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1

Effects of seven pure flavonoids from mosses on germination and growth of Tortula muralis HEDW (Bryophyta) and Raphanus sativus L (Magnoliophyta).  

PubMed

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss Tortula muralis and on seed germination and root growth of Raphanus sativus. Flavonoids caused a decrease in the percentage of spore germination, protonemal development and root growth. In addition they caused morphological alterations, such as forked tips, swollen apices, rounded cells and early formation of brood cells in the protonemata. Data were discussed in relation to the presence of allelochemicals in mosses. PMID:12591270

Basile, Adriana; Sorbo, Sergio; López-Sáez, José Antonio; Castaldo Cobianchi, Rosa

2003-04-01

2

Effects of seven pure flavonoids from mosses on germination and growth of Tortula muralis HEDW. (Bryophyta) and Raphanus sativus L. (Magnoliophyta)  

Microsoft Academic Search

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss

Adriana Basile; Sergio Sorbo; José Antonio López-Sáez; Rosa Castaldo Cobianchi

2003-01-01

3

Biology 5319 -Topics in Botany (Agrostology) -Fall 2007 Instructor: Dr. David E. Lemke  

E-print Network

% Textbooks Flora of North America Editorial Committee. 2003. Flora of North America, vol. 25. Magnoliophyta: Commelinidae: Poaceae, part 2. Oxford University Press, New York. Flora of North America Editorial Committee. 2007. Flora of North America, vol. 24. Magnoliophyta: Commelinidae: Poaceae, part 1. Oxford University

Aspbury, Andrea S. - Department of Biology, Texas State University

4

Potential allelopathic activity of Sideritis italica (Miller) Greuter et Burdet essential oil  

Microsoft Academic Search

Sideritis italica (Miller) Greuter et Burdet is a widespread Mediterranean Lamiacea. Essential oils from S. italica flowerheads and leaves were extracted by hydrodistillation and then tested for their potential allelopathic activity against Raphanus sativus L. (Magnoliophyta) and the moss Tortula muralis (Hedw.) (Bryophyta), two organisms already tested for allelopathy, and against two bryophytes growing in the same environment as S.

A. Basile; R. C. Cobianchi; D. Rigano; F. Senatore; M. Bruno; S. Rosselli; B. Conte; S. Sorbo

2011-01-01

5

Changes due to invasion of Myriophyllum sibiricum in a shallow lake in Åland, SW Finland  

Microsoft Academic Search

Lake Österträsk, a shallow, 25 ha lake in Åland, SW Finland, was invaded by the common watermilfoil, Myriophyllum sibiricum Komarov 1914 (Magnoliophyta: Haloragaceae), in the 1990s. In summer 2006 the dense vegetation, up to 2.5 m tall, richly branching Myriophyllum shoots, caused pH values of about 10 and oxygen supersaturation near the surface. Deeper layers were hypoxic throughout the season.

Tore Lindholm; Eeva Rönnholm; Kerstin Häggqvist

2008-01-01

6

Biodiversity patterns of macrophyte and macroinvertebrate communities in two lagoons of Western Greece.  

NASA Astrophysics Data System (ADS)

