Kirichkova, A. I.; Esenina, A. V.
The collection of fossil plants sampled by geologists from VNIGRI at the end of the 20th century from Triassic continental sections drilled by many wells and cropping out in several natural localities and stored at the Museum of Petroleum Geology and Paleontology of the same institute was critically revised. The use of the epidermal method for the study of plant remains with consideration of recent publications dedicated to continental sections of Central Europe made it possible to substantially broaden the taxonomic composition of the Triassic flora and first specify the composition of its pteridosperm representatives. Unlike the Triassic floras of Western Europe, the pteridosperms the Pechora region appeared to be relatively diverse. They number 37 species of 11 genera, which are confined to the upper part of the Triassic sequence: Anguran and Naryan-Mar formations and their analogs. The Middle Triassic, mainly, Ladinian, age of these formations is reliably substantiated both by paleontological (vertebrate and palynological) data and by results of the comparative analysis of the Anguran-Naryan-Mar taphofloras and coeval European type floras dated back to the Anisian-Ladinian by marine faunal remains. The stratigraphic significance of pteridospermous plant remains becomes undoubted for continental sections of the Timan-Pechora basin, while the genera Scytophyllum, Kalantarium, and Kirjamkenia may be considered with respect to their diversity and abundance as representing orthostratigraphic taxa.
Comunidad ectomicorrícica en una cronosecuencia de Pinus radiata (Pinophyta: Pinaceae de la zona de transición climática mediterráneo-templada de Chile central The ectomycorrhizal community in a chronosequence of Pinus radiata (Pinophyta: Pinaceae of the transitional Mediterranean-temperate climatic zone of central Chile
YUSSI M PALACIOS
Full Text Available En ecosistemas naturales y plantaciones, las coníferas establecen asociaciones mutualistas con una comunidad diversa de hongos micorrícicos. El estudio de este tema en Sudamérica es aún incipiente, y no existen antecedentes sobre la dinámica temporal de esta comunidad, y menos de sus potenciales causas, a pesar de su importancia para un país forestal como Chile. En el presente trabajo se evaluó la dinámica de la comunidad ectomicorrícica, identificando y cuantificando los hongos formadores de esta asociación en raíces finas de Pinus radiata en plantaciones de 3, 10 y 20 años. Los resultados confirman que la comunidad ectomicorrícica de P. radiata cambia con la edad de los árboles, la cual difiere más bien en el patrón de dominancia que en la riqueza de especies, separándose un primer grupo de árboles de 3 y 10 años de un segundo grupo de 20 años. Un total de once morfotipos de micorrizas fueron diferenciados. Cuatro de ellos, identificados como Hebeloma crustuliniforme, Inocybe sp., Russula sardonia y Pinirhiza spinulosa, fueron los más abundantes (77, 29, 78 y 8 % respectivamente, mientras las otras se encontraron colonizando menos de 100 puntas de raíz (In natural forest ecosystems and plantations, most trees live in mutualistic association with mycorrhizal fungi. Studies of this association in South America are still scarce, especially when referring to the causes of temporal dynamics of this symbiotic community, despite its importance in countries with a thriving forestry industry like Chile. This study evaluates the dynamics of the ectomycorrhizal community of Pinus radiata stands of 3, 10 and 20 years of age, identifying and quantifying the most common fungal colonizers of fine roots in each age class. The results confirm that the mycobiont community changes with host tree age but that age classes differ in dominance patterns rather than in species richness, with the three- and ten-year-old tree cohorts forming a group separate from the 20-year-old trees. A total of eleven ectomycorrhizal root morphotypes could be distinguished. Four of them which were identified as Hebeloma crustuliniforme, Inocybe sp., Russula sardonia and Pinirhiza spinulosa, were the most abundant (77, 29, 78 and 8 % respectively and were found in more than one root sample whereas the remaining morphotypes accounted for less than 100 (< 7 % root tips and showed a patchy distribution. Inocybe sp. was only found on root tips of three-year-old trees, characterizing as an early-stage mycobiont. H! crustuliniforme appeared as a multi-stage colonizer in all three age classes but was clearly dominant on roots of three- and ten-year-old trees, whereas R! sardonia was mainly found on roots of 20-year-old trees, classifying as a late-stage species together with the unidentified morphotype Pinirhiza spinulosa which is reported for the first time from Chile. Our results suggest that the observed changes in the ectomycorrhizal community are not induced by the site per se, but are rather an effect of the interaction between the trees and their environment.
