Phytoliths as emerging taxonomic tools for identification of. Due to discovery of the fossil plants, the classification of pteridophytes has undergone vast changes in the recent past. As they produce neither flowers nor seeds, they are referred to as cryptogams. They formed the dominant part of the earths during palaeozoic and mesozoic periods. Mar 08, 2016 the pteridophytes are found in cool, damp, shady places though some may flourish well in sandysoil conditions.
However, in pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves. In this article we will discuss about the classification of pteridophytes. Current knowledge suggests that phytoliths are restricted to the vascular plants, with high production levels and common familyspecific forms occurring in the pteridophytes tree ferns and horsetails, basal angiosperms magnolias, and monocotyledons particularly. Pteridophytes introduction, authors and addresses, systematic list, glossary, and key to tribes. However, the pteridophytes differ from mosses and seed plants in that both generations are independent and freeliving. Be aware that some people use this term just to refer to ferns. They are preserved in the form of fossils or coal deposits. Occurrence and evolution of pteridophytes biology boom. Ethnomedicinal uses of pteridophytes of kumaun himalaya upreti, et al. Pteridophytes may represent the closest living relatives sister group to the seed plants. The different species of selaginella are grown as the garden plants. Pteridophytes ferns and fern allies the plant list.
Among the pteridophytes species of equisetaceae are heavy silicon accumulators 17. They dont have conducting tissues for transportation of water and minerals. The entire plant of this species is used as medicine in ayurveda, sidha and unani. Some pteridophytes are further united by the presence of a single leaf per vein, an arrangement known as a microphyll. There is evidence that roots evolved from subterranean portions of stems. The sexuality of pteridophytic gametophytes can be classified as follows. A first checklist of the pteridophytes of togo west africa. Phytoliths as emerging taxonomic tools for identification. Surface soil phytoliths as vegetation and altitude indicators.
The printed version, however, was effectively published on 6 june 20. There are fifty types of phytoliths, including pteridophyta, conifers, broadleaved, cyperaceae, bambusoideae, chloridoideae, panicoideae. More recently phytoliths have been extracted and described from pteridophytes ferns fig. The pteridophytes are an economically important group of plants. Ethnomedicinal uses of pteridophytes of kumaon himalaya. In this course we are going to use the term pteridophyte to refer to nonseed vascular plants, i. The pteridophytes ferns and fern allies pteridophytes are vascular plants and have leaves known as fronds, roots and sometimes true stems, and tree ferns have full trunks. The cryptogamia was further divided into thallophyta. Medicinal pteridophytes of madhya pradesh balendra pratap singh and ravi upadhyay abstract the present study mainly focuses on the medicinal pteridophytes are widely used by tribalrural people of the madhya pradesh. Phytoliths are ergastic siliceous substances present abundantly within.
Sumita, assistant professor, department of botany, pggc11, chandigarh. They probably evolved from the green algae at about the same. Mar 23, 2018 the pteridophytes are an economically important group of plants. Study of phytoliths of pteridophytes is an emerging area of research. These are inorganic and thus resistant to the forces of decay that cause the destruction of other. A few pteridophytes are aquatic while still others are. Some recent findings have shown that phytoliths may have systematic and. The sporophyte is the conspicuous and familiar plant body. A few pteridophytes are aquatic while still others are epiphytes. Pteridophyte definition of pteridophyte by merriamwebster. Many plant groups are known to accumulate silica in solid form in and between the cells and tissues and hence create the structures commonly known as phytoliths.
As in seed plants, the greatest diversity of pteridophytes is found in the tropics, with only about six hundred species adapted for life in temperate climates. Jan 23, 2017 occurence most of the pteridophytes are terrestrial and grow in moist and shady places while some flourish well in open, dry places especially in xeric conditions selaginella lepidophylla. The current trends in the subject are explained in a simple, lucid and understandablewriting style. In the recent advancements in identification of plant species, phytoliths have found an immense role in the identification of plants at different levels of taxonomic hierarchy. Clubmosses, quillworts, and spikemosses have this simple leaf arrangement.
