An Initiatory Review on Bryophytes Diversity

Gajanand Modi1 , Bhumika Arora2 , Nivedan Bhardwaj3 , Jasina4 , Babita5

1School of Basic and Applied Science, RNB Global University, Bikaner 334601, Rajasthan, India

2Department of Botany, Akal University, Bathinda 151302, Punjab, India

3Department of Zoology, JCDM College, Sirsa, Haryana, India

4Department of Microbiology, KUK, India

Abstract: The varied group of terrestrial plants known as bryophytes is tiny in stature but has significant ecological effects. The biggest group of terrestrial plants, excluding flowering plants, they have over 23,000 known species worldwide. Mosses, hornworts, and liverworts are among the three phylogenetically separate lineages that make up the category. Mosses are typically regarded as a "key group" in our comprehension of the phylogenetically relatedness and origin of contemporary land plants (embryophytes). Bryophytes are able to live in a wide range of settings and have various growth habits. Although, mosses exhibit high species diversity, a major limitation in using mosses as study organisms has been the lack of basic floristic, ecological, and alpha-taxonomical knowledge of plants in many regions.

Keywords: Bryophytes, plants, Diversity, mosses, liverworts, hornworts etc.

Bryophytes are spore-producing, non-vascular terrestrial plants. They are the second largest plant genus after the flowering plants, but are less well known due to their size (Chandra et al., 2017). Mosses include a very separate group in the vegetation of land plants. They comprise around 23,000 species and form the most species-rich group of land plants. They have evolved to be an incomparable variety in size and structure. In India, mosses are represented by about 2850 taxa (Singh and Hajra 1996) and the Western Himalayas, Eastern Himalayas and Western Ghats represent biodiversity hotspots and acquire numerous endemic mosses. They can grow in extreme conditions. Most mosses are small, but some reach heights of up to half a meter or a little more. They can store large amounts of water, nutrients and carbon in their biomass. In most ecosystems, especially in peatlands, mosses act as carbon sinks, which is of great importance given the increasing levels of carbon dioxide around the world. Most mosses are ectohydric; they have the ability to absorb water, inorganic nutrients and mineral elements directly from the atmosphere rather than from the soil and substrate. Bryophytes are widely considered to be the oldest living land plants (Shaw and Renzaglia 2004). The properties of mosses relate them to green algae and both seem to have a common ancestor. Bryophytes have a short-lived dominant sporophytic and gametophytic phase. Bryophytes have a basal phylogenetic position among extant land plants, remnants of lineages that survived the spectacular radiation of land plants in the Devonian period (400 million years ago). Recent phylogenetic reconstructions of family relationships suggest that toadstools are the basic group of higher land plants; Moss and liverwort form a monophyletic sister group. By adapting to the irregular subaerial water supply, mosses in generally employed the alternative strategy of developing drought tolerance, photosynthesizing and growing during wet periods, and suspending metabolism during dry periods. Growth and sexual reproduction of mosses depend on external water and are therefore favored by a humid microclimate. They have a remarkable ability to regenerate from any plant fragment. Various reproductive modes play an important role in the life cycle of mosses, particularly in heavily disturbed stands (during 1997). Small, short mosses move their sperm with the help of early morning dewdrops. Moss spores travel long distances even with the help of the wind moving between continents by jet streams. The spore walls are highly protective and some spores are reported to remain viable for up to 40 years. Bryophytes can survive under stressful conditions such as cold, dry, shady. Bryophytes play an efficient role in filtering the nutrients that enter the soil by absorbing them directly from the atmosphere in the liquid phase. Bryophytes protect soil from erosion due to their interconnected, convoluted protonemata and gametophores, which cover exposed substrates and help increase the soil's water-holding capacity. The role of mosses in an ecosystem is determined by four properties: their ability to form soils, trap and retain moisture, exchange cations, and tolerate desiccation. These qualities are enhanced by its ability to multiply through frequent branching. Mosses such as Atrichum, Nardia, Pogonatum, Pohlia and Trematodon are soil erosion inhibitors due to their rigid structure and ability to regenerate. Bryophytes have an ecological association with microorganisms, protozoa, rotifers, Nematodes, earthworms, mollusks, insects, spiders and many other invertebrates (Gerson, 1982), as well as mosses in the ecosystem of 281 other plants and fungi.

ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor: 7.538

Volume 11 Issue II Feb 2023- Available at www.ijraset.com

Bryophytes are divided into three groups, namely liverworts, hornworts and musci. Cell ultrastructure and molecular biology confirmed that mosses themselves have three separate evolutionary patterns crowning liverworts (Hepaticopsida), tomentosum (Anthocerotopsida), and mosses (Bryopsida) (Shaw and Goffinet 2000).

The estimated number of hepatica species ranges from 6000 to 8000. Hepaticas are represented by about 850 species belonging to 141 genera and 52 families (Singh 2001). The leaf forms (young Maniopsid) are represented by almost 85% of liverwort species exhibit enormous morphological, anatomical and ecological diversity. Plants with leaf shoot systems are the most common habit in this class, S.., Cololejeunea, Frullania, Jubulopsis and Radula thalloid forms, e.g., Metzgeriales and Marchantiales are widely distributed in moist, shady, terrestrial, semiaquatic locations, especially in high altitude, dense subalpine and moist temperate forests. The spores are spread by the rotating movement of the wing blades and by the division of the sporophyte into four segments.

Hornwort consists of about 100-150 species in the world (Renzaglia and Vaughn 2000). They resemble some hepaticas only in the case of unspecialized thalloid gametophytes. Hornwort, they have colonies of Nostoc ventrally on their thallus. This alga exhibits a symbiotic nature that provides organic nitrogen for the metabolism of the toadstool thallus and provides nourishment (carbohydrates) and protection to the thallus. They possess a Cylindrical, horn-shaped sporangia (sporophyte). The release of the spores from the sporophyte occurs gradually over a long period of time. Its spores are spread by the movement of the water and not by the wind.