scholarly journals Structure and distribution of glandular and non-glandular trichomes on above-ground organs in Inula helenium L. (Asteraceae)

2014 ◽  
Vol 66 (4) ◽  
pp. 25-34 ◽  
Author(s):  
Aneta Sulborska

Micromorphology and distribution of glandular and non-glandular trichomes on the above-ground organs of <em>Inula helenium </em>L. were investigated using light and scanning electron microscopy (SEM). Two types of biseriate glandular trichomes, i.e. sessile and stalk hairs, and non-glandular trichomes were recorded. Sessile glandular trichomes were found on all examined <em>I. helenium </em>organs (with their highest density on the abaxial surface of leaves and disk florets, and on stems), whereas stalk glandular trichomes were found on leaves and stems. Sessile trichomes were characterised by a slightly lower height (58–103 μm) and width (32–35 μm) than the stalk trichomes (62–111 μm x 31–36 μm). Glandular hairs were composed of 5–7 (sessile trichomes) or 6–9 (stalk trichomes) cell tiers. Apical trichome cell tiers exhibited features of secretory cells. Secretion was accumulated in subcuticular space, which expanded and ruptured at the top, and released its content. Histochemical assays showed the presence of lipids and polyphenols, whereas no starch was detected. Non-glandular trichomes were seen on involucral bracts, leaves and stems (more frequently on involucral bracts). Their structure comprised 2–9 cells; basal cells (1–6) were smaller and linearly arranged, while apical cells had a prozenchymatous shape. The apical cell was the longest and sharply pointed. Applied histochemical tests revealed orange-red (presence of lipids) and brow colour (presence of polyphenols) in the apical cells of the trichomes. This may suggest that beside their protective role, the trichomes may participate in secretion of secondary metabolites.

2016 ◽  
Vol 68 (2) ◽  
pp. 291-301 ◽  
Author(s):  
Dusica Janosevic ◽  
Snezana Budimir ◽  
Ana Alimpic ◽  
Petar Marin ◽  
Sheef Al ◽  
...  

We performed a comprehensive study of trichomes considering the medicinal importance of the essential oils produced in glandular trichomes of Salvia aegyptiaca L. and lack of data about leaf trichome characteristics. Micromorphological and histochemical analyses of the trichomes of S. aegyptiaca were carried out using light and scanning electron microscopy. We report that the leaves contained abundant non-glandular unbranched trichomes and two types of glandular trichomes, peltate and capitate, on both leaf surfaces. The abaxial leaf side was covered with numerous peltate and capitate trichomes, while capitate trichomes were more abundant on the adaxial leaf side, where peltate trichomes were rarely observed. The non-glandular trichomes were unicellular papillae and multicellular, uniseriate, two-to-six-celled, erect or slightly leaning toward the epidermis. Peltate trichomes were composed of a basal cell, a short cylindrical stalk cell and a broad head of eight secretory cells arranged in a single circle. Capitate trichomes consisted of a one-celled glandular head, subtended by a stalk of variable length, and classified into two types: capitate trichomes type I (or short-stalked glandular trichomes) and capitate trichomes type II (or long-stalked glandular trichomes). Histochemical tests showed that the secreted material in all types of S. aegyptiaca glandular trichomes was of a complex nature. Positive reactions to lipids for both types of glandular trichomes were obtained, with especially abundant secretion observed in peltate and capitate trichomes type II.


2015 ◽  
Vol 63 (2) ◽  
pp. 537 ◽  
Author(s):  
Thália Do Socorro Serra Gama ◽  
Diego Demarco ◽  
Ana Cristina Andrade de Aguiar-Dias

