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Scorzoneroides autumnalis is a highly polymorphic perennial with several described infraspecific taxa, largely differing in involucre colour and indumentum intensity. Here, we examine the role of ecotypic divergence and phenotypic plasticity in shaping large‐scale geographical variation in these characters. We collected phenotypic data from herbarium specimens and garden‐grown plants of S. autumnalis, representing several habitats throughout Scandinavia and Iceland, and subjected progenies from controlled crosses within a subset of the common garden material to different temperature regimes to assess patterns of phenotypic plasticity. Our results strongly suggest that colour and indumentum of involucral bracts, as well as the size of capitula (measured by ligule length), are environmentally plastic and much affected by temperature. Reduced temperature resulted in significantly larger capitula, with both thicker and darker involucre indumentum. Since dark colouration, dense indumentum and large floral structures have been shown to facilitate heat retention and insect visitation in other plant species growing in cold climate, we hypothesize that plants of S. autumnalis benefit from possessing these features under cool conditions, and that much of the geographical variation in capitulum characters reflects adaptive phenotypic plasticity rather than ecotypic divergence. For this reason, we deem these characters to have a low taxonomic value for distinguishing infraspecific taxa within S. autumnalis. [ABSTRACT FROM AUTHOR]

The morphological diversity of trichomes and pappi in 20 common Asteraceae members were studied from the standpoint of species identification. Thirteen of these species bear trichomes on all surfaces and 16 types of trichomes were recorded. Non-glandular, multicellular, uniseriate trichomes with long terminal cell are the most common type recorded at 87 observed surfaces of 16 species. Some trichome types were restricted to one or two species. The trichomes of Leucomeris spectabilis are being reported for the first time. The pappi were recorded in 13 species and their morphology is quite characteristic of species and genera. Separate dichotomous keys are constructed to help identify the species on the basis of trichomes and pappi exclusively. [ABSTRACT FROM AUTHOR]

Premise: Cultivation and naturalization of plants beyond their natural range can bring previously geographically isolated taxa together, increasing the opportunity for hybridization, the outcomes of which are not predictable. Here, we explored the phenotypic and genomic effects of interspecific gene flow following the widespread cultivation of Mentha spicata (spearmint), M. longifolia, and M. suaveolens. Methods: We morphologically evaluated 155 herbarium specimens of three Mentha species and sequenced the genomes of a subset of 93 specimens. We analyzed the whole genomes in a population and the phylogenetic framework and associated genomic classifications in conjunction with the morphological assessments. Results: The allopolyploid M. spicata, which likely evolved in cultivation, had altered trichome characters, that is possibly a product of human selection for a more palatable plant or a byproduct of selection for essential oils. There were signs of genetic admixture between mints, including allopolyploids, indicating that the reproductive barriers between Mentha species with differences in ploidy are likely incomplete. Still, despite gene flow between species, we found that genetic variants associated with the cultivated trichome morphology continue to segregate. Conclusions: Although hybridization, allopolyploidization, and human selection during cultivation can increase species richness (e.g., by forming hybrid taxa), we showed that unless reproductive barriers are strong, these processes can also result in mixing of genes between species and the potential loss of natural biodiversity. [ABSTRACT FROM AUTHOR]

Cephalaria pastricensis subsp. pologensis Teofilovski (Dipsacaceae), from NW North Macedonia, is reported as a new subspecies to science. It is distinguished from C. pastricensis Dörfl. & Hayek subsp. pastricensis by its densely, ± patent-subvillous petioles and rachis of the leaves, and the midrib of the lower surface of the leaf lobes (vs. with sparse, short, ± appressed hairs), densely pubescent lower surface of the leaves (vs. with scattered hairs on the nerves), and densely pubescent to subglabrous upper surface of the leaves (vs. glabrous or with scattered hairs on the nerves). The new subspecies is a Macedonian endemic known from small areas in the Šar Mountains (near Brezno village) and Mt. Buković (near Gorna Đonovica village). Its distribution range is geographically distinct from that of C. pastricensis subsp. pastricensis, which is a Balkan endemic, distributed in Albania, Montenegro, Bosnia and Herzegovina, Kosovo, and Serbia. [ABSTRACT FROM AUTHOR]

