不同光强下琼岛杨幼苗生长和光合特性  

Growth and photosynthetic characteristics of Populus qiongdaoensis seedlings under different light in⁃tensities

作　　者：饶丹丹 韩豫 吴二焕 陈彧 Rao Dandan;Han Yu;Wu Erhuan;Chen Yu(Hainan Academy of Forestry/Hainan Academy of Mangrove,Haikou 571100,China)

机构地区：[1]海南省林业科学研究院/海南省红树林研究院,海南海口571100

出　　处：《山西农业大学学报（自然科学版）》2024年第1期61-69,共9页Journal of Shanxi Agricultural University(Natural Science Edition)

基　　金：海南省自然科学基金项目(321QN366)。

摘　　要：[目的]本文旨在探究不同光照强度对琼岛杨(Populus qiongdaoensis)幼苗生长和光合特性的影响。[方法]以1.5年生琼岛杨幼苗为试验材料,设置全光100%(CK)、全光70%(RI70%)、全光40%(RI40%)和全光10%(RI10%),处理12个月后,分析不同光强对琼岛杨幼苗生长和光合特性的影响。[结果]成活率、地径增长量、叶片数、叶长、叶宽、叶面积和单叶质量均随着光强的减弱而降低,株高增长量和叶片数增长量呈先增后减趋势,RI70%和RI40%处理的琼岛杨幼苗的成活率、株高、地径和叶片数均显著高于RI10%处理;RI70%处理的根生物量、根生物量比和根冠比显著高于RI40%和RI10%处理,而RI70%和RI40%处理的根、茎、叶生物量和总生物量均显著高于RI10%;随着光照强度的降低,叶片叶绿素a、叶绿素b和总叶绿素含量逐渐增大,类胡萝卜素含量随之减小;净光合速率(Pn)随光照强度的减小而显著下降,在RI70%光强下琼岛杨幼苗叶片的Pn最大,分别是RI40%和RI10%的1.72倍和2.16倍;叶片数增长量与株高增长量、地径增长量呈显著正相关关系,净光合速率与类胡萝卜素含量(Car)和蒸腾速率(Tr)呈显著正相关,气孔限制值(Ls)与胞间CO_(2)浓度(Ci)和气孔导度(GS)呈显著负相关。[结论]琼岛杨幼苗能忍耐一定程度遮阴,适度遮阴可促进幼苗地上和地下部分的生长并提高其气体交换能力,但在弱光胁迫下幼苗难以成活和生长,相对光强70%下琼岛杨幼苗的适应性最强。[Objective]This study aimed to explore the effects of different light intensities on the growth and photosynthetic characteristics of Populus qiongdaoensis seedlings.[Methods]One and a half-year-old P.qiongdaoensis seedlings were used as experimental materials.Four light intensity treatments were set up:full light(100%,CK),70%full light(RI70%),40%full light(RI40%),and 10%full light(RI10%).After 12 months of treatment,the effects of different light intensities on the growth and photosynthetic characteristics of P.qiongdaoensis seedlings were analyzed.[Results]Survival rate,ground diameter growth,leaf number growth,leaf length,leaf width,leaf area,and single leaf mass all decreased with the reduction of light intensity.Stem height growth and leaf number showed an initial increase followed by a decrease trend.The survival rate,stem height,ground diameter,and leaf number of P.qiongdaoensis seedlings under RI70%and RI40%treatments were significantly higher than those under RI10%.The root biomass,root biomass ratio,and root-to-shoot ratio of RI70%treatment were significantly higher than those of RI40%and RI10%.RI70%and RI40%treatments resulted in significantly higher root,stem,leaf biomass,and total biomass compared to RI10%.With decreasing light intensity,leaf content of chlorophyll a,chlorophyll b,and total chlorophyll content gradually increased,while the content of carotenoids decreased.Pn significantly decreased with the decrease of light intensity.Under RI70%,P.qiongdaoensis sseedlings exhibited the highest Pn,which was 1.72 times and 2.16 times higher than those under RI40%and RI10%,respectively.Leaf number growth was significantly positively correlated with stem height growth and ground diameter.Pn was significantly positively correlated with carotenoid(Car)and transpiration rate(Tr).Stomatal limitation value(Ls)was significantly negatively correlated with Ci and GS.[Conclusion]P.qiong⁃daoensis seedlings can tolerate a certain degree of shade,and moderate shading can promote the growth of both aboveground and

关 键 词：琼岛杨 幼苗 光照强度 光合特性 

分 类 号：S718.43[农业科学—林学]