<p class="Normal1">Plant structures that secrete lipids and phenolic compounds are often associated with the protection and development of organs against desiccation, in addition to the protection they provide against animals, as the capitate trichomes of <em>Adenocalymma magnificum</em>. Understanding the glandular activities that occur in these trichomes has required the study of their ontogeny, structure, ultrastructure and histochemical aspects; the interpretation of their ecological functions or evolutionary history is complicated by the scarcity of reports on calicinal trichomes that are not nectar-secreting. Samples of floral calyx in anthesis and flower buds at different stages of development were fixed and processed according to the methods for light and electron microscopy. The trichomes are randomly distributed throughout the entire inner surface of the calyx and are also visible on the flower buds. These capitate glandular trichomes were composed of a peduncle, having up to nine cells, and a multicellular secretory head with their cells in columnar format and arranged in disc form. The collar cell, which is under the secretory head, divides anticlinally and arranges itself side by side with the mother cell. As they develop, they bend with some of them becoming adpressed to the calyx. Histochemical tests indicate that the secretory head cells produce lipid substances, acidic lipids and phenolic compounds. In the secretory head, the vacuome is dispersed and the cytoplasm possesses a great number of smooth endoplasmic reticulum and leucoplasts, organelles involved in the production of osmiophilic substances. In some regions of the secretory cells, cuticle detachment was observed; however, the accumulation of secretions was not observed. This study describes, for the first time, the origin, development, and secretion process of the calicinal trichomes of <em>Adenocalymma magnificum</em>, showing that production of lipophilic substances is important for this plant, possibly the trichomes may be involved in the plant’s chemical defense against insects, offering protection against herbivores.</p>


Planta ◽  
2020 ◽  
Vol 252 (6) ◽  
Author(s):  
Agata Konarska ◽  
Barbara Łotocka

Abstract Main Conclusion Permanent glandular trichomes of Robinia viscosa var. hartwigii produce viscous secretion containing several secondary metabolites, as lipids, mucilage, flavonoids, proteins and alkaloids. Abstract Robinia viscosa var. hartwigii (Hartweg’s locust) is an ornamental tree with high apicultural value. It can be planted in urban greenery and in degraded areas. The shoots, leaves, and inflorescences of this plant are equipped with numerous persistent glandular trichomes producing sticky secretion. The distribution, origin, development, morphology, anatomy, and ultrastructure of glandular trichomes of Hartweg's locust flowers as well as the localisation and composition of their secretory products were investigated for the first time. To this end, light, scanning, and transmission electron microscopy combined with histochemical and fluorescence techniques were used. The massive glandular trichomes differing in the distribution, length, and stage of development were built of a multicellular and multiseriate stalk and a multicellular head. The secretory cells in the stalk and head had large nuclei with nucleoli, numerous chloroplasts with thylakoids and starch grains, mitochondria, endoplasmic reticulum profiles, Golgi apparatus, vesicles, and multivesicular bodies. Many vacuoles contained phenolic compounds dissolved or forming various condensed deposits. The secretion components were transported through symplast elements, and the granulocrine and eccrine modes of nectar secretion were observed. The secretion was accumulated in the subcuticular space at the trichome apex and released through a pore in the cuticle. Histochemical and fluorescence assays showed that the trichomes and secretion contained lipophilic and polyphenol compounds, polysaccharides, proteins, and alkaloids. We suggest that these metabolites may serve an important function in protection of plants against biotic stress conditions and may also be a source of phytopharmaceuticals in the future.


1979 ◽  
Vol 57 (7) ◽  
pp. 714-729 ◽  
Author(s):  
Janet Vermeer ◽  
R. L. Peterson

Glandular trichomes on the inflorescence of Chrysanthemum morifolium cv. Dramatic are initiated from a single epidermal cell outgrowth and develop through an anticlinal division and a series of periclinal divisions to form a biseriate multicellular structure. Cells of the young trichome contain a large nucleus with prominent nucleoli and few small cellular organelles. Prior to the secretory stage, numerous ribosomes, polyribosomes, and dictyosomes are present in a dense cytoplasm but most of the dictyosomes are lost as secretion commences. Plastids in the stalk cells senesce but in a different manner than those in the upper tiers of secretory cells. Lipoidal substances form in the degenerating plastids. Cell wall ingrowths and the deposition of a flocculent material in the primary cell wall characterize secretory hairs. In very old hairs cellular lysis takes place with mitochondria being the last cellular organelle to remain intact. The secreted material, which collects in a subcuticular space, appears to be a terpenoid. The function of this material is not known.