The article provides information on the occurrence of Tilia ×haynaldiana, a hybrid of T. platyphyllos and T. tomentosa, in Greece. This hybrid has been previously known to exist only in Northwest Romania and Montenegro. T. ×haynaldiana combines two characteristic features of its parental species: the ribbed fruits of T. platyphyllos and the stellate indumentum of T. tomentosa. Probably, such hybrids are more common than reported earlier but often are not distinguished from their parental species. [ABSTRACT FROM AUTHOR]

This research was aimed to investigate 16 species belonging to the genus Euphorbia in order to enrich the Iraqi flora with diagnostic characteristics of this genus depending of the surface covering of leaves, stems and floral parts. The studied species were collected from Baghdad, Najaf, Karbala, Wasit, Diyala, Irbil, Kirkuk and Basrah in the growing seasons 2019/2020. These species are: Euphorbia. shehbaziana, E. denticulate Lam, E. craspedia Boiss., E., kete, E. pulcherrima, E. cyathophora Murray. E. granulata Forssk., E. helioscopia L., E. hirta L., E. hypericifolia L., E. milli Des Moul., E. puplus L., E. heterophylla L., E. prostrata Aiton., E. microsphaera Boiss. and E. macrocarpa (Prokh.) Krylov. Results showed variations in types of trichomes which were glandular (stalked or sessile) or eglandular . The stalked glandular trichomes appeared only on the leaf and stem surfaces of E.craspedia and on the leaf surface of E.hirta. They were sessile glandular on the stem and floral surfaces of E.craspedia and leaf and floral part surfaces of E.cyathophora as well as floral parts of both E.hypericifolia and E.milli.The plant parts of the same plant vary from glabrous to hairy. Some of the species do not have any type of trichomes in all the studied parts. These species were E. heterophylla, E. prostrata, E. microsphaera and E. macrocarpa. [ABSTRACT FROM AUTHOR]

Cyphostemma hypoleucum (Harv.) Desc. ex Wild & R.B. Drumm is a perennial climber, indigenous to Southern Africa, and belongs to the Vitaceae. Although there have been many studies of Vitaceae micromorphology, only a few taxa have been described in detail. This study aimed to characterize the micro-morphology of the leaf indumentum and determining its possible functions. Stereo microscope, scanning electron microscope (SEM), and transmission electron microscope (TEM) were used to produce images. Micrographs of stereomicroscopy and SEM showed the presence of non-glandular trichomes. In addition, pearl glands were observed on the abaxial surface using a stereo microscope and SEM. These were characterized by a short stalk and a spherical- shaped head. The density of trichomes decreased on both surfaces of leaves as the leaf expanded. Idioblasts that contained raphide crystals were also detected in tissues. The results obtained from various microscopy techniques confirmed that non-glandular trichomes serve as the main external appendages of the leaves. Additionally, their functions may include serving as a mechanical barrier against environmental factors such as low humidity, intense light, elevated temperatures, as well as herbivory and insect oviposition. Our results may also be added to the existing body of knowledge with regard to microscopic research and taxonomic applications. [ABSTRACT FROM AUTHOR]

We use Helianthemum oelandicum subsp. oelandicum as a model for studies of mechanisms shaping the diversity in a rapidly radiating lineage of the H. oelandicum aggregate. Locally, correlations between drainage conditions (using GIS to measure variation in the micro-topography on the more or less horizontal bedrock) and frequency of alleles of Mendelian genes for pubescence indicated that hairs are markers of adaptation to the unique environmental conditions (drought and periodic flooding) on the alvar habitats of Öland. An allozyme study showed that 1 and 4% of the genetic diversity is partitioned among two varieties and natural populations, respectively. F ST for hair alleles was up to ten time greater than F ST for allozymes. Öland rose above sea level after the LGM, which makes it possible to date the onset of the post-glacial diversification on the island. Only two, mainly allopatric, plastid DNA haplotypes were detected, H1 and H2. The southern Helianthemum oelandicum subsp. oelandicum var. canescens has only H1, whereas the more widespread var. oelandicum possesses both haplotypes. A restricted occurrence of haplotype H1 in the core area of var. oelandicum in the central Öland, coincided with the highest elevation on the island, probably representing the post-glacial arrival of the species on the island. [ABSTRACT FROM AUTHOR]

