Ghimire Balkrishna, Park Beom Kyun, Son Dong Chan
Faculty of Forestry, Agriculture and Forestry University, Hetauda, Nepal.
Division of Forest Biodiversity, Korean National Arboretum, Pocheon, Republic of Korea.
PeerJ. 2024 Sep 10;12:e17997. doi: 10.7717/peerj.17997. eCollection 2024.
, one of the largest genera of the family Ranunculaceae, has a wide array of morphological variation and is considered the most difficult group of taxa in terms of infrageneric discrimination. This study assessed the leaf micromorphological features of 19 taxa (16 species and three varieties) found in Korea. The leaf surface features were studied under scanning electron microscopy, and the stomatal counting and measurement were carried out under light microscopy. are hypostomatic, meaning the stomata are only found on the abaxial surface of the leaf. Observed taxa showed near uniformity in the epidermal cell type, structure, and morphology on both surfaces of the leaf. Differences were observed in the presence and absence and/or abundance of trichomes on both the adaxial and abaxial surfaces, the epidermal cell boundary, and the periclinal and anticlinal wall of the cells. Differences were also observed in the number of the epidermal cells connected with the stomata on the abaxial surface, with small differences noted in epidermal cell shapes. The ANOVA showed a significant variation in the stomata density in the studied taxa ( < 0.0001). The cluster analysis based on 13 leaf micromorphological features generated four major clusters. These results indicated similarities in certain key leaf micromorphological features among taxa from the , , and sections. In the genus , as with other morphological characteristics, using leaf micromorphological characters alone, which possess limited taxonomic value, proves inadequate for resolving infrageneric relationships. However, incorporating certain features with other morphological characteristics offers a possible alternative means of determining the infrageneric relationships within the genus.
毛茛科最大的属之一，具有广泛的形态变异，被认为是属下分类中最困难的类群。本研究评估了在韩国发现的19个分类单元（16个种和3个变种）的叶片微观形态特征。在扫描电子显微镜下研究叶片表面特征，并在光学显微镜下进行气孔计数和测量。气孔下生，即气孔仅存在于叶片的下表面。观察到的分类单元在叶片两面的表皮细胞类型、结构和形态上表现出近乎一致。在叶片的上表面和下表面，观察到毛状体的有无和/或丰度、表皮细胞边界以及细胞的平周壁和垂周壁存在差异。在下表面与气孔相连的表皮细胞数量也存在差异，表皮细胞形状有细微差异。方差分析表明，在所研究的分类单元中气孔密度存在显著差异（<0.0001）。基于13个叶片微观形态特征的聚类分析产生了四个主要类群。这些结果表明，来自[具体类群1]、[具体类群2]和[具体类群3]组的分类单元在某些关键叶片微观形态特征上具有相似性。在该属中，与其他形态特征一样，仅使用叶片微观形态特征，其分类价值有限，不足以解决属下关系。然而，将某些特征与其他形态特征相结合，为确定该属内的属下关系提供了一种可能的替代方法。
