CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Microsc Res Tech. 2021 Mar;84(3):521-530. doi: 10.1002/jemt.23608. Epub 2020 Sep 29.
The family Scrophulariaceae consists of taxonomically complex genera and species. The delimitation of the taxa within this family is always challenging. In this paper, we studied leaf epidermis anatomical characteristics and its taxonomic significance of four species belonging to four genera of the family Scrophulariaceae collected from northern Pakistan. The species were examined under light and scanning electron microscopes (LM and SEM). Qualitative and quantitative foliar epidermal anatomical features were examined for both adaxial and abaxial surfaces. Qualitative characters like epidermal cell shape, epidermal cell cover, anticlinal wall, trichomes type, stomata type and stomata position were examined. Quantitative characters like the length and width of leaf epidermis, stomata, stomatal pore, subsidiary cell and trichomes for both adaxial and abaxial surfaces were studied and measured. Stomatal index within the species and between the species was found to be different on adaxial and abaxial surfaces. Diacytic stomata and glandular trichomes on epidermis were only found in Anticharis glandulosa while rest of the taxa has anomocytic type stomata and dendroid trichomes on both surfaces. Based on the micromorphological characters, we did principal component analysis (PCA), and cluster analysis for the species delimitation and identification. A taxonomic key has been provided to delimit and identify the studied taxa based on foliar epidermal characters. The aim of the present research was to elucidate the micromorphological characters to distinguish the studied taxa for taxonomic purposes.
玄参科植物由分类上复杂的属和种组成。该科内各分类单元的界定一直具有挑战性。本文研究了来自巴基斯坦北部的玄参科四个属的四个种的叶片表皮解剖特征及其分类学意义。使用光学显微镜（LM）和扫描电子显微镜（SEM）对这些种进行了观察。对叶片的上下表皮分别进行了定性和定量的表皮解剖特征分析。定性特征如表皮细胞形状、表皮细胞覆盖物、垂周壁、毛状体类型、气孔类型和气孔位置等进行了检查。对上下表皮的叶片表皮、气孔、气孔孔径、副卫细胞和毛状体的长度和宽度等定量特征进行了研究和测量。发现同一物种的叶片上下表皮和不同物种之间的气孔指数都存在差异。表皮上的二细胞型气孔和腺毛仅存在于 Anticharis glandulosa 中，而其他分类单元的上下表皮都具有不等细胞型的气孔和树枝状毛状体。基于微观形态特征，我们进行了主成分分析（PCA）和聚类分析，以对物种进行界定和鉴定。根据叶片表皮特征，我们提供了一个分类学的关键，以对研究的分类单元进行界定和识别。本研究的目的是阐明微观形态特征，以便为分类目的区分研究的分类单元。
