Diversity of pteridophyte flora in akamala forest station, thrissur. O the gametophytic and sporophytic generations are two independent plants not physically connected. In this article we will discuss about heterospory and seed habit in pteridophytes. Ferns, horsetails often treated as ferns, and lycophytes clubmosses, spikemosses, and quillworts are all pteridophytes. Habit and habitat and morphology biology discussion. What are the adaptations of bryophytes to land habitat.
Pdf diversity of pteridophytes in western ghats dr. O pteridophytes show much variation in form, size, and habitat. The exact mechanism involved remains controversial. Some plants are categorized in more than one of the following habits as appropriate to their characteristics. Heterospory and seed habitat in pteridophytes short notes heterospory and seed habitat. Field guide to the pteridophytes of chiang mai, thailand john rey c. Pteridophytes general characteristics free online biology. Evolutionary significance of heterospory and seed development in. The different species of selaginella are grown as the garden plants. You may recall that in bryophytes the dominant phase in the life cycle is the gametophytic plant body. 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. Pdf diversity of pteridophytes in western ghats researchgate.
Ferns can be used to illustrate the life cycle stages common to all pteridophytes. Mar 08, 2016 the pteridophytes are found in cool, damp, shady places though some may flourish well in sandysoil conditions. This genus is distributed worldwide in temperate and tropical regions of the. But trust me the first thing that you notice is the abundant foliage of fern plants. Pteridophyta is the most highly evolved group among the cryptogams.
Pteridophytes biology encyclopedia plant, body, different. Gymnosperms came from the greek root gymnos or naked with spermaor seed. And among the first of the plants to truly live on land were the pteridophytes. Pteridophyte definition of pteridophyte by merriamwebster. Characteristic of pteridophytes, shape size and habitat. Pteridophytes or pteridophyta, in the broad interpretation of the term, are vascular plants plants with xylem and phloem that reproduce and disperse via spores. Thus, these characteristics make them horticulturally important plants.
Secondary growth woody plants herbaceous plants habit. Ferns are not of major economic importance, but some are used for food. Habit, habitat, origin and geographical distribution of chilean vascular hydrophytes. Pteridophytes were dominant land plants during the carboniferous era and a major source of todays coal and oil. The chilean freshwater flora consists of 54 species. These ferns, in biological terms, are nothing but the pteridophytes, belonging to the division pteridophyta of the plant kingdom. Compared to other living land plants, they lack vascular tissue containing lignin and branched sporophytes bearing multiple sporangia. A few pteridophytes are aquatic while still others are epiphytes.
Pteridophytes may represent the closest living relatives sister group to the seed plants. Such peridophytes are known as homosporous and this phenomenon is known as homospory. Pteridophytes grow in a variety of habitats and in all climatic zones, but show. Origin of seeds and seed habitat in vascular plants from heterospory heterospory is a condition of the production of more than one type usually two of spores in a single plant. Many bryophytes grow on soil or on the persistent remains of their own growth, as well as on living or decomposing material of other plants. Most pteridophytes are terrestrial and grow in moist and shady places while some flourish well in open, dry places especially in xeric conditions. Though some studies have been done taking different habits and habitats of. Gymnosperms economical and ecological values albuerolyka.
Although the ovules are naked at the time of pollination, the seeds of gymnosperms are sometimes enclosed by other sporophyte tissues by the time they are mature. Most of the pteridophytes ferns and fernallies show their luxuriant and vigorous growth during the rainy season particularly in the hilly regions usually above 1400 m altitude. The sexuality of pteridophytic gametophytes can be classified as follows. It is speculated that life began in the oceans, and through millions of years of evolution, life slowly adapted on to dry land. All pteridophytes have a true alternation of generations, in which a dominant sporophyte generation produces spores through meiosis, and a freeliving gametophyte generation forms gametes egg and sperm by mitosis. General characteristics of pteridophytes key points easy biology. Heterospory and seed habit in pteridophytes botany.
