Laboratório de Anatomia Vegetal, Instituto Federal de Educação, Ciência e Tecnologia Goiano (IF Goiano, Campus Rio Verde), Rodovia Sul Goiana, Km 01, Zona Rural, Rio Verde, Goiás, 75901-970, Brazil.
Departamento de Biologia, Centro de Ciências, Universidade Federal Do Ceará, Campus Do Pici, Bloco 906, Av. Mister Hull S/N, 60.440-900, Fortaleza, Brazil.
Protoplasma. 2024 Mar;261(2):245-256. doi: 10.1007/s00709-023-01892-0. Epub 2023 Sep 12.
Secretory trichomes and colleters are two of the secretory structures whose exudates may cover the body of the plant. Such secretions comprise resins or mucilages which are associated with an array of ecological roles. In Rosaceae, secretory trichomes have been reported for the leaves while colleters associated with leaf teeth. Our study aimed to identify the secretory structures of Rosa lucieae and understand the ecological role played by these glands as interpreted by morphoanatomical and histochemical studies. Samples from developing and fully mature leaves were collected, fixed, and processed according to usual techniques for light and scanning electron microscopy. In R. lucieae, colleters are restricted to the leaf and stipular margins and are associated with the teeth. They present a parenchymatous axis surrounded by a secretory palisade epidermis and usually fall off after the secretory activity is finished. Different from colleters, secretory trichomes are persistent. They present a multicellular secretory head and stalk. They are found at the base of the leaflet, petiolule, rachis, and petiole and occasionally on the stipular and leaf margins. The colleters predominantly secrete mucilages while the secretory trichomes secrete lipids and terpenes, both via cuticle rupture. The secretory activity of colleters is predominant in the leaf primordia, holding leaflets together and protecting meristems and leaves from desiccation, while the secretory trichomes maintain their secretory activity at different stages of leaf development, protecting different regions of the leaf against pathogens and herbivores.
分泌毛和分泌腺是两种分泌结构，其分泌物可能覆盖植物的体表。这些分泌物包括树脂或黏液，与一系列生态角色有关。在蔷薇科中，已经报道了叶片上的分泌毛，而与叶片齿有关的则是分泌腺。我们的研究旨在鉴定玫瑰 lucieae 的分泌结构，并通过形态解剖学和组织化学研究来理解这些腺体所扮演的生态角色。采集发育中和完全成熟叶片的样本，按照常规的光镜和扫描电镜技术进行固定和处理。在 R. lucieae 中，分泌腺仅限于叶片和托叶边缘，并与齿有关。它们呈现出一个由分泌栅栏表皮包围的薄壁组织轴，通常在分泌活动结束后脱落。与分泌腺不同，分泌毛是持久的。它们呈现出一个多细胞的分泌头和柄。它们位于小叶、叶柄、中脉和叶柄的基部，偶尔也在托叶和叶片边缘发现。分泌腺主要分泌黏液，而分泌毛则分泌脂质和萜烯，都是通过角质层破裂来实现的。分泌腺的分泌活动主要发生在叶片原基中，将小叶固定在一起，并保护分生组织和叶片免受干燥，而分泌毛则在叶片发育的不同阶段保持其分泌活动，保护叶片的不同区域免受病原体和食草动物的侵害。
