vascular plants: pteridophyta (part 1)

39
VASCULAR PLANTS: PTERIDOPHYTA (SEEDLESS PLANTS)

Upload: sharmine-ballesteros

Post on 15-Apr-2017

1.049 views

Category:

Education


0 download

TRANSCRIPT

Page 1: Vascular Plants: Pteridophyta (part 1)

VASCULAR PLANTS:PTERIDOPHYTA(SEEDLESS PLANTS)

Page 2: Vascular Plants: Pteridophyta (part 1)

CLASSIFICATION• Kingdom: Plantae• Phylum: Pteridophyta• Sub-phylum:

• Phylum Psilotophyta (whisk ferns)

• Phylum Lycophyta (club mosses and quillworts)

• Phylum Equisetophyta (horsetails and scouring rashes)

• Phylum Polypodiophyta (ferns)

Page 3: Vascular Plants: Pteridophyta (part 1)

DEFINITION OF TERMS• Archegonia – female reproductive organ• Antheridium – male reproductive organ• Eusporangiate - when sporangium develop from group of initials• Gametophyte – a small, simple prothallus • Indusium – a thin membrane covering the sorus of a fern • Leptosporangiate – when sporangium develop from a single initial• Megaphylls – the leaves with more than one vein and a leaf trace is associated with leaf gap. They are often large and much divided.

Page 4: Vascular Plants: Pteridophyta (part 1)

DEFINITION OF TERMS• Microphylls – the leaves with a single vein whose trace is not associated with a leaf gap. They are photosynthetic and much smaller size.• Rhizomes – a specialized stem underground that produces adventitious roots.• Sorus/Sori – another term for sporangia• Sporangium – it is where the spores are produced• Sporophylls – are leaves that bears sporangia• Sporophyte – the main plant body• Vascular plants – are plants that have food-transporting phloem and water-transporting xylem tissues.

Page 5: Vascular Plants: Pteridophyta (part 1)
Page 6: Vascular Plants: Pteridophyta (part 1)

CHARACTERISTICS• Pteridophytes derived from Greek words, pteron “feather” + phyton “plants”.• It includes to the most primitive seedless vascular plants that reproduce by means of spores.• They are considered as the first true land plants that evolved after bryophytes. • They are sometimes called “Botanical Snakes”, “Snakes of plant kingdom” or “Amphibians of plant kingdom” because they depend on an external source of water for fertilization.• There are about 11,000 species of living Pteridophytes are known ranging from small aquatic plant to giant tree ferns of tropical forests.

Page 7: Vascular Plants: Pteridophyta (part 1)

• Pteridophytes do not produce seeds but rather produces spores.• Vascular tissues are present in all the vegetative parts of the plant body.• The sporophyte is the main plant body and it is mostly herbaceous. It is differentiated into roots, stem and leaves.• The branching of the stem may be of monopodial or dichotomous type.• The leaves may be smaller (microphylls) or larger (megaphylls).• The plants may be homosporous - producing only one type of spore or heterosporous - producing two different types of spores; smaller microspores and larger megaspores.

Page 8: Vascular Plants: Pteridophyta (part 1)

HABITAT• Some Pteridophyta are terrestrial and grow in moist and shady places while some are aquatic (hydrophyte) and sticking in other plant (epiphyte), or living in residue/waste of other plant (saprophyte).

Page 9: Vascular Plants: Pteridophyta (part 1)

REPRODUCTION• The spores germinate to produce a haploid gametophyte, called prothallus. The homosporous pteridophytes produce bisexual gametophytes while heterosporous pteridophytes produce unisexual gametophytes.• In gametophytes, reproduction is of oogamous type. The male sex organs are called antheridia and female sex organs are called archegonia. • Antheridia produce antherozoids and archegonia enclose the egg cell. Fertilization requires water. The diploid zygote is retained in the archegonial venter where it develops into an embryo. Subsequently it becomes a young sporophyte and grows into an independent adult plant. Thus the life cycle includes an alternation of diploid sporophytic generation with a haploid gametophytic generation. Sporophytic generation is dominant in the life cycle.