Pteridophyta is the most highly evolved group among the cryptogams. These phytoliths create replicas of the structures where. On the basis of their anatomy jeffrey in 1902 divided the vascular plants into two types or stocks. Experiments with some pteridophytes have revealed various aspects of silica uptake, deposition and biological effects. The body of the sporophyte is well differentiated into roots, stem and leaves. Phytoliths are functionally significant for the development and survival of pteridophytes. Summary solid biosilica phytoliths deposited in plant tissues is thought to. Pteridophytes constitute a significant and important group in the plant kingdom.
The plant list includes 46,428 scientific plant names of species rank for the pteridophytes. Pdf study of phytoliths of pteridophytes is an emerging area of research. Economic importance of pteridophytes,several ferns such as angiopteris, asplenium, marattia, microsorium, nephrolepis, phymatodes, etc. Instead, the water and minerals flow from the surface of the plant cell to cell in the plants body. Phytolith spectra of some eastern himalayan pteridophytes. Pteridophyta is designed to fulfill the needs of undergraduate and postgraduate students of botany. Engler 1909 included the bryophyta and pteridophyta under embryophyta. Seed plants include the angiosperms, the conifers, and a smaller assortment of other plants. Haeckel 1866 called these groups of plants as pteridophytes because of their pinnate or feather like fronds leaves. Phytolith data in peat profile over the past 0 years in the xishan. They are psilopsida, psilotopsida, lycopsida, sphenopsida, pteropsida and progymnospermopsida. As many pteridophytes plant species belonging to many types of medicine are d. A pteridophyte is a vascular plant with xylem and phloem that disperses spores.
Phytoliths of pteridophytes can provide important insights into past vegetations piperno, 2006. Scribd is the worlds largest social reading and publishing site. In certain pteridophytes the sporangia are produced within specialized structure, the sporocarps e. This pdf version does not have an isbn or issn and is not therefore effectively published melbourne code, art. Pteridophytes plants spore free 30day trial scribd. Some pteridophytes are aquatic and some are epiphytes.
In addition to the abovementioned, the pteridophyte phytolith type fig. Pteridophytes ferns and lycophytes are freesporing vascular plants that have a life cycle with alternating, freeliving gametophyte and sporophyte phases that are independent at maturity. Some recent findings have shown that phytoliths may have systematic and phylogenetic utility in pteridophytes. The modern classification of pteridophytes have been suggested by many scientist according to the sporne1975 pteridophytes have been classified into six classes. Significant silicon accumulation and the formation of phytoliths microscopic amorphous silica bodies occur in various pteridophytes, gymnosperms and angiosperms, but vary greatly among taxonomic groups hodson et al. Pteridophytes provide clues to evolution of roots and leaves 1. Pteridophyte definition of pteridophyte by the free dictionary. Literature on this aspect is limited but increasing. You might be surprised to learn that, in terms of biodiversity, b.
Publication date 1962 topics pteridophyta, botany morphology publisher. Current knowledge suggests that phytoliths are restricted to the vascular plants, with high production levels and common familyspecific forms occurring in the pteridophytes tree ferns and horsetails, basal angiosperms magnolias. Thus, these characteristics make them horticulturally important plants. A concept based exclusive material pteridophytes, gymnosperms. Pteridophyte definition is any of a division pteridophyta of vascular plants such as a fern that have roots, stems, and leaves but lack flowers or seeds. Pteridophytes pteridophytes is a general term for the vascular, free. Pteridophytes free download as powerpoint presentation. Most pteridophytes are terrestrial plants and thrive well in abundant moisture and shade while some flourish well in open, dry situations especially in xeric conditions. New publications have documented a diverse array of phytoliths from many regions around the globe, while new understandings have emerged as to how and why plants produce phytoliths. Some pteridophytes are aquatic marselia, azolla and some are epiphytes ophioglossum pendulum. Among the pteridophytes species of equisetaceae, there are heavy silicon accumulators which. The umbrella terms pteridophytes and ferns and fern allies were used to denote a group of spore bearing, seedless vascular plants that demonstrated many. Species of pteridophytes contained within the plant list belong to 35 plant families and 568 plant genera. The sporangium in all pteridophytes is initiated by the laying down of a crosswall in a superficial cell or a group of cells.