1967 ◽  
Vol 22 (9) ◽  
pp. 972-976 ◽  
Author(s):  
Rainer Bergfeld

The young gametophytes of the fern Dryopteris filix-mas (L.) SCHOTT have different metabolic patterns in red and blue light with blue favouring protein formation. In connection with this, the morphogenesis is also different. Two-dimensional prothallia are developed in blue light; in red light, however, the gametophytes grow as filaments. In the present paper the influence of red and blue radiation upon the size of the nuclei and nucleoli has been studied in fully differentiated stable basal cells and actively dividing apical cells. Time course studies revealed that the apical cell of the red form always contains extremly large nuclei and nucleoli. This is in agreement with high synthetic activity of this cell. In contrast, the apical cells with two cutting faces of the blue grown gametophytes have much smaller nuclei and nucleoli (this may be due to the comparativly high dividing activity of this cells). In already differentiated basal cells, these two organelles are even smaller and show only minor differences between red and blue ones. Within the gametophytes there is a gradient in the nucleus and nucleolus size from the apical to the basal cells.If blue grown gametophytes are brought into red light, or vice versa, typical changes in size of the nucleus and nucleolus in the direction of the respective forms are already visible after 3 hrs. under the new conditions. These changes in size and synthetic activity occur much earlier than any measurable morphological alteration. The data give good evidence for the fact that the striking change in the morphogenesis is preceded by a fundamental change in the synthetic activity of the nucleus and nucleolus.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4166
Author(s):  
Agata Konarska ◽  
Elżbieta Weryszko-Chmielewska ◽  
Anna Matysik-Woźniak ◽  
Aneta Sulborska ◽  
Beata Polak ◽  
...  

The aim of this study was to conduct a histochemical analysis to localize lipids, terpenes, essential oil, and iridoids in the trichomes of the L. album subsp. album corolla. Morphometric examinations of individual trichome types were performed. Light and scanning electron microscopy techniques were used to show the micromorphology and localization of lipophilic compounds and iridoids in secretory trichomes with the use of histochemical tests. Additionally, the content of essential oil and its components were determined using gas chromatography-mass spectrometry (GC-MS). Qualitative analyses of triterpenes carried out using high-performance thin-layer chromatography (HPTLC) coupled with densitometric detection, and the iridoid content expressed as aucubin was examined with spectrophotometric techniques. We showed the presence of iridoids and different lipophilic compounds in papillae and glandular and non-glandular trichomes. On average, the flowers of L. album subsp. album yielded 0.04 mL/kg of essential oil, which was dominated by aldehydes, sesquiterpenes, and alkanes. The extract of the L. album subsp. album corolla contained 1.5 × 10−3 ± 4.3 × 10−4 mg/mL of iridoid aucubin and three triterpenes: oleanolic acid, β-amyrin, and β-amyrin acetate. Aucubin and β-amyrin acetate were detected for the first time. We suggest the use of L. album subsp. album flowers as supplements in human nutrition.


2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Ping Jia ◽  
Ting Gao ◽  
Hua Xin

The types, morphology, distribution, structure, and development process of the glandular trichomes on the leaves ofThymus quinquecostatusCelak had been investigated in this study. Two different types of glandular trichomes were determined in detail, namely, capitate trichomes and peltate ones. Besides, there were distinct differences on morphology, distribution, structure, and development process between the two kinds of trichomes. As the peltate trichome stepping into senium stage, it caved in the epidermis integrally, which was different from the capitate one. The secretion of the capitate trichome contained essential oil, polyphenols, and flavonoids, while, in addition to these three components, the secretion of the peltate one also contained acid polysaccharides. A distinctive difference was also seen in the secretory pathway of the secretion between the two types of trichomes. The secretion of capitate one was extruded through the cuticle of the head cell, but the secretion of the peltate one kept accumulating in the subcuticular space of the head cells until it was released by cuticle rupture.


2013 ◽  
Vol 65 (1) ◽  
pp. 239-246 ◽  
Author(s):  
Sheef Al ◽  
Sonja Duletic-Lausevic ◽  
Dusica Janosevic ◽  
Snezana Budimir ◽  
Marija Marin ◽  
...  

