弱光胁迫对甘草质量影响的研究

【作者】 侯俊玲；

【导师】 王文全；

【作者基本信息】 北京中医药大学 ， 中药学， 2010， 硕士

【摘要】 弱光对植物生长和次生代谢产物积累的影响非常大。本项目拟以自然光辐射光源(Control)为对照系,设置三个梯度的人工调控弱光胁迫系统(LLI1、LLI2、LLI3),采用生物物理学原理和化学成份分析相结合的研究方法,通过对甘草(Glycyrrhiza uralensis Fisch.)生长、产量、光合生理、主要物质组分含量等指标的监测,研究弱光胁迫与甘草生长及药材质量的相关性,探索弱光胁迫对甘草酸、甘草苷等有效成分的形成和积累的影响,揭示弱光胁迫因子对甘草产量和质量的作用机制,为人工培育优质甘草和有效利用土地资源奠定理论和技术基础。主要研究结果如下：1.弱光胁迫对甘草生长及药材产量具有显著的影响：弱光胁迫在植株生长初期对株高和复叶促进较多,但生长后期各组差异不大；弱光胁迫越强,可导致叶面积越大、气孔密度越大、根粗度越细,须根数越少、叶片厚度越薄；此外,弱光胁迫对甘草干重影响初期不显著,但后期对干重的影响明显下降。2.弱光胁迫对甘草植株光合生理特性的影响：弱光胁迫下各组的净光合速率Pn、光化学效率Fv/Fm、光化学猝灭效率qP、PSⅡ的非循环光合电子传递速率ETR等均下降,与光照强度呈正相关关系,与自然光对照组相比较,LLI3下降最多；弱光胁迫各组植株的叶绿素a和b的总量增加,与自然光对照组形成显著差异,但对于叶绿素a与b的比值各组之间没有差异。3.弱光胁迫对甘草活性成分含量的影响：在本论文研究范围内,弱光胁迫可以促进甘草酸、甘草苷、总黄酮、总皂苷含量浓度的提高,并且其含量浓度随着弱光胁迫的增强和处理时间的延长而升高；弱光胁迫各组的多糖含量浓度先降低后升高,但自然光对照组含量浓度持续下降；自然光对照组的灰分含量呈下降趋势,弱光胁迫下,LLI1组的灰分先升高后下降,LLI2组的灰分呈下降趋势,LLI3组的灰分呈上升趋势；弱光胁迫各组的酸不溶灰分含量在试验初期均与自然光对照组差异不显著,试验后期升高。4.弱光胁迫对甘草酸和甘草苷净增值的影响：自然光对照组和弱光胁迫各组的甘草酸、甘草苷含量浓度与干重呈负相关关系。但甘草整个植株的甘草酸、甘草苷的净含量并不受光照强度的影响,也不随时间变化而改变。更多还原

【Abstract】 The growth and. secondary metabolites of medicinal plants have been affected greatly by the low light intensity. The test was designed by solution cultivated one year-old rhizome seedlings of one medicinal species-liquorice (Glycyrrhiza uralensis Fisch) were grown under three low irradiances,200,100, and 50 mmol m-2 s-1 (showed as LL1, LL2 and LL3) for 135 days. Control plants were cultured under natural light condition. Effects of low light intensity on growth, yield, photosynthesis and secondary metabolites (glycyrrhizic acid and liquiritin) were investigated. Based on the growth and quality of G. uralensis were affected by the low light intensity, the regulation technical foundation of cultured G. uralensis maybe used in the agroforestry systems. The major results are followed:1. The growth and medicinal materials yield were affected greatly by the low light intensity:The plant height and compound leaf were increased at the binging and were not affected at the late in plant growth by the low light intensity. Low light intensity stress decreased root size, fibre quantity and leaf thickness, but increased leaf area and stomatal density, The dry weight were not affected significantly at early days and decreased at the late by the low light intensity.2. Effect of low light intensity on photosynthesis physiology characteristic:Net photosynthetic rate (Pn), photochemical efficiency (Fv/Fm), photochemical quenching (qP) and electron transport rate (ETR) decreased with low light intensity decrease. The.most of decrease degree was observed at LLI3 treatment compared to the Control. However, low light intensity significantly increased total chlorophyll concentrations, while did not affect chlorophyll a/b.3. Effect of low light intensity on active components contentAccumulation of glycyrrhizic acid, liquiritin, total flavone and total saponin in root significantly increased with low light intensity down and treatment time prolong. Polysaccharid content decreased and then increased with low light intensity stress time, while decreased continually in natural light condition. Ash content of LLI1 increased and then decreased, decreased in LLI2, and increased in LLI3, compared with ash content of LLI1 decreased. There was not significantly in acid no dissolve ash content between low light intensity stress and the Control at the beginning, and increased at the late. 4. Effect of low light intensity on net add values of glycyrrhizic acid and liquiritin in rootConcentrations of glycyrrhizic acid and liquiritin were negatively correlated with root biomass in low light intensity and natural light condition. Net content of glycyrrhizic acid and liquiritin in the whole plants have not been affected by light intensity and treatment time.更多还原