Page 10: Vascular Plants: Pteridophyta (part 1)
Page 11: Vascular Plants: Pteridophyta (part 1)

LIFE CYCLE OF PTERIDOPHYTES

Page 12: Vascular Plants: Pteridophyta (part 1)

ECONOMIC IMPORTANCE• Ornamental value: Ferns arc grown as ornamental plants in gardens and homes for their attractive foliage.• Drug, rhizomes and petioles of Dryopteris yield an anthelminthic drug.• Food. Sporocarps of Marsilea are rich source of starch and eaten for their nutritive value as food.

Page 13: Vascular Plants: Pteridophyta (part 1)

SUB-PHYLA OF SEEDLESS VASCULAR PLANTS

1. Phylum Psilotophyta (whisk ferns)• The sporophytes of this plant have neither true leaves nor roots, and stems and

rhizomes that fork evenly. 2. Phylum Lycophyta (club mosses and quillworts)• The stems of this plants are covered with microphylls that are

photosynthetic.3. Phylum Equisetophyta (horsetails and scouring rushes)• The sporophytes of these plants have ribbed stems containing silica deposit and

whorled, scalelike microphylls that lack chlorophyll.4. Phylum Polypodiophyta (ferns)• The sporophyte of ferns have megaphylls that are often large and much divided.

FERN AND FERN ALLIES

Page 14: Vascular Plants: Pteridophyta (part 1)

Division Equisetophyta

THE HORSETAILS AND SCOURING RUSHES

Page 15: Vascular Plants: Pteridophyta (part 1)

CLASSIFICATION• Kingdom: Plantae• Phylum: Pteridophyta• Class: Equisetopsida• Order: Equisetales• Family: Equisetaceae• Genus: Equisetum•Species: E. arvense

Page 16: Vascular Plants: Pteridophyta (part 1)

GENUS: EQUISETUM Common names: Horsetail, snake grass, puzzle grass• Derived from the Latin, equus "horse" + seta "bristle".• It is the only living genus in Equisetaceae, a family of vascular plants that reproduce by spores rather than seeds or flowers.• It is a "living fossil" as it is the only living genus of the entire class Equisetopsida, which was much more diverse in Devonian Period (400 million years ago). • Most horsetails grow in damp or marshy habitats, but some can grow in drier soil.

Page 17: Vascular Plants: Pteridophyta (part 1)

Horsetail – branchedScouring Rushes – unbranched

Page 18: Vascular Plants: Pteridophyta (part 1)

STRUCTURE AND FORM• They are perennial plants, either herbaceous or evergreen.• They typically grow less than 1.3 meters (4 feet) tall, but in some tropical and coastal forest exceed 4.6 meters (15 feet) in height.• They have tiny, scale-like leaves arranged in whorls at the nodes of its stem.• These leaves are fused together at their bases, forming a collar.• They are green when they first appear, but they soon wither and bleach.

Page 19: Vascular Plants: Pteridophyta (part 1)

• All photosynthesis occurs in the stem.• The stems are distinctly ribbed and

have nodes and internodes.• There are numerous stomata in the

grooves between the ribs.• The aerial stems develop horizontal

rhizomes, which also have regular nodes, internodes and ribs. In some species, the rhizomes have adventitious roots and may form extensive branching system as much as 2 meters (6.5 feet) below the surface.

Page 20: Vascular Plants: Pteridophyta (part 1)

• Epidermis is where the silica is deposited on the inner walls of epidermal cells.• Vertical ridges provide the main support for the plant as they are packed with sclerenchyma, which occurs in the outer cortex.• The pith breaks down at maturity, leaving a hollow central canal, reduces the weight of the stem and the chief supporting structures are concentrated towards the outside, increasing the strength of the stem and its resistance to buckling.

INTERNAL STRUCTURE

Page 21: Vascular Plants: Pteridophyta (part 1)

• Two smaller canals outside of the pith:• Carinal Canals – a water conduction; inner cylinder• Vallecular Canals – air spaces; outer cylinder

– it serve for respiration and to reduce weight hello world!!!!!! and increase stem strength.