ABSTRACT The present survey of leaf-blade trichomes of Mendoncia used SEM and light microscopy to investigate the diversity of trichome types in Neotropical and Paleotropical species of the genus. The eglandular trichomes are filiform, uniseriate, with asymmetric epidermal cells arranged radially around the trichome, these epidermal cells may be short or elongated, oriented in two groups. These cells, when elongated, are covered with epicuticular wax, forming smooth thick plates. African species have dendritic but not stellate trichomes. Character states such as number and length of basal cells were shown to overlap within the same species and therefore their use in isolation is not recommended for subgeneric classification of Mendoncia. Neotropical Mendoncia trichomes with well-developed epidermal cells arranged radially around the trichome appear to be unique to this group, without parallel in other plant families.

Croton gratissimus (Lavender croton) possesses three distinct secretory structures. These include lepidote and glandular trichomes and non-articulated unbranched laticifers. The lepidote trichomes form a dense indumentum on the abaxial surface of the leaves and canopy the glandular trichomes. Although assumed to be non-glandular, transmission electron microscopy (TEM) indicated high metabolic activity within the stalk and radial cells. Glandular trichomes are embedded in the epidermal layer and consist of a single cell which forms a prominent stalk and dilated head. Laticifers occur on the mid-vein of leaves and are predominantly associated with vascular tissue. In the stems, laticifers are associated with the phloem and pith. Both trichome types and laticifers stained positive for alkaloids, phenolic compounds, and lipids. Positive staining for these compounds in lepidote trichomes suggests their involvement in the production and accumulation of secondary metabolites. These metabolites could provide chemical defense for the plant and potentially be useful for traditional medicine. [ABSTRACT FROM AUTHOR]

Cyphostemma hypoleucum (Harv.) Desc. ex Wild & R.B. Drumm is a perennial climber, indigenous to Southern Africa, and belongs to the Vitaceae. Although there have been many studies of Vitaceae micromorphology, only a few taxa have been described in detail. This study aimed to characterize the micro-morphology of the leaf indumentum and determining its possible functions. Stereo microscope, scanning electron microscope (SEM), and transmission electron microscope (TEM) were used to produce images. Micrographs of stereomicroscopy and SEM showed the presence of non-glandular trichomes. In addition, pearl glands were observed on the abaxial surface using a stereo microscope and SEM. These were characterized by a short stalk and a spherical- shaped head. The density of trichomes decreased on both surfaces of leaves as the leaf expanded. Idioblasts that contained raphide crystals were also detected in tissues. The results obtained from various microscopy techniques confirmed that non-glandular trichomes serve as the main external appendages of the leaves. Additionally, their functions may include serving as a mechanical barrier against environmental factors such as low humidity, intense light, elevated temperatures, as well as herbivory and insect oviposition. Our results may also be added to the existing body of knowledge with regard to microscopic research and taxonomic applications.

In this study, the carotenoid profiles and content in 132 cultivars of yellow-flesh peach having different fruit developmental periods (short, middle, and long), fruit surface indumenta (glabrous and pubescent skin), and flesh colors (yellow, golden, and orange) were investigated. We simultaneously analyzed and compared the levels of five carotenoids (lutein, zeaxanthin, β-cryptoxanthin, α-carotene, and β-carotene) through high-performance liquid chromatography. Large differences in carotenoid content among germplasms were observed, with coefficients of variation ranging from 21.24% to 67.78%. The carotenoid content, from high to low, was as follows: β-carotene > zeaxanthin > α-carotene > β-cryptoxanthin > lutein. We screened several varieties with high carotenoid content, including zeaxanthin in 'Ruiguang2', β-cryptoxanthin in 'NJN76' and 'TX4F244C', and β-carotene and total carotenoids in 'Jintong7', '77-26-7', and '77-20-5'. A longer fruit developmental period was associated with greater β-carotene accumulation but lowered the zeaxanthin and β-cryptoxanthin accumulation. The zeaxanthin, β-carotene, and total carotenoid concentrations significantly increased as the flesh color deepened, but the lutein and α-carotene levels remained similar among the three flesh colors. The classification index of the indumenta significantly affected the β-carotene and total carotenoid content (p < 0.05) and was higher in pubescent than glabrous skin. [ABSTRACT FROM AUTHOR]

