Distribution of scalariform and simple perforation plates within the vessel network in secondary xylem of Araliaceae and its implications for wood evolution

2009 ◽  
Vol 278 (1-2) ◽  
pp. 43-51 ◽  
Author(s):  
Alexei A. Oskolski ◽  
Steven Jansen
2007 ◽  
Vol 21 (4) ◽  
pp. 813-822 ◽  
Author(s):  
Patricia Soffiatti ◽  
Veronica Angyalossy

(Anatomy of Brazilian Cereeae (subfamily Cactoideae, Cactaceae): Arrojadoa Britton & Rose, Stephanocereus A. Berger wâBrasilicereus Backeberg). Arrojadoa, Stephanocereus and Brasilicereus are endemic Brazilian Cereeae, occurring along the Espinhaço Range, in the campos rupestres, cerrados and caatingas, from northern Minas Gerais to southern Bahia. The genera are columnar, erect to semi-erect cacti, except for one species, A bahiensis, which is globose. This study describes the anatomy of dermal, fundamental and vascular systems, aiming to find diagnostic characters for the genera and species. Basal portions of stems were sectioned transversely and longitudinally, and stained with Astrablue and Safranin. The species share a uniseriate epidermis, with thick cuticle; well developed collenchymatic hypodermis, containing prismatic crystals; cortex with numerous mucilage cells, druses and vascular bundles; outside cortex as a palisade parenchyma; periderm composed of lignified cork cells alternating with suberized cells; pheloderm consisting of a few layers of thin-walled cells; phloem composed of solitary or multiple of two to three sieve tube elements, companion cells, axial and radial parenchyma; secondary xylem with solitary to multiple vessels, with simple perforation plates and alternate bordered to semi-bordered pits; axial parenchyma scanty vasicentric to incomplete; libriform septate fibres; large rays. Unlignified parenchyma is seen in the secondary xylem, varying from a few cells to bands among axial and radial elements. The following are considered diagnostic characters: the shape of lignified phellem cells, cubic to radially elongate, which individualizes S. leucostele; an underdeveloped hypodermis and the occurrence of sclereids in the cortex are exclusive to Brasilicereus markgrqfii.


2017 ◽  
Vol 4 (1) ◽  
Author(s):  
João Carlos Ferreira de Melo Junior ◽  
Maick William Amorim ◽  
Gustavo Borda De Oliveira ◽  
Celso Voos Vieira

The wood anatomy is able to evidence systematic and ecological aspects associated with the evolution and functionality of the secondary xylem. The present study was carried out using wood of Chiococca alba (Rubiaceae) from cerrado (savannah), to describe its anatomy and to verify if the hydraulic architecture of this species corroborates the theory that postulates the functional tendency that optimizes the transport efficiency associated with safety. The anatomical analysis followed the conventional protocols of wood anatomy. Different indexes of wood hydraulics quantification were calculated, such as solitary vessels index, vessel grouping, conductivity, vessel collapse, theoretical resistance to vessel implosion and mesomorphism. The structural characteristics described for C. alba are in agreement with the general anatomical descriptions for the Rubiaceae family that relate the presence of exclusively solitary vessels and small diameter, simple perforation plates, alternate intervessel pits, apotracheal parenchyma in species with non-septate fibers and narrow and heterogeneous rays. The calculated indexes showed that C. alba is a xerophyte species with great resistance to the collapse of the vessels during the transport of water, little vulnerability to embolism and relative efficiency in the transport when compared to other species of its subfamily (Cinchonoideae) in function of the typical low water availability of the savannah soil.


IAWA Journal ◽  
1997 ◽  
Vol 18 (3) ◽  
pp. 229-245 ◽  
Author(s):  
Vanessa E.T.M. Ashworth ◽  
Gracielza Dos Santos

Secondary xylem characteristics were compared in four species of Phoradendron Nutt. (Viscaceae) native to California. All have extremely short, thick-walled vessel elements with simple perforation plates. They also share high vessel density, radial vessel arrangement, thick-walled fibres, and multiseriate, heterocellular rays. The fibres show considerable intrusive growth. Features of the vessel elements (i.e. vessel dimensions, arrangement, type of wall sculpturing) and calcium oxalate crystals in the ray parenchyma cells are useful diagnostic traits to separate species. Grooved vessel walls are shared by the morphologically similar P. villosum and P. macrophyllum. Differences between these two species may reflect contrasting drought response strategies pursued by respective hosts. Vulnerability and mesomorphy ratios of the wood of P. californicum are higher than those of P. pauciflorum and P. macrophyllum. Phoradendron pauciflorum has the most xeromorphic wood of the four species studied.


IAWA Journal ◽  
2012 ◽  
Vol 33 (2) ◽  
pp. 163-186 ◽  
Author(s):  
Bernard J. De Villiers ◽  
Alexei A. Oskolski ◽  
Patricia M. Tilney ◽  
Ben-Erik Van Wyk

The wood structure of two related African genera, Cussonia Thunb. (15 of 21 species) and the monotypic Seemannaralia R.Vig. (Araliaceae) is examined. The considerable diversity in wood anatomical characters within these taxa is mostly related to environmental factors; taxonomic groupings or phylogenetic relationships seem to be less important. The shortening of vessel elements and fibres, an increase in vessel number per group, a decrease in vessel diameter and a reduction in the number of bars of perforation plates, are associated with the more temperat species. The changes in vessel grouping show a significant correlation with rainfall. The placement of the simple-leaved Cussonia species in the subgenus Protocussonia and the isolated position of C. paniculata Eckl. & Zeyh., the only member of the subgenus Paniculatae, are supported. Many Cussonia species share a very low fibre to vessel element length ratio. Despite the basal position of Seemannaralia relative to Cussonia revealed by molecular data (Plunkett et al. 2004), its wood structure is more specialised in terms of the Baileyan major trends in wood evolution. This discrepancy may be the effect of a long-term adaptation of tropical ancestors of Seemannaralia to drier biomes.