•Chlorophyllous tissue is the main photosynthetic tissue and opens to the outside air via stomata.•Vascular bundles consists of xylem and phloem.

INTERNAL STRUCTURE

Page 22: Vascular Plants: Pteridophyta (part 1)

CROSS SECTION OF HORSETAIL’S STEM

Page 23: Vascular Plants: Pteridophyta (part 1)

REPRODUCTION• Equisetum involves sexual reproduction,

and asexual reproduction by the process of fragmentation.• Strobilus is a small, cone-like structure

that develops at the tips of the photosynthetic stems. It is usually about 2 to 4 cm long. Its surface has a numerous hexagonal, dovetailing plates which marks the top of sporangiophore that has 5 to 10 elongate sporangia connected to the rim.

Page 24: Vascular Plants: Pteridophyta (part 1)

STROBILUS

Page 25: Vascular Plants: Pteridophyta (part 1)

REPRODUCTION• When sporangia reach maturity, the sporangiophore separately lightly from its axis and it releases spores. • The sporocytes undergo meiosis, distinctive-appearing green spores are produced. The spores have four ribbon-like appendages, called elaters, that are slightly extended at the tips.• While the spores are being carried by air current, the elaters extended like wings. When the spores enters the humid air pocket above the damp area below, the elaters coil, causing the spore to drop in an area that is more likely to start germination and growth.

Page 26: Vascular Plants: Pteridophyta (part 1)

• Germination of spores occurs within a week of release. Lobed, cushion-like, green gametophytes develop.• Each gametophyte has lobes that house the antheridia, which produce sperm, and the archegonia, which produce eggs. • The egg is fertilized by the sperm in the archegonium, and diploid zygote begins to grow inside the archegonium. This matures into the sporophyte plant.

Page 27: Vascular Plants: Pteridophyta (part 1)

LIFE CYCLE OF EQUISETUM

Page 28: Vascular Plants: Pteridophyta (part 1)

ECONOMIC IMPORTANCE• The young plants are eaten cooked or raw by Native Americans in the

Pacific Northwest and in Japan, it is eaten like asparagus, a dish called tsukushi.• The people of ancient Rome would used it to make tea as well as a

thickening powder.• The plants are used as a dye and give a soft green color. • Horsetail was often used by Indians to polish wooden tools• The silica is used to clean pans and pots and also for polishing brass

and hardwood furniture and flooring.• Equisetum species are often used to analyze gold concentrations.

Page 29: Vascular Plants: Pteridophyta (part 1)

MEDICINAL USES• Extracts and other preparations of E. arvense have served as herbal remedies, with records dating to ancient Greek and Roman medical sources.• Its uses include treatments to stop bleeding, treat tuberculosis, to heal wounds and ulcers, and to treat kidney ailments.• People found silica from horsetail, so it is used to make medicine of diuretic and it helps relieve kidney stones and urinary tract infections. • In addition it helps combat osteoporosis, because horsetails cause increasing bone density. • Some Native American tribes burned the stems and used the ashes to alleviate sore mouths or applied the ashes to severe burns.• Other tribes ate the strobili of scouring rush to cure diarrhea, and others boiled stems in water to make a hair wash for control of lice, mites and fleas.

Page 30: Vascular Plants: Pteridophyta (part 1)

SOME SPECIES OF EQUISETUM• E. hyemale – Rough horsetail • E. ramosissimum – Branched horsetail • E. scirpoides – Dwarf horsetail • E. arvense – Field horsetail• E. fluviatile L. – Water Horsetail• E. palustre L. – Marsh Horsetail• E. pratense – Meadow Horsetail• E. variegatum – Variegated horsetail

• E. sylvaticum L. – Wood Horsetail• E. laevigatum – Smooth Horsetail• E. telmateia – Northern giant horsetail

(2.5 m)• E. giganteum – Southern giant

horsetail (5 m)• E. myriochaetum – Mexican giant

horsetail (8 m)

Page 31: Vascular Plants: Pteridophyta (part 1)

