Cuticle Ornamentation Research Articles

Aerial organ anatomy of <i>Smilax syphilitica (Smilacaceae)</i>

Smilax L. in Brazil is represented by 32 taxa and it is a taxonomically difficult genus because the plants are dioecious and show wide phenotypic variation. The analysis and use of leaf anatomy characters is recognized as a frequently successful taxonomic method to distinguish between individual taxon, when floral material is absent or minute differences in flowers and foliage exist such as in Smilax. The aim of this study was to characterize the anatomical features of the aerial organs in Smilax syphilitica collected from the Atlantic Rainforest, in Santa Teresa-ES and the Smilax aff. syphilitica from the Amazon Rainforest, in Manaus, Brazil. For this, a total of three samples of Smilax were collected per site. Sample leaves and stems were fixed with FAA 50, embedded in historesin, sectioned on a rotary microtome, stained and mounted in synthetic resin. Additionally, histochemical tests were performed and cuticle ornamentation was analyzed with standard scanning electron microscopy. S. syphilitica and S. aff. syphilitica differed in cuticle ornamentation, epidermal cell arrangement and wall thickness, stomata type and orientation, calcium oxalate crystal type, and position of stem thorns. Leaf blades of S. syphilitica from the Amazon Rainforest have a network of rounded ridges on both sides, while in S. aff. syphilitica, these ridges are parallel and the spaces between them are filled with numerous membranous platelets. Viewed from the front, the epidermal cells of S. syphilitica have sinuous walls (even more pronounced in samples from the Amazon); while in S. aff. syphilitica, these cells are also sinuous but elongated in the cross-section of the blade and arranged in parallel. Stomata of S. syphilitica are paracytic, whereas in S. aff. syphilitica, are both paracytic and anisocytic, and their polar axes are directed towards the mid-vein. Calcium oxalate crystals in S. syphilitica are prisms, whereas in S. aff. syphilitica, crystal sand. Thorns occur in nodes and internodes in S. syphilitica but only in internodes in S. af. syphilitica. These features have proven to be of diagnostic value and may support a separation into two species, but future studies are needed to confirm that S. aff. syphilitica is indeed a new taxon.

Comparative leaf anatomy and micromorphology of Psychotria species (Rubiaceae) from the Atlantic Rainforest

The genus Psychotria comprises approximately 2,000 species that are mostly shrubs distributed in forests of the tropics and subtropics. Within the Rubiaceae, Psychotria is well known for its species that produce bioactive alkaloids and for its taxonomic complexity. The anatomical and micromorphological characters of the leaves of P. hoffmannseggiana, P. carthagenensis, P. deflexa, P. glaziovii, P. leiocarpa, P. racemosa, and P. vellosiana were investigated and described to understand the interspecific variation of these species, which will contribute to the systematics of the genus. Principal component analysis (PCA) and unweighted pair group method analysis (UPGMA) indicated four groups based on the presence or absence of some of the characters studied. Dorsiventral mesophyll, hypostomatic leaves, paracytic stomata, organization of the vascular system of the petiole and midrib in an arc and the presence of accessory bundles are common in the species examined and are typical characteristics of the Rubiaceae. The presence of styloid crystals and alkaloids are considered diagnostic characters of Psychotria. Other characteristics used to separate species in the genus are the petiole contour, cuticle ornamentation, and presence of trichomes. The results of the UPGMA cluster analyses indicated that there is similarity between Psychotria (subg. Heteropsychotria) and Palicourea species.

Infection of the Red Palm Weevil (Rhynchophorus ferrugineus) by the entomopathogenic fungus Beauveria bassiana: A SEM study

The Red Palm Weevil (Rhynchophorus ferrugineus) is a devastating pest of palms in the Mediterranean, Middle East, and Eastern countries. No effective control measures are available. R. ferrugineus has been found naturally infected by the entomopathogenic fungus Beauveria bassiana, but its infection process in this host is unknown. We have studied the infection of R. ferrugineus larvae and adults by B. bassiana using dry conidia and conidia suspensions using scanning electron microscopy (SEM). In early stages, SEM revealed acquisition of B. bassiana conidia by cuticle ornamentation in legs, antennae, and elytra of R. ferrugineus adults. Subsequently, conidia germinated and frequent episodes of hyphal/conidial fusion were found. Appressoria, signs of adhesion and cuticle degradation led to penetration (even direct) and colonization of R. ferrugineus hosts by the fungus. B. bassiana conidiophores were found in a R. ferrugineus cuticle, which indicate the completion of the life cycle of the fungus in the insect host. SEM has proven that dry conidia of B. bassiana is an adequate inoculum for R. ferrugineus infection. SEM revealed that conidia of B. bassiana attached to the cuticle of R. ferrugineus can germinate and differentiate appressoria.