IAWA Journal ◽  
1991 ◽  
Vol 12 (4) ◽  
pp. 389-415 ◽  
Author(s):  
Peter Gasson ◽  
David R. Dobbins

The secondary xylem anatomy of trees and lianas was compared in the family Bignoniaceae. General descriptions of the family and the six woody tribes are provided. Lianas belong to the tribes Bignonieae, Tecomeae and Schlegelieae, and most have ve.ssels of two distinct diameters, many vessels per unit area, large intervascular pits, septate fibres, large heterocellular rays often of two distinct sizes, scanty paratracheal and vasicentric axial parenchyma and anomalous growth. Conversely, trees, which belong to the tribes Coleeae, Crescentieae, Oroxyleae and Tecomeae generally have narrower vessels in one diameter class, fewer vessels per unit area, smaller intervascular pits, non-septate fibres, small homocellular rays, scanty paratracheal, aliform or confluent parenchyma, and none exhibits anomalous growth. The majority of both trees and Hanas possess growth rings, are diffuse-porous, have non-solitary vessels which lack helical thickenings, and few have apotracheal parenchyma or storied structure. All species have alternate intervascular pitting and simple perforation plates.


IAWA Journal ◽  
1987 ◽  
Vol 8 (3) ◽  
pp. 202-212 ◽  
Author(s):  
Pedro L. B. Lisboa ◽  
J. Cesar A. da Silva ◽  
A. A. Loureiro ◽  
Gracielza M. dos A. dos Santos

A morphological study of vessel elements was carried out in species representing the five genera of Myristicaceae present in the Brazilian Amazon region. The results show that perforation plates of the scalariform type predominate in Compsoneura, Iryanthera and Otoba, where as perforation plates of the simple type predominate in Osteophloeum and Virola. The phylogenetic and taxonomie implications of these findings are discussed.


1995 ◽  
Vol 17 (17) ◽  
pp. 87
Author(s):  
José Newton Cardoso Marchiori ◽  
Graciela I. Bolzon de Muñiz

The anatomical features of the secondary xylem of Ephedra tweediana C.A. Meyer are described. They are also furnished photomicrographs as well as quantitative data of its structure. The wood anatomy fits with the described in the literature to other species of the same genus. In the wood of Ephedra tweediana they are found real vessels and very tall rays, up to 8 cells wide. These features are common in the Angiosperm Dicotyledons but absent in the Gymnosperms, with the exception ofthe Chlamydospermae or Gnetales. Ephedra separates itself in this group by the presence of foraminate or "ephedroid" perforation plates. In the xylem anatomy of this south brazilian species, they must be also emphasized the presence of very short tracheids, provided with uniseriate bordered pits and the peculiar "stepped outline" of annual rings.


FLORESTA ◽  
2013 ◽  
Vol 43 (4) ◽  
pp. 643 ◽  
Author(s):  
Anelise Marta Siegloch ◽  
José Newton Cardoso Marchiori ◽  
Sidinei Rodrigues dos Santos

São anatomicamente descritos os xilemas secundários de Euphorbia cotinifolia L., E. pulcherrima Willd. ex Klotzch e E. tirucalli L. As descrições anatômicas seguem IAWA (1989). Para as três espécies, foram confirmados os seguintes detalhes anatômicos mencionados na literatura para família Euphorbiaceae e gênero Euphorbia: poros em múltiplos radiais; placas de perfuração simples; pontoações intervasculares de diâmetro médio; pontoações raio-vasculares alongadas; parênquima axial com 2-4 células por série; raios com 1-3 células de largura; fibras frequentemente gelatinosas; e presença de laticíferos radiais.Palavras-chave: Análise de agrupamento; estudo anatômico; Euphorbiaceae. AbstractComparative study of the secondary xylem of three ornamental Euphorbia species. The wood anatomy of Euphorbia cotinifolia, E. pulcherrima and E. tirucalli, are described. The anatomical descriptions follow IAWA (1989). The following details mentioned in the literature to family Euphorbiaceae and genus Euphorbia were confirmed to the three species: radial multiple pores; simple perforation plates; medium size intervessel pits; elongated vascular-ray pits, axial parenchyma in series with 2-4 cells; rays with 1-3 cells wide; usually gelatinous fibers; and laticifers in rays.Keywords: Cluster analysis; euphorbiaceae; wood Anatomy.


IAWA Journal ◽  
1994 ◽  
Vol 15 (1) ◽  
pp. 51-63 ◽  
Author(s):  
Sheila M. Hayden ◽  
W. John Hayden

Anatomy and development of vascular tissues in the annual stems of Croton glandulosus var. septentrionalis are described. In primary stages of growth the stem possesses a eustele of bicollateral bundles; internal phloem is notably more extensive than the external. In addition to a vascular cambium and secondary xylem that form in the usual fashion, additional cambia add cells to the internal phloem portion of the bicollateral bundles, forming well-marked medullary bundles at the perimeter of the pith. At first, the perimedullary cambial strands produce only internal secondary phloem; later, internal secondary xylem is also formed in some stems. When internal secondary xylem is present, the medullary bundles have an inverted orientation, i.e., phloem innermost (towards centre of pith) and xylem outermost (near protoxylem). Cells of the medullary bundles include sieve tube elements, vessel ekments, and fibres. Normal (external) secondary phloem is weakly developed. Normal secondary xylem contains short vessel elements with simple perforation plates and alternate intervascular pits, libriform fibres, narrow heterocellular rays, and lacks axial parenchyma.


Sign in / Sign up

Export Citation Format

Share Document