Kaur Satinderpal, Khanal Neetu, Dearth Robert, Kariyat Rupesh
Department of Biology, University of Texas Rio Grande Valley, Edinburg, TX, 78539, USA.
Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, AR, USA.
Bot Stud. 2023 Mar 29;64(1):7. doi: 10.1186/s40529-023-00370-3.
Trichomes, the hairlike protuberances in plants, have been well known to act as the first line of defense against herbivores, and abiotic stresses, along with other structural defenses such as spines, thorns, and waxes. We previously reported the tremendous variation in trichome traits among different wild and cultivated Solanum species and demonstrated that trichomes types and density are traditionally miscalculated and often misnamed. However, intraspecific variation in trichome traits is poorly understood, although this has implications for stress tolerance and resistance breeding programs in economically important crop species and can also mediate ecological interactions at multiple trophic levels in their wild congeners. In this study, using tomato as a model, we characterized the trichomes from 10 commonly grown varieties using a minimal sample prep desktop scanning electron microscopy, and followed up with estimating their dimensions across the varieties and trichome types. We hypothesized that although trichome number may vary, the varieties will have similar trichome types, based on current literature. Our results show that there is significant variation for trichome number as well as dimensions of trichome types among these varieties. Furthermore, when we separately analyzed the number and dimensions of commonly found glandular and non-glandular trichomes, the results were consistent with broad assessment of trichomes, showing consistent variation among varieties, suggesting that trichome studies should not be limited to basic classification into glandular and non-glandular, and should accommodate the sub-types and their dimensions.
植物体表的毛状体是一种毛发状的突出物，众所周知，它与其他结构防御（如刺、棘和蜡质）一起，构成了抵御食草动物和非生物胁迫的第一道防线。我们之前报道了不同野生和栽培茄属物种之间毛状体特征的巨大差异，并证明了毛状体类型和密度在传统上被错误计算且常常被错误命名。然而，尽管毛状体特征的种内变异对经济上重要的作物物种的胁迫耐受性和抗性育种计划有影响，并且还能在其野生同属植物的多个营养级介导生态相互作用，但我们对其了解甚少。在本研究中，我们以番茄为模型，使用最少样品制备的台式扫描电子显微镜对10个常见栽培品种的毛状体进行了表征，并进一步估计了不同品种和毛状体类型的毛状体尺寸。基于现有文献，我们假设尽管毛状体数量可能不同，但这些品种将具有相似的毛状体类型。我们的结果表明，这些品种之间的毛状体数量以及毛状体类型的尺寸存在显著差异。此外，当我们分别分析常见的腺毛和非腺毛的数量和尺寸时，结果与对毛状体的广泛评估一致，表明品种间存在一致的差异，这表明毛状体研究不应局限于基本的腺毛和非腺毛分类，还应考虑亚类型及其尺寸。
