Effect of gamma-irradiation and colchicine on cell division and differentiation of xylem elements in citrus limon juice vesicle cultures

International Nuclear Information System (INIS)

Khan, Aysha; Chauhan, Y.S.

1999-01-01

The effects of varying doses of gamma irradiation on cell division and cytodifferentiation of tracheary elements in cultured juice vesicles of Citrus limon (L) Burmann var. Assam lemon were investigated. Low radiation doses stimulated cell division and differentiation of xylem fibres, sclereids and tracheids in explants given up to 10 Gy of gamma rays. Although cell division and cytodifferentiation of fibers and sclereids occurred in explants exposed to 150 dose of Gy radiation, the intensity of differentiation was much less than that induced by 10 Gy radiation dose. Amongst the differential elements, tracheids were more sensitive to radiation than fibres and sclereids. The requirement of cell division for differentiation of xylem cells was also studied by using different concentrations of colchicine in Citrus limon juice vesicle cultures. It was found that the low concentrations of colchicine permitted normal cell division and also resulted in normal differentiation of xylem cells; higher colchicine concentration, however, inhibited cell division as well as differentiation and resulted in an abnormal differentiation of tracheary element. A positive correlation between intensity of nucleic acid staining and cell division in both the above-mentioned experiments was qualitatively confirmed by Azur B staining test of nucleic acid. Thus, it was concluded that juice vesicle parenchyma cells go through nucleic acid synthesis, followed by cell division before differentiation. (author)

Memecylon clarkeanum Cogn. (Melastomataceae - a Threatened Species, New Record for India

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Ambikabai Raghavanpillai Sivu

2012-09-01

Full Text Available Memecylon clarkeanum Cogn., an endemic and threatened species of Sri Lanka characterized by narrowly filiform foliar sclereids is reported and described as a new record for India from Wayanad, Kozhikode, Malappuram and Palakkad districts of Kerala.

Notes on Magnoliaceae with a revision of Pachylarnax and Elmerrillia and the Malesian species of Manglietia and Michelia

NARCIS (Netherlands)

Nooteboom, H.P.

1985-01-01

After the general chapters, mainly based on literature and dealing with wood anatomy, characters of the leaf epidermis and foliar sclereids, embryology and chromosome numbers, phytochemistry, and characters of the fruit, the generic delimitation of subfamily Magnolioideae is discussed. Paramichelia

Microstructure of Desmanthus illinoensis

Science.gov (United States)

Structure and histochemistry of mature seeds of Desmanthus illinoensis (Illinois bundle flower) show that the seed has typical legume structure. The seed can be separated into two major fractions including the seed coat/endosperm and the embryo. The seed coat consists of a cuticle, palisade sclereid...

Review

NARCIS (Netherlands)

Baas, P.

1993-01-01

With over 80 original publications on foliar sclereids, published in the last 30 years, Dr. T. Ananda Rao is a well qualified author for a compendium on the subject. The book consists of a general and a special part. The former includes a historical and methodological introduction, a major chapter

two genera of myrtaceae

Indian Academy of Sciences (India)

The present paper deals with the sclereids of three species of Syzygium, S. cumini, Linn. Skeels., S. nodosum. Miq., and S. cinereum Wall, and in Eucalyptus tereticornis Sm. Austral. Metcalfe and Chalk (1950) have already drawn attention to the occurrence of stone-cells in the pith and cortex of the stems of some species of ...

Untitled

Indian Academy of Sciences (India)

they have nothing to do with transport of water or food and in view of their dead and lignified nature the only inference is that they serve to give mechanical strength to the tissues. This is borne out of the fact that in these three species, the greatest frequency of the Sclereids is met within the species, which has the toughest ...

Ultrastructural Studies on Root Nodules of Pithecellobium dulce (Roxb.) Benth. (Fabaceae)

OpenAIRE

Raiha Qadri; A. Mahmood; Mohammad Athar

2007-01-01

Ultrastructural studies were conducted on Pithecellobium dulce (Roxb) Benth. root nodules collected from trees growing under natural conditions. Rhizobial infection on root surface of P. dulce started with curling of root hair. Both curled and straight root hairs were observed. The internal structure of a mature nodule showed an epidermis, cortex, vascular region and a bacteriod region. Vascular bundles were amphicribral. A distinct periderm consisted of sclereid tissue could be observed in t...

Leaf structural adaptations of two Limonium miller (Plumbaginales, Plumbaginaceae taxa

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Zorić Lana N.

