Archive for Bryology
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129
In succession of terrestrial ecosystem, bryophytes, algae and lichens constitute the primary components. Not only phylogenetically but also physically they are related to each other, as they are also found in close association and intermixed with each other on same substratum. A chlorophycean alga Ulothrix zonata (Weber & Mohr) Kützing has been found growing as an epiphyte on moss Macromitrium sulcatum (Hook.) Brid.. The association is peculiar as the algal filaments form a close net over the surface of moss leaves and axis.
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.
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.
140
Bryoflora of Munsyari and Dharchula Tehsil of Pithoragarh, Uttarakhand, Western Himalayas, India
(2012)
Uttarakhand state of India comprises unique topographical conditions and hence is rich in bryophytes. In present work two Tehsils-Munsyari and Dharchula of Pithoragarh have been explored extensively to assess the bryophytic wealth of this district. A preliminary checklist has been prepared which revealed the occurrence of 51 taxa of bryophytes from this district.
119
Parson’s valley is an area explored for the first time in Indian Bryology; it is situated in Nilgiri hills (Western Ghats). The region is very conducive for the growth of liverworts and it is evident by the present study of recent collections from this area in which 27 taxa (under 12 genera and 5 families) of liverworts have been recorded, of which few are new to Nilgiri hills as well as south India.
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.
120
The development of and the changes in the classification of bryophytes are shown over the last two centuries. It is shown that, except for an early period, the bryophyte system was never totally revised but was always only slightly improved, in which the ideas of a bryophyte system has undergone some kind of evolution but was never drastically changed. Neither the evolution theory in the last century nor the results of cytology, phytochemistry, computerbased studies or genetics in this century had drastically altered the bryophyte system. The reasons for the never totally changed but always slightly improved classification of bryophytes seem to be that recognition of systematic units is based on certain principles such as hierachical classification, types and algorithms of comparison. Therefore it is postulated that no general changes in the classification of bryophytes are to be expected in the future.
122
Since the existence of Nilgiri hills, bryophyte- the miniatures of plant kingdom play an important and crucial role in the stabilization of Blue Mountains ecology. Unlike Himalayas, the landslides were rare in the area, but with the time and changing global environment it had become a common sight. Significantly ever increasing population and vehicular traffic is the prime reason for them, to cater the need, roads are periodically broadened by cutting road sides destroying the habitat as also the inhabiting species. Bryophytes, are efficient soil binders that regulate the soil moisture and provide substrate for future plant succession. The habitat loss and nudeness of substratum gives impetus to rapid soil erosion that further enhances the problem of their very survival. The present communication provides significance of these avascular cryptogams in environmental assessment, ecological balance and their role in decreasing the pore pressure to check land slides.
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 .
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.