LED光调控对滇重楼皂苷组分含量和同位素分馏的影响机理

Intensity, quality and duration of light play a key role in growth and accumulation of secondary metabolites of medicine herbs, and also have closely relationship with stable isotope fractionation, but of which the researches aren't deep and systematic, the mechanisms are unclear, the results and measurements related to light quality aren't reasonable. Paris polyphylla var.yunnanensis, a special effective Chinese herb, is on the edge of extinction. There are many serious problems still existing in artificial cultivation of Paris polyphylla var.yunnanensis , such as extremely slow growth of rhizome, unstable effective components in rhizome, immature cultivation techniques, etc. Our former research found that the transmittance and sunlight duration had significant influence on growth, saponin accumulation and fractionation of C, O stable isotope in rhizome of Paris polyphylla var.yunnanensis. Adopting modern light regulation technique (LED light source regulate light quality accurately), applying stable isotope ecology, physio-ecology of medicinal plants, plant cell biology , etc. multi-discipline theories and methods, this project aims to explore the effect of intensity, quality and duration of light on growth, components and content of saponins, stable isotope fractionation, to reveal the mechanisms in plant physio-ecology. The results will clarify the effect and mechanism of light on components and content of saponins, stable isotope fractionation, reveal the rule of light on growth, secondary metabolism, and stable isotope ratio, and provide theory evidence for artificial cultivation with high yield and good quality of Paris polyphylla var.yunnanensis, and for origin trace of Chinese herbs under light regulation.

光强、光质和光期对药用植物生长和次生代谢产物累积起关键作用，与稳定同位素分馏密切相关。但此方面的研究不够深入系统、机理不清、有关光质的研究结果和手段不够严谨。滇重楼属濒危中药材，目前人工栽培中存在根茎生长极其缓慢、药效成分不稳、栽培技术不成熟等瓶颈问题。我们前期研究发现，透光率和日照时数对滇重楼根茎生长、皂苷累积和C、O同位素分馏有显著的影响。本项目采用现代光调控技术（LED光源精确调制光质），运用稳定同位素生态学、药用植物生理生态学、细胞生物学等多学科的理论和方法，探索光强、光质和光期对滇重楼生长、皂苷组分和含量、稳定同位素分馏的影响，从生理生态的角度探讨其响应的机理。研究结果对阐明光对滇重楼皂苷组分含量、稳定同位素分馏的影响机理，揭示光对滇重楼生长、次生代谢和稳定同位素比率的影响规律有重要理论意义。为滇重楼高产优质栽培，以及光调控下中药材溯源提供技术支撑。

滇重楼是云南道地中药材，药效独特，药用价值极高。人工栽培中存在药用部位生长极其缓慢、药效成分不稳、栽培技术不成熟等瓶颈问题。与传统光源相比，LED光源具有光质纯、光效高、波长类型丰富、体积小、寿命长、发热低、光质组合易等优点，利用LED光源促进滇重楼药用部位生长、提高其药效成分具有重要的理论意义和应用价值。结果表明：1.有利于滇重楼生长的单质光是Y75和G100，有利于根茎总皂苷含量和产量提高的单质光是B150、G100和Y75， 组合光源OBG712、OW41最有利于根茎总皂苷的累积，OB24h和W16h有利于滇重楼生长和干物质累积，8h/d光照有利于根茎总皂苷的累积。2. 随着白、绿、黄和蓝光强的增加，叶片δ13C呈增加的趋势，δD呈降低的趋势；随着橙、黄光强的增加，叶片δ18O呈增加的趋势。与单质橙、蓝光比较，橙蓝组合光源叶片δ13C增加，但δ15N、δ18O低于单质蓝光。随着白光光期的增加，叶片δ15N、δ13C呈降低的趋势，δ18O呈增加的趋势，δD先降后增。3. G100、W200、OBG712、OB41、OW41、OB12h、W16h叶片光合作用较佳, Y75光系统Ⅱ反应中心活性和光能转换效率最高。4. W200、O100、OBG712、OB81、OW41、OB24h、W16h碳氮代谢较为协调和旺盛。5. B150、W200、O150、G200、R150、Y25、OBG721、OBG712、OB21、OW61、OB24h促长型激素含量和激素平衡状况较好。6.W150、B150、OB41解剖结构最优，W12h最利于气孔开放，橙光及其组合光源有利于叶片气孔发育，光合参数与气孔开放程度呈极显著负相关。7.W150、B150、G150、Y100、R50、O50有利于滇重楼对养分元素的吸收，OBG、OB、OW组合光源下滇重楼茎叶和根茎养分元素含量高于橙光，OB8h养分元素含量最高。筛选出的单质光、组合光源、光期可为滇重楼高产优质栽培提供技术支撑。