Anatomy Studies on Six Mosses in Kanas Nature Reserve

Paraffin sectioning technique and scanning electron microscopy methods were applied to observe six species of masses.The internal structure of stems,leaves and the stratum corneum surface ornamentation,warts growth and micro-hole were compared.The results indicated that the epidermal cells of Rhytidium rugosum(Hedw.) Kindb.have small verrucose on outer wall,while the tandem of the wall adjacent to the surface of the cuticle cell patterns long into parallel bundles;stem axis of the Abietinella abietina(hedw.) fleisch was not obvious,in the back of a rib-like thorns protruding warts,dorsal,ventral surfaces of the side wall warts,was covered like;the epidermal cells wall of Bartramia ithphylla Brid.uplift,holes was not sink,orifice was covered by the cuticle ornamentation;the back surface of leaf crude cell wall of Aulacomnium palustre(Hedw.) Schwagr.warts highlighted by the depression,cuticle ornamentation was banded,leaf faces big belly,and in many cell wall-like interface was open;the epidermal cells of back leave of Hylocommium splendens(Hedw.) B.S.G wart like thorns wide,dorsal,ventral warts rough high,the top of the cell wall with depression;Dorsal,ventral cells irregular depressions adjacent cell wall of Ceratodon purpureus(hedw.) Brid.was a small intensive wart.

Comparative leaf epidermis investigation in species of genus Crataegus L. (Rosaceae) from Bulgaria

AbstractThe leaf epidermis structure of six Crataegus species from Bulgaria has been studied by light and scanning electron microscopy. Cyclocytic stomatal type, different types of simple single trichomes, cuticle ornamentation and waxes are determined. The results allow clear delimitation and identification of the species. Some conjectures about the relationships on inter‐ and intrageneric level and references of epidermal structure with adaptation to various ecological conditions are discussed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Histological characteristics of sugar beet leaves potentially linked to drought tolerance

Water is becoming more and more limiting factor of sugar beet production and the productivity of the crop can be significantly improved by increased drought tolerance. It is therefore a great challenge to assess the degree of variability of anatomical and morphological traits of breeding material with respect to water use efficiency and drought, that can be used as potential markers for selection of sugar beet genotypes with better tolerance to water shortage. To achieve this, the first step is to assess the degree of genetic variability with respect to anatomical and histological features linked to water management in plants, under optimal water supply. Comparative histiological analysis of lamina and petiole was done on 12 sugar beet genotypes which previously showed divergent responses to lack of water in the field. The plants were grown in semi-controlled conditions of a glasshouse, and watered daily. Mircromorphological analyses were done to assess leaf epidermal characteristics, by both light and SEM, and lamina and petiole histological features. The measurements were used to calculate the percentage of individual tissues in relation to the thickness of the lamina, main vein area and petiole area. The general structure of sample variability was established by principal component analysis (PCA), based on correlation matrix. In majority of genotypes the ratio of the size of cells of spongy parenchyma and palisade cells in average was 80%. Low genotypic variability of the studied histological parameters of the lamina and petiole may reflect the narrow genetic base of tested breeding material. The most significant genotypic difference, considering leaf epidermal tissue, was in % of adaxial and abaxial epidermis. The highest found number of stomata per mm 2 on both adaxial and abaxial epidermis was 40% higher than the lowest. During water stress, when stomata are closed, plant survival depends on the amount of water lost through the cuticle. SEM analysis of adaxial epidermis of the lamina show that cuticle varies in texture. Considering the observed genotypic variability in cuticle ornamentation and the fact that plants develop various strategies of adaptation to drought, finding genotypes with increased drought tolerance could be based on the characteristics of the cuticle and epidermis.

