独一味幼苗生理特性和次生代谢产物对遮阴的响应

Response of Seedling Growth and Secondary Metabolites in Lamiophlomis rotata Seedlings to Different Shade Conditions

目的：研究遮阴处理对独一味幼苗生长和化学成分的影响,探索独一味对光照环境变化的适应机制,为幼苗期合理管理提供科学依据。方法：以二年生独一味幼苗为研究对象,测定遮阴处理处理后幼苗形态指标（叶面积、根长）,生理指标[丙二醛（MDA）,超氧化物歧化酶（SOD）活性等]和主要次生代谢产物8-O-乙酰山栀苷甲酯和山栀苷甲酯含量。结果：遮阴处理显著降低了独一味幼苗根长、单株叶片数目、叶面积、生物量和根冠比（P〈0.05）,并显著增加了地上叶部分的生物量分配,全光照使更多的生物量分配至地下根。遮阴处理不仅显著降低了独一味叶片中叶绿素、脯氨酸和可溶性糖的含量（P〈0.01）,还极显著地增加了叶片中过氧化物酶的含量（P〈0.01）。遮阴处理显著降低了独一味根及地上部分中8-O-乙酰山栀苷甲酯的含量及山栀苷甲酯和8-O-乙酰山栀苷甲酯总含量（P〈0.05）。结论：遮阴管理显著增加了独一味地上即药用部位的生物量;高原光照可能为独一味带来逆境效应,有利于独一味生物量积累,并促进2种环烯醚萜苷化合物的代谢,因此育苗管理应注意控制遮阴强度和时间。二年生独一味幼苗中化学成分含量符合2015年版《中国药典》规定,表明通过栽培可以满足资源供给。

Objective： To investigate the effect of shading treatment on growth,physiological and secondary metabolites response of Lamiophlomis rotate,in order to explore its adaptation mechanism to shade environment,and provide a theoretical basis for seedling management. Method： Two-year-old L. rotate plants were given shading treatment,with 40% of light intensity of sunshine. Morphological indicators,such as the number of leaves,leaf area and root length per plant,were recorded. Physiological parameters were measured,including malondialdehyde（MDA） content,superoxide dismutase（SOD） activity,peroxidase（POD） activity,content of proline,catalase（CAT） activity,soluble sugar,soluble protein content and chlorophyll content.Chemical components of L. rotata were measured,including C（19）H（28）O（12） and C（17）H（26）O（11）. Result： Shade conditions significantly reduced root length,the number of leaves,leaf area,the biomass and root-top ratio of L. rotate. The underground biomass was increased in full sunlight treatment. Shading treatments not only significantly decreased chlorophyll content,content of proline and soluble sugar,but also significantly increased POD activity. Shading treatment significantly decreased both the content of C（19）H（28）O（12） and the total content of C（17）H（26）O（11） and C（17）H（26）O（11）（P 〈 0. 05）. Conclusion： The results indicated that shading treatment could promote biomass allocation for pharmaceutical use,and sunlight on plateau may play the role of adversity factor,which could increase the content of C（17）H（26）O（11） and C（17）H（26）O（11）. We shall pay attention to controlling suitable shading time for nursery management.The results of this study show that the 2-year L. rotate seedling tablets conform with the provisions for L. rotata cultivation in pharmacopoeia,