PTERIDOPHYTA
,CONTENT
• INTRODUCTION
• GENERAL CHARACTERISTICS
• HABITAT
• CLASSIFICATION
• REPRODUCTION
• ALTERNATION OF GENERATION
• ECONOMIC IMPORTANCE
,INTRODUCTION
The word Pteridophyta has Greek origin. Pteron means a “feather” and Phyton means
plants. The plants of this group have feather like fronds (ferns). The group of
pteridophyta included into Cryptogams with algae, fungi and Bryophytes. The algae,
fungi and bryophytes are called lower cryptogames while the Pteidophytes are called
higher cryptogams. Pteridophytes also called Vascular cryptogames, because only
pteridophytes have well developed conducting system among cryptogams. Due to this
reason they are the first true land plants. All cryptogams reproduce by means of
spores and do not produce seeds. The Peridophytes are assemblage of flowerless,
seedless, spore bearing vascular plants, that have successfully invaded the land.
Pteridophytes have a long fossil history on our planet. They are known from as far
back as 380 million years. Fossils of pteridophytes have been obtained from rock strata
belonging to Silurian and Devonian periods of the Palaeozoic era. So the Palaeozoic
era sometimes also called the “The age of pteridophyta”. The fossil Pteridophytes were
herbaceous as well as arborescent. The tree ferns, giant horse tails and arborescent
lycopods dominated the swampy landscapes of the ancient age. The present day
lycopods are the mere relicts the Lepidodendron like fossil arborescent lycopods. Only
present day ferns have nearby stature of their ancestors. Psilotum and Tmesipteris are
two surviving remains of psilopsids, conserve the primitive features of the first land
plants.
, GENERAL CHARACTERITICS
1 The main independent plant body is sporophyte, with vascular system. It
develops from the diploid zygote.
2 The pteridophytes grow mostly in cool, moist and shady places, but some are
aquatic (Marsilea, Salvinia, Azolla etc.) and few are xerophytic (Selaginella rupestris,
S. respanda, even some species of Marsilia, M. rajasthanensis, Marsilia condenseta
etc.). 3-Plants are differentiated into true roots, shoots and leaves. Some primitive
members lack true roots and well developed leaves (e.g; In members of Psilophytales
and Psilotales).
4 Except few woody tree ferns all living pteritophytes are herbaceous.
5 They may be dorsiventral or radial in symmetry with branched stems.
6 The leaves of ptridophyte may be scale like leaf (e.g. Equisetum), small sessile
leaves (e,g. Lycopodium and Selaginella) and large, petiolate compound leaves occurs
in true ferns.
7 The stem bears leaves which may be small microphyllous type in which the leaves
are quite small in relation to the stem (e.g. Lycopodium, Selaginella, Euisetum), or
megaphyllous type, in which the leaves are large in relation to the stem (e.g. ferns).
,CONTENT
• INTRODUCTION
• GENERAL CHARACTERISTICS
• HABITAT
• CLASSIFICATION
• REPRODUCTION
• ALTERNATION OF GENERATION
• ECONOMIC IMPORTANCE
,INTRODUCTION
The word Pteridophyta has Greek origin. Pteron means a “feather” and Phyton means
plants. The plants of this group have feather like fronds (ferns). The group of
pteridophyta included into Cryptogams with algae, fungi and Bryophytes. The algae,
fungi and bryophytes are called lower cryptogames while the Pteidophytes are called
higher cryptogams. Pteridophytes also called Vascular cryptogames, because only
pteridophytes have well developed conducting system among cryptogams. Due to this
reason they are the first true land plants. All cryptogams reproduce by means of
spores and do not produce seeds. The Peridophytes are assemblage of flowerless,
seedless, spore bearing vascular plants, that have successfully invaded the land.
Pteridophytes have a long fossil history on our planet. They are known from as far
back as 380 million years. Fossils of pteridophytes have been obtained from rock strata
belonging to Silurian and Devonian periods of the Palaeozoic era. So the Palaeozoic
era sometimes also called the “The age of pteridophyta”. The fossil Pteridophytes were
herbaceous as well as arborescent. The tree ferns, giant horse tails and arborescent
lycopods dominated the swampy landscapes of the ancient age. The present day
lycopods are the mere relicts the Lepidodendron like fossil arborescent lycopods. Only
present day ferns have nearby stature of their ancestors. Psilotum and Tmesipteris are
two surviving remains of psilopsids, conserve the primitive features of the first land
plants.
, GENERAL CHARACTERITICS
1 The main independent plant body is sporophyte, with vascular system. It
develops from the diploid zygote.
2 The pteridophytes grow mostly in cool, moist and shady places, but some are
aquatic (Marsilea, Salvinia, Azolla etc.) and few are xerophytic (Selaginella rupestris,
S. respanda, even some species of Marsilia, M. rajasthanensis, Marsilia condenseta
etc.). 3-Plants are differentiated into true roots, shoots and leaves. Some primitive
members lack true roots and well developed leaves (e.g; In members of Psilophytales
and Psilotales).
4 Except few woody tree ferns all living pteritophytes are herbaceous.
5 They may be dorsiventral or radial in symmetry with branched stems.
6 The leaves of ptridophyte may be scale like leaf (e.g. Equisetum), small sessile
leaves (e,g. Lycopodium and Selaginella) and large, petiolate compound leaves occurs
in true ferns.
7 The stem bears leaves which may be small microphyllous type in which the leaves
are quite small in relation to the stem (e.g. Lycopodium, Selaginella, Euisetum), or
megaphyllous type, in which the leaves are large in relation to the stem (e.g. ferns).