Pteridophyta characteristics, life cycle, classification. Read the introductory remarks and list of characteristics of the bryophytes p. It has about 400 species, which are cosmopolitan in distribution. The habit and habitat of each species were recorded and sporulation period as. These plants posses some of the characteristics which are precursors of the seed habit and these are. Similar to the life cycle of seed plants, the pteridophytes also involves the alternation of generations in its life cycle. Most of the pteridophytes produce one kind of similar spore.
Economic importance of different members was assessed with the help of available information from various sources. Callado l bayu adji l piyakaset suksathan l wenni setyo lestani l dedy daernaedi contributing authors dian indah pratiwi l. The pteridophytes are an economically important group of plants. These are saprophytic fungi and grow on dead organic material. However, in pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves. Some bryophytes are unusually tolerant of extended periods of dryness and freezing, and, upon the return of moisture, they rapidly resume photosynthesis. As they produce neither flowers nor seeds, they are referred to as cryptogams. Heterospory and seed habitat in pteridophytes short notes heterospory and seed habitat origin of seeds and seed habitat in vascular plants from heterospory heterospory is the production of two or more types of spores. The sporophyte is the conspicuous and familiar plant body. However, the pteridophytes differ from mosses and seed plants in that both generations are independent and freeliving. Why are pteridophytes better adapted to dry land than bryophytes. Some members are aquatic azolla, marsilea, salvinia usually occurring in permanent ponds. Plant kingdom thallophytes algae bryophytes pteridophytes.
The bryophytes are a group of simple land plants which in many ways are an evolutionary dead end. Boufford this volume represents the fourth in a regularly appearing series that began in 1979 and that eventually will treat the. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. They had acquired certain characteristic features in the early geologic period that helped them to make their successful adaptation on land. General characteristics of pteridophytes key points easy. A survey is also given of their occurrence in lotic and lentic environments. Field guide to the pteridophytes of chiang mai, thailand issuu. The term bryophyte thus refers to a grade of lineages defined primarily by what they lack. Some pteridophytes do approach seedhabit and some fossil pteridophytes had. What is the lasting form of pteridophytes, the gametophyte or the.
Agavelike plant perennial monocot plants with long, narrow, often rigid and bayonetlike leaves, these succulent or hard and durable, longlived, often spinetipped and sometimes with spiny margins, produced as a rosette or. Heterospory and origin and evolution of seed habitat in land plants pteridophytes. O most of the present day pteridophytes are annual, terrestrial and herbaceous plants. Heterospory and seed habitat in pteridophytes easy biology. A fern polypodiopsida or polypodiophyta is a member of a group of vascular plants that. Available in the united states from columbia university press. Due to availability of favourable climatic conditions and suitable habitats for growth, the. A compact multicellular plant body was formed which helped in the conservation of water by reducing cell surface are exposed to dry land conditions. Have sufficient species that differ in habit requirements in relation to. David haig and mark westoby, selective forces in the emergence of the seed habit, biological journal of the linnean society, 38, 3, 215238, 2008. Heterospory and seed habitat origin of seeds and seed habitat in vascular plants from heterospory heterospory is the production of two or more types of spores. The evolution and diversification of epiphytic ferns pdf phd thesis. Traditionally organisms existing on the earth were classified into plants and animals based on nutrition, locomotion and.
A few pteridophytes are aquatic while still others are. Heterospory is a condition of the production of more than one type usually two of spores in a single plant. In this course we are going to use the term pteridophyte to refer to nonseed vascular plants, i. As with all plants, in pteridophytes, meiosis is sporic, meaning that cells of the sporophyte undergo meiosis and generate spores that then develop into the gametophyte via mitosis. General characters with power point presentation ppt. A seed is that ovule which contains an embryo developed as a result of fertilization. Classification of pteridophytes short classification of the ferns pdf.
The habit and branching of pinnatiramosus is similar to that of green algae in the caulerpales, but the presence of tracheidlike tubes is inconsistent with this interpretation39. The first page of the pdf of this article appears above. The adoption of heterospory and the retention and germination of a single megaspore within megasporangium to form a female gametophyte, led to the phenomenon of seed habit, a characteristic feature of the spermatophytes. Lycopodium is commonly known as club moss due to their moss like appearance and club shaped strobili. O the main plant body of pteridophyte is the sporophytic plant diploid.