2013-01-01

Full Text Available Limonium gmelinii (Willd. O. Kuntze 1891 subsp. hungaricum (Klokov Soó is Pannonian endemic subspecies that inhabits continental halobiomes, while Limonium anfractum (Salmon Salmon 1924 is one of the indicators of halophyte vegetation of marine rocks and its distribution is restricted to the southern parts of Mediterranean Sea coast. In this work, micromorphological and anatomical characters of leaves of these two Limonium taxa were analyzed, in order to examine their adaptations to specific environmental conditions on saline habitats. The results showed that both taxa exhibited strong xeromorphic adaptations that reflected in flat cell walls of epidermal cells, thick cuticle, high palisade/spongy tissue ratio, high index of palisade cells, the presence of sclereid idioblasts in leaf mesophyll and mechanical tissue by phloem and xylem. Both taxa are crynohalophytes and have salt glands on adaxial and abaxial epidermis for excretion of surplus salt. Relatively high dimensions of mesophyll cells, absence of non-glandular hairs and unprotected stomata slightly increased above the level of epidermal cells, are also adaptations to increased salinity. [Projekat Ministarstva nauke Republike Srbije, br. 173002

Ontogenia e estrutura do pericarpo de Prestonia riedelii (Müll. Arg. Markgr. (Apocynaceae Pericarp ontogeny and structure of Prestonia riedelii (Müll. Arg. Markgr. (Apocynaceae

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Shesterson Aguiar

2009-09-01

Full Text Available O trabalho teve por objetivos descrever a ontogenia e estrutura do pericarpo de P. riedelii, visando fornecer subsídios aos trabalhos taxonômicos, filogenéticos e ecológicos realizados para família. Flores e frutos em diferentes estádios de desenvolvimento foram fixados em FAA, incluídos em resina plástica, seccionados com 10 ìm e corados com azul de toluidina para análise estrutural. O fruto de P. riedelii é um folicarium, sendo formado por dois frutículos do tipo folículo. O epicarpo, originado da epiderme externa do ovário, é formado por uma camada de células epidérmicas de cutícula espessa e tricomas tectores multicelulares e unisseriados. O mesocarpo, originado a partir do desenvolvimento do tecido fundamental, é formado por várias camadas de células parenquimáticas, feixes vasculares, fibras não lignificadas e laticíferos. O endocarpo sensu lato é formado por duas camadas de esclerócitos de disposição cruzada, que se originam da epiderme interna do ovário e de uma camada de células do tecido fundamental. A deiscência de cada folículo é marginal e o processo de deiscência envolve um conjunto de características anatômicas, como células de parede delgada e sinuosa formando a linha de deiscência, fibras não lignificadas no mesocarpo e esclerócitos de disposição cruzada no endocarpo.The aim of this work was to describe the morphology and ontogeny of P. riedelii fruits to aid in taxonomic, ecological and phylogenetic studies in Apocynaceae. Fruits were fixed in FAA, embedded in plastic resin, sectioned at 10 ìm and stained with toluidine blue, for structural analysis. The fruit of P. riedelii is a follicarium, with two follicular fruitlets. The epicarp is one-cell-layered, with trichomes and thick cuticle. The mesocarp, originating from fundamental ovary tissue, is parenchymatous with laticifers, non-lignified fibers and vascular bundles. The endocarp sensu lato is two-celllayered of crossed sclereids

Botanical and genetic characters of Erythrina × neillii cultivated in Egypt

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Salma K. Gabr

Full Text Available Abstract Erythrina × neillii Mabberley & Lorence, Fabaceae, is a sterile hybrid between E. herbacea L. and E. humeana Spreng. Nothing was traced about its genetic, macro and micromorphology. Therefore, it was deemed of interest to study its botanical characters, in addition to the DNA fingerprint to help in the identification of the plant. The anatomical characters of the old stem and its bark are characterized by the presence of cork cells, bast fibers and sclereids. Pericycle is sclerenchymatous forming crystal sheath. The epidermises of the leaf and young stem are characterized by the presence of anomocytic and paracytic stomata, non-glandular, unicellular and multicellular two armed hairs, and glandular club shaped hair. Calcium oxalate is present in the form of crystal sheath and prisms. Secretory cavities are distributed in the phloem and cortex. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE was used as one of the molecular methods to differentiate between the samples of Erythrina. The DNA of Erythrina was extracted and analyzed using seven-mer random primers. Randomly Amplified Polymorphic DNA were recognized. This characterization allows certification of the authenticity of Erythrina × neillii, in order to provide quality control for the plant.

