2024年7月19日 星期五
加拿大一枝黄花不同居群叶表皮和茎结构特征及其与环境因子的CCA分析
Structural features of leaf epidermis and stem of different populations of Solidago canadensis and CCA analysis of the structural features with environmental factors
2009年 第18卷 第3期 页码[1-10]    下载全文[1.7MB]  
摘要

对采自华东地区45个居群并移栽于同一生境条件下的加拿大一枝黄花(Solidago canadensis L.)叶表皮和茎横切面结构特征进行了比较观察,并对叶表皮和茎结构特征与环境因子、居群分布与环境因子的相关性进行了CCA分析。结果表明,加拿大一枝黄花叶片上、下表皮毛均为单列多细胞型非腺毛,下表皮毛密度高于上表皮;上表皮细胞为多边形且垂周壁平直或波状,下表皮细胞为不规则形或多边形且垂周壁较平直或呈波状、浅波状;叶片上表皮几无气孔分布,下表皮均有气孔分布,气孔器为无规则型,气孔多近圆形;不同居群间表皮毛密度、气孔密度、气孔长度和宽度有显著差异,在较干燥环境下的居群表皮毛密度较大、气孔较小,在较湿润生境下的居群表皮毛较少、气孔较大。茎横切面均由表皮、皮层和中柱组成;各居群表皮和皮层结构没有明显差异,维管束数目差异明显(8.05~13.39 mm-1);髓部面积百分比也有明显差异(25.7%~49.5%)。叶表皮和茎结构特征的可塑性指数存在居群间差异,其中气孔密度的平均可塑性指数最大(0.38),髓部面积百分比的平均可塑性指数最小(0.13)。CCA分析结果表明,茎和叶表皮结构特征与土壤湿润度和纬度的关系较大,气孔密度、长度和宽度与土壤湿润度呈正相关,维管束数目、表皮毛密度及髓部面积百分比与土壤湿润度和纬度呈负相关;各居群的分布与分布地的土壤湿润度和纬度的相关性较大。结果显示,加拿大一枝黄花居群间的形态特征适应性分化利于其入侵不同的生境,而采用无性繁殖方式可保持其个体形态特征上的变异,从而增加其入侵的成功率。

Abstract

The structural features of leaf epidermis and stem transaction of 45 populations of Solidago canadensis L. collected in East China and transplanted in the same habit at were comparatively observed. The correlation of population distribution, structural features of leaf epidermis and stem with environmental factors were studied by canonical correspondence analysis(CCA). The results show that trichomes on upper and lower epidermis are all uniseriate multicellular non-glandular trichomes , and the trichome density of lower epidermis is higher than that of upper epidermis. The cell shape of upper epidermis is polygonal and the anticlinal wall is straight or arched, while the cell shape of lower epidermis is usually irregular or polygonal and the anticlinal wall is slightly straight, arched or sinuolate. Stomata  barely distribute on upper epidermis and mostly distribute on lower epidermis. Stomatal apparatus is anomocytic type, and stomatal shape is mostly subcircular. The trichome density of epidermis, stomatal density, length and width are significantly different among populations. Populations distributing in dry habit at shave higher trichome density of epidermis and smaller stomata, while populations distributing in humid habit at shave lower trichome density of epidermis and bigger stomata. The stem transaction is composed of epidermis, cortex and central cylinder. The structures of epidermis and cortex in stem are not significantly different among different populations, and there are significant differences in the vascular bund lenumber (8. 05- 13. 39mm - 1)and percentage of pith area(25. 7%- 49. 5%).There are differences in the plasticity index of structural features of leaf epidermis and stem among different populations, in which the mean plasticity index of stomatal density is the highest (0.38), and that of percentage of pith area is the lowest (0.13). The results of CCA analysis show that the structural features of leaf epidermis and stem have a greater correlation with soil humidity and latitude, and there is a positive correlation between density, length, width of stoma and soil humidity. The vascular bundle number, density of epidermal trichome and percentage of pith area are negatively correlated with soil humidity and latitude, and the correlation of population distribution with soil humidity and latitude in location is great. The adaptive differentiation of S. canadensis in morphological features benefits its invasion in different habitats, and those variation of morphological features may be maintained by vegetative propagation to increase success rate of invasion.

关键词加拿大一枝黄花居群; 外来入侵植物; 叶表皮; ; 结构特征; 环境因子; CCA分析;
Key wordsSolidago Canadensis L. population; alien invasive plant; leaf epidermis; stem; structural feature; environmental factor; CCA analysis
作者曹 飞,廖 园,马 玲,强 胜
所在单位南京农业大学杂草研究室,江苏南京210095
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基金项目国家科学技术部公益性行业科研专项(200709017); 江苏省科技攻关项目(BE2005349);