Full Text Available An integral palaeobotanical study (macro- and microflora has been done of the Salanca ravine outcrop. This place is located in the región of la Cerdaña (Lérida province, Spain, which constitutes an Upper Miocene lacustrine basin from Eastern Pyrenees. The sediments of the Salanca ravine outcrop consist of diatomites and grey mudstones. They have been interpreted as being deposited in distal lacustrine zones. In a palynological study, 79 taxa have been identified. They belong to the divisions Pteridophyta, Pinophyta and Magnoliophyta. The recorded assemblages allow us to reconstruct the vegetation of la Cerdaña during the Vallesian, though the problem of overrepresented taxa exists. The macrofloristic study has revealed the presence of 36 taxa through foliar remanís and winged seeds. The recorded assemblage presents plant remains of the divisions Pinophyta and Magnoliophyta. The best represented remains are leaves of dicotyledonous angiosperms because of their wind transport. The high percentage of angiosperm foliar remains in the sediments of the Salanca ravine outcrop revealed calm water conditions in the neogene lake. The palaeoclimatology deduced from the palynological study and the physiognomic study of macroflora indicates that températe conditions existed in which mixed mesophitíc forest developed where the families Pinaceae, Betulaceae and Fagaceae dominated.Se realiza un estudio paleobotánico (macro- y microflora del afloramiento del barranco de Salanca (comarca de la Cerdaña, Pirineos orientales, Lérida, España. En esta zona durante el Mioceno Superior se desarrolló una cuenca lacustre. Los materiales del barranco de Salanca son fundamentalmente diatomitas y "mudstones" de color gris, que se depositaron en zonas lacustres distales. Tras el estudio palinológico, se han identificado 79 táxones pertenecientes a las divisiones Pteridophyta, Pinophyta y Magnoliophyta. Las asociaciones registradas nos permiten reconstruir la
Thompson, R.L. [Berea College, KY (United States); Wade, G.L. [USDA Forest Service, Burlington, VT (United States); Straw, R.A. [Univ. of Tennessee Plateau Experiment Station, Crossville, TN (United States)
A descriptive study of the naturally invading and planted flora was conducted during 1984-1985 on a 14- and 21-year-old contour surface mine the 14.2 ha Log Mountain Demonstration Area (LMDA), in Bell County, Kentucky. Six habitats are designated from areas created from coal mining; the 1963 bench, 1970 bench, bench highwalls, mine outslopes, mine seeps, and coal haul-telephone microwave tower road. Twenty-four of 25 woody and herbaceous species (11 indigenous, 13 non-indigenous) have persisted from plantings by personnel of the Northeastern Forest Experiment Station, USDA Forest Service. We recommend 11 native and exotic woody and herbaceous species for planting on coal surface-mined areas. An annotated list of vascular plants comprises 360 taxa (286 indigenous, 74 non-indigenous) in 224 genera from 82 families. Taxa consist of 1 Lycopodiophyta, 1 Equisetophyta, 8 Polypodiophyta, 7 Pinophyta, and 343 Magnoliophyta. The most species-rich families are the Asteraceae (64), Poaceae (39), Fabaceae (20), Cyperaceae (16), Rosaceae (13), and Lamiaceae (11). A total of 155 Bell County distribution records were documented. Three threatened Kentucky species (Gentiana decora, Liparis loeselii, Silene ovata) were present in refugial habitats created by surface mining. The high species richness has resulted from native and naturalized invading species from the environs, native and exotic planted species, and species from the remnant seed bank. Forest vegetation is a complex mosaic of natural and semi-natural plant communities on the unplanted and planted areas of LMDA.
Full Text Available The botanical composition of the European roe deer diet in the radioactively contaminated forest ecosystems of Zhytomirske Polesie of the Ukraine was investigated. Deer were caught monthly over a two–year period on three plots in forest habitats typical for Zhytomirske Polesie (fresh and moist mixed coniferous forests and mixed broadleaved forests. An analysis of the stomach contents of hunted deer showed that they consumed leafy as well as leafless stems, grasses, fruits and mushrooms depending on the season and availability of forest plants. Each season was characterized by one major dietary component. In the spring, the main component of the deer diet was the stems of woody plants. 44 species of vascular plants (3% of the natural flora of the region were identified in the roe deer diet including 41 species of Magnoliophyta, of which 34 species of Magnoliopsida and 7 species of Liliopsida, 2 species of Polipodiophyta and one species of Pinophyta. Species such as aspen (Populus tremula, oak (Quercus robur, blackberry (Rubus nessensis and bilberry (Vaccinium myrtillus were consumed year-round.
