谱6-7].

Effects of different illumination times of red and blue LED lights on growth and quality of Lactuca sativa var.ramosa

Effects of different illumination times ( 8, 12 and 16 h·d-1 ) of 200μmol·m-2 ·s-1 red and blue LED lights with photon flux density ratio of 3:1 on growth and quality of Lactuca sativa var. ramosa Hort. were investigated. The results show that different illumination times of red and blue LED lights have no significant influence on leaf number per plant, plant height, root length per plant and root activity of L. sativa var. ramosa. Leaf area per plant, and fresh and dry weights of above-ground part per plant and whole plant in illumination time of 12 h·d-1( T2 group) are significantly higher than those in illumination time of 8 h · d-1 ( T1 group ) , but have no significant difference with those in illumination time of 16 h·d-1 ( T3 group) . In general, contents of chlorophyll a, chlorophyll b, and total chlorophyll in leaf in T2 and T3 groups are significantly higher than those in T1 group, while illumination time has no significant influence on carotenoid content in leaf and quality of L. sativa var. ramosa. Contents of soluble sugar and sucrose in leaf in T2 group are relatively high, while contents of soluble protein and vitamin C in leaf in T3 group are relatively high. Illumination time of 12 h·d-1 of 200μmol·m-2 ·s-1 red and blue LED lights with photon flux density ratio of 3:1 is recommended for promoting growth of L. sativa var. ramosa in plant factory.