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From: K.G. GOPALAKRISHNAN <kgopalakrishnan52@yahoo.in>
Bamboo - The Fastest Growing Woody Plants in the World 
From: K.G. GOPALAKRISHNAN <kgopalakrishnan52@yahoo.in>
The World's Fastest Plants
Bunchberry - World's fastest plant explodes with pollen
Cornus canadensis (bunchberry or Canadian dogwood) grow in
dense carpets in the tiaga or boreal forests of the northern
hemisphere. Flowers bloom in late spring and produce small,
edible, red berries during the summer.
Like a medieval catapult, the bunchberry dogwood shoots
pollen grains into the air faster than the Venus flytrap can
snap its jaws shut, giving this launcher the speed record
for plants.
"Most people think of plants as stationary and sedentary," said
Joan Edwards of Williams College . "We were even surprised
how fast this flower opens."
Using high-speed video observations, Edwards and her
colleagues timed the tiny explosions of Cornus Canadensis,
a species of dogwood that covers the ground of spruce-fir
forests from Virginia to Canada . The flower opens its
petals and fires its pollen in less than 0.5 milliseconds.
This discharge is quicker than other speedy organisms:
the Venus flytrap closes in 100 milliseconds; the froghopper
(an insect) leaps in 0.5 to 1.0 milliseconds; the mantis
shrimp (a tiny crustacean) kicks in 2.7 milliseconds.
This shows a flower first closed and then open.
The bar is 0.04 inches (1mm).
Bunchberry flower opening, recorded on video at 10,000
frames per second. Time elapsed is indicated. First frame
shows a closed flower with four petals fused at the tip,
restraining the stamens. Scale bar is 1mm.
Laskowski, A. Acosta, J. Edwards.
Venus Flytrap's Speed Secret Revealed
Closed cilia around the prey
The Venus Flytrap, Dionaea muscipula, is a carnivorous plant
that catches and digests animal prey—mostly insects and
arachnids. Its trapping structure is formed by the terminal
portion of each of the plant's leaves and is triggered by tiny
hairs on their inner surfaces. When an insect or spider crawling
along the leaves contacts a hair, the trap closes if a different
hair is contacted within twenty seconds of the first strike.
The requirement of redundant triggering in this mechanism
serves as a safeguard against a waste of energy in trapping
objects with no nutritional value.
The carnivorous Venus flytrap plant can snap its clamshell
leaves around an insect in less than a second. But how?
Unlike animals, plants have no muscles or brains. And plants
are not known for their ability to move quickly, as a team
of scientists and engineers point out in the Jan. 27 issue of
the journal Nature.
The secret has been revealed: The flytrap's leaves snap from
The secret has been revealed: The flytrap's leaves snap from
convex to concave the same way that a contact lens can flip
inside out, the scientists say.
The team cut up leaves to study their natural curls, and also
painted fluorescent dots on intact leaves to track their
insect-devouring action with high-speed cameras. Like most
lenses, Venus flytrap leaves are doubly curved, that is,
curved in two directions, which allows the leaves to store
elastic energy.
With a contact lens, the two directions are perpendicular
to one another. With a Venus flytrap leaf, they are not.
That property creates an especially rapid elasticity that
causes the leaf to snap even more quickly from
convex to concave.
Venus Flytrap leaf
Bamboo - The Fastest Growing Woody Plants in the World
Bamboo is a group of perennial evergreens in the true grass
family Poaceae, subfamily Bambusoideae, tribe Bambuseae.
Giant bamboos are the largest members of the grass family.
In bamboo, as with other grasses, the internodal regions of
In bamboo, as with other grasses, the internodal regions of
the plant stem are hollow and the vascular bundles in the
cross section are scattered throughout the stem instead
of in a cylindrical arrangement. The dicotyledonous woody
xylem is also absent. The absence of secondary growth wood
causes the stems of monocots, even of palms and large bamboos,
to be columnar rather than tapering.
Bamboos are also the fastest growing woody plants in the
world. They are capable of growing up to 60 centimeters (24 in.)
or more per day due to a unique rhizome-dependent system.
However, this astounding growth rate is highly dependent
on local soil and climatic conditions.
Bamboos are of notable economic and cultural significance in
East Asia and South East Asia where the stems are used
extensively in everyday life as building materials and
as a highly versatile raw product, and the shoots
as a food source.
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