Request pdf development of the sorus in tree ferns. The initial cells of the marginal meristem give rise to the soral receptacle in both groups of dicksoniaceous genera. Hand in hand with the reduction in size of single sporangia. Springer anton i 1950 problems of cytology and evolution in the pter. The sporophyte was the dominant phase of the life cycle of these early pteridophytes. Usually a fern is defined as a cryptogam with sporangia evolving from the leaf. You have been provided with a set of plates of fungi isolated from a diseased leaf, one chytridiomycota, one zygomycota, one ascomycota and one basidiomycota. Pteridophytes do not have seeds or flowers either, instead they also reproduce via spores. When sori develop on the leaves of house ferns, they are often mistaken for tiny. Sinha anil kumar diversity of microbes and cryptogams pteridophyta by.
What is one evolutionary advantage pteridophytes have over bryophytes. Student should be able to trace the evolution from fossil plants. The origin of the sporophyte in land plants represents a fundamental phase in plant evolution. The pteridophytes occupy the intermediate position in between the bryophytes on one hand and the phanerogams on the other. Problems of cytology and evolution in the pteridophyta.
Studies of soral development in the treefern family dicksoniaceae in comparison with the cyatheaceae led to 1 recognition of two basic patterns in the dicksoniaceae, 2 clarification of. Hand in hand with the reduction in size of single sporangia are seen more and more complex aggregations of sporangia known as sori. Pteridophytes introduction, authors and addresses, systematic list, glossary, and key to tribes. The first vascular plants rapidly diversified to cover the earth. It is speculated that life began in the oceans, and through millions of years of evolution, life slowly adapted on to dry land. You may recall that in bryophytes the dominant phase in the life cycle is the gametophytic plant body. The meristematic areathe region of new cell growththat produces them may continue its activities over a number of weeks, producing sporangia of all ages, older ones being pushed aside as new ones mature in their turn. Sumita, assistant professor, department of botany, pggc11, chandigarh. As they produce neither flowers nor seeds, they are referred to as cryptogams. Economic importance of pteridophytes,several ferns such as angiopteris, asplenium, marattia, microsorium, nephrolepis, phymatodes, etc. The outer indusium is initiated first, approximately at the same time as the receptacle.
At first you see forms vaguely resembling ferns and bit by bit the image becomes sharper. Mar 23, 2018 the pteridophytes are an economically important group of plants. The different species of selaginella are grown as the garden plants. The evolution, morphology, and development of fern leaves frontiers. The influence of soil evolution on pteridophyte diversification. 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. Since phase differentiation means an increase in complexity, marginal reproductive organs are considered advanced. Occurrence and evolution of pteridophytes biology boom. Types of stele and its evolution in pteridophytes youtube. Even today, many tribal communities and rural populations are dependent heavily upon the natural resources obtained from the surrounding forest regions for treatment of various ailments and diseases. The most characteristic feature of the pteridophytes is the presence. Thus, these characteristics make them horticulturally important plants. We summarize what is known about the molecular genetics of fern leaf development and what future studies might tell us about the evolution of fern leaf development. But trust me the first thing that you notice is the abundant foliage of fern plants.
Pteridophytes or pteridophyta, in the broad interpretation of the term, are vascular plants plants with xylem and phloem that reproduce and disperse via spores. Type of stelar system in pteridophytes all part inside endodermis are called stele. When you think of forests and woods, you can picture trees, abundant lush green ferns, and other plants. I the emergence of ferns is best to be compared with a looming up from the fog. On the basis of their anatomy jeffrey in 1902 divided the vascular plants into two types or stocks. Stelar evolution in pteridophytes ppt types of steles and its evolution in pteridophytes ppt what is stele. There are also some purely aquatic ferns such as water fern or water velvet salvinia molesta and mosquito ferns azolla species.
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. The three groups of bryophytes are morphologically distinct from one anoth er chopra 1968, but it is rarely recog nized that such distinctions are due to fundamental differences in morpho genetic design. Or the sporangia usually occur in clusters called sori or sorus,found on the underside fertile leaves. To some extent, phylogeny has always informed the classification of pteridophytes. The pteridophytes are an economically important group of plants. There are five types of protostele in pteridophytes they are 1. Several ferns such as angiopteris, asplenium, marattia, microsorium, nephrolepis, phymatodes, etc. This pdf version does not have an isbn or issn and is not therefore effectively published melbourne code, art. Plant kingdom thallophytes algae bryophytes pteridophytes.