Pterocephalus (Caprifoliaceae) consists of 30 species worldwide, mainly distributed in the temperate regions of the northern hemisphere, of which 14 species were reported from Iran, including five endemic ones. In this study, 35 leaf-related traits and 30 peduncle-related traits were investigated by light microscopy of 15 samples from 11 Iranian species of Ptreocephalus. Our results showed that there were two types of midrib, six types of leaf indumentum and five types of peduncle indumentum. Crystalized calcium oxalate was observed in the leaves and peduncles of most species except in P. plumosus and P. brevis. The profiles of the peduncles were hexagonal, circular or elliptical. The vascular cylinder shape varied from circular to sinuate form. P. wendelboi, with a very different morphology as compared with other species, also exhibited different anatomical characters. The hexagonal sections of peduncle in P. ghahremanii and P. kurdicus and two samples of P. szovitsii were found to be very similar. However, the mentioned characters were found to be less informative or charachterisation of other species. In conclusion, the results showed that the anatomical characters of the leaves and peduncles might have some taxonomic importance in the identification of some species of the genus Pterocephalus.

Croton gratissimus (Lavender croton) possesses three distinct secretory structures. These include lepidote and glandular trichomes and non-articulated unbranched laticifers. The lepidote trichomes form a dense indumentum on the abaxial surface of the leaves and canopy the glandular trichomes. Although assumed to be non-glandular, transmission electron microscopy (TEM) indicated high metabolic activity within the stalk and radial cells. Glandular trichomes are embedded in the epidermal layer and consist of a single cell which forms a prominent stalk and dilated head. Laticifers occur on the mid-vein of leaves and are predominantly associated with vascular tissue. In the stems, laticifers are associated with the phloem and pith. Both trichome types and laticifers stained positive for alkaloids, phenolic compounds, and lipids. Positive staining for these compounds in lepidote trichomes suggests their involvement in the production and accumulation of secondary metabolites. These metabolites could provide chemical defense for the plant and potentially be useful for traditional medicine.

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In this study, the carotenoid profiles and content in 132 cultivars of yellow-flesh peach having different fruit developmental periods (short, middle, and long), fruit surface indumenta (glabrous and pubescent skin), and flesh colors (yellow, golden, and orange) were investigated. We simultaneously analyzed and compared the levels of five carotenoids (lutein, zeaxanthin, β-cryptoxanthin, α-carotene, and β-carotene) through high-performance liquid chromatography. Large differences in carotenoid content among germplasms were observed, with coefficients of variation ranging from 21.24% to 67.78%. The carotenoid content, from high to low, was as follows: β-carotene > zeaxanthin > α-carotene > β-cryptoxanthin > lutein. We screened several varieties with high carotenoid content, including zeaxanthin in ‘Ruiguang2’, β-cryptoxanthin in ‘NJN76’ and ‘TX4F244C’, and β-carotene and total carotenoids in ‘Jintong7’, ‘77-26-7’, and ‘77-20-5’. A longer fruit developmental period was associated with greater β-carotene accumulation but lowered the zeaxanthin and β-cryptoxanthin accumulation. The zeaxanthin, β-carotene, and total carotenoid concentrations significantly increased as the flesh color deepened, but the lutein and α-carotene levels remained similar among the three flesh colors. The classification index of the indumenta significantly affected the β-carotene and total carotenoid content (p < 0.05) and was higher in pubescent than glabrous skin.