PHYLUM PSILOTOPHYTATHE WHISK FERNS

Page 32: Vascular Plants: Pteridophyta (part 1)

• A division of vascular plants consisting of only two genera, Psilotum and Tmesipteris, with very few species. These plants are characterized by the lack of roots, and, in one species, leaves are lacking also. • The green, photosynthetic stem is well-developed. The gametophyte plant, arising from germination of a spore, is small and colorless, and derives its nutrition through a specialized association with a fungus. • Sexual structures on the gametophyte produce eggs and sperm. The motile sperm, with numerous flagella, are able to swim through a film of water to the egg. The fertilized egg, or zygote, first absorbs nourishment from the gametophyte, and later becomes photosynthetic and self-sustaining. The life cycle is very much like that of ferns.

Page 33: Vascular Plants: Pteridophyta (part 1)

• The Psilotophyta are small rootless plants that are epiphytic or grow on humus-rich soil and in rock crevices. The underground rhizomatous organs contain fungous hyphae (endotrophic mycorrhiza). The stems are covered by an epidermis with stomata that are structurally similar to the primitive stomata of fossil Rhyniaceae.

• There are two species of Psilotum, each having small scale-like leaves and repeatedly dichotomously branching stems that are 20–100 cm long. Both species are found in the tropics and subtropics of both hemispheres. The genus Tmesipteris also has two species, whose stems measure 5–40 cm long and bear well-developed blades (sporophylls) in the upper portion. The Tmesipteris are found primarily in Australia, Tasmania, New Zealand, and Polynesia.

• The synangia that form on the Psilotophyta are bilocular or trilocular. The spores, as they sprout, give rise to underground gametophytes that lack chlorophyll and live saprophytically on fungi. The gametophytes do not differ from the young rhizomatous organs in size and form.

CHARACTERISTICS

Page 34: Vascular Plants: Pteridophyta (part 1)

Structure and form:•Sporophytes:

−Dichotomously forking stems Above ground stems arise from rhizomes

−Lack leaves and roots−Enations - tiny, green, superficially leaflike, veinless,

photosynthetic flaps of tissue−Roots, aided by mycorrhizal fungi, scattered along

rhizomes−Has spore-producing called synangia.

Page 35: Vascular Plants: Pteridophyta (part 1)

PSILOTUM (WHISK FERN)

• A genus of fern-like vascular plants, one of two genera in the family Psilotaceae, order Psilotales, and class Psilotopsida. The name of the genus is from Greek psilos = bare, referring to the lack of the usual plant organs, such as leaves.

Kingdom: PlantaeDivision: PteridophytaClass: PsiolotopsidaOrder: PsilotalesFamily: PsilotaceaeGenus: PsilotumSpecies: Psilotum nudum

Psilotum complanatum

Page 36: Vascular Plants: Pteridophyta (part 1)

Sporangia

Scale

Page 37: Vascular Plants: Pteridophyta (part 1)

TMESIPTERIS: THE “HANGING FORK FERN"

• A genus of fern-like vascular plants, one of two genera in the family Psilotaceae, order Psilotales, and class Psilotopsida. The fronds emerge directly from the fibrous root-mats which clad the trunks of mature tree ferns such as Dicksonia and Cyathea.

• Tmesipteris is from the Greek language, meaning a "cut fern", referring to the truncated leaf tips.

Kingdom: PlantaeDivision: PteridophytaClass: PsilotopsidaOrder: PsilotalesFamily: PsiitaceaeGenus: TmesipterisSpecies: Tmesipteris elongata

Page 38: Vascular Plants: Pteridophyta (part 1)

Reproduction:• Sporangia fused in 3s and produced at

tips of short branches• Gametophytes develop from spores

beneath ground− Branch dichotomously− No chlorophyll− Rhizoids aided by mycorrhizal

fungi− Archegonia and antheridia

scattered on surface• Zygote develops foot and rhizome• Rhizome separates from foot

Page 39: Vascular Plants: Pteridophyta (part 1)

END OF DISCUSSION