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Orchid
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This website is committed to bring you
the best picture of orchid flower and
comprehensive information
about orchid.
You will
find beautiful orchid picture from
wild orchid and orchid species plus
hybrids.
All the
popular orchids like dendrobium orchid,
phalaenopsis orchid, oncidium orchid,
cattleya orchid and vanda orchid among
other are covered.
There are some tips how to grow
orchids and hybrids in particular.
You will find a “sea of orchid colors”
in the pictures from a Thai orchid
nursery, actually it’s a virtual orchid
show.
We also cover the most popular orchid
colors; this is white orchid, yellow
orchid, blue orchid and purple orchid.
There are also other colors, like
beautiful red cattleya, blue vanda, pink
dendrobium and other orchids with mixed
colors.
There are
beautiful orchid bouquets and other
flower arrangements plus orchid for
sale. Orchid wholesale, orchid seeds
and seedlings of cattleya, cymbidium,
dendrobium, oncidium, paphiopedilum,
phal, phalaenopsis, vanda in flasks. |
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The orchid family--Orchidaceae--has
a greater variety of species than
any other plant family on Earth:
naturally occurring species
number over 30,000, and
artificially created hybrids in
the tens of thousands.
Most of
the orchid flowers are epiphytes, growing
with their roots not
in soil but instead hanging down tree branches
in the rain forest.
A few
orchids are
parasites; lacking chlorophyll, this
orchids
extract the necessary nutrients from the
organism on which they grow. One Australian
orchid even spends its entire life
underground. Orchids come in every color
except black, and though few have any
fragrance, the ones that do run the
gamut from the scent of chocolate to
that of carrion. Orchid plants have a complex
lifestyle.
Orchids are so unlike other
flowering plants, in fact, they
seem to live in a kind of isolation from
other organisms. Darwin wrote a book on
them--On the various contrivances
whereby orchids are
fertilized by insects, and
effects of crossing.
Orchid Nursery |
Red Orchid |
Pink Orchid |
Darwins book served as a kind of sequel to
his Origin of Species, and was intended
to clarify certain points crucial to the
theory of natural selection.
But only
quite recently--and only because of the
advent of powerful molecular techniques
such as genetic sequencing--have plant
biologists been able to reconstruct the
history of the orchid family to which these
alluring flowers belong.
Darwin argued that
natural selection cannot take place unless
organisms cross with other individuals. The
reason he gave is that the survival of
individuals best adapted to prevailing
ecological conditions--often called "survival of
the fittest"--depends on the existence of a
broad |
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spectrum of
characteristics to meet whatever those
conditions throw at the individuals of a
species.
Sexual
reproduction of plants, with its radical
reshuffling of genes in each new
generation, gives rise to that variety
of orchid plants.
Most plants--particularly the
angiosperms,
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Orchid White and Pink |
Orchid Nursery |
or flowering
plants--possess both male and female
parts, and so they can, in principle,
fertilize themselves.
The fact that they
do not--indeed, that they have evolved a
wide range of strategies for preventing
self-fertilization--seems to support
Darwin's reasoning.
In his book on
orchids he documents the elaborate
frills and furbelows, gimmicks and
traps, that lure and exploit insect
pollinators, thereby ensuring
cross-fertilization.
Darwin's classic
volume thus also lays the foundation for
the study of the coevolution of plants
and animals: how changes in one alter
the other, leading to the ongoing
evolutionary adjustment of both.
The
blossoms of the orchid plant are
simplified in certain respects
but quite complex in others.
Consider the architecture of the
stamen, the flower's male
component, and the pistil, its
female component.
Orchids belong to the
class Liliopsida (informally called
monocots), along with
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rchid Yellow and red spots |
Orchid Orange Color |
Orchid Yellow and red color |
Orchid dark Orange Color |
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grasses and lilies, which both
produce stamens in multiplies of
three. |
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Orchids on the Palm Tree |
But orchid flowers
typically bear just one fertile stamen.
Furthermore, that stamen is fused with the
pistil, forming a bisexual structure called the
column [see illustration on bottom of opposite
page.
Pollen is
produced within the anther at the apex of
the column. Typically, the pollen grains adhere
to one another, forming one or two small masses
attached to a sticky pad--a complex structure
called the pollinarium.
Atop the pollinarium
is the anther cap, a kind of hood that prevents
self-pollination and is easily dislodged by an
insect's body or a hummingbird's bill.
