摘要
【目的】分析兰科植物营养器官结构对喀斯特生境的适应特性和不同兰科植物响应生境异质的生存策略,为兰科植物研究、保护与发展提供理论支持和参考依据。【方法】以贵州北盘江喀斯特地区6种不同生活型兰科植物的叶、假鳞茎、根为研究对象,采用石蜡切片法进行结构观察并测量相关指标,数据分析采用描述性和方差分析、相关性分析和主成分分析。【结果】(1)不同兰科植物结构特征间存在显著差异,丘北冬蕙兰、莎叶兰、兔耳兰和单叶石仙桃均为等面叶,叶片较薄;栗鳞贝母兰与梳帽卷瓣兰叶片为异面叶,有栅栏组织和海绵组织的分化,叶片较厚。(2)假鳞茎主要由表皮、基本组织和维管束组成,地生兰基本组织细胞较小,维管束密度大;附生兰基本组织细胞较大,储水结构较发达。(3)地生兰根被和皮层较厚,根被细胞排列紧密,皮层细胞小层数多;附生兰根被与皮层较薄,皮层细胞较大。(4)叶片下表皮厚度与叶片厚度、叶维管束直径、叶肉厚度、叶脉厚度呈极显著(P<0.01)正相关,叶肉厚度与下角质层厚度、假鳞茎维管束直径呈显著(P<0.05)负相关;假鳞茎直径和表皮厚度、假鳞茎维管束数量、假鳞茎横截面积呈极显著正相关,假鳞茎维管束直径占比与假鳞茎直径、表皮厚度、假鳞茎维管束数量、假鳞茎横截面积均呈极显著负相关;根的各指标间呈极显著正相关,根直径、根被厚度和皮层厚度与根维管束直径占比呈极显著负相关。【结论】兰科植物根部结构具有相对稳定的趋同适应性,叶片和假鳞茎结构间相互促进协调,是兰科植物响应干旱喀斯特环境的重要结构。
[Objective]The purpose of this study is to elucidate the adaptive traits of the vegetative organ structure of Orchidaceae to Karst habitats,in order to reveal the survival strategies of different orchid species in response to habitat heterogeneity,and to provide theoretical support and reference for the research,protection,and development of orchid species.[Methods]Investigation was conducted on the structure of leaves,pseudobulbs,and roots of six Orchidaceae species varying in life forms in the Karst region of the Beipan River,Guizhou,China.The paraffin section technique was employed to examine the structure and quantify relevant parameters.Descriptive and variance analysis,correlation analysis,and principal component analysis were employed for data analysis.[Results](1)There were significant differences in structural characteristics among different orchid species.Cymbidium qiubeiense,Cymbidium cyperifolium,Cymbidium lancifolium,and Pholidota leveilleana had isofacial leaves with thin leaves.The leaves of Coelogyne flaccida and Bulbophyllum andersonii were heterofacial and thicker with palisade tissue and spongy tissue differentiation.(2)Pseudobulbs were mainly composed of epidermis,basic tissue,and vascular bundle.The cells of the basic tissue were small and the density of the vascular bundle was high.The basic tissue cells of the pseudobulbs of epiphytic orchid were larger and the water storage structure was more developed.(3)The root coat and cortex of the ground orchid were thick,the root coat cells were closely arranged,and the cortical cells had many small layers.The rhizome and cortex of epiphyte orchids were thin,and the cortical cells were large.(4)The thickness of the lower epidermis of the leaves was significantly positively correlated with leaf thickness,leaf vascular bundle diameter,leaf flesh thickness,and leaf vein thickness(P<0.01),while leaf flesh thickness was significantly negatively correlated with lower cuticle thickness and pseudobulb vascular bundle diameter(P<0.05).Pseudobulb diameter was significantly positively correlated with epidermis thickness,pseudobulb vascular bundle number,and pseudobulb cross-sectional area,while pseudobulb vascular bundle diameter ratio was significantly negatively correlated with pseudobulb diameter,epidermis thickness,pseudobulb vascular bundle number,and pseudobulb cross-sectional area.Root indicators were significantly positively correlated,and root diameter,root sheath thickness,and cortex thickness were significantly negatively correlated with root vascular bundle diameter ratio.[Conclusion]Orchids possess a notably convergent adaptability,as evidenced by their stable root structure.Leaf and pseudobulb structures of orchids are mutually reinforcing and harmonizing,constituting the primary mechanism in respond to the arid Karst environment.
作者
吴天柔
安明态
王琨
余江洪
唐煜彬
WU Tianrou;AN Mingtai;WANG Kun;YU Jianghong;TANG Yubin(College of Forestry,Guizhou University,Guiyang 550025,China;Research Center for Biodiversity and Nature Conservation,Guizhou University,Guiyang 550025,China)
出处
《西北植物学报》
CAS
CSCD
北大核心
2024年第2期319-329,共11页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金项目(31960042)。
关键词
生态适应性
兰科植物
结构特征
喀斯特地区
ecological adaptability
Orchidaceae
structural characteristics
Karst region
作者简介
吴天柔(1998-),女,硕士研究生,主要从事植物多样性保护(植物方向)研究。E-mail:18885476181@163.com;通信作者:安明态,博士,正高级实验师,主要从事生物多样性保护、植物分类学和喀斯特森林生态学研究。E-mail:gdanmingtai@126.com。
