光强对杂交泡桐光合生理和荧光特性的影响  

Effects of light intensity on photosynthetic physiology and chlorophyll fluorescence characteristics of hybrid Paulownia

作　　者：王楠[1] 李芳东[1] 叶金山[1] 

机构地区：[1]中国林业科学研究院国家林业局泡桐研究开发中心,郑州450003

出　　处：《生态学杂志》2015年第11期3118-3124,共7页Chinese Journal of Ecology

基　　金："十二五"科技支撑项目(2012BAD01B0602)资助

摘　　要：以杂交泡桐毛白33(即TF33)及其回交一代(BC1(194)和BC1(192))为材料,通过人工模拟旷地、林窗和林下3种光环境(分别为全光照L0、50%全光照L1、25%全光照L2),比较了不同光强下泡桐回交一代及其亲本TF33叶片的光合能力和叶绿素荧光特性的差异。结果显示:(1)遮荫后杂交泡桐净光合速率(Pn)日变化曲线由"双峰"型变为"单峰"型,日平均Pn随遮荫程度增加显著降低(P<0.05)。L0条件下,BC1(194)和BC1(192)的日平均Pn未表现出杂种优势;L1条件下,BC1(192)和BC1(194)的日平均Pn杂种优势率(RH)分别为2.23%和3.67%;L2条件下,BC1(192)的日平均Pn高于TF33,但差异不显著,BC1(194)则表现为杂种劣势。(2)L0条件下,TF33的最大净光合速率(Pmax)和光饱和点(LSP)最大,光补偿点(LCP)和暗呼吸速率(Rd)最小;L1条件下,BC1(192)的Pmax、LSP和AQY最大,LCP和Rd最小;L2条件下,虽然BC1(194)和BC1(192)的Pmax低于TF33,但其LCP和Rd值也低于TF33。(3)L0条件下,TF33、BC1(194)和BC1(192)各荧光参数差异不显著;L1条件下,3个无性系的q P和q N差异显著,BC1(192)的热耗散最弱,光合能力最强;L2条件下,BC1(192)和TF33的q P差异不显著,BC1(194)与TF33差异显著,BC1(192)的Fv/Fm、F0和ETR与TF33、BC1(194)差异显著(P<0.05)。结果表明,TF33、BC1(194)和BC1(192)虽均对弱光有一定的调节适应机制,但在全光照下生长最为适宜,遮荫使植株的光合能力显著降低,光照不足成为其生长的决定性限制因子。在低光照(L1)条件下,BC1(194)和BC1(192)较其亲本TF33有光合优势。The purpose of this experiment was to compare the differences of leaf photosynthetic capacity and chlorophyll fluorescence characteristics between Paulownia backcross optimal plants （including BCI（194） and BC1（192）） and their parent TF33. Three light levels [ 100% （L0）, 50% （L1 ） and 25% （L2） of natural sunlightl were conducted to simulate the light conditions of forest opening, forest gap and understory, respectively. The results showed that： （1） The diurnal vari- ation of net photosynthetic rate （P.） changed from bimodal pattern to unimodal type curve after shading, and the average daily Pn decreased significantly with inerease of shade degrees （P〈 0.05）. P. of BC1（194） and BC1（192） showed no significant advantage under Lo. But the P trans- gressive heterosis of BC1（192） and BC1（194） were respectively 2.23% and 3.67% under L1. BCl（192） had no remarkable advantage in Pn compared to TF33, while BC1（194） showed hybrid weakness under L2. （2） TF33 had the highest maximum net photosynthetic rate （Pmax） and light saturation point （LSP）, but the lowest light compensation point （LCP） and dark respiration rate （Rd ） un- der L0 among three clones. Under the condition of L1 , P LSP and apparent quantum yield va- lue （AQY） of BC1（192） were the highest, while LCP and Rd were the lowest. Although Pmax of BC1（194） and BC1（192） in L2 were lower than that of TF33, LCP and Rd were lower, too. （3） The differences in fluorescence parameters were not significant among TF33, BC1（194） and BC1（ 192） un- der L0. qP and qN were significantly different among three clones and BC1（192） had the weakest heat dissipation but strongest photosynthetic capacity under L1. BC1（192） had no significant differ- ence in qP with TF33, while BC1〈194） had significant difference with TF33 under L2. At the same time, BC1（192） had significant difference in Fv/Fm, Fo, ETR with BC1（194） and TF33 （P〈0.05）. Our results indicat

关 键 词：杂交泡桐 光照条件 光合生理特性 叶绿素荧光参数 

分 类 号：S792.43[农业科学—林木遗传育种]