Aquatic macrophytes and benthic macroinvertebrates were studied seasonally (Spring, Autumn, Summer) between the years 2009 - 2011 in two coastal lagoons (Kotychi and Prokopos) located in Peloponnese, Greece, in order to investigate spatial and temporal biodiversity trends related to hydrological processes (degree of confinement, nitrates, phosphates, chl-a, total suspended materials, light irradiance, pH, salinity, temperature and dissolved oxygen). Kotychi lagoon presents a better communication with the sea, while Prokopos has a high degree of confinement. Both ecosystems seasonally receive freshwater input from streams. The submerged aquatic macrophytes constituted a major component of the ecosystems studied. In total, 22 taxa of aquatic macrophytes (angiosperms and macroalgae), 16 taxa for Kotychi (2 Rhodophyta, 8 Chlorophyta, 5 Magnoliophyta, 1 Streptophyta) and 14 taxa for Prokopos (1 Rhodophyta, 5 Chlorophyta, 5 Magnoliophyta, 3 Streptophyta) were found. Ruppia cirrhosa, and Potamogeton pectinatus were dominant in both lagoons. Kotychi lagoon was also dominated by Zostera noltii and Prokopos by Zannichellia pallustris ssp. pedicellata, while the biomass of aquatic species peaked during the summer periods, in both lagoons. The total number of macroinvertebrates found in the lagoons was 28 taxa for Kotychi and 19 for Prokopos. Chironomidae were dominant in both lagoons, while Kotychi was also dominated by Lekanesphaera monodi and Monocorophium insidiosum, and Prokopos by Ostracoda and Lekanesphaera monodi. Benthic diversity ranged from 1.33 to 2.57 in Kotychi and from 0.67 to 2.48 in Prokopos. Species richness, diversity, and abundance of benthic macroinvertebrates were strongly related to aquatic vegetation and to the degree of communication with the marine environment. Moreover, species richness and abundance of both macrophytes and macroinvertebrates were mainly dependent on depth, temperature, pH and concentration of total suspended materials (TSM). Results also showed that environmental variables such as depth, transparency/depth ratio, total P, chl-a, and TSM differed significantly between the two lagoons. In order to assess the ecological quality of the study sites, the functional ISD index has been applied. From the preliminary results it seems that ISD index, based on the biomass size structure of the macroinvertebrate communities, is more appropriate for the assessment of the ecological status for these particular ecosystems. The development of a monitoring team is essential for the protection and management of these ecologically important ecosystems. Further investigation is necessary to examine the relationships between benthic macroinvertebrates and aquatic macrophytes, the use of biotic indices to the evaluation for lagoonal ecosystems' ecological status and the relation between the hydrological processes and the biodiversity patterns of the biotic elements.

Fyttis, G.; Reizopoulou, S.; Papastergiadou, E.

2012-04-01

7

Natural and planted flora of the log mountain surface - mined demonstration area, Bell County, Kentucky  

SciTech Connect

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.

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)

1996-12-31

8

The tannosome is an organelle forming condensed tannins in the chlorophyllous organs of Tracheophyta  

PubMed Central

Background and Aims Condensed tannins (also called proanthocyanidins) are widespread polymers of catechins and are essential for the defence mechanisms of vascular plants (Tracheophyta). A large body of evidence argues for the synthesis of monomeric epicatechin on the cytosolic face of the endoplasmic reticulum and its transport to the vacuole, although the site of its polymerization into tannins remains to be elucidated. The aim of the study was to re-examine the cellular frame of tannin polymerization in various representatives of the Tracheophyta. Methods Light microscopy epifluorescence, confocal microscopy, transmission electron microscopy (TEM), chemical analysis of tannins following cell fractionation, and immunocytochemistry were used as independent methods on tannin-rich samples from various organs from Cycadophyta, Ginkgophyta, Equisetophyta, Pteridophyta, Coniferophyta and Magnoliophyta. Tissues were fixed in a caffeine–glutaraldehyde mixture and examined by TEM. Other fresh samples were incubated with primary antibodies against proteins from both chloroplastic envelopes and a thylakoidal chlorophyll-carrying protein; they were also incubated with gelatin–Oregon Green, a fluorescent marker of condensed tannins. Coupled spectral analyses of chlorophyll and tannins were carried out by confocal microscopy on fresh tissues and tannin-rich accretions obtained through cell fractionation; chemical analyses of tannins and chlorophylls were also performed on the accretions. Key Results and Conclusions The presence of the three different chloroplast membranes inside vacuolar accretions that constitute the typical form of tannin storage in vascular plants was established in fresh tissues as well as in purified organelles, using several independent methods. Tannins are polymerized in a new chloroplast-derived organelle, the tannosome. These are formed by pearling of the thylakoids into 30 nm spheres, which are then encapsulated in a tannosome shuttle formed by budding from the chloroplast and bound by a membrane resulting from the fusion of both chloroplast envelopes. The shuttle conveys numerous tannosomes through the cytoplasm towards the vacuole in which it is then incorporated by invagination of the tonoplast. Finally, shuttles bound by a portion of tonoplast aggregate into tannin accretions which are stored in the vacuole. Polymerization of tannins occurs inside the tannosome regardless of the compartment being crossed. A complete sequence of events apparently valid in all studied Tracheophyta is described. PMID:24026439

Brillouet, Jean-Marc; Romieu, Charles; Schoefs, Benoit; Solymosi, Katalin; Cheynier, Veronique; Fulcrand, Helene; Verdeil, Jean-Luc; Conejero, Genevieve

2013-01-01