Leaf Epidermis Structure in Cydonia Oblonga Mill. (Rosaceae)

ABSTRACTThe leaf epidermis structure of Cydonia oblonga Mill. has been studied by light and scanning electron microscopy. Cuticle ornamentation and waxes have been observed. Simple single trichomes and cyclocytic stomatal type are determined. An attempt to estimate all features of taxonomic value is made and some relationships within subfamily Maloideae are discussed. ncentration 200 μM CdCl2. Glutathione reductase (GR) activity was not detected in algal cells of the all experimental variants

Three species of Skrjabinelazia Sypliaxov, 1930 (Nematoda: Seuratidae) parasitic in Gekkonidae and Lacertidae from South Africa, Europe and Australia

Skrjabinelazia Sypliaxov, 1930 comprises 10 species distinguished by several characters typical of the genus including, among the most important, the presence/absence of spicules, cuticle ornamentation and vesicles, head-shape, the presence/absence of a leaflet crown in the buccal cavity, female tail-shape and male cone-shape. The three samples studied are new species: S. boomkeri n. sp., a parasite of Pachydactylus turneri, Gekkonidae, from South Africa (Klaserie Reserve); S. vozae n. sp., a parasite of Lacerta vivipara, Lacertidae, from France (Cévennes), which is close to two lacertid parasites, S. taurica Sypliaxov, 1930 and L. hoffmanni Li, 1934, respectively from the Crimea and North China (Peking); and S. mawsangelae n. sp. (male unknown), a parasite of Christinus marmoratus, Gekkonidae, from Australia (Pearson Island), which is, surprisingly, distinct from Skrjabinelazia sp. of Angel & Mawson (1968) from the same host in another region (North of Adelaide) of South Australia. Two main groups are distinguished in Skrjabinelazia: the species with spicules which are parasitic in the Lacertidae, and the species with a gubernaculum only which are parasitic in the Gekkonidae. The unique species described from the Iguanidae, S. intermedia (Freitas, 1940) from Brazil (Para), also without spicules, seems to be derived from gekkonid parasites, as it also has an evolved oesophagus with a glandular region, unlike the simple oesophagus seen in the larval stages of Skrjabinelazia.

Contribución al conocimiento de Peperomia (Piperaceae): fruto y semillas

Peperomia Ruiz et Pavón comprende un número indeterminado de especies que se distribuyen en las regiones tropicales y subtropicales de ambos hemisferios. Uno de los motivos que atrae el interés hacia este género es la dificultad para determinar sus especies. En este trabajo se muestran las características microscópicas del fruto y la semilla de 17 especies mexicanas de Peperomia, distribuidas en seis subgéneros (Acrocarpidium, Micropiper, Ogmocarpidium, Rhyncophorum, Sphaerocarpidium y Tildenia ). Las especies se distinguen por los siguientes caracteres del fruto: (a) la ubicación y la inserción del fruto en el raquis, (b) la forma del ovario, (c) la curvatura del fruto, (d) la composición celular del exocarpio y del endocarpio, (e) la forma del estilo, (f) la posición del estigma, (g) la presencia de cristales en el pericarpio, y (h) la ornamentación de la cutícula epidérmica. Se definen caracteres taxonómicos nuevos y se aclaran términos relacionados con la inserción y la apariencia externa del fruto que se utilizan comúnmente para describir el fruto de Peperomia. Las 17 especies presentan un perispermo amiláceo, un endospermo escaso y un embrión poco desarrollado. Se sugiere el estudio de un mayor número de especies para identificar posibles caracteres o estados de carácter adicionales

Anatomia foliar de Tillandsia L. (Bromeliaceae) dos Campos Gerais, Paraná, Brasil

The leaf anatomy of Tillandsia crocata (E. Morren) Baker, T. gardneri Lindl., T. geminiflora Brongn., T. linearis Vell., T. lorentziana Griseb., T. mallemontii Glaziou ex Mez, T. recurvata L., T. streptocarpa Baker, T. stricta Soland ex Sims, T. tenuifolia L., T. usneoides L., and Tillandsia sp. were studied. They occur in the Campos Gerais, State of Parana, southern Brazil. In surface view epidermis presents cells with linear to sinuous anticlinal walls, silica bodies and scales covering anomocytic stomata. Epidermis and first hypodermal layer are lignified. Transversal view reveals below surface stomata, aquiferous parenchyma, longitudinal air canals and collateral vascular bundles with double sheath. These anatomical features are xeromorphic and usually considered as an adaptation to the epiphytic habit of the atmospheric Tillandsia. Moreover, they could be also used for diagnostic purposes. Leaf shape in cross section, cuticle ornamentation, epidermal scale structures, thickening of the epidermal wall cells, stomata distribution, structure and distribution of the aquiferous parenchyma cells, presence of air canals, and size of vascular bundle could help the taxonomic delimitation of the species within the genus.

