植物工厂不同LED光照模式对生菜幼苗生长及光合特性的影响

Effects of different LED lighting regimes on the growth and photosynthetic characteristics of lettuce seedlings in plant factory

通过研究不同LED光照模式对植物工厂中生菜(Lactuca sativa L.)幼苗生长及光合特性的影响,筛选适于植物工厂内生菜育苗的LED光照模式。本试验使用白色LED(W)、红色LED(R)和蓝色LED(B)为光源,光源与光照天数相结合组成9种处理,分别为:W19、R19、B19、W12B7、W12R7、B12W7、B12R7、R12B7、R12W7,以W19为对照。研究结果表明:W19、B19、W12B7、W12R7、B12W7、B12R7处理下生菜幼苗的茎长显著短于其它处理。R19、W12R7和B12R7处理下生菜幼苗的地上部干鲜重、叶面积以及整株光合速率均显著高于对照;硝酸盐含量显著低于对照。W19、R12W7和B12W7;B19、W12B7和R12B7处理下生菜幼苗的叶绿素、花青素含量均高于R19、W12R7和B12R7。B19、W12B7和R12B7处理下生菜幼苗的单叶光合速率和气孔导度均显著高于其他处理。在供试的处理中,W12R7和B12R7处理下生菜幼苗的地上部干鲜重和叶面积较高、茎长短、硝酸盐含量低、整株光合速率高,表现出明显的生长优势,较其它处理更适用于植物工厂生菜育苗。

In order to select the optimum LED lighting regimes for the production of lettuce（Lactuca sativa L.）seedlings in plant factories,comparative experiments were conducted for the effects of different LED lighting regimes on the growth and photosynthesis of lettuce.In this research,white LED（W）,red LED（R）and blue LED（B）were used as light sources.Nine treatments were denoted by light sources and irradiating days： W19,R19,B19,W12B7,W12R7,B12W7,B12R7,R12B7 and R12W7.The results showed that the values of stem length of lettuce seedlings grown under W19,B19,W12B7,W12R7,B12W7,and B12R7 were significantly lower than those under other regimes.Shoot fresh weight,shoot dry weight,leaf area and whole-plant photosynthetic rate of seedlings grown under R19,W12R7,and B12R7 were significantly higher than those of other treatments.Nitrate contents of seedlings grown underR19,W12R7,and B12R7 were significantly lower than those of other treatments.Seedlings treated with W19,R12W7,B12W7,B19,W12B7 and R12B7had higher anthocyanin and chlorophyll contents than those treated with R19,W12R7,and B12R7.Photosynthetic rate and stomatal conductance of single leaf in seedlings grown under B19,W12B7 and R12B7were significantly higher than those of other treatments.Among all treatments,W12R7 and B12R7were the two optimized irradiation combinations for the raising of lettuce seedlings.Under these two regimes lettuce seedlings showed higher values of aboveground biomass and leaf area,shorter stem length,lower values of nitrate content and higher whole-plant photosynthetic rate,which demonstrated growth advantage obviously.