不同光强对柔毛淫羊藿生长特性和淫羊藿酮醇苷含量的影响

Effects of Different Light Intensities on Growth Characteristics and Content of Icarrin Flavonol Glycosides of Epimedium pubescens

目的:分析不同光照强度(以下简称光强)对柔毛淫羊藿(“贵同柔毛1号”品种)生长、光合特性及有效成分含量的影响,为确定适宜的栽培生产措施提供参考。方法:设置L1[(36.4±5.0)μmol·m^(–2)·s^(–1)]、L2[(91.0±5.0)μmol·m^(–2)·s^(–1)]、L3[(145.6±5.0)μmol·m^(–2)·s^(–1)]和L4[(200.2±5.0)μmol·m^(–2)·s^(–1)]4种光强,连续处理40 d,分别在10、20、30、40 d测定生长发育指标(分枝数、叶片数),于第40天测定处理期间同期萌发且已经成熟的叶片的光合生理指标[净光合速率(P_(n))、蒸腾速率(T_(r))、气孔导度(G_(s))和胞间CO_(2)浓度(C_(i))]及淫羊藿黄酮醇苷类成分(朝藿定A、朝藿定B、朝藿定C、淫羊藿苷)含量。结果:生长指标方面,随着光强从L1增大至L4,总分枝数及总叶片数显著增加,快速增加期出现在20~40 d,其中,L1~L3处理均在30 d时增幅最高,分别为48.52%、70.00%和83.53%,L4处理下在20 d达到最高增幅165.00%,约为L3处理的2倍;光合生理指标方面,叶绿素含量整体呈小幅下降趋势,P_(n)、T_(r)、G_(s)整体呈上升趋势,C_(i)整体呈下降趋势;药用成分方面,淫羊藿黄酮醇苷类成分质量分数先增加后基本持平,L3处理下达到最高,为(61.49±1.00)mg·g^(–1)。结论:柔毛淫羊藿在强光下的分枝数增加、P_(n)增加和淫羊藿黄酮醇苷类成分含量增加的趋势和其他淫羊藿属物种一致,但对更高光强的适应性和耐受性显著高于其他物种。

Objective:To determine appropriate cultivation and production measures by analyzing the effects of different light intensities on the growth,photosynthetic characteristics,and bioactive content of Epimedium pubescens(Cultivar Guitong Roumao No.1).Methods:Four light intensities were set,including L1[(36.4±5.0)μmol·m^(–2)·s^(–1)],L2[(91.0±5.0)μmol·m^(–2)·s^(–1)],L3[(145.6±5.0)μmol·m^(–2)·s^(–1)],and L4[(200.2±5.0)μmol·m^(–2)·s^(–1)],and the treatment lasted for 40 d.Growth parameters(the number of branches and leaves)were determined at 10,20,30,and 40 d,respectively.In 40 d,photosynthetic parameters[net photosynthetic rate(P_(n)),transpiration rate(T_(r)),stomatal conductance(G_(s)),and intercellular CO_(2) concentration(C_(i))]and the icariin flavonol glycoside content(epimedin A,epimedin B,epimedin C,and icariin)of leaves that germinated and matured at the same time during treatment were determined.Results:In terms of growth parameters,with the increase in the light intensity from L1 to L4,the total number of branches and leaves increased significantly.The rapid increase period occurred in 20-40 d,wherein the treatment of L1-L3 had the highest increase in 30 d,which increased by 48.52%,70.00%,and 83.53%,respectively.Notably,the L4 treatment reached the highest increase of 165.00%in 20 d,which was twice that of the L3 treatment.In terms of photosynthetic characteristics,chlorophyll content showed a slight downward trend from L1 to L4,while P_(n),T_(r),and G_(s) showed an overall upward trend and C_(i) showed a decreasing trend.The icariin flavonol glycoside content increased gradually and then remained unchanged from L1 to L4.The total content reached the highest level in the L3 treatment,which was(61.49±1.00)mg·g^(–1).Conclusion:Under highlight treatment,the number of branches and leaves,Pn,and the icariin flavonol glycoside content reveal an increased trend,which is consistent with those of other Epimedium species.However,the adaptability and tolerance to higher light intensity for cultivar E.pubescens are significantly higher,which is significantly different from other Epimedium species.