A study of the morphoanatomical characters of the leaves of Chamaecrista (L. Moench sect. Apoucouita (Leguminosae-Caesalpinioideae

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Ítalo Antônio Cotta Coutinho

2016-01-01

Full Text Available ABSTRACT Little attention has been paid to species of Chamaecrista sect. Apoucouita (Leguminosae-Caesalpinioideae, especially regarding anatomical studies. When only vegetative material is available, the identification of such species may be difficult. Additionally, vegetative material of some species of C. sect. Apoucouita may be even harder to identify because they can resemble species of Inga Mill. (Leguminosae-Mimosoideae. The present study focused on recognizing morphoanatomical characters of leaves that are taxonomically useful for the species of C. sect. Apoucouita by employing standard anatomical techniques. The arrangement of the vascular system in the petiole/rachis, dorsiventral mesophyll, mucilage idioblasts in the epidermis of leaflets and hypostomatic leaves were some of the characters shared by all species studied. Length of the petiole, position and type of extrafloral nectaries, leaflet venation, presence and type of papillae on the epidermis of the leaflet blades and sclereids in the mesophyll were some of the characters useful in the distinction of taxa. The vascular arrangement of the petiole/rachis is a promising character in the distinction of species of C. sect. Apoucouita and Inga. Based on morphoanatomical data, the taxonomic revision of some species and varieties ascribed to C. sect. Apoucouita is suggested.

Structure and histochemistry of medicinal species of Solanum

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Laudineia J. Matias

Full Text Available ABSTRACT Studies on native medicinal plants strengthen initiatives to preserve the environments where those species naturally occur, many of them already strongly menaced even before their potential to humankind is known. Root and stem barks, leaves, and pericarps samples of Solanum agrarium Sendtn., S. lycocarpum A. St.-Hil., S. palinacanthum Dunal, S. paniculatum L., and S. stipulaceum Roem. & Schult., species that occur in the Cerrado (Brazililan savanna were processed according to common light microscopy techniques for structural analysis, and histochemical tests were performed to locate and identify classes of chemical compounds. The distinctive features identified were low concentration of crystal sand in the root and stem, presence of terpene resin in the root, and absence of hypodermis in the leaf, in S. agrarium; bright spots (group of sclereids in the root, isobilateral mesophyll, thickened cell walls with hemicelluloses and strong aroma in the fruit, in S. lycocarpum; high concentration of crystal sand in the root and stem, oval-shaped limb, presence of isolated crystals in the exocarp, in S. palinacanthum; strong sclerification and rays with great height in the root and stem, in S. paniculatum; and accumulation of soluble protein in the root and stem, presence of conspicuous membranaceous stipules, absence of spiniform trichomes, in S. stipulaceum. This work identifies distinctive structural features, its ecological importance, and determines the distribution of secondary compounds associated with the medicinal properties reported for these species and contributes to the conservation of the natural environments where they occur.

Determinação de compostos fenólicos em amostras comerciais de chás verde e preto - Camellia sinensis (L. Kuntze, Theaceae = Determination of phenolic componds in commercial samples of green and black tea - Camellia sinensis (L. Kuntze, Theaceae

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Airton Vicente Pereira

2009-04-01

Full Text Available O chá de Camellia sinensis é rico em compostos fenólicos antioxidantes, responsáveis por efeitos benéficos à saúde humana. Neste trabalho, foram realizadas as determinações da concentração de fenóis totais e flavonoides de sete amostras comerciais dos chás preto e verde. Os teores de fenóis totais variaram de 4,80 a 26,60 mg de pirogalol g-1 de amostra e os de flavonoides, de 0,46 a 1,10 mg de quercetina g-1 de amostra. A análise anatômica do conteúdo das amostras permitiu caracterizar a autenticidade dos produtos,observando-se os marcadores anatômicos típicos da espécie (estômatos anomocíticos, tricomas tectores unicelulares, mesofilo dorsiventral, drusas de oxalato de cálcio e esclereides.The tea from Camellia sinensis (green tea and black tea is rich in antioxidant phenolic compounds, responsible for beneficial effects to human health. In this work, determinations were carried out on theconcentration of total phenols and flavonoids in seven commercial samples of black tea and green tea. The samples presented concentrations of total phenols varying between 4.80 and 26.60 mg of pyrogallol g-1 and concentrations of flavonoids from 0.46 to 1.10 mg of quercetin g-1. With the purpose of characterizing the authenticity of the product contained in the sachets, the samples were fixed for histological studies. The samples presented the typical anatomical markers of the species (anomocytic stomata, unicellular non-glandulartrichomes, dorsiventral mesophyll, calcium oxalate druses and sclereids.

