Archive for Bryology
Refine
Year of publication
- 2012 (22) (remove)
Document Type
- Part of Periodical (22)
Language
- English (22) (remove)
Has Fulltext
- yes (22)
Is part of the Bibliography
- no (22)
Keywords
- Bryophytes (3)
- Algae (1)
- Anthocerotophyta (1)
- Assam (1)
- Association (1)
- Bryoflora (1)
- Bryology (1)
- Bryophyta (1)
- Bryophyte (1)
- Campylopodioideae (1)
149
A catalogue of 107 species of liverworts (Marchantiophyta) and 8 species of hornworts (Anthocerotophyta), recorded from Assam, India is presented. This includes three new records for India viz., Cololejeunea denticulata (Horik.) S. Hatt., C. inflata Steph., Plagiochila furcifolia Mitt., and three species viz., Cololejeunea desciscens Steph. Colura ari (Steph.) Steph., Lopholejeunea eulopha (Taylor) Schiffn. new to mainland. Twelve species are new record for Eastern Himalayan bryo-geographical territory, 20 species as new to Assam and seven species are endemic to Indian regions.
121
Bryophytes (mosses, liverworts and hornworts) are the most basal lineages among extant land plants. However, there is controversy regarding their monophyletic or paraphyletic origin. Moreover, the most basal group of bryophytes also remains questionable. Due to this it is a matter of debate which lineage of bryophytes acts as transition link between bryophytes and pteridophytes. In order to resolve these issues we conducted a bioinformatics analysis on available chloroplast genomes of 1 green alga, 5 bryophytes, 4 pteridophytes, and 6 gymnosperms. Our study is based on multiple genome analysis through whole proteome comparison. The higher number of orthologous identified in Anthoceros (a hornwort), in comparison to other bryophytes considered, against all pteridophytes strongly support hornworts as transition link between bryophytes and pteridophytes.
146
The determination of complete DNA sequence of mitochondrial genome of liverwort, Marchantia polymorpha, opens the way to study the structure and organization of mitochondrial genomes of bryophytes. Since then several studies to sequence mitochondrial genomes of various plant groups have been made. Consequently 71 mitochondrial genomes (as on September 28, 2012) of Viridiplantae are available in organelle genome resources database at National Center for Biotechnology Information. Among these mitochondrial genomes the lineage sampling of bryophytes are poorly represented with only three liverworts, two mosses and two hornworts. The present review deals with features of sequenced mitochondrial genomes of bryophytes.
143
Since the availability of first complete DNA sequence of chloroplast genome of Marchantia polymorpha several studies to determine the structure and organization of chloroplast genomes of various plant groups have been made. However the lineage sampling of bryophytes are poorly represented in complete chloroplast genome sequences (only three liverworts, two mosses and one hornwort). This review presents features of sequenced chloroplast genomes of bryophytes.
142
Bryophytes (liverworts, mosses and hornworts) hold the basal most position among extant land plants. The present study deals with comparative analysis of available mitochondrial genomes of bryophytes using bioinformatics tools. These mitochondrial genomes belong to 2 liverworts, 1 moss and 2 hornworts. The analysis is based on multiple genome analysis through whole proteome comparison to detect conservation between mitochondrial genomes of bryophytes.
145
District Rajouri harbours a rich floral and faunal diversity besides varying climatic zones namely sub-tropical, temperate and alpine. The region exhibit significant altitudinal variations ranging from 490 m. to 4700 m. The present study was conducted to report bryophytic elements of the study area as there is no previous work done on this aspect from the study area, except some stray references. A total of 44 bryophyte species belonging to 4 orders, 16 families and 21 genera were reported from the study area. A checklist of the reported plant species with family, distributional range and habitat is presented in the paper. Besides contributing to the regional and national biodiversity check list database, the present study has opened up a new window for the future studies on the various aspects of the reported taxa including extensive exploration for the updation of the present list and to study the conservational aspects of the disappearing bryoflora of the region.
152
127
Germinating tests with bryophytes were undertaken with three moss species and two hepatic species. For the first time these tests were performed with aquaceous extracts of bryophytes in contrast to previous studies in which seeds were directly placed on moist bryophytes. First tests showed an inhibition of the germination rate in 3 species but an increase of the germination in one species. A second study revealed that aquaceous as well as alcoholic extracts in high concentrations inhibited the growth of cress, highly diluted extracts promoted the growth. Other authors found either only germination promoting effects or both, promoting and inhibiting effects. Experiments with compounds extracted from bryophytes cited in the literature had only growth inhibiting effects. Brachythecium rutabulum revealed growth inhibiting effects in a previous but growth promoting effects in this study. The conflicting results are hard to explain and should stimulate further more detailed studies. They maybe due to various combinations of different concentrations of bryophyte extracts, different bryophyte species, different pH and different seeds but also contamination by dust, soil, bacteria and fungi .
123
The Chocó region in Colombia is one of the wettest rainforests regions in the world. Isolated for about 3 million years, it is known for its high rate of endemism in flowering plants, ferns, birds and butterflies. Bryophytes (mosses and liverworts) of this region, however, were very unsufficiently known. For this reason, a first survey of the bryoflora of the Chocó region was made in 1992 along a transect from sea level to 1800 m elevation. Apparently because of the high precipitation with up to 12 m annual rainfall, terrestrial species were found growing on bark or corticolous species on leaves. The cover of epiphytic bryophytes is higher than elsewhere, especially in the lowland forest which shows usually a low bryophyte cover. The percentage of mosses compared with that of liverworts is much lower than elsewhere. Mosses form only about 10% of the bryophyte cover in contrast to 40-50% in the according elevation in other rain forest regions.
125
Plants variable in size and appearence, from a few mm to more than 10 cm tall, in loose to dense tufts. Stems erect, simple, rarely branched, radiculose, sometimes densely tomentose; rhizoids reddish-brown to whitish. Leaves erect-patent, sometimes curled when dry or falcate (sometimes erect and falcate expressions in the same species), short to longly lanceolate, often subulate; margins entire or serrate at leaf tips; costa single, percurrent to short excurrent, sometimes hyaline excurrent, filling 1/6 to 4/5 of leaf width, in transverse-section with median deuter cells and dorsal stereids, rarely hyalocysts, ventrally either stereids or more rarely hyalocysts; laminal cells usually smooth, occasionally bulging mammillose, cell walls smooth; alar cells differentiated or not, when distinct, hyaline or reddish brown, inflated, thin-walled or incrassate, basal laminal cells mostly rectangular, thin-walled or incrassate, occasionally pitted, upper laminal cells quadrate to rectangular or oval, leaf border present in some taxa. Vegetative propagation by microphyllous branches, deciduous leaves or stem tips, or anisophyllous brood leaves in the axils of the upper leaves. Dioicous or autoicous. Perichaetia terminal, or occasionally pseudolateral by stem innovations, perichaetial leaves often different in shape, from sheathing base subulate. Seta mostly elongate (1-4 cm), rarely short (<1 cm) or almost absent, erect, in few genera flexuose, cygneously curved and twisted. Capsule immersed to more commonly exserted, inclined to suberect or erect, symmetric to asymmetric, short long-cylindrical to ovoid-cylindrical or ovoid,, smooth or furrowed when dry and empty; stomata present or absent; annulus present or absent. Operculum conical to long-rostrate. Peristome single, teeth 16, mostly divided 1/2 or more toward base, vertically striate below, distally papillose to papillose throughout. Calyptra cucullate, smooth, naked, base entire or ciliate. Spores almost smooth to coarsely papillose.