Gorges Helen, Serbe Elena, Kovalev Alexander, Gorb Stanislav N
Department of Functional Morphology and Biomechanics, Zoological Institute, Kiel University, Am Botanischen Garten 1-9, 24118 Kiel, Germany.
J Exp Bot. 2025 Jan 14. doi: 10.1093/jxb/eraf014.
Several plant seeds release a mucilaginous envelope through hydration, rich in pectins and stabilized by cellulose fibers. This mucilage aids in seed protection, development, and adhesion for dispersal. This study aimed to separate the effects of pectins and cellulose fibers by using pectinase to remove mucilage pectins, leaving cellulose arrays, and performing wet and dry pull-off force measurements on seeds of three plant species: Salvia hispanica (Chia), Collomia grandiflora (Collomia) and Linum usitatissimum (Flax). We used light and scanning electron microscopy to confirm partial pectin removal and intact cellulose fibers. Pull-off force measurements revealed similar wet adhesive properties and E-moduli in S. hispanica and C. grandiflora seeds before and after pectin removal. L. usitatissimum seeds, lacking cellulose fibers, exhibited significantly lower wet and dry adhesion forces post-pectin removal. Desiccation dynamics showed shorter desiccation times after pectin removal in all three species. Results indicated that adhesion forces in seed mucilage with cellulose fibers did not change significantly after pectin removal, suggesting that cellulose fibers contribute to the adhesive properties of seed mucilage, while pectins might not play an exclusive role in adhering to surfaces.
几种植物种子通过水合作用释放出富含果胶并由纤维素纤维稳定的黏液包膜。这种黏液有助于种子保护、发育以及用于传播的附着。本研究旨在通过使用果胶酶去除黏液中的果胶，留下纤维素阵列，并对三种植物种子进行湿态和干态剥离力测量，以分离果胶和纤维素纤维的作用，这三种植物分别是西班牙鼠尾草（奇亚籽）、大花山字草和亚麻。我们使用光学显微镜和扫描电子显微镜来确认果胶的部分去除和纤维素纤维的完整性。剥离力测量结果显示，去除果胶前后，西班牙鼠尾草和大花山字草种子的湿黏附特性和弹性模量相似。缺乏纤维素纤维的亚麻种子在去除果胶后，其湿态和干态黏附力显著降低。干燥动力学表明，所有三个物种在去除果胶后干燥时间缩短。结果表明，去除果胶后，含有纤维素纤维的种子黏液的黏附力没有显著变化，这表明纤维素纤维有助于种子黏液的黏附特性，而果胶可能在黏附于表面方面并非起唯一作用。