Ontogeny and Structure of the Pericarp of Schinus terebinthifolius Raddi (Anacardiaceae

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Sandra Maria Carmello-Guerreiro

2002-03-01

Full Text Available The fruit of Schinus terebinthifolius Raddi is a globose red drupe with friable exocarp when ripe and composed of two lignified layers: the epidermis and hypodermis. The mesocarp is parenchymatous with large secretory ducts associated with vascular bundles. In the mesocarp two regions are observed: an outer region composed of only parenchymatous cells and an inner region, bounded by one or more layers of druse-like crystals of calcium oxalate, composed of parenchymatous cells, secretory ducts and vascular bundles. The mesocarp detaches itself from the exocarp due to degeneration of the cellular layers in contact with the hypodermis. The lignified endocarp is composed of four layers: the outermost layer of polyhedral cells with prismatic crystals of calcium oxalate, and the three innermost layers of sclereids in palisade.O fruto de Schinus terebinthifolius Raddi é uma drupa vermelha, globosa, com exocarpo friável quando maduro e composto de duas camadas lignificadas: a epiderme e a hipoderme. O mesocarpo é parenquimático com grandes canais secretores associados aos feixes vasculares. No mesocarpo distinguem-se duas regiões uma externa composta apenas de células parenquimáticas e uma interna, delimitada por uma ou mais camadas de células contendo cristais de oxalato de cálcio do tipo drusa, composta de células parenquimáticas, canais secretores e feixes vasculares. O mesocarpo desprende-se do exocarpo devido à degeneração das camadas celulares em contato com a hipoderme. O endocarpo é lignificado e composto de quatro camadas: uma mais externa de células poliédricas com cristais prismáticos de oxalato de cálcio e três mais internas de esclereides em paliçada.

Cretaceous origin of dogwoods: an anatomically preserved Cornus (Cornaceae fruit from the Campanian of Vancouver Island

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Brian A. Atkinson

2016-12-01

Full Text Available Background Cornaceae consists of 58 species, all within the genus Cornus. The Cenozoic record of Cornus is extensive and well documented. Molecular divergence-time studies suggest that crown-group Cornus may have originated by the Late Cretaceous. However, there has been no formal report of Cornus from Cretaceous deposits. Here, we characterize a permineralized fossil fruit assignable to Cornus subg. Cornus from the Upper Cretaceous (Campanian Shelter Point locality of Vancouver Island, British Columbia, Canada. Methods Serial sections of the specimen were made using the cellulose acetate peel technique. Peels were mounted onto microscope slides and studied by light microscopy. Results The fossil fruit consists of a tri-locular woody endocarp with dorsal germination valves. The locules are sub-triangular to ellipsoidal in transverse section and are separated by thin septa. Endocarp tissue consists of elongated and isodiametric sclereids and secretory cavities. Internal vascular tissue was not observed, but is interpreted to have been located along the outer periphery of the septa for some length, common in many cornalean taxa. There is one seed in each locule, one of which was found to have endosperm and a dicotyledonous embryo. Discussion Woody endocarps with germination valves, without central vascular bundles, and with one seed per locule are characteristic of several families within the order Cornales. The interpreted vascular pattern and presence of secretory cavities indicates that the fossil fruit is assignable to Cornus subg. Cornus. Comparative analysis suggests that the fossil is most similar to Cornus piggae, a species described from the Paleocene of North Dakota. This fossil is the first evidence of crown-group Cornaceae from the Cretaceous and sheds light on both the plesiomorphic fruit characters and the timing of the initial diversification of the family and basal asterid lineage, Cornales.

Evolution of wood anatomical characters in Nepenthes and close relatives of Caryophyllales.