Hayes, Michael L; Hanson, Maureen R
C-to-U editing modifies 30-40 distinct nucleotides within higher-plant chloroplast transcripts. Many C targets are located at the same position in homologous genes from different plants; these either could have emerged independently or could share a common origin. The 5' sequence GCCGUU, required for editing of C214 in tobacco psbE in vitro, is one of the few identified editing cis-elements. We investigated psbE sequences from many plant species to determine in what lineage(s) editing of psbE C214 emerged and whether the cis-element identified in tobacco is conserved in plants with a C214. The GCCGUU sequence is present at a high frequency in plants that carry a C214 in psbE. However, Sciadopitys verticillata (Pinophyta) edits C214 despite the presence of nucleotide differences compared to the conserved cis-element. The C214 site in psbE genes is represented in members of four branches of spermatophytes but not in gnetophytes, resulting in the parsimonious prediction that editing of psbE C214 was present in the ancestor of spermatophytes. Extracts from chloroplasts from a species that has a difference in the motif and lacks the C target are incapable of editing tobacco psbE C214 substrates, implying that the critical trans-acting protein factors were not retained without a C target. Because noncoding sequences are less constrained than coding regions, we analyzed sequences 5' to two C editing targets located within coding regions to search for possible editing-related conserved elements. Putative editing cis-elements were uncovered in the 5' UTRs near editing sites psbL C2 and ndhD C2.
L. G. Velcheva
Full Text Available It is realized the dendroflora analysis of the scientific and academic arboretum of Melitopol State Pedagogical University named by Bogdan Khmelnitsky and on the basis is treated the recommendations of the range formation of woody plants for Melitopol landscaping. In a stable and continuity culture is 78 species of gymnosperm (Pinophyta and angiosperm (Magnoliophyta departments, which are belonging to 53 genuses from 29 kinds. Leading position in the denroflora arboretum structure occupies pink kind (Rosaceae, which consists of 14 species (18 %. Second place takes up to the olives kind (Oleaceae - 8 species (10, 3%. In third place is willow kind (Salicaceae - 7 species (9 %. Fourth and fifth places in the spectrum of leading families is occupied by kinds representatives of maple (Aceraceae and honeysuckle (Caprifoliaceae - 5 species (6.4%. Dendroflora analysis at the genus level allows us to conclude that the leading genera are poplar (Populus L. and maple (Acer L. - 5 species. Among the 78 studied species, 20 - is the local native flora species, 20 species introduced from North America, from which 5 species belong to the gymnosperm department and 15 - are separated angiosperms. Else 10 species is origined from Asia, 8 species - from China, 4 species is introduced from the Mediterranean, 2 - from Japan. At one species represented by immigrants from Iran, Greece, the Balkans and the Middle East. A large group of plants introduced from the Caucasus. The majority of occurring tree species are light-requiring, undemanding to the soil, drought tolerant. The arboretum dendroflora analysis is shown that two species are protected - evergreen boxwood (Buxus sempervirens L., fruit yew (Taxus baccata L. and three relic plants – fruit yew (Taxus baccata L., japanian Kerry (Kerria japonica L., ginkgo biloba (Ginkgo biloba L.. It is listed the recommended range of woody plants for landscaping Melitopol, which includes 13 species. Key words: green
Arnold, A. Elizabeth
Background Fungal endophytes inhabit symptomless, living tissues of all major plant lineages to form one of earth’s most prevalent groups of symbionts. Many reproduce from senesced and/or decomposing leaves and can produce extracellular leaf-degrading enzymes, blurring the line between symbiotrophy and saprotrophy. To better understand the endophyte–saprotroph continuum we compared fungal communities and functional traits of focal strains isolated from living leaves to those isolated from leaves after senescence and decomposition, with a focus on foliage of woody plants in five biogeographic provinces ranging from tundra to subtropical scrub forest. Methods We cultured fungi from the interior of surface-sterilized leaves that were living at the time of sampling (i.e., endophytes), leaves that were dead and were retained in plant canopies (dead leaf fungi, DLF), and fallen leaves (leaf litter fungi, LLF) from 3–4 species of woody plants in each of five sites in North America. Our sampling encompassed 18 plant species representing two families of Pinophyta and five families of Angiospermae. Diversity and composition of fungal communities within and among leaf life stages, hosts, and sites were compared using ITS-partial LSU rDNA data. We evaluated substrate use and enzyme activity by a subset of fungi isolated only from living tissues vs. fungi isolated only from non-living leaves. Results Across the diverse biomes and plant taxa surveyed here, culturable fungi from living leaves were isolated less frequently and were less diverse than those isolated from non-living leaves. Fungal communities in living leaves also differed detectably in composition from communities in dead leaves and leaf litter within focal sites and host taxa, regardless of differential weighting of rare and abundant fungi. All focal isolates grew on cellulose, lignin, and pectin as sole carbon sources, but none displayed ligninolytic or pectinolytic activity in vitro. Cellulolytic activity