Morphology of stomata of Pinaceae and Cupressaceae from northwestern China
by Wan H., Shen J., Tang L., Li C. (2010)
by Wan H., Shen J., Tang L., Li C. (2010)
by Hamidipour A., Radjabian T., Charlet D. A., Zarrei M. (2011)
Assiyeh Hamidipour, Tayebeh Radjabian, David A. Charlet, Mehdi Zarrei,
in Wulfenia 18: 95 –111 –
Anatomical and morphological investigations of seven species of Iranian representatives of gymnosperms belonging to Taxaceae and Cupressaceae are performed in this study.
Transverse sections of leaves (needle-like or scales) were studied with a light microscope. Great anatomical variation exists between and within Taxaceae and Cupressaceae. Both families are easily distinguished from each other by anatomical characters.
All genera and species in Cupressaceae are also distinguishable. Fiber and resin ducts are present only in Cupressaceae and not in Taxaceae. In Cupressus sempervirens and Juniperus foetidissima, stomata are present only in the upper epidermis of scale-like leaves.
Stomata are present in lateral faces of needle-like leaves in Juniperus excelsa, J. sabina, J. communis and J. oblonga. In these species, stomata are present only in the abaxial epidermis where there are no fibers underneath the epidermis, a characteristic similar to that in Taxus baccata.
Juniperus communis and J. oblonga have stomata that are distributed uniformly in the lower epidermis, except under the midrib of J. oblonga, which is covered with fibers instead of stomata.
by Pisaric M. F. J., Szeicz J. M., Karst T., Smol J. P. (2000)
Michael F.J. Pisaric, Julian M. Szeicz, Tammy Karst, John P. Smol,
M.F.J. Pisaric1 and J.M. Szeicz.2 – Department of Geography, Queen’s University, Kingston, ON K7L 3N6, Canada.
T. Karst and J.P. Smol. – Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen’s University, Kingston, ON K7L 3N6, Canada.
in Can. J. Bot. 78: 1180–1186 –
We compare fossil pollen and stomate assemblages in 29 lake sediment surface samples from mountainous regions in northwestern Canada to characterize the relationship between modern vegetation, and pollen and stomate deposition.
Modern pollen spectra were dominated by arboreal taxa originating from lower elevation sites. Pinus pollen frequently reached 30% of the pollen sum, regardless of elevation. Alpine-tundra vegetation has lower pollen abundance, even in the alpine-tundra zone, where it dominates the sparse vegetation cover.
Fossil stomates were observed in all but one site where trees currently exist in the vicinity of the lake, while no stomates were found in the sediments from alpine-tundra sites.
The highest concentration of stomates occurred in lake sediments from closed-canopy forested areas. Our data suggest that different boreal forest types may be differentiated based on pollen assemblages and that the presence of stomates clearly distinguishes vegetation zones dominated by arboreal vegetation from alpine-tundra zones where trees are not present.
Les auteurs ont comparé des ensembles de pollens et de stomates fossiles dans 29 échantillons de sédiments lacustres de surface, provenant de régions montagneuses du nord-ouest canadien, afin de caractériser la relation qui existe entre la végétation contemporaine et les dépôts de pollens et de stomates. Les spectres de pollens contemporains sont dominés par des taxons arborescents provenant de sites de faible élévation. La fréquence du pollen de Pinus at- teint 30 % de la somme des pollens, indépendamment de l’élévation. La végétation de toundra alpine présente une abondance pollinique moindre, même dans la zone de toundra alpine, où elle-ci domine le couvert végétal épars. On observe des stomates fossiles dans tous les sites, sauf un, où il existe présentement des arbres au voisinage du lac, alors qu’on ne trouve pas de stomates dans les sédiments des sites de végétation de toundra alpine. Les plus fortes den- sités de stomates se retrouvent dans les sédiments de lacs voisins de peuplements forestiers à canopée fermée. Les don- nées suggèrent que différents types de forêts boréales peuvent être différenciés en se basant sur les ensembles polliniques, et que la présence de stomates distingue clairement les zones de végétation dominées par de la végétation arborée, des autres zones de toundra alpine où il n’y pas d’arbres.
by Bender O., Rudnik T. I. (2008)
Institute for Monitoring of Climatic and Ecological Systems SP RAS, Russia, 634055, Tomsk, pr. Academicheskij10/3.
in Annals of Forest Research 51(1): 165-168 –
Siberian stone pine (Pinus sibirica Du Tour) is one of the most common trees in Siberia. Its natural range is from the Ural Mountains to the Aldan river and from the Arctic Circle to northern Mongolia. The climate in natural Siberian stone pine sites influences the whole plant organism, particularly its needle structure, and the response to this occurs at specific morphological and anatomical levels. The genotypical and environmental effects on needle structure in different Siberian stone pine ecotypes are very little known.
One effective way to examine and to separate genotypical effects from environmental ones is by using a common garden experiment. The purpose is to analyze morphological and anatomical needle variability in Siberian stone pine marginal populations that have been grown in provenance plantations in southern West Siberia, Russia.