Science.gov (United States)

Schwallier, Rachel; Gravendeel, Barbara; de Boer, Hugo; Nylinder, Stephan; van Heuven, Bertie Joan; Sieder, Anton; Sumail, Sukaibin; van Vugt, Rogier; Lens, Frederic

2017-05-01

Nepenthes attracts wide attention with its spectacularly shaped carnivorous pitchers, cultural value and horticultural curiosity. Despite the plant's iconic fascination, surprisingly little anatomical detail is known about the genus beyond its modified leaf tip traps. Here, the wood anatomical diversity of Nepenthes is explored. This diversity is further assessed with a phylogenetic framework to investigate whether the wood characters within the genus are relevant from an evolutionary or ecological perspective, or rather depend on differences in developmental stages, growth habits, substrates or precipitation. Observations were performed using light microscopy and scanning electron microscopy. Ancestral states of selected wood and pith characters were reconstructed using an existing molecular phylogeny for Nepenthes and a broader Caryophyllales framework. Pairwise comparisons were assessed for possible relationships between wood anatomy and developmental stages, growth habits, substrates and ecology. Wood anatomy of Nepenthes is diffuse porous, with mainly solitary vessels showing simple, bordered perforation plates and alternate intervessel pits, fibres with distinctly bordered pits (occasionally septate), apotracheal axial parenchyma and co-occurring uni- and multiseriate rays often including silica bodies. Precipitation and growth habit (stem length) are linked with vessel density and multiseriate ray height, while soil type correlates with vessel diameter, vessel element length and maximum ray width. For Caryophyllales as a whole, silica grains, successive cambia and bordered perforation plates are the result of convergent evolution. Peculiar helical sculpturing patterns within various cell types occur uniquely within the insectivorous clade of non-core Caryophyllales. The wood anatomical variation in Nepenthes displays variation for some characters dependent on soil type, precipitation and stem length, but is largely conservative. The helical-banded fibre-sclereids

Estudo anátomo-morfológico de dicotiledôneas das dunas de Salvador - Bahia: Borreria cymosa Cham. et Schl. e Chiococca brachiata R. et P. (Rubiaceae Morpho-anatomic studies of dicotiledons from Salvador - Bahia dunes: Borreria cymosa Chamo et Schl. and Chiococca brachiata R. et P. (Rubiaceae

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Elzeni Diladelfo de Gusmão

1992-07-01

Full Text Available Prosseguindo as pesquisas sobre a vegetação das Dunas do Abaeté, Salvador, Bahia, apresentam-se as Rubiaceae: Borreria cymosa e Chiococca brachiata. Cortes histológicos à mão livre, com lâminas de barbear, seguindo-se as técnicas de rotina. Estudaram-se as epidermes, mesofilo, nervura central, bordo e pecíolo. Contaram-se os estômatos por área foliar. Folhas dorsiventrais e hipoestomáticas, glabras, cutícula adaxial espessa e brilhante. Numerosas gotas lipídicas, esclereídeos no córtex do pecíolo e nervura central. Borreria: tem epiderme abaxial com paredes fortemente sinuosas e estrias epicuticulares; células incolores, subjacentes à epiderme adaxial; mesofilo com drusas e ráfides de oxolato de cálcio, bainhas de células volumosas envolvendo todos os feixes. Chiococca: epiderme de paredes curvas, cutícula formando "flanges" ao nível da nervura mediana, bordo e pecíolo. Pequenas células cheias de cloroplastos envolvem feixes menores. Clorênquima denso. Conclui-se que as plantas apresentam caracteres de adaptação ao meio xérico. As características anatômicas tanto quanto ao morfológicas individualizam os taxons.Following studies of the vegetation from the dunes of Abaeté, Salvador, Bahia, the Rubiaceae Borreria cymosa and Chiococca brachiata are described. Free hand histological were made with razor blades, following routine procedures. The epidermis, mesophyll, central nerve, margin and petiole were studied. Stomata per area of leaf were counted. Dorsiventral and hypoestomatic leaves, glabrous, adaxial cuticle heavy anda brillant. Numerous lipid droplets, sclereids in cortex of petiole and central nerve. Borreria: has abaxial epidermis with strongly sinuos walls and striated; cells colorless, subjacent to adaxial epidermis; mesophyll with druses and raphides of calcium oxalate, sheaths of volumous cells wrapping all the bundles. Chiococca: epiderm with curved walls, cuticle forming "flanges" at the level of the

Anatomia foliar como subsídio à taxonomia de Hippocrateoideae (Celastraceae no Sudeste do Brasil Leaf anatomy as taxonomic tool for Hippocrateoideae (Celastraceae in the Southeast of Brazil

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Sandra Maria Alvarenga Gomes