Apr, 2014 current knowledge suggests that phytoliths are restricted to the vascular plants, with high production levels and common familyspecific forms occurring in the pteridophytes tree ferns and horsetails, basal angiosperms magnolias, and monocotyledons particularly the grasses and sedges, eudicots daisies, melons 9, 10, 11. Like reptiles first true land animals that evolved after. Any of numerous vascular plants that reproduce by means of spores rather than seeds, including the ferns and related plants such as horsetails, and. It is speculated that life began in the oceans, and through millions of years of evolution, life slowly adapted on to dry land. Fronds in the largest species of ferns can reach some six metres in length. And among the first of the plants to truly live on land were the pteridophytes.
Pteridophytes, also known as vascular cryptogams and ferns and fern allies, comprise about 12 000 species of vascular plants that do not produce. Useful notes on the classification of pteridophytes. Plant kingdom thallophytes algae bryophytes pteridophytes. No data were found for the remaining 242 families 58.
Some of the characters of pteridophytes are as follows. In 1880, the cryptogams of the plant kingdom were divided. Firstly all the botanists divided the plant kingdom into two large groups cryptogamia and phanerogamia, linnaeus 1754 used the term cryptogams for the first time for those plants which did not possess visible sex organs. You may recall that in bryophytes the dominant phase in the life cycle is the gametophytic plant body. Table 1 showed that 225 pteridophytic species have been studied and phytoliths were detected in 168 species. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as cryptogams, meaning that their means of reproduction is hidden. Ferns, horsetails often treated as ferns, and lycophytes clubmosses, spikemosses, and quillworts are all pteridophytes. Classification of pteridophytes for a long time the division pteridophyta includedthe ferns, lycopods and horsetails. Most pteridophytes are terrestrial and grow in moist and shady places while some flourish well in open, dry places especially in xeric conditions. The bryophytes are a group of simple land plants which in many ways are an evolutionary dead end. These include cupressaceae junipers and cedars, pinaceae. Phytoliths as emerging taxonomic tools for identification of plants.
Abstractstudy of phytoliths of pteridophytes is an emerging area of research. Pteridophytes are seedless and they procreate through spores. Pteridophytes or pteridophyta, in the broad interpretation of the term, are vascular plants plants with xylem and phloem that reproduce and disperse via spores. Pteridophyta characteristics, life cycle, classification.
Eichler 1883 divided the plant kingdom into cryptogamia and phanerogamia. Pteridophytes biology encyclopedia plant, body, different. Among the angiosperms, silicon and phytoliths are more abundant in members of the poaceae. The umbrella terms pteridophytes and ferns and fern allies were used to denote a group of spore bearing, seedless vascular plants that demonstrated many aspects of early evolution of land plants and undergone considerable taxonomic treatments. The plant list includes a further 3,533 scientific plant names of infraspecific rank for the pteridophytes. Pteridophytes, and especially the sphenopsida horsetails, are known for their very high phytolith contents. Similar to the life cycle of seed plants, the pteridophytes also involves the alternation of generations in its life cycle. Phytoliths in pteridophytes the umbrella terms pteridophytes and ferns and fern allies were used to denote a group of spore bearing, seedless. Experiments with some pteridophytes have revealed various aspects of silica uptake, deposition and. Current knowledge suggests that phytoliths are restricted to the vascular plants, with high production levels and common familyspecific forms occurring in the pteridophytes tree ferns and horsetails, basal angiosperms magnolias, and monocotyledons particularly the grasses and sedges, eudicots daisies, melons 9, 10, 11. In 168 species studied, phytoliths were diagnostic in 121 species, might be diagnostic in 34 species and not diagnostic in species. Phytoliths of pteridophytes connecting repositories. Classification of pteridophyta linkedin slideshare.
178 1506 1541 685 1083 1366 1616 401 108 1496 346 1027 143 823 425 1368 1599 1428 1143 583 1449 120 507 1295 1510 1154 460 1610 710 1317 357 908 135 1133 999 13 903 226 1071 286 635 391 8 784 1247 473