Any visitor that
comes in contact with the pollinarium's sticky
pad ends up conveying the entire structure,
pollen and all, to its next stopover--which may
or may not be another orchid of the same
species.
Because
the pollinarium attaches to any visitor
that dislodges the anther cap, |
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the anther is empty
when the insect or bird flies away. In other words, the
orchid has a one-shot chance of
effectively attaching the pollinarium to
a visiting pollinator, and thence to
another flower. Increasing the odds of
success is the flower's labellum, or
lip--usually the largest, most colorful, most
elaborate petal
Violet and Yellow Orchid |
Yellow and red orchid |
which serves as a landing
platform for insects, and positions the apex of
the column immediately above the potential
pollinator's body. Instead of relying primarily
on fragrance or nectar to attract and reward |
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Red Dyakia Orchid |
pollinators, orchids
generally use color, shape, mimicry, and
overall floral morphology to lure
(though usually not to reward) them. All
this reducing, restructuring, and fusing
of the male and female floral organs,
coupled with a lack of reward for the
pollinators and a single chance of
success, may seem a risky reproductive
strategy--but evidently it works.
Orchids, after all, are one of the most
successful families of plants.
Once pollinated,
the ovary of an orchid
develops into a capsule filled with tens
of thousands of microscopic seeds.
Within each seed is an amorphous embryo
made up of just a few cells; unlike the
embryos of most seed plants, the orchid
embryo is not provisioned with a food
source.
Furthermore, the orchid progeny
are protected from the elements by
nothing more than a paper-thin seed
coat, leaving them vulnerable to damage
and desiccation, and to attack by
microorganisms. But the design has the
great advantage of being
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economical,
enabling the seeds to travel great
distances.
Actually, and counterintuitively the
seed's exposure to microbial attack is
no bad thing. To germinate at all, the
seed must first be invaded by a fungus.
Once the orchid embryo makes a cellular
connection with a fungus, the immature
seedling begins to siphon off essential
nutrients from its fungal host. In other
words, the orchid seedling becomes a
parasite on the fungus. The orchid may
carry on with this living arrangement
until it develops leaves capable of
photosynthesis, making it able to
manufacture food on its own.
Alternatively, the orchid may continue
to feed off its host for the rest of its
life, without ever producing green
chlorophyll. This strategy is called myco-heterotrophism, and orchids are its
most common practitioners. |
Dyakia Orchid |
Yellow and Red Orchid |
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Clearly, orchids are an exceptional
family of plants. Classifying them
within the standard system of taxonomy,
and thereby indicating their closest
relatives, has been a matter of
considerable controversy among
botanists.
Some have focused on the
orchid seed as the basis for
classification, placing Orchidaceae
alongside other mycoheterotrophs. Others
have focused on the flower, and
considered the family closely related to
the lilies. Still others have placed
them in their own unique order,
Orchidales, which just sweeps the
controversy under the rug.
Recently, however, cutting-edge
techniques of molecular biology have
offered an entirely new basis for
classification. The most important of
those techniques is DNA sequencing--the
process of determining the exact order
of the nucleic acids that collectively
constitute the genes comprising the
genome of the plant.
Biologists have
already sequenced the complete genomes
of more than a dozen multicellular
organisms, including mice, rice, and
human beings. But the sequence of even a
small portion of an organism's genome
can help reveal fundamental aspects of
its natural history--the path the
organism took to get to where it is
today.
The genetic approach,
then, is
amplifying the practice of
orchid classification, rooting it in history. Systematics--the
broad investigation into the discovery,
naming, and cataloging of
biodiversity--has become not just a
collector's passion, but a
fundamental pursuit in biology'.
For the
orchid plant systematist, DNA sequences yield
crucial information about the ancestors
and closest living relatives of orchids,
when and where orchids evolved, and why
they came to have such a complex
lifestyle.
Genetic analysis shows that Orchidaceae
is a member of the order Asparagales, to
which the agave, asparagus, hyacinth,
iris, and onion families also belong.
The orchid family, moreover, was the
first of those groups to branch off on
its own. But because orchids have left
almost nothing in the fossil record,
determining a date for their origin has
not been straightforward.