Nepeta are widely distributed worldwide and in different parts of Iran where seventy-nine species were registered. The essential oil of these aromatic plants, which accumulates and secrets by trichomes, has been used in medicinal and industrial products. In addition, these epidermal structures can be used as taxonomic traits. We examined the morphology and density of leaves trichomes of twelve Nepeta species using the light and scanning electron microscopes. Three types of indumentum are found in these species, which composed of two main types of glandular: peltate and capitate, and nonglandular; branched and unbranched trichomes. The number of the observed hairs differed between the studied species and analyses of variant test (ANOVA) showed significant variations among some of them. CA-joined plot proved that trichomes could be used as distinguishing characteristic. Therefore, we suggested that the type of indumentum and the most abundant glandular and non-glandular trichomes have high taxonomic value in species identification within the genus.

• Inflorescence morphology and indumentum provide new insights on species limits. • Stemodiopsis rivae sensu stricto does not occur in South Africa. • Stemodiopsis buchananii is a new record for South Africa. • One new species, S. kamundii K. Balkwill is described. The first published record of Stemodiopsis in South Africa was by Dyer in 1975. Since that time, it has been understood that a single species, S. rivae Engl., occurs in South Africa. An analysis of character variation in Stemodiopsis Engl. throughout Africa has revealed that indumentum and inflorescence morphology are important in distinguishing among species. This in turn has revealed that S. rivae Engl. sensu stricto does not occur in South Africa, but that S. buchananii Skan var. buchananii and a new species, S. kamundii K. Balkwill, do. The new species is described and diagnostic characters for the South African species are provided. Both species have a provisional threat status of Least Concern. [ABSTRACT FROM AUTHOR]

Trichomes of 26 species of Alcea (Malvaceae) were investigated using light (LM) and scanning electron microscopy (SEM). The trichomes show a great micromorphological variation, which provides data useful for species delimitation in Alcea. Two basic types of trichomes could be distinguished in Alcea and allied genera: glandular and eglandular. The glandular trichomes could in turn be subdivided into two subtypes: capitate and clavate. The eglandular trichomes could be subdivided into five subtypes: simple, fascicled, stellate, fascicled‐stellate and pluri‐radiate. Characters of taxonomic interest are: trichome density (glabrous to dense), number of arms per trichome, orientation relative to the epidermal surface (appressed to erect) and presence/absence of a stalk. According to the results the species of Alcea can be divided into four informal groups based on trichome types. The results further support the exclusion of the annual Althaea species from the perennial ones and their close relationship to Malva. In addition, a close relationship between perennial Althaea and basal Alcea lineages is supported. Based on the evolutionary framework provided by recent molecular phylogenetic investigations, the following trends can be observed in the Malva alliance: long and narrow‐armed trichomes are primitive in relation to short and thick‐armed trichomes; dense indumentum coverage is primitive in relation to moderately dense or glabrous ones; presence of simple hairs on stem (particularly on leaves) is more advanced than their absence; spreading villous‐stellate and fascicled trichomes are more advanced than appressed stellate ones. Clavate trichomes, which were found exclusively in a few species of Alcea, should be considered as a derived state in relation to capitate ones, and they may provide a synapomorphy for the crown group of Alcea. [ABSTRACT FROM AUTHOR]

Trichomes of 35 species of the genus Convolovulus and one species of the genus Calystegia (C. sepium) were investigated using light and scanning electron microscopy. The trichomes show a great variation, which provides valuable data for sections and species delimitation in Convolvulus. Trichomes of Convolvulus are nonglandular, simple, and basifixed or rarely asymmetrically medifixed. Characters of taxonomic interest were the degree of curviness (straight to spiral), orientation relative to the epidermal surface (appressed to erect), and presence of papillae on trichome surface. The trichomes are divided into two basic types: cylindrical and flattened ribbon-like. Our data provide the additional evidence to include Calystegia in Convolvulus; the former is characterized by glabrous shoots supporting its inclusion in the Convolvulus sect. Convolvulus. Using the evolutionary framework provided by recent molecular phylogenetic investigations, the following trends can be proposed in Convolvulus: long cylindrical trichomes are advanced against the flattened ribbon-like ones, densely papillate trichomes are derived against the nonpapillate or loosely papillate ones, long trichomes are advanced against the short ones, and appressed trichomes are primitive compared with the erect ones. In most investigated species of Convolvulus, a mixture of various kinds of trichomes has been detected, and the level of advancement should be determined by a collective approach. [ABSTRACT FROM AUTHOR]