Occurrence and evolution of pteridophytes with its origin and economic importance in pteridophyta is a group of ancient plants. Jan 23, 2017 introduction and definition the pteridophytes gk. Reproductive biology and evolution in the pteridophyta. Sep 04, 20 here we discuss the theories of leaf evolution in ferns, morphology, and diversity of fern leaves, and experimental results of fern leaf development.
Lloyd in flowering plants many of the diverse characteristics utilized in systematics to determine phylogenetic relationships represent direct adaptations to specific methods of pollination or reproduction. Read the introductory remarks and list of characteristics of the bryophytes p. Student should be able to differentiate between male and female reproductive organs and relate their structure and function to the production of new plants. Springer anton i 1950 problems of cytology and evolution in the pter mbridge. Further experiments on the developmental potentialities of leaf primordia in. In order to examine the relations between submarginal and marginal sori in the light of hagemanns hypothesis, various soral forms of ferns were analysed using the methodological framework of construction morphology sensu weber 1958.
The more primitive ferns are called eusporangiate ferns and their sori are made up of a clump of simple sporangia that release their spores by opening up a pore or slit see first pic. A few pteridophytes are aquatic while still others are epiphytes. A comparative assessment of the sori in selected pteridophytes. A concept based exclusive material pteridophytes, gymnosperms. They formed the dominant part of the earths during palaeozoic and mesozoic periods on soral evolution. And among the first of the plants to truly live on land were the pteridophytes. Sporangium and sorus the number of spores produced per sporangium ranges from 16 or 32 in some pteridophytes to more a type of chemical process. Types of stele and its evolution in pteridophytes vivek roys. Studies of soral development in the treefern family dicksoniaceae in. Experimental and analytical studies of pteridophytes xxxvi. Pteridophytes biology encyclopedia plant, body joilethbwinmi. Pteridophytes constitute a significant and important group in the plant kingdom.
Mar 08, 2016 the pteridophytes are found in cool, damp, shady places though some may flourish well in sandysoil conditions. Apr 10, 2006 another way you can look at sorus evolution is to consider the sporangia. They possess certain combinations of major characters which are not found in bryophytes or in phanerogams. How can one merge two species of bamboo to create a new. The stages in progressive evolution of sori can be depicted as follows.
Soral evolution in ferns presented by sumra kazbanu a. Classification of pteridophytes for a long time the division pteridophyta includedthe ferns, lycopods and horsetails. Unlike the bryophytes, these plants are in the mainstream of land plant evolution and eventually gave rise to the seed plants. Pteridophyta characteristics, life cycle, classification. Relations between submarginal and marginal sori in ferns. These ferns, in biological terms, are nothing but the pteridophytes, belonging to the division pteridophyta of the plant kingdom. A pteridophyte is a vascular plant with xylem and phloem that disperses spores. There are two theories regarding evolution of bryophytes.
The printed version, however, was effectively published on 6 june 20. Full text pdf online international interdisciplinary research journal. Pteridophytes ferns and fern allies the plant list. The evolution, morphology, and development of fern leaves. Stelar theory, components of stele, different types of steles in plants, protostele. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as cryptogams, meaning that their means of reproduction is hidden. Occurrence and evolution of pteridophytes with its origin and economic. Bryophytes, pteridophytes, gymnosperms, angiosperms pages. However, in pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves. Preliminary studies of soral morphogenesis in some cyatheaceous genera indicate that abaxial derivatives originate the sorus. Therefore the pericycle xylem and phloem together is called stele. What is one evolutionary advantage pteridophytes have over.
This pdf version does not have an isbn or issn and is not therefore effectively published. Another way you can look at sorus evolution is to consider the sporangia. Endodermis is the boundary between cortex and stele. Today this subject is controversial, and scarcely considered in textbooks and journals of botany, in spite of its importance. What can happen if its not installed correctly cbc marketplace duration. According to these theories the evolution in bryophytes is as follows. Pteridophyta is the most highly evolved group among the cryptogams. Energy healthy bacteria bacterial resistance and evolution gram staining alternations of generations bryophytes, pteridophytes, gymnosperms, angiosperms plant organization the amazing plant race phylum porifera.
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