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Studied Taxa (studied + taxa)

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Life Sciences	100%

Selected Abstracts

Pollen morphology, leaf surfaces, mycobiota diversity and leaf spots of three species of Zygophyllum growing along Cairo-Suez desert road, Eastern (Arabian) desert in Egypt

FEDDES REPERTORIUM, Issue 1-2 2007
S. M. El Naggar
Three native species of Zygophyllum: Z. coccinum L., Z. decumbens L. and Z. simplex L. (Zygophyllaceae) have been investigated morphologically, palynologically and mycologically. Twenty-two fungal species belonging to 11 genera were collected from leaf surfaces (11 genera and 22 species) and anthers/ pollen grains (7, 13) of Zygophyllum coccinum, Z. decumbens and Z. simplex on Czapek-Dox agar at 25 °C. Fungal diversity of the two microhabitats is basically similar and the most prevalent fungi were Alternaria alternata /A. phragmospora, Cladosporium cladosporioides /C. herbarum and Ulocladium botrytis /U. consortiale. Alternaria alternata, Cladosporium cladosporioides and C. herbarum -leaf spots were rarely recorded in the three studied plant species. Leaf lamina size and sculpture of the studied taxa almost seem to be the most reliable factors of the fungal biodiversity on the studied plant species. On the other hand, reticulate-micro reticulate pollen type is the only pollen type recorded in the present study which reflects that the very narrow range of spectrum of fungal biodiversity between the studied plant species. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Pollenmorphologie, Blattoberfläche, mykobiotische Diversität und Blattflecken von drei Zygophyllum -Arten entlang der Wüstenstraße Kairo,Suez, Östliche (Arabische) Wüste Ägyptens Drei einheimische Zygophyllum -Arten (Z. coccinum, Z. decumbens und Z. simplex (Zygophyllaceae) wurden morphologisch, palynologisch und mykologisch untersucht. 22 Pilzarten aus elf Gattungen wurden von Blattoberflächen gesammelt (11 Gattungen, 22 Arten) und Antheren/Pollenkörner (7, 13) von Zygophyllum coccinum, Z. decumbens und Z. simplex mittels Czapek-Dox agar bei 25 °C untersucht. Die Pilzdiversität beider Mikrohabitate ist basisähnlich und die häufigsten Taxa sind: Alternaria alternata /A. phragmospora, Cladosporium cladosporioides /C. herbarum und Ulocladium botrytis /U. consor- tiale. Blattflecken von Alternaria alternata, Cladosporium cladosporioides und C. herbarum wurden auf den untersuchten Pflanzen selten verzeichnet. Die Größe der Blattlamina und die Skulptur der untersuchten Taxa scheinen die zuverlässigsten (häufigsten) Faktoren für die Pilz-Biodiversität auf den untersuchten Pflanzen zu sein. Andererseits ist der retikulate-microretikulate Pollentyp in vorliegender Studie der einzige Pollentyp, der dieses enge Spektrum der Pilz-Biodiversität zwischen den untersuchten Pflanzen aufzeigt (widerspiegelt). [source]

Fungal biodiversity, pollen morphology and leaf surface of some native species in Egypt

