林业科学2018，Vol.54Issue(2)：179-185,7.DOI:10.11707/j.1001-7488.20180221
去遮荫后东北红豆杉幼苗和幼树光合特性对比
Photosynthesis and Chlorophyll Fluorescence Characteristics of Seedlings and Saplings of Taxus cuspidata After Removing Shade
摘要
Abstract
[Objective] In this study,Photosynthesis and chlorophyll fluorescence characteristics of seedling and sapling leaves of Taxus cuspidata were studied to explore the reasons for the photoinhibion of seedlings after removal of shading,which provide would theoretic basis for the development of Taxus cuspidata cultivation in Northeast China.[Method]Seedlings and saplings of Taxus cuspidata grown under shade condition (approximately 40％ of the natural light intensity) were taken as the materials.They were moved to full sunlight for 28 days before the experiment was carried out.Then differences of pigment,photosynthesis and chlorophyll fluorescence characteristics of seedling leaves and sapling leaves were measured.[Result] The result showed that there was no significant difference between seedling leaves and sapling leaves in chlorophlly content.Sapling leaves had a higher content of cartotenoid and a lower value of Chl/Cars significantly.The maximum photosynthetic rate of seedling leaves was only 70％ of that of sapling leaves after 28-day full sunlight.Seedling leaves had a lower light compensation point and light saturation point,but apparent quantum yield of photosynthesis (AQY) was higher.In this case,more excessive energy was produced in seedling leaves under full sunlight condition.Meanwhile,compared within sapling leaves,carboxylation efficiency (CE),regeneration rate of RuBP and Amax in seedling leaves were lower as well.Theses results indicated that the activity of Rubisco enzyme and the assimilation ability of CO2 in seedling leaves were relatively lower.Seedling leaves and sapling leaves of T.cuspidata showed different photosynthetic responses to high light intensity in a short period.The sapling leaves reached the maximum photosynthetic rate in about 25 min under high light,while seedling leaves reached the maximum photosynthetic rate in about 50 min.From low light to high light,actual photochemical efficiency (ФPSⅡ) and non-photochemical quenching (NPQ) of sapling leaves reached their maximum values in a shorter time as compared with those of seedling leaves.In addition,the ФPSⅡ of seedling leaves reduced with the increase of PFD,while that of sapling leaves decreased slightly.Moreover,NPQ of sapling leaves reached a relatively higher level with the increase of PFD,while seedling leaves attained their maximum value with a low light intensity.[Conclusion] A lower photosynthetic rate of the seedlings resulted in relatively excessive light energy,which made seedling leaves susceptible to photoinhibition after changing to full sun light.关键词
东北红豆杉/光合速率/叶绿素荧光/幼苗Key words
Taxus cuspidata/photosynthesis/chlorophyll fluorescence/seedling分类
农业科技引用本文复制引用
李威,杨德光,牟尧,杨自超,王雪蓉,刘彤彤,李淑敏..去遮荫后东北红豆杉幼苗和幼树光合特性对比[J].林业科学,2018,54(2):179-185,7.基金项目
林木遗传育种国家重点实验室(东北林业大学)开放基金项目(K2013206) （东北林业大学）
东北农业大学“青年才俊”项目(17QC36). （17QC36）