Micromorphological and ultrastructural analyses of the leaf trichomes of Salvia fruticosa Mill. were performed by light and electron microscopy. The leaves bear numerous non-glandular unbranched trichomes, and peltate, capitate and digitiform glandular trichomes. Very elongated flagelliform non-glandular trichomes densely covered the leaf surfaces, with especially abundance on the leaf margins. Peltate trichomes consist of a basal epidermal cell, a very short stalk cell and a large round head of eight secretory cells arranged in a circle. Capitate trichomes can be divided into two main types, short-stalked and long-stalked, and further into five subtypes according to the number of stalk cells, morphology and number of glandular head cells. Digitiform trichomes consist of one basal cell, one or two stalk cells and one apical secretory cell, which are of similar diameter and approximately equal length.


2012 ◽  
Vol 24 (1) ◽  
pp. 287
Author(s):  
Anna Lange Consiglio ◽  
Enrica Zucca ◽  
Fausto Cremonesi ◽  
Sheila Laverty ◽  
Jean Pierre Lavoie ◽  
...  

The airway epithelium is subjected to a lifetime exposure to inhaled particles and pathogens that may lead to the development of a variety of infectious and inflammatory respiratory diseases such as chronic bronchitis, asthma and chronic obstructive pulmonary disease. These disorders are typically associated with changes in the architecture of the airway walls,that range from epithelial structure remodeling to complete denudation of the basement membrane. The repair of injuries and the regeneration of the epithelial structure involve stem and progenitor cells. Although both secretory and basal cells are able to proliferate, only basal cells are recently suggested to represent the stem cell (SC) niche of the airway epithelium in human tracheas and bronchi, but the adult secretory cells lose their regeneration potential compared to the fetal secretory cells. For this reason, researchers are considering other sources for exogenous pluripotent SCs for airway tissue engineering. At present, autologous bone marrow and adipose derived MSCs seem to present the most popular SC type used in laryngotracheal tissue engineering. Extra-fetal derived SCs could represent new alternative cell sources for lung regeneration. Investigations of stem cell therapy for murine lung injuries revealed an excellent regeneration potential of extra-fetal derived cells that integrated into the lung and differentiated into pulmonary lineages after injury. Recurrent airway obstruction disease (RAO) in the horse is one of the only naturally occurring diseases in animals that is comparable to bronchial asthma in humans. The anamnestic and reversible nature of equine RAO is similar to some forms of human asthma suggesting a common immunological basis. Based on similarities between human asthma and equine RAO, we propose to use spontaneously RAO affected horses as an animal model in biomedical research. We describe the isolation, in vitro proliferation capacity and labeling of equine extra-fetal derived cells, and preliminary in vivo results indicating that after local injection, labeled cells could be retrieved by bronchoalveolar lavage from selected pulmonary areas.


2019 ◽  
Vol 25 (6) ◽  
pp. 1482-1490 ◽  
Author(s):  
Jamile Fernanda Silva Cossolin ◽  
Luis Carlos Martínez ◽  
Monica Josene Barbosa Pereira ◽  
Lucia Madalena Vivan ◽  
Hakan Bozdoğan ◽  
...  

AbstractThe burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described. The salivary system has a pair of principal salivary glands and a pair of accessory salivary glands. The principal salivary gland is bilobed with anterior and posterior lobes joined by a hilus where an excretory duct occurs. The accessory salivary gland is tubular with a narrow lumen that opens into the hilus near the excretory duct, suggesting that its secretion is stored in the lumen of the principal gland. The cytoplasm of the secretory cells is rich in the rough endoplasmic reticulum, secretory vesicles with different electron densities and mitochondria. At the base of the accessory gland epithelium, there were scattered cells that do not reach the gland lumen, with the cytoplasm rich in the rough endoplasmic reticulum, indicating a role in protein production. Data show that principal and accessory salivary glands of S. castanea produce proteinaceous saliva. This is the first morphological description of the S. castanea salivary system that is similar to other Hemiptera Pentatomomorpha, but with occurrence of basal cells in the accessory salivary gland.


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