FEDDES REPERTORIUM, Issue 1 2001
S. I. I. Abdel-Hafez
Five native species of the flora of Egypt: Adonis dentata Delile, Ranunculaceae; Papaver dubium L., Papaveraceae; Matthiola longipetala (Vent.) DC., Brassicaceae; Malva parviflora L., Malvaceae; and Erodium laciniatum (Cav.) Willd., Geraniaceae have been investigated morphologically, palynologically and mycologically. The total counts of phyllosphere fungi fluctuated between 223 and 388 colonies/100 leaf segments giving maximum on Malva parviflora followed by Matthiola longipetala, Erodium laciniatum, Papaver dubium and Adonis dentata. The widest spectrum of genera (20) and species (39 and l variety) was recorded on Malva parviflora and the narrowest on Adonis dentata (9, 14). Sixty species and one variety belonging to 27 genera were collected from leaves (24 genera and 56 species and 1 variety) and anthers/pollen (16 genera and 27 species) of the five studied plants with the most frequently species were some members of Alternaria, Cladosporium, Fusarium and Mucor. Members of Aspergillus and Penicillium were prevalent only on leaves of Matthiola longipetala and Malva parviflora, while these members were infrequently recorded on leaf surfaces of Adonis dentata and Papaver dubium. Results revealed that density of hairs on the leaf surface and size of leaf blade, almost seem to be the most reliable factors of the biodiversity of the fungal spores on the studied taxa. On the other hand, reticulate or striate pollen surface had a wider spectrum of fungal biodiversity and higher densities of spores compared with echinate and scabrate surface. Pilz-Biodiversität, Pollen-Morphologie und die Blattoberfläche einiger einheimischer Arten in Ágypten Aus der Flora Ágyptens wurden die fünf einheimischen Arten Adonis dentata Delile, Ranunculaceae; Papaver dubium L., Papaveraceae; Matthiola longipetala (Vent.) DC., Brassicaceae; Malva parviflora L., Malvaceae; und Erodium laciniatum (Cav.) Willd., Geraniaceae morphologisch, palynologisch und mykologisch untersucht. Die Gesamtzahl an phyllosphären Pilzen schwankte zwischen 223 und 388 Kolonien/100 Blattsegementen. Das Maximum lag bei Malva parviflora, gefolgt von Matthiola longipetala, Erodium laciniatum, Papaver dubium und Adonis dentata. Das größte Spektrum an Gattungen (20) und Arten (39 und 1 Varietät) wurde bei Malva parviflora verzeichnet, das Minimum hingegen bei Adonis dentata (9, 14). An den fünf Arten wurden insgesamt 60 Arten und eine Varietät aus 27 Gattungen an Blättern (24 Gattungen, 56 Arten und eine Varietät) und Antheren/Pollen (16 Gattungen, 27 Arten) verzeichnet. Die häufigsten Arten gehörten zu den Gattungen Alternaria, Cladosporium, Fusarium und Mucor. Arten von Aspergillus und Penicillium wurden nur an Blättern von Matthiola longipetala und Malva parviflora nachgewiesen, während sie an den Blattoberflächen von Adonis dentata und Papaver dubium seltener waren. Aus den erzielten Resultaten ergibt sich, dass die Dichte des Haarbesatzes an der Blattoberfläche und die Größe der Blattspreite die entscheidenden Faktoren zur Biodiversität der Pilzsporen an den untersuchten Taxa sind. Anderseits kann man sagen, dass reticulate und striate Pollen im Vergleich zu einer echinaten und skabraten Oberfläche ein größeres Spektrum der Pilz-Biodiversität und eine höhere Sporendichte aufwiesen. [source]

Genetic variation and clonal diversity in four clonal sedges (Carex) along the Arctic coast of Eurasia

MOLECULAR ECOLOGY, Issue 2 2001
Anna Stenström
Abstract We studied the structure of genetic variation (at both ramet- and genet-level) and clonal diversity within and among populations in the four closely related arctic clonal sedges Carex bigelowii, C. ensifolia, C. lugens and C. stans by use of allozyme markers. Compared to other sedges and arctic plants, the studied taxa all had high levels of genetic variation, both within populations and taxa. These taxa contained most of the total gene diversity (HT) within populations and a small part of the diversity among populations (GST ranged 0.05,0.43). Carex bigelowii had genetic variation (HS = 0.173, mean for populations) at a comparable level to other outbreeding arctic plants and to other widespread, rhizomatous and mainly outbreeding Carex species. In contrast, C. ensifolia (HS = 0.335), C. lugens (HS = 0.339) and C. stans (HS = 0.294) had within-population variations that were higher than in most other studied Carex species and for arctic plants in general. Genetic variation was not related to any tested environmental variable, but it was lower in areas deglaciated only 10 000 years bp compared to areas deglaciated 60 000 years bp or not glaciated at all during the Weichselian. All the populations were multiclonal, except for two populations of C. stans that were monoclonal. In contrast to genetic variation, clonal diversity decreased with latitude and did not differ between areas with different times of deglaciation. In accordance with previous studies, C. bigelowii and C. lugens were found to be outbreeding, while C. ensifolia and C. stans had mixed mating systems. [source]

