Akarsh_lake2006_29th DEc2006

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Transcript Akarsh_lake2006_29th DEc2006

By:- AKARSH.M
8th Standard
EMBASSY PUBLIC
SCHOOL
CONTENTS
INTRODUCION
HISTORY
GEOGRAPHICAL DISTRIBUTION
HABIT AND AHBITAT
LEAF
STEM
ROOTS
FLOWER
REPRODUCTION
GROWING OF ORCHIDS
USES OF ORCHIDS
VANILLA
MEDICINAL USES
CASE STUDY
CONCLUSION
INTRODUCTION
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Orchids (Orchidaceae family) are
the largest and most diverse of the
flowering plant (Angiospermae)
families, with 800 described
genera and 35,000 species.
Some sources give 30,000 species,
but the exact number is unknown
since classification differs greatly in
the academic world.
HISTORY
• The ancient Greeks were the first to
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take note of these strange plants.
Theophrastus who is often called as
father of Botany gave the name
“Orchids” to these groups of plants
on the basis of the resemblance of
paired underground tubers of these
plants to masculine anatomy.
Indian Vedic scripture also mention
about these plants under the name
“Vrinda”, the Sanskrit name of
orchids.
GEOGRAPHICAL
DISTRIBUTION
• Orchids are found everywhere,
majority of the orchids known are
natives of tropical countries and
occur in their greatest diversity in
humid tropical forests.
• India has about 1,600 species, out
of which about 200 are found in
South India especially in the
Western Ghats and in Assam
nearly 800 species are known.
• However, nowhere else are
orchids in so much abundance and
so beautiful as along the 1,500
mile Himalayan belt Kalimpong
which is rightly called as ‘Orchid
Heaven’.
HABIT AND HABITAT
• Orchids are perennial herbs with
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simple leaves clustered all along the
stem. They usually have fleshy or
swollen stems called as pseudobulbs
and on the basis of their growth
pattern they are classified as
monopodial (single) or sympodial
orchids (many).
In many a cases orchids are valued for
their leaves instead of their flowers
and are called jewel orchids.
Orchids mostly grow as epiphytes i.e.
adhering to the main stem or branches
of different plants or moss-covered
rocks fixing themselves with their
strong roots. Orchids represent all the
possible colours. However , there is
no black orchid which exists only in
fairy tales.
LEAF
• Orchids have simple leaves with
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parallel veins.
The leaves can be enormous or
minute, or they can even be lacking.
The leaves of most orchids live on,
attached to their pseudobulbs, for
several years.
The leaves of some species can be
most beautiful
STEM
• The stem of an orchid determines
the habit of the species. Each type
of stem can grow in one of these
two ways:
• Monopodial (“one-footed”)
growth. The new shoots grow
upwards from a single stem,
originating in the end bud of the
old shoots.
• Sympodial (“many-footed”)
growth. The plant produces a
series of adjacent shoots which
grow to a certain size, bloom, then
stop growing, to be replaced by
the next growth.
ROOTS
• All orchids are perennial herbs, lacking
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any permanent woody structure.
Some orchids are terrestrial, growing
rooted in the soil. Terrestrial orchids
may be rhizomatous. These act as
storage organs for food and water.
Terrestrials are mostly found in colder
climates.
A great many orchids are epiphytes,
which do not require soil and use trees
for support. They occur in warmer
regions. Epiphytic orchids have
modified aerial roots which help them
to absorb the moisture from the
atmosphere. The aerial roots of
epiphytes that lack leaves have an
additional function. They contain
chlorophyll and take up carbon-dioxide.
FLOWER
• The orchid flowers are irregular,
extremely variable in size and
shape with sparkling texture; they
emit the fragrance of lemons,
cloves or fresh lavender oil.
• The flower has its part in threes, 3
sepals and 3 petals (collectively
called as tepals) , similar to each
other and sub similar to sepals.
• The third petal is different and
distinctive and is called labellum
or the lip.
REPRODUCTION
• The reproductive organs of the
orchids, the stamens and the pistil
are condensed and form a
complex body the column.
• Orchids are cross-pollinated by
insects, birds etc, and to achieve
this they have adored many
contrivances like mimicry and
twisting of the flower on its stalk
to face its pollinating agent.
• The seeds of orchids are
extremely small and minute-like
powder. A million of them are
found in one capsule and are
scattered by wind when the fruit
bursts open.
GROWING OF ORCHIDS
• Orchids need aeration, good
drainage, much humus and
humidity. Depending upon the
growth habitat the orchids are
classified as epiphytic or
terrestrial, the orchids.