In the current study, the trichome density and the chemical variation of the hydrodistillated essential oils were determined along the altitudinal gradient in Nepeta sessilifolia, N. heliotropifolia, and N. fissa. The capitate glandular trichomes were predominant in all populations studied. Denser leaves indumentum was observed in high altitude populations of N. heliotropifolia, and in low altitude populations of N. sessilifolia and N. fissa. Moreover, the inter-population chemical polymorphism was detected. In the lower population of N. sessilifolia, spathulenol (14.2%) was the major compound of essential oils. This oil had great amount of oxygenated sesquiterpene (35.3%), while the oil of high altitude population had great amount of diterpenes, namely phytol (32.8%). In N. fissa, the main compound in lower population was β-caryophyllene (33.1%), whereas in the higher population it was caryophyllene oxide (21.5%). In N. heliotropifolia, 1,8-cineole (20.1%) was as the principal oil compound in low altitude population and β-caryophyllene (18.8%) in the high altitude population. We suggested that the amount of different types of monoterpenes decreases along the altitudinal gradient and the amount of oxygenated compounds increases with the elevation.

The study examined indumentum, stomata and pollen morphology of Amaranthus defl exus L., A. hybridus L. and A. retroflexus L. from their Bulgarian populations. Mature pollen and herbarized plant parts have been observed and photographed with a scanning electron microscope (SEM). The indumentum of the three species is of multicellular, un-branched, uniseriate, glandular trichomes. Three types of stomata have been registered -- anomocytic, paracytic and anisocytic with the latter type being the dominant one. Paracytic type were observed only in A. deflexus. Pollen grains were spheroidal, pantoporate, scrabrate, with diameter from 15.4 to 24.2 μm. Among the studied three species differences in pollen morphology have been found in A. deflexus. [ABSTRACT FROM AUTHOR]

Petiole indumentum types of 24 species of the genus Alchemilla were studied using scanning electron microscope (SEM) and digital microscope. All the examined petioles were belonged to the well-developed basal leaves. Two main indumentum types (cylindrical and flat ribbon shape) and seven subtypes including: dense appressed-subappressed subappressed-erecto-patent erecto-patent dense erecto-patent dense horizontal glabri-horizontal-erecto-patent-declinate and declinate trichome were identified. The current results revealed that petiole micromorphological characters were taxonomically informative criteria and could be used in species classification. A key for species identification is presented.

Morphological, chemical and indumentum characteristics of Rhododendron ponticum L. subsp. ponticum collected from Bartın province have been investigated. A detailed description of the species has been prepared and compared with that published in the Flora of Turkey of Davis in a tabular form. The taxonomic and morphological characteristics of the plant material have been described and illustrated by drawings. Indumentum characteristics were also investigated. Volatiles of the flowers were trapped by a dynamic headspace SPME setup and their hexane extract were analyzed by GC/MS. Main components of the headspace trapped volatiles of flowers were characterized as α-pinene (44.5 %), β-pinene (10.8 %), linalool (4 %) and limonene (3.3 %) whereas main components in volatiles of the hexane extract were linalool (19.6 %), phenylethyl alcohol (19.1 %), myrtenol (10.1 %). citronellol (9.4 %) and phenylacetaldehyde (7.8%). [ABSTRACT FROM AUTHOR]

Morphological intermediacy is considered the first evidence of hybridization in many plant studies. However, morphological intermediacy does not always provide hybrid origin and can be a result of divergence. In this study, the authors revised the morphological intermediacy of Erigeron ×huelsenii, a putative hybrid between the Eurasian E. acris s. str. and North American E. canadensis, using the character count procedure, a method that allows distinguishing hybridity from divergence. The measurements were made on herbarium specimens, including 100 specimens of E. acris s. str., 100 specimens of E. canadensis, and 50 specimens of E. ×huelsenii, which were collected in northeastern and southern Poland in 2013-2016. Among the 15 characters selected for the character count procedure, the hybrid showed intermediacy in 12 characters. The deviation was very significant (P < 0.05) and therefore the hypothesis of hybridity was fully accepted. Moreover, details of indumentum and receptacle characters of the hybrid and its parental species were visualized using scanning electron microscopy. The morphological characters of E. ×huelsenii presented in this study seem to be useful in the proper identification of all the hybrids between E. canadensis and E. acris s. l. [ABSTRACT FROM AUTHOR]

