灰木莲叶片解剖结构与光合特性的关系研究  

Study on the Relationship Between Leaf Anatomical Structure and Photosynthetic Characteristics of Magnolia sumatrana var.glauca(Blume)Figlar&Noot.

作　　者：许伟兵 Xu Weibing(Dongjiang Forest Farm,Guangdong Province(Guangdong Dongjiang Forest Park Management Office)Heyuan,Guangdong 517465,China)

机构地区：[1]广东省东江林场广东东江森林公园管理处,广东河源517465

出　　处：《绿色科技》2023年第19期121-125,131,共6页Journal of Green Science and Technology

摘　　要：研究探讨了灰木莲(Magnolia sumatrana var.glauca Blume Figlar&Noot.)叶片发育过程中净光合速率与叶面积变化以及叶片解剖特性之间的关系。在灰木莲中,叶肉细胞在叶面积基础上,面向细胞间空气空间的表面积(SME)在全叶面积扩张(FLE)时已经相当大。然而,叶绿体在叶面积基础上面向细胞间空气空间的表面积(Sc),以及叶面积基础上的叶绿素和加氧酶含量在FLE后15~40 d达到最大值。在灰木莲中,内部CO_(2)转移电导(gi)在FLE后10 d略有增加,但在后期下降。gi对光合作用的限制在FLE时仅约占10%,但在FLE后约40 d增加至约30%。FLE后的较大gi限制可能是由于叶肉细胞壁厚度和每个叶绿体表面积的加氧酶含量增加,导致叶绿体中CO_(2)浓度降低。这些结果明确表明:(1)在灰木莲中,叶绿体的发育速度较慢,相对于叶肉细胞的扩增,在FLE后仍持续进行;(2)FLE后,灰木莲叶片的光合作用明显受到gi的限制。这些结果表明,灰木莲叶肉细胞的保护优先于有效的CO_(2)转移和叶绿体的快速构建。This study investigated the relationship between net photosynthetic rate and leaf area changes and leaf anatomical characteristics of Magnolia sumatrana var.glauca(Blume)Figlar&Noot during leaf development.In the Magnolia sumatrana var.glauca(Blume)Figlar&Noot,the surface area(SME)of mesophyll cells towards the intercellular air space on the basis of leaf area is already quite large during the whole leaf area expansion(FLE).However,the surface area(S c)of chloroplasts to the intercellular air space on the basis of leaf area,and the chlorophyll and Oxygenase content on the basis of leaf area reach the maximum value 15~40 days after FLE.In the Magnolia sumatrana var.glauca(Blume)Figlar&Noot,the internal CO_(2) transfer conductivity(g i)slightly increased 10 days after FLE,but decreased in the later stage.The limitation of g i on photosynthesis only accounts for about 10%at FLE,but increases to about 30% approximately 40 days after FLE.The greater g i limitation after FLE may be due to the increase of mesophyll cell wall thickness and the content of Oxygenase on the surface area of each chloroplast,leading to the decrease of CO_(2) concentration in chloroplasts.These results clearly indicate that:①in Magnolia sumatrana var.glauca(Blume)Figlar&Noot,chloroplast development is slower and continued after FLE compared to mesophyll cell expansion;②After FLE,the photosynthesis of the leaves of Magnolia sumatrana var.glauca(Blume)Figlar&Noot was significantly restricted by g i.These results indicate that the protection of the mesophyll cells of Magnolia sumatrana var.glauca(Blume)Figlar&Noot prioritizes effective CO_(2) transfer and rapid chloroplast construction.

关 键 词：灰木莲 叶片解剖 光合特性 

分 类 号：S688[农业科学—观赏园艺]