• The orchids are best watered by
indirect methods like spraying or
sprinkling. Coconut water is
very good for the growth of
orchids.
• Orchids in general grow better if
undisturbed. It is rightly said that
orchids die in most of the cases on
account of over care than neglect.
USES OF ORCHIDS
• Orchids are well known mainly as
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ornamentals, some of them are said to
be of high medicinal value.
Salep from orchid tubers has been
used for centuries as emollient,
demulcent and as aphrodisiac.
Sap of some of the species is
supposed to be highly styptic.
The famous Vanillin used for
flavouring ice creams and delicacies
throughout the world comes from the
pods of an orchid Vanilla planifolia.
Lastly, mention must be made about
the recently discovered fungistatic
compounds called “Phytoalexins”
which were first discovered in
orchids, these are naturally produced
fungicides by plant in response to
fungal infection.
VANILLA
• Vanilla, Vanilla planifolia (and other
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two Vanilla species less commonly
grown), is used as a flavouring agent
which gives a cooling effect.
Madagascar is the leading producer,
producing in 2005, 3 million metric
tons (of a world total of 7.3 million
metric tons).
Besides its use as a flavouring, It is
also used in fragrances and
perfumes.
MEDICINAL USES
Many of the orchids have a medicinal value like some listed below
Bletilla striata- This plant is used as herbal medicine in Chinese Materia
Medica for the treatment of dysentery, fever, malignant ulcers,
gastrointestinal disorder, anthrax, malaria, eye diseases, ringworm,
tumers, coughs, chest pains etc.
Cypripedium pubescens- It has sedative, hypnotic, antispasmodic properties and it is an
excellent nervine tonic. It is used against stress, helps to elevate mood, depression and eases
muscles.
Dendrobium- Malaysians have used this plant for affections of the brain and nerves. The
flowers and leaves are useful for cholera. The powdered leaves have been used for decreasing
pimples.
Gastrodia elata- It has been included in the Chinese Materia Medica and guides over the
centuries and attributed to possess magical properties such as expelling all kinds of poisons,
giving strength and virility, improving circulation and memory.
Vanda roxburghii- The plant is reported to have anti-inflammatory properties and is widely
used against arthritis.
Vanda tesellata- Whole plant contains an unknown glucoside which stimulates all the organs of
the body and therefore used in medical preparations especially arthritis.
CASE STUDY
A case study was conducted on the medicinal usage of orchids.
The study reports that fresh rhizomes and aerial parts of orchids are commonly used to
cure human and veterinary diseases by tribes like Kondareddies, Koyas, Valmikis,
Nukadoras and Yanadis etc.
Acampe praemorsa
Uses: Whole plant is crushed with egg albumin and calcium paste applied tied with
bandaging for settling fractures by Koyas.
Bulbophyllum neilgherrense
Uses: Tubers of this plant are consumed for good health by Valmikis.
Cymbidium aloifolium
Uses: Aerial roots made into paste and plastered tightly on fractured bones and also to cure
foot cracks by Koyas. Mucilage from the leaves helps to stop bleeding after a leech bite.
Dendrobium herbaceous
Uses: Tender tip juice is used for earache by Nukadoras and Valmikis.
Habenaria plantaginea
Uses: Tubers ground with black pepper and garlic used to cure chest pain and stomach ache
by Koyas.
Habenaria hollandiana
Uses: Fresh plant paste applied for scorpion sting by Kondareddies and Valmikis.
Geodorum densiflorum
Uses: Root paste used to cure insect bite and wounds.
Habenaria roxburghii
Uses: Tubers with garlic and pepper used to cure snake bite.
Malaxis acuminate
Uses: Pseudobulbs used in ‘Ayurveda’ system of medicine as ingredient of ‘Ashtawarga’ tonic
preparation.
Oberonia wightiana
Uses: Leaves crushed with calcium, salt and turmeric paste tied with bandage for external
tumors by Koyas.
Vanda tesellata
Uses: Dried stem burnt and fumes spread out in home prevent children from catching fever
by Koyas.
CONCLUSION
Nature is the mother of all. There’s no orphan in the world until we are in her
vigil. She can be regarded the best doctor, the best scientist and moreover the
best mentor to teach the ways of life. She allows us decipher things on our own
and in some other way we need to be grateful to her generosity. Orchids are one
among her generous ways. To safeguard and protect them is our onus. Orchids
have in varied uses and can replace any allopathic drugs sans side effects.
Biopiracy is the prevailing tension and the government should encourage the
research and development on orchids and make it more practical and available
for the next filial.
“Mother’s love has no equals”