摘要
以2年生紫椴(Tilia amurensis Rupr)幼苗为材料,设定4个遮光度,对处理后叶片净光合速率日变化、光响应参数、叶绿素荧光参数等进行测量和系统分析。结果表明,随遮光度的增加,幼苗净光合速率、气孔导度、蒸腾速率和水分利用效率先升高后降低,胞间CO 2浓度先降低后升高;轻度遮光下,幼苗光响应参数光饱和点、最大净光合速率显著提升,光补偿点和暗呼吸速率降低;随着遮光度的增加,紫椴的光系统Ⅱ量子效率(Fv/Fo)和最大光化学效率(Fv/Fm)值逐渐升高;能量分配比例参数中吸收的光能被反应中心捕获的量子产量(φPo)、激子被反应中心捕获后促进电子传递到电子传递链中超过Q A的电子受体的激子与促进Q A还原激子的比值(Ψo)、反应中心所吸收的光能应用于电子传递的量子产量(φEo)逐渐增加,而热耗散的量子产量(φDo)逐渐减少;光系统Ⅱ比活性参数中单位反应中心所吸收的能量(ABS/RC)、单位反应中心所捕获的应用到还原Q A的能量(TRo/RC)和单位反应中心耗散掉的能量(DIo/RC)值随着遮光度的增加逐渐下降,单位反应中心所捕获的应用到电子传递的能量(ETo/RC)值逐渐增加。紫椴叶绿素总量随着遮光度的增加而升高,叶绿素a/b值降低。结合隶属函数分析,轻度遮光下,紫椴幼苗叶绿素含量增加,日平均净光合速率和最大净光合速率最高,光合能力强,说明轻度遮光下有利于提升幼苗的光合特性,促进幼苗生长。
Four kinds of shading measures were set for the seedlings of the two-year-old Tilia amurensis Rupr and the daily changes of net photosynthetic rate,light response parameters and chlorophyll fluorescence parameters after treatments were measured and analyzed systematically.The results showed that with the increase of shading degree,the net photosynthetic rate,stomatal conductivity,transpiration rate and water use efficiency of the seedlings increased at first and then decreased,and the intracellular CO2 decreased at first decreased and then increased;Under light shading,seedling light response parameters light saturation point,maximum net photosynthetic rate were significantly increased,light compensation point and dark respiration rate were decreased;With the increase of opacity,the ratio of Fv/Fo and Fv/Fm of Tilia amurensis Rupr increased gradually;The energy distribution ratio parametersφPo,Ψo,φEo gradually increased whileφDo decreased gradually;PSⅡspecific activity parameters ABS/RC,TRo/RC and the value of DIo/RC gradually decreased as the opacities increased,and the value of ETo/RC gradually increased;The total amount of chlorophyll in Tilia amurensis Rupr increased with the increase of opacities,and the ratio of chlorophyll a/b decreased.Combined with the analysis of membership function,it was considered that various indicators indicated that under the shade of mild light,the chlorophyll content of Tilia amurensis Rupr increased,the average daily net photosynthetic rate and maximum net photosynthetic rate were the highest,and the photosynthesis ability was strong,which indicated that the light shading was beneficial to enhance the photosynthetic characteristics of seedlings and promote their growth.
作者
刘兴
杨晓
赵丹
金梦然
史宝胜
LIU Xing;YANG Xiao;ZHAO Dan;JIN Meng-ran;SHI Bao-sheng(College of Landscape Architecture and Tourism,Hebei Agricultural University,Baoding 071000,China)
出处
《新疆农业大学学报》
CAS
2019年第1期35-42,共8页
Journal of Xinjiang Agricultural University
基金
河北省林业科学研究院项目(17226320D)
河北省林业厅项目(1704487)
关键词
紫椴
幼苗
遮光
光合作用
叶绿素荧光
叶绿素含量
Tilia amurensis Rupr
seedling
shade
photosynthesis
chlorophyll fluorescence
chlorophyll content
