玉龙雪山不同海拔草血竭叶片形态与解剖结构的比较研究  

Comparison on Leaf Phenotypic and Anatomical Structures of Polygonum paleaceum along Altitudinal Gradients at Yulong Mountains

作　　者：王元元[1] 齐丹卉[2] 刘文胜[1,2] 梁文斌[1] 

机构地区：[1]中南林业科技大学生命科学与技术学院,长沙410014 [2]西南林业大学环境与工程学院,昆明650224

出　　处：《西北植物学报》2016年第1期70-77,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(31160048)

摘　　要：采用常规石蜡制片技术和显微观察方法,对生长于滇西北玉龙雪山3 000～4 600m之间9个不同海拔高度的草血竭（Polygonum paleaceum）叶片表型及解剖结构进行比较研究,其目的是揭示该植物对不同海拔环境条件的响应特征,进而探讨植物对全球气候变化的生态适应性。结果显示：（1）草血竭叶片长度、宽度、长宽比均与海拔呈显著负相关关系,其降幅分别达84.64%、74.87%和37.50%。（2）草血竭叶片为异面叶,由表皮、叶肉、叶脉三部分组成;表皮细胞单层,角质层厚;叶肉的栅栏组织具2层或3层细胞;叶脉中的维管束呈1圈不连续的环状排列。（3）叶片厚度、栅栏组织厚度、海绵组织厚度、主脉厚度、以及主脉中维管束的长度和宽度均与海拔呈显著正相关关系,增幅分别达38.32%、47.30%、47.39%、156.46%、173.51%及337.42%;上表皮厚度、下表皮厚度、叶片紧密度、叶片疏松度、栅海比以及维管束的个数与海拔梯度之间的相关性则均不显著。研究表明,随着海拔升高,草血竭叶片形态结构的改变主要是有利于植物降低蒸腾,增强储水性和提高光合效率。Leaves exhibit great phenotypic plastic in both morphology and anatomic structure,and are the most sensitive organ to environmental changes.In this study,leaves of Polygonum paleaceumliving at nine altitudes ranged from 3 000 to 4 600 min Yulong Mountains were sampled.Then the morphological and anatomical structures of these leaves were studied by the paraffin section method and microscopic techniques.The aim is to reveal the adaptive strategy of this plant to different altitudes.The results showed：（1）length,width,and ratio of length to width all decrease with rising altitude,the maximum decrease rates are84.64%,74.87% and 37.50%,respectively.（2）The leaves of this plant are bifacial,including epidermis,mesophyll and vein.The epidermis is single layer and has thicker cuticle;the palisade of mesophyll is composed by two to three layers of cells.The veins compose some vascular bundles which arrange by a discrete circle.（3）The thickness of the leaves,palisade tissue thickness,spongy tissue thickness and thickness of main vein,length of vascular bundles,and width of vascular bundles all increase with rising altitudes,the maximum increase are 38.32%,47.30%,47.39%,56.46%,173% and 337%,respectively.While the upper and lower epidermis,cell tense ratio,leaf loose degree,ratio of palisade to spongy tissue and number of vas-cular bundles did not correlate with altitudes significantly.In summary,this study showed the morphological and anatomical structures of P.paleaceumleaves would be changing with increasing altitudes,which would be good for plants to decrease transpiration,increase water conservation and photosynthesis ability.

关 键 词：草血竭 叶片 海拔梯度 表型特征 解剖结构 

分 类 号：Q944.56[生物学—植物学] Q944.3