The needle samples were collected in the provenance plantation located 30 km south of Tomsk (the southeastern West Siberian Plain, southern limit of the taiga zone, optimum site conditions for Siberian stone pine). We investigated the grafts of mother trees taken from natural sites. Four ecotypes were selected for the study. Three ecotypes originated from northern (Urengoy), western (Neviyansk), and eastern (Severobaikalsk) marginal populations. The fourth, the Tomsk ecotype, was a local control. The local Tomsk ecotype grows on a site where natural conditions are worse due to reduction of mean annual temperature and increase of the humid factor northward, humidity reduction eastward and its rise westward. Variability of 10 needle morphological and anatomical characteristics was studied.
The northern ecotype had smaller needle length (28%), leaf cross-section area (21%), mesophyll area (29%), mesophyll cell size (27%), and conducting bundle area (16%) but the number of stomata per unit leaf area increased by 16% over the local Tomsk ecotype. The resin canal area, epidermal and hypodermal cell thickness, and stomata size were equal to both the northern and local ecotypes.
The leaf cross-section and mesophyll area in the western ecotypes decreased by 20% and 23%, respectively, but stomata size increased by 12%. The needle length, mesophyll
cell size, conducting bundle area, resin canal area, the number of stomata per unit leaf area, and epidermal and hypodermal cell thickness did not differ significantly from the same characteristics in the Tomsk ecotype.
The leaf cross-section area, mesophyll area, and mesophyll cell size in the eastern ecotype decreased by 22%, 37% and 20% respectively, as compared with the local ecotype. All other studied needle characteristics did not differ from the local ecotype. The common morphological and anatomical parameters did not change from south to north and from west to east (resin canal area and hypodermal cell thickness) and parameters varied in each ecotype. For example, needle length, conducting bundle area, and the number of stomata per unit leaf area changed along latitude but did not change
Conversely, stomata size and epidermal cell thickness changed along longitude but did not change along latitude. Thus the morphological and anatomical characteristics were specific for each ecotype. The parameter variability of the needle structure is hypothesized to relate to graft geographical provenance that depends on genotype and adaptation properties of mother trees.
Photo credi: Google
View the 2,000 Year Old Welwitschia mirabilis plants
Takeda H. (1913b)
in Ann. of Bot. 27: 347-375 – https://doi.org/10.1093/oxfordjournals.aob.a089462 –
Photo credit: Google
Podocarpus macrophylla – This is the foliage and blue female cones of the yew pine Podocarpus macrophyllus ‘Maki’. The foliage of the species is shown in the inset.
by Stockey R. A., Frevel B. J., Woltz P. (1998)
Ruth A. Stockey, Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
Brenda J. Frevel, Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
Philippe Woltz, Laboratoire de Morphogenèse Végétale, I.M.E.P. CNRS‐URA 1152, Université d’Aix, Marseille III, Centre St. Jérôme, France
in Int. J. Plant Sci. 159: 923-940 – DOI: 10.1086/297613
Cuticle micromorphology of leaves from seven species and three varieties of the conifer genus Podocarpus subgenus Podocarpus section Scytopodium from South Africa and Madagascar was studied with scanning electron microscopy.
External and internal features of abaxial and adaxial cuticles are characterized for all taxa and are compared with other known Podocarpus species. External cuticles exhibit Florin rings and stomatal plugs with underlying epidermal cell outlines usually visible.
Leaves are hypostomatic and stomata occur in discontinuous but fairly regular rows in most species. Stomata are oriented parallel to the long axis of the leaf and usually lack polar subsidiary cells. From two to six subsidiary cells occur, with two or three being the most common.
Internal cuticle on subsidiary cell surfaces is granular to rugose, usually with a deep groove corresponding to the external Florin ring. Cuticle on guard cell surfaces is granular or rugose to pitted, and prominent polar extensions are present in all species.
Epidermal cell outlines are undulating and cuticle on epidermal cell surfaces is granular to rugose and pitted.
The most useful characters to distinguish species of this section are the micromorphology of cuticle on the guard cell and subsidiary cell surfaces, epidermal cell shapes, and sometimes the length of polar extensions.
Photo credit: Google
by Stockey R. A., Ko H. (1990)
Ruth A. Stockey,
in Bot. Gazette 151: 138-149 – (ISSN: 0006-8071) – DOI : 10.1086/337813
Cuticle micromorphology of herbarium and of preserved leaves of four species of the genus Dacrydium was studied with scanning electron microscopy.
Dacrydium araucarioides, D. balansae, D. guillauminii, and D. lycopodioides from New Caledonia are all representatives of the tropical subgroup of the genus.
External and internal features of abaxial and adaxial cuticles are characterized for all taxa. External cuticle surfaces of all species lack the Florin rings present in other members of the Podocarpaceae.
Sunken stomata in discontinuous rows characterize all taxa. Subsidiary cell number varies from two to five. Epidermal cell outlines are very sinuous, and cuticle from cell surfaces is smooth to slightly pitted.
Cuticle on guard cell surfaces distinguishes the taxa. Micromorphological features are compared with other previously studied genera in the Podocarpaceae. The New Caledonian species of the genus Dacrydium show a close similarity to each other in micromorphological features of leaf cuticle and are easily distinguishable from other podocarp genera.