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Cross section of the leaf-ansamble Abies alba (A, x 60), Larix decidua (A, x 150) and Picea abies(B, x 120): e-epidermis, m-mesophyll, rd-resin duct, vb-vascular bundle.
Source publication
The paper is a part of a complex study of some Gymnospermae species leaf. The article presents a comparative study concerning the leaf histoanatomical structure of two Pinaceae species: Larix decidua Mill. and Picea abies (L.) Karsten. The species leaves in cross section exhibit a one-layered epidermis, covered by a waxy cuticle, a schlerenchymatou...
Contexts in source publication
Context 1
... section of the leaf exhibit a more or less elliptical shape for Larix decidua and an elliptical 4-coasted shape for Picea abies (Fig. 1, A, B). Such as other gymnosperms ( Bercu et al., 2010), the epidermis consists of a single layer of iregular in size lignified cells, covered by a continuous waxy cuticle for both species. ...
Context 2
... continuity is interrupted by the presence of 2-3 for Larix decidua and 3-4 for the other species engrossed stomata with substomatal cavity, smaller for Larix decidua and larger in Picea abies leaf (Fig. 2, A, B). The two studied species show a homogenous mesophyll with highly wrinkled walled cells, increasing a large surface of absorption (Fig. 1, A, B). As Watson & Dallwitz (2008) reported, for some Pinaceae species leaves, just below the hypodermis, the two species show two longitudinal resin ducts more or less circular in shape, formed such as other coniferous species, by the disintegration of the cells (lysigenous cavities) (Bercu & Bavaru, 2002;Esau, 1965;Raven, 1994). They are ...
Citations
... The anatomical structure of extant conifer leaves has been extensively studied (Ghouse and Yunus, 1974;Hu and Yao, 1981;Yao and Hu, 1982;Wu and Hu, 1997;Bercu et al., 2010;Liesche et al., 2011;Bercu and Popoviciu, 2013). Anatomical characteristics, including the epidermal structure, presence or absence of the hypodermis, degree of differentiation of the mesophyll, occurrence of an endodermis or vascular bundle sheath, transfusion tissue type, number and spatial position of the vascular bundle, number and distribution of resin canals, and the presence of sclereid or sclerenchyma, are regarded as critical criteria in systematics and evolutionary studies of conifers (Yao and Hu, 1982). ...
Leaves are important vegetative organs of plants. However, our knowledge of fossil conifer leaves has been mostly obtained from compression-impression specimens. Compared with the abundant impression-compression leaf fossils, permineralized conifer leaf fossils with preserved cellular details are extremely rare. Therefore, leaf anatomies of fossil conifers remain poorly understood. Here, we describe permineralized leaves of a fossil conifer, Ningxiaites specialis Feng 2012, from the Lopingian Sunjiagou Formation of Northwest China. The leaves are linear and helically arranged on shoot axis. They are characterized by a single vascular bundle surrounded by transfusion tissue, a single-layered endodermis, a thick mesophyll, and a single-layered epidermis. Tracheids in the vascular bundle exhibit helical and scalariform thickenings. The transfusion tissue is of the Pinus-type and composed of transfusion tracheids and transfusion parenchyma. The mesophyll comprises palisade and spongy tissues. The palisade mesophyll consists of thin-walled elongate cells, and is present on the adaxial side of the leaf. The spongy mesophyll comprises subcircular to subrectangular shaped cells and is present on the abaxial side. The hypodermis is discontinuously present beneath the adaxial epidermis and possesses two to three layers of sclerenchyma cells. The epidermis consists of a single layer of rectangular parenchyma covered by a thick cuticle with abundant cylindrical papillae. Stomata are predominantly present on the adaxial leaf surface and are arranged in parallel rows. This is the first report on the leaf anatomy of a Paleozoic conifer from the North China Block and sheds new light on the evolutionary history of conifers.
... Одной из задач исследования являлось установление особенностей локализации эфирного масла в корнях ели обыкновенной. В древесной зелени и шишках ели эфирное масло локализовано преимущественно в смоляных ходах [20,21]. От особенностей локализации эфирного масла может зависеть заготовка, хранение и способ получения эфирного масла из данного сырья. ...
... One of the research tasks was to establish the peculiarity of localization of the essential oil in Eu-ropean Spruce roots. The essential oil of the woody greens and cones is localized predominantly in resin currents [20,21]. The preparation, storage and method of obtaining the essential oil from this raw material can depend on the peculiarity of the essential oil localization. ...
