Glandular trichomes of Tussilago Farfara (Senecioneae, Asteraceae)

Abstract

The glandular trichomes are developed on the aerial organs of Tussilago farfara ; they produce phenols and terpenoids. Smooth endoplasmic reticulum and leucoplasts are the main organelles of the trichome secretory cells. The aim of this study was to characterise the morphology, anatomy, histochemistry and ultrastructure of the trichomes in Tussilago farfara as well as to identify composition of the secretory products. Structure of trichomes located on the peduncles, bracts, phyllaries, and leaves were studied by light and electron microscopy. The capitate glandular trichomes consist of a multicellular head and a biseriate long stalk. Histochemical tests and fluorescence microscopy reveal phenols and terpenoids in the head cells. During secretory stage, the head cells contain smooth and rough endoplasmic reticulum, Golgi apparatus, diversiform leucoplasts with opaque contents in lamellae, chloroplasts, mitochondria, and microbodies. In the capitate glandular trichomes of T. farfara subcuticular cavity is absent, unlike glandular trichomes in other Asteraceae species. For the first time, content of metabolites in the different vegetative and reproductive organs as well as in the isolated capitate glandular trichomes was identified by GC-MS. Forty-five compounds, including organic acids, sugars, polyols, phenolics, and terpenoids were identified. It appeared that metabolite content in the methanol extracts from peduncles, bracts and phyllaries is biochemically analogous, and similar to the metabolites from leaves, in which photosynthesis happens. At the same time, the metabolites from trichome extracts essentially differ and refer to the above-mentioned secondary substances. The study has shown that the practical value of the aerial organs of coltsfoot is provided with flavonoids produced in the capitate glandular trichomes.

Flower palate ultrastructure of the carnivorous plant Genlisea hispidula Stapf with remarks on the structure and function of the palate in the subgenus Genlisea (Lentibulariaceae)

“…Moreover, in the trichomes of these three species, TEM observations revealed that the cuticle became distended and separated from the cell walls of the head cells and formed a subcuticular space. A leucoplast that contained lamellae with osmiophilic inclusions was described from the secretory cell of the trichomes that produce phenols and terpenoids in Tussilago farfara and other Asteraceae species (Muravnik et al 2016, and literature therein). Muravnik et al (2016) suggested that the black deposition in the lamellae correspond to terpene precursors.…”

“…It is believed that microbodies actively participate in the production of secondary metabolites such as terpenoids and phenolic substances (e.g. Vassilyev 2000; Muravnik et al 2016). The lipid bodies in the cytoplasm and/or plastids with lipid globules were frequently recorded in osmophore tissues (e.g.…”

Localization and in-Vivo Characterization of Thapsia garganica CYP76AE2 Indicates a Role in Thapsigargin Biosynthesis

“…The presence of special storage structures in the root possibly containing terpenoids was investigated by a histochemical analysis using NADI (dimethyl-pphenyl-enediamine and a-naphthol) staining (David and Carde, 1964;Caissard et al, 2004;Jezler et al, 2013;Kromer et al, 2016;Muravnik et al, 2016;Steševi c et al, 2016;Stoji ci c et al, 2016). The NADI reagent has been reported to give rise to a blue/purple color in the presence of oxygenated or lipophilic compounds (e.g.…”

Replacing critical point drying with a low-cost chemical drying provides comparable surface image quality of glandular trichomes from leaves of Millingtonia hortensis L. f. in scanning electron micrograph

“…Apart from chemical drying, some researchers tend to use air drying method, which often resulted in producing tissue distortions (Zimmer 1989). In plants, glandular trichomes are considered as one of the most delicate surface structures (Muravnik et al 2016). In this study, we report our findings of SEM analysis on leaf glandular trichomes of Millingtonia hortensis, a tree species of Bignoniaceae widely distributed throughout south-east Asia, with an aim to reassess the CPD, HMDS and air-drying methods.…”