锥栗不同树体结构对光的响应  

Effects of different tree shapes on light use in Castanea henryi

作　　者：范晓明[1] 袁德义[1] 杨斐翔 田晓明[3] 唐静 张旭辉[1] 朱周俊 

机构地区：[1]中南林业科技大学经济林培育与保护教育部重点实验室,长沙410004 [2]湖南应用技术学院,常德415000 [3]湖南省森林植物园,长沙410000

出　　处：《生态学报》2015年第22期7426-7434,共9页Acta Ecologica Sinica

基　　金：国家"十二五"科技支撑计划课题"板栗和锥栗高效生产关键技术研究与示范"(2013BAD14B04);湖南省研究生科研创新项目(CX2014B331)

摘　　要：为探讨锥栗树体结构与光能利用的关系,从而为栗园标准化管理及优质丰产栽培提供科学依据,以8年生华栗4号锥栗为试材,研究了锥栗不同树体结构的相对光照强度、光合作用及叶绿素荧光参数,阐述了不同树体结构对锥栗光合性能及产量的响应。研究结果表明:(1)3种锥栗树形(开心形、小冠疏层形及自然圆头形)树体的净光合速率日变化(P_n)呈双峰曲线型峰值均出现在10:00,次峰值均在14:00,其中以开心形树体10:00的P_n最大为9.97μmol m^(-2)s^(-1);(2)锥栗不同树体结构的光合参数差异显著,开心形锥栗树体叶片的最大光合速率和光饱和点显著高于其他处理,而光补偿点和暗呼吸速率显著低于小冠疏层形和对照处理,表明开心形树体的光合性能较强;(3)叶绿素荧光参数显示开心形锥栗树体电子传递速率(ETR)显著高于其它两种树形及对照;(4)锥栗不同树体结构光合性状与产量的相关分析表明单株产量与P_n、蒸腾速率(G_s)、PSⅡ潜在光化学效率(F_v/F_0)、ETR及叶绿素含量呈极显著正相关。综上,开心形锥栗树体在光能利用效率方面优于自然圆头形和小冠疏层形有利于锥栗增产。Eight-year-old Castanea henryi cv. Huali 4 （Fagaceae） trees were studied in order to explore the relationship between tree shape and light use by C. henryi, and provide scientific advice on the cultivation and management of this species. An illuminometer, a chlorophyll meter and a portable photosynthesis system were used to measure relative light intensity in different tiers of the canopy, and the diurnal course of ecophysiological and photosynthetic parameters were measured to ascertain the effects of different tree forms on the photosynthetic performance and yield of C. henryi. The results showed that ： 1 ） the relative light intensities of the three tree shapes roundhead） created by specific training and pruning regimes were all （open center, small and sparse canopy, and natural significantly higher than the control （trees not trained or pruned, but left to grow naturally ） for all the canopy positions. Relative light intensity followed the same trend, regardless of canopy position （ open center shape 〉 small and sparse canopy 〉 natural roundhead shape）. The relative lightintensity in the outer layer of the open center shape was highest （93.89%）, This was 10.34% higher than the value for the small and sparse canopy shapes, 23.29% higher than in the natural roundhead shape, and 41.08% higher than the control. These results indicated that C. henryi received more light when it had an open center shape. Diurnally, the net photosynthetic rate （P,） for C. henryi leaves taken from different shaped leaves on the open center shaped trees （9.97 μmol m-2s-1） was higher trees had two peaks at 10：00 and 14：00. The P. for than the values for the other two shapes and the control. 2） Some photosynthetic parameters differed significantly among the tree shapes. The maximum P and the light saturation point in trees with the open center shape were higher than the values recorded for the other tree shapes. However, the CO2 compensation point and dark respiration rate for leaves on the ope

关 键 词：锥栗 树体结构 光合特性 净光合速率 光合电子传递速率 

分 类 号：S664.2[农业科学—果树学]