The article is devoted to the study of essential oil extracted from the roots of European Spruce (Lat. Picea abies).The aim is to establish the component composition of the essential oil and the peculiarities of its localization in the roots of European Spruce.Materials and methods. The objects of the study are the roots of European Spruce not longer than two centimeters in diameter, peeled and dried. The study of their anatomical signs was carried out according to the methodology of the State Pharmacopoeia of the Russian Federation (the XIII-th edition) with the”Biomed-6” microscope using the DCN 510 nozzle. The essential oil was obtained by hydrodistillation of European Spruce roots using the device of Clevenger by Method 2 of the State Pharmacopoeia of the Russian Federation (the XIII-th edition). The component composition of the essential oil was determined by an Agilent 7890A gas-liquid chromatograph with an Agilent 5975C mass-selective detector.Results and discussion. As a result of the microscopic examination of the roots of European Spruce, it was established that the essential oil is localized mainly in resinous courses located in the wood of the root. In the central part of the root, resin moves are of a larger diameter. More than 18 components were found in the essential oil of European Spruce roots, 14 of them were identifi ed. The main component of the essential oil is sesquiterpene lactone – tanbergol.Conclusion. The essential oil of European Spruce roots has a unique component composition that includes components not characteristic for the essential oil of spruce greenery. The difference in the component composition indicates the difference in properties and pharmacological activity. Further studies are of interest for determining the prospects of using European Spruce roots.
Gymnosperms are a very old and small group of plants compared to angiosperms. Contemporary science recognizes about 650 extant conifers worldwide. This review focuses on species of the Pinaceae family found in Europe. There are 23 species from the genera Abies, Larix, Picea, and Pinus. Some of them are widespread in Europe, but others have fragmented and limited distribution and are classified as relic, endemic, or endangered. The aim of this review is providing cumulative information about the variability of needle morpho-anatomy, terpenes, and n-alkanes, as well as the genetics of the Pinaceae species, native to Europe. The first morpho-anatomical examinations of needles were conducted in the 19th century. A lot of species have been investigated up to now, but the population variability of many conifer species is still not known. The composition and abundance of terpenes differ between genera and families but also within the same genus, pointing to their taxonomic importance. n-Alkanes on the needle wax surfaces of conifers are sometimes very useful markers of species and population variability. The most abundant n-alkanes in Abies species are nonacosane (C29), hentriacontane (C31), or heptacosane (C27), whereas in Larix decidua and the majority of Picea species, C31 is predominant. C31 and C29 are the dominant n-alkanes in the genus Pinus. The most extensive population-genetic studies of European representatives of the Pinaceae family have focused on Abies alba, Picea abies, Pinus nigra, and Pinus sylvestris, but also examined endemic species such as Abies borisii-regis, A. cephalonica, A. nebrodensis, and Picea omorika. These studies hold significant practical value in assessing species’ evolutionary potential, devising strategies for long-term species conservation, identifying centers of diversity, detecting relict and ancestral populations, unveiling cryptic species and hybrids, and elucidating the taxonomic significance of species. These investigations are of great value not only on the biodiversity level, but also on the levels of ecology, physiology, taxonomy, and evolution.
The structure of needle mesophyll and the forms of assimilative cells in the genus Larix species are discussed on the example of L. gmelini var. gmelini, L. decidua, L. kaempferi and L. sibirica. Needle samples were fixed in the Gammalund’s mixture. The study of the mesophyll was carried out on transverse, paradermal and radial sections of the middle part of the needles using a light microscope. To clarify the shape of chlorenchyma cells, macerated preparations were used. It is shown that the needle mesophyll in Larix species mainly consists of large cells of complex shape, which touch their convex parts or ends to form a well-developed system of intercellular spaces, which may comtribute to intense gas exchange. Different variants of flat folded, flat cellular and more complicated folded-cellular assimilative cells are described. The flat folded cells are characterized by a variety of lobed configurations on transverse sections and elongated oval projections on radial sections. The flat cellular cells are found on needle longitudinal sections of and consist of cellular links facing both perpendicular (cellular cells of the first group) and parallel (cellular cells of the second group) to the leaf surface. The folded-cellular cells combine transverse folded contours and longitudinal cellular outlines. In the needle mesophyll of the studied Larix species, weak differentiation into palisade and spongy parenchyma is observed; the cells of the middle part (median cells) are additionally distinguished between them. The palisade tissue is formed mainly by cellular cells of the first group, the spongy tissue by cellular cells of the second group. The median cells are located on both sides of the vascular bundle along a large needle radius; they can be either flat and slightly folded, or folded-cellular. The studied Larix species are similar in th esize of assimilative cells and the structure of the needle mesophyll; the main differences between them are related to the features of cell dissection both in transverse and longitudinal directions.
