Bhat Mudassir A, Shakoor Sheikh A, Badgal Priya, Soodan Amarjit S
Plant Systematics and Biodiversity Laboratory, Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar, India.
Front Plant Sci. 2018 Jun 22;9:864. doi: 10.3389/fpls.2018.00864. eCollection 2018.
The role and significance of phytoliths in taxonomic diagnosis of grass species has been well documented with a focus on the types found in foliar epidermis and the synflorescence. The present paper is an attempt to broaden the scope of phytoliths in species diagnosis of grasses by developing phytolith signatures of some species of the foxtail genus P. Beauv. through location and physico-chemical analysis of various phytolith morphotypes in different parts of the plant body. Clearing solution and dry ashing extraction methods were employed for location and isolation of phytolith morphotypes respectively. Ultrastructural details were worked out by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy. Morphometric and frequency data of phytolith morphotypes were also recorded. Biochemical architecture of various phytolith types was worked out through SEM-EDX, XRD, and FTIR analysis. Data were analyzed through Principal Component Analysis and Cluster Analysis. location of phytoliths revealed species specific epidermal patterns. The presence of cystoliths (calcium oxalate crystals) in the costal regions of adaxial leaf surface of (L.) P. Beauv. is the first report for the genus . Our results revealed marked variations in epidermal ornamentation and undulation patterns with a novel "Λ" (Lamda) type of undulated ornamentation reported in . Dry ashing method revealed species specific clusters of phytolith morphotypes. The study revealed that phytoliths can play a significant role in resolution of taxonomic identity of three species of . Each species was marked out by a unique assemblage of phytolith morphotypes from various parts of the plant body. Apart from location and epidermal patterning, diagnostic shapes, frequency distribution, size dimensions, and biochemical architecture emerged as complementary traits that help in developing robust phytolith signatures for plant species.
植硅体在禾本科物种分类诊断中的作用和意义已有充分记载，重点关注叶表皮和花序中发现的类型。本文试图通过对狐尾草属一些物种的植硅体特征进行研究，扩大植硅体在禾本科物种诊断中的应用范围，具体方法是对植物不同部位的各种植硅体形态类型进行定位和理化分析。分别采用清除液法和干灰化提取法对植硅体形态类型进行定位和分离。通过扫描电子显微镜（SEM）和透射电子显微镜确定超微结构细节。还记录了植硅体形态类型的形态测量和频率数据。通过SEM-EDX、XRD和FTIR分析确定各种植硅体类型的生化结构。通过主成分分析和聚类分析对数据进行分析。植硅体的定位揭示了物种特异性的表皮模式。在狐尾草叶正面叶脉区域存在钟乳体（草酸钙晶体），这是该属的首次报道。我们的结果显示表皮纹饰和起伏模式存在显著差异，其中报道了一种新颖的“Λ”（拉姆达）型起伏纹饰。干灰化法揭示了物种特异性的植硅体形态类型聚类。研究表明，植硅体在解决三种狐尾草的分类身份问题上可以发挥重要作用。每个物种都由植物不同部位独特的植硅体形态类型组合所标记。除了定位和表皮模式外，诊断形状、频率分布、尺寸大小和生化结构也成为互补特征，有助于为植物物种开发强大的植硅体特征。