One can get these fungi in abundance by keeping moist bread under bell jar for two or three days at suitable temperature in the laboratory. Be aware that some people use this term just to refer to ferns. On the basis of their anatomy jeffrey in 1902 divided the vascular plants into two types or stocks. Retention of the female gametophyte within the megasporangium on the parent plant for proper parental care of new embryo. A classification of its growth forms is made and the typical habitat of each of the species is analyzed. Habit, habitat, origin and geographical distribution of.
Some of the characters of pteridophytes are as follows. Some pteridophytes are aquatic and some are epiphytes. Here are the following adaptations in bryophytes to adapt land habitat. The printed version, however, was effectively published on 6 june 20. Let us also look at classification within angiosperms to understand some of the concerns that influenced the classification systems. This pdf version does not have an isbn or issn and is not therefore effectively published melbourne code, art. 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. However, there are some pteridophytes which produce two different types of spores differing in size. Were pteridophytes always less abundant than phanerogamic plants. The megaspore and microspore germinate to give rise female and male gametophyte respectively. Mar 23, 2018 the pteridophytes are an economically important group of plants. They are vascular, spore bearing plants and include ferns and fernallies. Most of the living pteridophytes are terrestrial, growing in moist and shady places. Heterospory and seed habitat in pteridophytes easy.
In other words, gymnosperms are naked seeded plants. Pdf ethnomedicinal importance of pteridophytes used by. Ornamental plants trees, landscaping food pine nuts pesto, etc. The pteridophytes grow in different habitats like moist or dry rocks and boulders, on tree trunks, as hydrophytes in lakes, ponds, etc. Classification of pteridophytes for a long time the division pteridophyta includedthe ferns, lycopods and horsetails. Multicellular plant body and conservation of water. Field guide to the pteridophytes of chiang mai, thailand. Books illustrations of pteridophytes japan, volume 4, edited by s. The earliest systems of classification used only gross superficial morphological characters such as habit, colour, number and shape of leaves, etc. The pteridophytes are the successful colonisers on land habit. Significance of gymnosperms ecological importance provide.
They probably evolved from the green algae at about the same. Although bryophytes and pteridophytes have gametes tha depend on water for fertilization, the emergence of conducting vessels in this last group facilitated life in a terrestrial environment. Seed plants include the angiosperms, the conifers, and a smaller assortment of other plants. The prominence of the gametophyte in the life cycle is also a shared feature of the three bryophyte lineages extant. Habit and habitat of genera mucor and rhizopus biology. 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. Extant pteridophytes are cosmopolitan but are much better represented in the humid tropics, with only a few families e. Slowly in higher organisms sexual dimorphism started to occur.
The origin of gymnosperms and the seed habit science. Now we come to the last group of nonflowering plants, the pteridophytes. The fungal mycelium looks like fine cottony threads on the. A pteridophyte is a vascular plant with xylem and phloem that disperses spores. A concept based exclusive material pteridophytes, gymnosperms.
Cont gymnosperms that occupy areas of the world with severe climatic conditions are adapted to conserving water. Oct 10, 2019 heterospory and origin and evolution of seed habitat in land plants pteridophytes. In pteridophytes, gametes are produced via mitosis from special cells of the gametophyte. With the commencement of monsoon about mid june, the ferns and fernallies start growing vigourously and luxuriantly. Heterosporous pteridophytes are the plants that produce two types of spores i. Wiley online library divya darshan pant and rita singh, on the possible occurrence of anisospory in some hepaticae, botanical journal of the linnean society, 100, 2, 183, 1989. Pteridophytes introduction, authors and addresses, systematic list, glossary, and key to tribes. Ethnomedicinal importance of pteridophytes used by chenchus of nallamalais, andhra pradesh, india. When you think of forests and woods, you can picture trees, abundant lush green ferns, and other plants. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as cryptogams, meaning that their means of reproduction is hidden.
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