光照强度对3种大型卷瓣凤梨叶片解剖结构及光合色素含量的影响  

Effects of Light Intensity on the Leaf Anatomical Structure and Photosynthetic Pigments of 3 Giant Alcantarea Species

作　　者：李萍 LI Ping(Shanghai Chenshan Botanical Garden, Shanghai, 201216, China)

机构地区：[1]上海辰山植物园,上海201216

出　　处：《西北植物学报》2020年第12期2065-2074,共10页Acta Botanica Boreali-Occidentalia Sinica

基　　金：上海市绿化与市容管理局科学技术项目(G182423)。

摘　　要：为了明确卷瓣凤梨属植物不同种类对环境光强的适应性差异,该研究以3种大型卷瓣凤梨属植物的成熟植株为研究对象,在全光照(CK)、40%光照(S_(40))、10%光照(S_(10))3种环境下生长近4个月后进行叶解剖结构特征的观测以及光合色素含量的测定。结果表明:(1)3种卷瓣凤梨的叶解剖结构大致相似,叶的上下表皮均由单层细胞组成,且细胞内壁加厚;表皮层发达;表皮细胞下为多层的含水组织;叶肉组织中分化出明显的栅栏组织和海绵组织,栅栏组织呈独特的拱状排列,下面形成椭圆形至长圆形的气腔,内含丰富的海绵组织,气腔与叶下表面的气孔下室连接,从而有利于叶片内部的气体交换,保证在叶基部常年处于积水的环境下叶内部仍有充足的气体用于光合作用。(2)环境光强对卷瓣凤梨属植物叶解剖结构特征的影响因种而异,其中‘格拉齐’对环境光强的变化较为敏感,其叶片厚度、角质层厚度、海绵组织占比以及栅海比在不同光强下产生了显著变化,而‘红帝’和‘优雅’除角质层厚度发生显著变化外其余指标均未发生显著变化;3种卷瓣凤梨叶气孔密度在不同光照处理下均几乎没有发生变化,且‘红帝’和‘优雅’的叶气孔密度较为接近并均显著高于‘格拉齐’,表明不同种类的卷瓣凤梨在叶解剖结构上存在遗传上的差异,且性状较为稳定。(3)环境光强对3种卷瓣凤梨叶片光合色素含量的影响显著,且不同种类卷瓣凤梨对光强变化的响应存在差异,在全光照(CK)和40%光照(S_(40))处理下3种卷瓣凤梨的Chl_(a)/Chl_(b)在2.73~3.03之间,接近阳生叶的特征,而在10%光照(S_(10))处理下Chl_(a)/Chl_(b)均下降,其中‘格拉齐’最低为2.53,接近阴生叶的比值。研究发现,3种卷瓣凤梨对于强光的耐受性表现为帝王卷瓣凤梨(红叶型)>‘优雅’卷瓣凤梨>卷瓣凤梨格拉齐,对于弱光环境的表现则相反;帝王In order to define the adaptability to different light intensities in genus Alcantarea,mature plants of 3 giant species of Alcantarea were treated under full sun light(CK),40%light(S_(40))and 10%light(S_(10))for 4 nearly months.The variation on leaf anatomy structure and the amounts of photosynthetic pigments in the leaf of different treatments were measured and detected.The results show that:(1)the features of leaf anatomic structure of 3 Alcantarea species are similar,with single layer of small epidermal thick-walled cells on both surfaces,and the epicuticular stratum is well-developed.A multi-cellular aquiferous hypodermis is formed beneath the epidermal cells,palisade parenchyma(PP)and spongy parenchyma(SP)are well differentiated in mesophyll,and the PP is arranged in arches,an aeration channel with cross sections shaped in ellipse or oblong formed under the PP and filled with SP.These air channels are connected to the sub-stomatic chambers on the abaxial surface,which contribute to the gas exchange in the mesophyll,ensuring that there is sufficient gas for photosynthesis although the leaf base sits in water year around.(2)The effects of environmental light intensity on leaf anatomical structure of Alcantarea varied with species,A.glaziouana is more sensitive to the changes of light intensity,with significant differences on the leaf thickness,cuticle thickness,the proportion of spongy parenchyma and the ratio of palisade and spongy under different light intensity,as for A.imperialis and A.‘Grace’,except for the cuticle thickness,the other characteristics did not change significantly.The stomatal density on the leaf of 3 Alcantarea species has almost no change under different light treatments,and the stomatal density of A.imperialis and A.‘Grace’was similar and significantly higher than that of A.glaziouana,indicating the difference of anatomical features among species was determined genetically,and relatively stable.(3)Light intensity had the significant effect on the photosynthetic pigments of 3 Alca

关 键 词：卷瓣凤梨属 光照 气孔 叶片解剖 光合色素 

分 类 号：Q944.56[生物学—植物学]