Intercalary Elements, Treefrogs, and the Early Differentiation of a Complex System in the Neobatrachia

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 12 2007
Adriana S. Manzano
Abstract Intercalary elements are additional skeletal structures of digits of many anuran amphibians. Twelve terminal clades in the neobatrachian lineage of frogs have intercalary elements revealing it is a homoplastic character with five to seven gains and two to four losses along a consensus phylogeny of the Neobatrachia. We analyzed anatomical variation of intercalary elements, related structures (distal phalanges, tendons, and muscles), and articulations of digits of 45 anuran species, representing eight suprageneric terminal taxa. The intercalary elements are integrated in a complex system that is probably related to different types of movements, which are produced by a similar set of muscles and tendons with limited variation among the studied taxa. Species in the clades Hyloides and Ranoides show distinctive patterns of morphostructural features in their intercalary elements that are usually wedge-shaped and composed of hyaline cartilage in Ranoides, and biconcave and composed of embryonic cartilage in Hyloides. Features derived from the typical hyloid condition may only be interpreted in some Hylidae (Pseudis and Lysapsus) and Centrolenidae. In Ranoides, the described features of the intercalary elements are found in all taxa examined with the exception of Leptopelis, which have an intercalary element similar to the other Ranoides but formed by connective tissue. Several features are shared by all taxa having intercalary elements: (1) the intercalary elements differ from the phalanges by lacking terminal epiphyses, (2) they are present in hands and feet, and (3) they appear in all digits. This finding suggests that the genetic basis for presence of intercalary elements may be homologous in all these taxa and may have evolved only once early in neobatrachian history. Anat Rec, 2007. © 2007 Wiley-Liss, Inc. [source]

Morphology, Biometry, and Taxonomy of Freshwater and Marine Interstitial Cyphoderia (Cercozoa: Euglyphida)

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 3 2009
MILCHO TODOROV
ABSTRACT. Good taxonomy is essential for ecological, biogeographical, and evolutionary studies of any group of organisms. Therefore, we performed detailed light- and scanning electron microscopy investigations on the shell ultrastructure and biometric analyses of the morphometric variability of five freshwater and marine interstitial testate amoebae of the genus Cyphoderia (C. trochus var. amphoralis, C. ampulla, C. margaritacea var. major, C. compressa, and C. littoralis), isolated from different populations in Bulgaria and Switzerland. Our aims were (1) to clarify the morphological characteristics of these taxa, and (2) to compare the morphology of a given taxon (C. ampulla) among different locations in Bulgaria and Switzerland as a first step towards an assessment of the geographical variation within a supposedly cosmopolitan taxon. Four of the studied taxa are characterized by a well-expressed main-size class and by a small size range of all the characters and can be defined as size-monomorphic species. Based on these results, the following systematic changes are proposed: C. major (Penard, 1891) n. comb. (Syn.: C. margaritacea var. major (Penard, 1891) and C. amphoralis (Wailes & Penard, 1911) n. comb. (Syn.: C. trochus var. amphoralis (Wailes & Penard, 1911)). However, we also show significant morphological variability between the Swiss and Bulgarian populations of C. ampulla, suggesting the possible existence of more than one taxon within this species. Further studies are required to assess (1) if these two morphologically different taxa represent individual species, (2) if so, if more species exist, and if this diversity is due to limited distribution ranges (endemism) or if several closely related taxa occur together in different geographical areas. [source]