A comparative study of leaf epidermis in European Corylaceae

AbstractA study of the epidermis of European Corylaceae is presented. All three genera can be distinguished by the leaf epidermis structure. Corylus avellana L. and C. colurna L. differ only in numerical quantitative characters such as trichome frequency and combinations of the trichomes.Carpinus betulus L. and C. orientalis MILL. are very distinct in the structure of the stomatal apparatus, epidermal surface and appearence of anticlinal and periclinal walls. As a rule such large differences are more characteristic of the generic level. Ostrya carpinifolia SCOP. possesses prominently dense cuticular striations on the lower epidermis and acicular trichomes on the upper epidermis. Paracyclic, cyclocytic and laterocytic stomatal types were reported for the first time for the family. Those stomatal types corroborate the hamamelidian relationships of the family. Despite the differences in epidermal structures e.g. a combination of various stomatal types and cuticle ornamentation the investigated species as a whole form a natural evolutionary unit.

Investigations of angiosperms from the Eocene of southeastern North America: samaras of Fraxinus wilcoxiana Berry

Fruits of Fraxinus L. from Eucene sediments of North America constitute the oldest unequivocal macrofossil evidence of the genus, of the subfamily Oleoideae, and of the family Oleaceae. We briefly review North American Paleogene records of Fraxinus, and report the results of a study of 30 samaras of Fraxinus wilcoxiana Berry (including the holotype) from two localities in the Middle Eocene Claiborne Formation of western Tennessee, USA. The diagnosis and description of this species are emended to include new information on its persistent calyx, fruit and seed cuticles, and variation in samara dimensions and morphology. The fossil samaras lack characters used in the systematic grouping of infrageneric taxa, and therefore cannot be assigned to a modern section or subsection of the genus. However, samara cuticle bears striae and two distinct classes of peltate trichomes useful in confirming the oleaceous affinities of the fossils. Fraxinus wilcoxiana samaras are essentially modern in terms of their morphology, seed size, single basal pendulous seed, and cuticle ornamentation. The presence of Fraxinus in Paleogene sediments attests to an early divergence of the subfamilies Oleoideae (basal chromosome number 23) and Jasminoideae (basal chromosome number 11, 12 or 14). Fraxinus wilcoxiana samaras also demonstrate that anemochory (wind dispersal of disseminules) is an ancient dispersal strategy among Oleaceae.

A comparison of some environmental adaptations of the littoral collembolansAnuridella marina(Willem) andAnurida maritima(Guérin)

Cuticle structures of A. marina and A. martima are discussed, the differences are correlated with a greater tolerance of desiccation in A. maritima. The cuticle ornamentation of A. maritima can trap a layer of water-saturated air thus slowing down water loss and allowing it to forage in the drier upper littoral, while A. marina, without a layer of water saturated air, is confined to more humid habitats in the lower littoral. Both species have a compressible macroplastron supported by major tubercles, as well as a much thinner microplastron supported by minor tubercles which is more resistant to wetting by pressure and surfactants. The plastrons are shown to be preadaptations to the littoral zone.

Seed Coat Structure of Sesbania Species

Summary The seed coat structure of Sesbania bispinosa and Sesbania punicea were investigated. Both species have seed coat structures which are typical of legume seeds. Differences do however, exist in their cuticle ornamentation, macrosclereid, and hour-glass cell layers. The macrosclereid cells of S. bispinosa are packed much tighter than those of S. punicea . This compaction may explain why the seed coats of S. bispinosa are less permeable than those of S. punicea . The integrity of the macrosclereid layer is apparently vital to seed coat impermeability. This is shown by the fact that in «rust» coloured seeds of both species, where the macrosclereid layer is interrupted by triangular cavities, the seeds were always permeable.