受控环境中二氧化碳浓度对生菜生长发育的影响

Effects of CO_2 Concentration on Growth and Development of Lettuce in Controlled Environment.

目的研究受控生态生保系统中获得高产优质美湖包心生菜的二氧化碳高浓度极限值。方法在新近建成的空间高等植物栽培地面实验装置中 ,进行了 5批次不同二氧化碳浓度实验 ( 2 0 0 0～ 1 0 0 0 0μmol·mol- 1 ) ,其它诸多参数保持恒定。栽培期间进行了植株形态学观察 ,记录了每日二氧化碳添加量、营养液补充水添加量和冷凝水收集量等 ,收获后进行了产量和光合效率计算及植物多种组分的分析等。结果生菜在二氧化碳浓度为 60 0 0 μmol·mol- 1 时栽培效果比较理想 ,80 0 0 μmol·mol- 1 时产量有所提高但品质略有下降 ,而当达到 1 0 0 0 0 μmol·mol- 1 时则出现明显的中毒凋亡现象 ,此时产量和品质均极差。结论在上述情况下 ,美湖包心生菜栽培舱内二氧化碳浓度最好控制在 60 0 0 μmol·mol- 1 以内。

Objective To study the tolerance of lettuce to elevated CO 2 concentration in Controlled Ecological Life Support System(CELSS). Method Lettuce was cultivated in the Ground based Experimental Facility for Higher Plant Cultivation in Space (GEFHPCS), in which many parameters were kept unchanged, while concentration of CO 2 was controlled at 5 different levels(2000～10000 μmol·mol -1 ). During the growing periods, the morphologies of lettuce were observed every day, the replenished amounts of CO 2 to GEFHPCS and water to the nutrient fluid box as well as the amounts of condensed water collected from GEFHPCS were all recorded every day. After harvest, the output and photosynthetic rate were calculated and lots of constituents of lettuce were analyzed. Result The growth of lettuce were relatively ideal when CO 2 concentration was at 6000 μmol·mol -1 , but an obviously withering appearance was found when CO 2 concentration increased 10000 μmol·mol -1 , this time the output and quality of lettuce were unsatisfactory. Conclusion It would be optimal when CO 2 concentration is controlled at about 6000 μmol·mol -1 in a lettuce cultivating chamber.