Some biologists, therefore, have turned
to an investigative tool known as a
"molecular clock," whose ticking is
based on the assumption that DNA mutates
at a fairly constant rate. The clock is
usually calibrated by comparing its
(admittedly speculative) readings with
the independently agreed upon dates of
some widely recognized fossils from
various plant or animal families.
Molecular clocks are not without their
critics, but one such clock has enabled
botanists to calculate that orchids
may have branched of prior to 100
million years ago, around the end of the
early Cretaceous epoch--much earlier
than traditionally thought.
One reason that orchid age estimate
seems surprisingly ancient to many
botanists is that most major orchid
groups occur in either the Old World or
the New World, but rarely in both.
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Vanda Orchid
Purple
Vanda Orange
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Orchid flower white violet |
Orchid flower nursery |
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A plant group
native to the continents in one of those
regions, but absent from those in the
other, might be expected to have
established itself more recently than
100 million years ago--that is, after
South America and Africa (which were
once part of the super continent Gondwana)
had fully separated, thereby preventing
further exchanges of organisms between
the two landmasses.
Two other reasons for thinking orchids
are of relatively recent origin are that
most are epiphytes (and thus presumably
arose after the emergence of forests
full of flowering plants), and most
sustain complex relationships with
certain insect groups (bees, for
instance, didn't become pollinators
until the advent of flowering plants).
And sure enough, most
hybrid
popular orchids evolved not so very long
ago. Yet DNA data from several small
groups--particularly the one to which
the genus Vanilla (source of the
much-loved flavoring) belongs--support
the idea that orchids in general are of
ancient origin.
Vanilloid orchids, which encompass some
fifteen genera that form the subfamily Vanilloideae, have always posed an
enigma to orchidologists.
They in
corporate certain advanced
features--some are climbing vines, some
have winged seeds, most have highly
elaborate flowers--as well as features
that usually occur in more primitive
orchids: they are terrestrial, their
pollen grains are not lumped together on
a pollinarium, and the fusion of their
stamens and pistil is less complete than
in most other orchids. DNA sequencing,
in fact, shows that Vanilla and its
close relatives diverged from other
orchid lineages early on. |
Pink Orchid
White Orchid |
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3 Orchids White
Orchid Orange Color full Plant
Orchid White
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Orchid Dark Violet
Orchid White and Violet
Orchid Orange Color
Orchid Dark Yellow
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Furthermore, vanilloid orchids today are
distributed across the tropical belt of
the Southern Hemisphere: Africa, eastern
Australia, the Pacific island of New
Caledonia, South America, and Southeast
Asia (especially Papua New Guinea, but
also Indonesia and Malaysia), all of
which were once part of Gondwana.
Although significant rifting began in
Gondwana about 165 million years ago.
It
was not until about 100 million years
ago that Africa and South America became
distinct continents; Antarctica,
Australia, and New Caledonia, however,
re-roamed in contact until as recently
as 85 to 90 million years ago.
If the
orchid family evolved on Gondwana prior
to 100 million years ago, the ancestors
of the vanilla orchids would have had
plenty of time to spread across the
super continent before it broke apart,
and their family tree should reflect
that historical pattern of continental
breakup.
Indeed, that's precisely what
the DNA data show.
So orchids have been around for a long
time. But the same holds true for
many other families of flowering
plants.
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What
then, has enabled orchids to become
so diverse? Extreme
specialization together with specific
insect pollinators is usually cited as the
primary driving force. And that is
almost certainly an important factor.
But the DNA data suggest an alternative,
though complementary, explanation.
Cattleya Orchid Yellow and
red color |
Pink Orchid glowing |
Biologists often specify the
evolutionary relationships among
organisms via a treelike diagram called
a cladogram. In essence, a cladogram is
a map of history as well as kinship.
Genetic
change takes place through time, and on
the orchid's genetic tree, one of the
most recent (sometimes represented as
one of the shortest) branches includes
more than 85 percent of all orchid
species.
That kind of pattern is generally a sign
that a single momentous event or a
decisive biological innovation has taken
place--say, a drought that led to
desertification, or a petal transformed
into a vessel for nectar.
Such changes
often lead to increased evolutionary
activity and speciation: in effect, an
evolutionary big bang.
The orchid plant systematize seeking to explain
such a pattern would logically look for
the distinguishing features of the
plethora of orchids populating that
single branch of the cladogram.
