遮荫对青钱柳苗期光合特性和生长的影响  

Influence of Shading on Photosynthetic Characteristics and Growth of Cyclocarya paliurus Seedlings

作　　者：李雨霏 郭鹏飞 张小燕 邓波 Li Yufei;Guo Pengfei;Zhang Xiaoyan;Deng Bo(Anhui Agricultural University,Hefei 230037,P.R.China)

机构地区：[1]安徽农业大学,合肥230022

出　　处：《东北林业大学学报》2021年第8期6-10,共5页Journal of Northeast Forestry University

基　　金：国家自然科学基金项目(31800528);2019年安徽农业大学国家级大学生创新创业训练计划项目(dg193702)。

摘　　要：以2年生青钱柳为试验材料,设置为3个遮荫处理(A 1:全光,A 2:遮光50%,A 3:遮光80%),研究不同光照处理对青钱柳叶片的光合-光响应曲线、荧光参数、生长的影响。结果表明:随着遮荫强度的增大,温度下降且空气相对湿度增大,青钱柳的最大净光合速率(P_(nmax))、光饱和点(L_(s,p))、光补偿点(L_(c,p))、暗呼吸速率(R_(d))均显著下降。与A_(1)处理相比,A_(2)处理并未明显影响青钱柳的光合速率。在弱光环境下,青钱柳叶中总叶绿素质量分数和叶绿素b的比例明显增大,光能利用效率明显提高,反映叶片光合系统实际光能利用效率的荧光参数:光化学猝灭系数(Q_(p))、非光化学猝灭系数(Q_(n,p))、电子传递速率(υ_(e))均受遮荫处理的显著影响。A_(2)处理的青钱柳株高生长最高,A_(3)处理株高、地径生长均受到明显抑制。由此可见,青钱柳在生长前期具有一定的耐阴性,且通过光合和形态的可塑性以适应适度遮荫。With the two-year-old seedlings of Cyclocarya paliurus,and three shading treatments(A1:full light;A2:50%shading;A3:80%shading)were set to study the effects of light intensity on photosynthesis-light response curve,fluorescence parameter and growth.Our results indicated that the air temperature was decreased while the relative humidity was increased with the enhanced shading levels.The maximum net photosynthetic rate(P_(nmax)),the light saturation(L_(s,p)),the light compensation(L_(c,p)),and the dark respiration(R d)were all significantly decreased.However,the maximum net photosynthetic rate was not significantly influenced for 50%shading as compared to full light.The total chlorophyll content and the chlorophyll b ratio in leaves of C.paliurus were significantly increased in the lower light environment.In addition,the light use efficiency was significantly increased under the lower light condition,as shown by the significantly influenced fluorescence parameter(Q_(p),Q_(n,p) and υ_(e)),which can reflect the actual light use efficiency of photosynthetic system.The highest tree height growth was detected in 50%shading treatment,while both the tree height and base diameter growth were significantly inhibited under the treatment A3.Therefore,the C.paliurus have a certain degree of shade tolerance in the early stage of growth,and the C.paliurus can adapt the moderate shading through the photosynthetic and morphological plasticity.

关 键 词：青钱柳 遮荫 光响应曲线 荧光参数 

分 类 号：Q945.3[生物学—植物学]