2005-12-01

Full Text Available A anatomia foliar de treze espécies pertencentes a nove gêneros da subfamília Hippocrateoideae (Celastraceae foi estudada visando a seleção de caracteres anatômicos para subsidiar a taxonomia dos gêneros e espécies. As espécies estudadas foram: Anthodon decussatum Ruiz & Pav., Cheiloclinium cognatum (Miers A.C. Sm., Cheiloclinium serratum (Cambess. A.C. Sm., Cuervea crenulata Mennega, Elachyptera micrantha (Cambess. A.C. Sm., Hippocratea volubilis L., Peritassa flaviflora A.C. Sm., Peritassa mexiae A.C.Sm., Pristimera nervosa (Miers A.C. Sm., Salacia crassifolia (Mart. ex Schult. G. Don, Tontelea fluminensis (Peyr. A.C. Sm., Tontelea leptophylla A.C. Sm. e Tontelea miersii (Peyr. A.C. Sm. Os caracteres anatômicos selecionados como diagnósticos para a taxonomia dos diferentes gêneros e espécies são: o tipo de esclereíde presente no pecíolo ou na lâmina foliar, o tipo de estômato, a conformação do sistema vascular do pecíolo, a sinuosidade das paredes anticlinais das células epidérmicas, a presença de hipoderme, a ocorrência de laticíferos, dentre outros.Leaf anatomy of thirteen species belonging to nine genera of the subfamily Hippocrateoideae (Celastraceae was studied, in order to select anatomical characters to help the taxonomy at genera and species levels. The species studied were: Anthodon decussatum Ruiz & Pav., Cheiloclinium cognatum (Miers A.C. Sm., Cheiloclinium serratum (Cambess. A.C. Sm., Cuervea crenulata Mennega, Elachyptera micrantha (Cambess. A.C. Sm., Hippocratea volubilis L., Peritassa flaviflora A.C. Sm., Peritassa mexiae A.C. Sm., Pristimera nervosa (Miers A.C. Sm., Salacia crassifolia (Mart. ex Schult. G. Don, Tontelea fluminensis (Peyr. A.C. Sm., Tontelea leptophylla A.C. Sm. and Tontelea miersii (Peyr. A.C. Sm. The selected anatomical characters that can be used as diagnostic for the taxonomy of the distinct genera and species are: the type of sclereids in petiole or leaf blade, stomata type, the

Anatomía de seis especies de helechos del género Dryopteris (Dryopteridaceae de México

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Victoria Hernández

2006-12-01

Full Text Available Se estudió la anatomía del rizoma y hoja de especies mexicanas de Dryopteris Adans. y se comparó con la información disponible para Dryopteridaceae y otras familias de helechos en busca de caracteres anatómicos con valor diagnóstico. La anatomía de rizoma, pecíolo y lámina es similar en las especies del complejo Dryopteris patula. Las células con pared engrosada, no lignificada y en forma de casquete o de "U" presentes alrededor de las meristelas corresponden a colénquima, a diferencia de lo informado para otras familias de helechos. Dryopteris wallichiana (Spreng. Hyl. se distingue anatómicamente de las otras especies estudiadas por presentar un mayor número de capas de esclerénquima y de meristelas en el pecíolo, además de carecer de nidos de esclereidas en el rizoma. Dryopteris rossii y D. maxonii se caracterizan por la presencia de cristales en la periferia de los nidos en el rizoma. Las glándulas en la lámina están ausentes en D. maxonii y D. wallichianaAnatomy of six species of Dryopteris ferns (Dryopteridaceae from Mexico. Rhizome and foliar anatomy of the Mexican Dryopteris Adans. species were studied and compared with other Dryopteridaceae and other fern families to identify anatomical features with diagnostic value. The anatomy of rhizome, stipe, and blade is similar in species of the Dryopteris patula complex. The cells with un-lignified, thickened wall, with cap or U-shape around the meristeles belong to the collenchyma, in contrast with other fern families. Dryopteris wallichiana (Spreng. Hyl. is anatomically distinguished from the other studied species by having more layers of sclerenchyma and meristeles on the stipe, and by the lack of sclereid nests on the rhizome. Dryopteris rossii C. Chr. and D. maxonii Underw. & C. Chr. are characterized by the presence of crystals on the periphery of rhizome nests. D. maxonni and D. wallichiana lack blade glands. Rev. Biol. Trop. 54 (4: 1157-1169. Epub 2006 Dec. 15