Could
the branching mark a shift from one kind
of pollinator to another? Does it signal
some innovation in the structure of the
orchid's flower, fruit, leaf, pollen,
seed, or stem? All are
logical possibilities. |
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green color |
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But the DNA evidence--from five of the
orchids' chloroplast genes--actually
points elsewhere. It turns out that the
branching records a divergence between
species that dwell almost exclusively on
the ground (terrestrials) and species
that dwell almost exclusively in trees
(epiphytes). Obviously that's a major
shift, and, not surprisingly, it was
accompanied by changes in orchid
physiology. Stems became specialized for
water storage. Roots developed to absorb
water from the atmosphere, hold it like
a sponge, and resist desiccation. Leaves
learned to perform photosynthesis in
sunny, windy, drying conditions. And so
quite possibly this change in both habit
and habitat--even more than coevolution
with pollinators--drove the evolution of
the biological innovations and the new
orchid lineages.
One mustn't rush to conclusions, though.
A transition from a terrestrial to an
epiphytic lifestyle might have led to an
explosion of diversity in orchid
species, but that doesn't imply the
shift is always strictly a one-way trip,
or that pollinators haven't played a
major role in the evolution of orchids.
Quite the contrary. Several otherwise
epiphytic orchid groups appear to have
descended from the trees back to the
ground ("back" because orchids
originally started out on the ground).
Once again, DNA evidence has helped
resolve the question.
Consider the evolutionarily advanced
group of orchids known as Malaxideae,
which traditionally includes at least
three genera: Oberonia, Malaxis, and
Liparis. All Oberonia species are
epiphytes, whereas all Malaxis species
are terrestrials. Liparis, however,
includes nearly equal numbers of
epiphytes and terrestrials. The
traditional classification of malaxids
is based on the assumption that
epiphytism was its ancestral condition,
and that members of two genera
independently adopted a terrestrial
lifestyle. But now DNA sequences from
both the nucleus and the chloroplasts of
more than fifty malaxid species show
that all the epiphytic species are
derived from a single common ancestor,
and all the terrestrial species are
derived from another. In other words
only one evolutionary event brought
these orchids down from the trees again.
Such new hypotheses about the relations
among species challenge the traditional
basis for classification: the
architecture of the flowers. For
centuries, botanical taxonomists have
focused on reproductive structures, such
as flower parts, fruits, pollen, and
seeds. Their underlying assumption was
that the visible forms of vegetative
structures, such as leaves, roots, and
stems, are subject to considerable
change because of the plant's need to
adapt to particular environments, and
thus those forms are unreliable
indicators of kinship. That process,
called "convergent evolution," is
exemplified in the remarkable
similarities among the thorny, leafless
stems of various unrelated desert plant
families, such as cacti, milkweeds, and
spurges. |
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Orchid Nursery
Yet the DNA data seem to indicate that
orchids--whose flowers readily change
color, form, shape, and size as a result
of the selective pressure of specific
pollinators--disobey that "rule."
Flowers can be misleading. The mode of
growth--whether terrestrial or
epiphytic--and the structure of the
leaves and stems turn out to be the
better indicators of malaxids' (as well
as some other orchids') evolutionary
history.
Biologists generally maintain that
hierarchical classification systems
should be "natural"--that is, based on
evolutionary relations rather than on
some shared attribute such as flower
color, leaf shape, or geography. To some
extent, a plant's name and its placement
in the hierarchy should enable one to
infer part of its evolutionary history.
And as hypotheses about evolutionary
relationships change, so must the names.
Other sources for orchids:
Orchids Basics
Index names
Orchid
Habitats
Darwin and countless other biologists
of
the past made huge strides in
understanding the natural history and
evolution of orchids. Some of their
hypotheses, however, were based on
educated speculation and have quite
recently been shown to be in error. New
genomic data and high-speed computers
have helped contemporary investigators
propose more objective and estable hypotheses than those
put forward by their
predecessors.
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Most of the DNA data support
traditional classifications, but
some--the data on the malaxids,
for instance--do not. From where
I stand, the present century is
an exciting time to be in the
business of botanical sleuthing.
Soon botanists will know a lot
more about the plant kingdom's
most glamorous angiosperms--the
flowers, as Darwin put it,
"universally acknowledged to
rank amongst the most singular
and most modified forms in the
vegetable kingdom."
Author Kenneth M. Cameron COPYRIGHT Natural History
Magazine, Inc. & Gale Group |
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