Micromorphological investigations on the terpene-producing trichomes at the active secretory stage were performed on leaves and flowers of the Mexican Salvia greggii A. Gray (Lamiaceae), cultivated in Italy. Two types of glandular trichomes are described and compared: peltate, widespread on both the vegetative and the reproductive organs, and medium-stalked capitate, typical of the calyx abaxial side. The histochemical evidences indicate an exclusive terpene production for both morphotypes. TEM survey highlighted several common ultrastructural features that validated the light microscope observations, however a great variability was detected at the plastidome level. Different plastid populations characterized each trichome type, also in relation to the different distribution pattern on the plant epidermis. In the peltates plastids invariably displayed a well-developed internal membrane system and various types of osmiophilic inclusions: on the leaf and the calyx plastoglobuli were also observed, whereas on the corolla abundant starch grains. True leucoplast are only detected in the calyx capitate trichomes. 49 compounds were detected in the essential oil (EO) obtained from the aerial parts, with terpenes representing 98.76% of the total EO, besides negligible amounts of non-terpene derivatives and apocarotenoids. Sesquiterpenes and monoterpenes occurred in similar relative abundances: 52.7% versus 46.1%, respectively. Among sesquiterpenes, γ-muurolene (11.48%) and guaiol (6.15%) dominated for hydrocarbons and oxygenated compounds, respectively. β-pinene (20.24%) prevailed among the monoterpene hydrocarbons, resulting also as the most abundant compound in the essential oil. 1,8-cineole (11.00%) is the dominant compound of the oxygenated monoterpenes. The ultrastructural appearance of the plastidome was linked with the various terpene classes present in the EO profile. We argued that monoterpenes were probably synthetized in the calyx capitate trichomes and the sesquiterpenes in the peltates. [ABSTRACT FROM AUTHOR]

Micromorphological, histochemical and ultrastructural investigations on the indumentum of vegetative and reproductive organs were carried out for Salvia uliginosa Benth. (Lamiaceae). Besides non-glandular hairs, two types of glandular trichomes (peltate and short-stalked capitate) are described and compared with trichomes in other Lamiaceae species. The histochemical findings evidence a similar, complex chemical nature of the secretory products for both types of trichomes: lipids, terpenes, phenols and flavonoids. TEM investigation allows to confirm the preliminary histochemical results. In addition, we report for the first time the phytochemical characterization of the leaf and flower volatile emission profiles and the analysis of the essential oil obtained from the aerial parts. Leaf volatile profile resulted more complex, presenting a total number of constituents almost double compared to that found in the flowers (50 vs 27 compounds, respectively). Leaf VOC profile is characterized by 30 exclusive compounds, dominated by 1,8-cineole (3.84%) and trans -γ-cadinene. Flower VOC profile Exhibits 7 exclusive compounds, among which germacrene D (8.65%) is the most abundant one. Sesquiterpene hydrocarbons represent the major chemical class in both profiles (90.13% in leaves and 92.18% in flowers) and 20 common compounds have been detected: among them δ-elemene, β-caryophyllene, α-humulene and bicyclogermacrene are the dominant constituents, with relative percentages in the range of about 5.00–17.00% for the leaves and of about 9.00-31.00% for the flowers. 49 different compounds were identified in the essential oil obtained from the aerial parts. The extraction yield is 0,02%. Sesquiterpenes represent the most abundant terpene fraction (89.56%). The main compound is bicyclogermacrene (16.30%) followed by germacrene D (14.81%), β-caryophyllene (8.57%) and δ-cadinene (8.47%), among the hydrocarbons. Spathulenol (12.66%) dominates the oxygenated sesquiterpenes. [ABSTRACT FROM AUTHOR]