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How do plants attack?
Handle with care
Ouch! How often can you grimace your face if you accidentally prick your fingers by the thorns of the roses? Poor you, if only plants could laugh because of your clumsiness. Even, the Father of Evolution Charles Darwin cannot or didn’t make a chart detailing the “evolution” of plants. Biologists cannot figure out how to conveniently and convincingly arrange an “evolutionary tree” for the plant kingdom. (For more concrete reference, check the book Plant-Environment Interactions for more of your readings.)
Plants, mostly, cannot make a sound of their own without the aid of the air. However, there’s an exception if you can actually witness and hear the sound of a young bamboo growing. You can hear the groaning of growing plant.
Plants have no nerves, but that does not make them “dumb” (This is according to Dr. Richard Yen, a cell biologist, founder of a biotech company and advisor to the West Coast Chinese Christian Conference-www.drrichardyen.org). If we chop off or cut half a tree, it can still survive very well. Try it on animals; it will not work well. Because plants have roots that nourish its growing stage while animals don’t have. Although, its roots are stuck to the ground, it can also move through vines and grow tall.
My first encounter with plant defense was with the makahiya plant. I always poke the leaves and it will close as if sleeping. It is really a shy plant, but later, did I knew that it’s their defense against intruders like me.
You should also be aware of carnivorous plants like the Venue flytrap or pitcher plant. If a plant can eat flies, how “dumb” it can be?
Bracken ferns secrete toxins when chewed by insects (A Natural History of Ferns by Robbin C. Moran, 2004). This fern produces hydrogen cyanide immediately after an insect bites into it. They are also loaded with ecdysones, hormones that promote molting. One meal and the insect will soon shed its exoskeleton and die! Imagine if we have this kind of hormone?! It’s more dangerous than a predator!
With the progress in molecular biology, they discovered that ferns have self-defense mechanism. Although plants have no nerves, they “know” they are being attacked.
Way back 2006, molecular biologists counted 15 plants that are known to “call for help.” Corns call for help when attacked by caterpillar. These plants release a chemical to attract wasps which will come and paralyze, but not kill the diner. The wasp will then deposit eggs inside the caterpillar which will be eaten from inside out when the eggs hatch. Scientists in Japan confirmed that corns release more wasp-attracting chemicals during daytime.
The silence of the plants mean something. It can be danger to those who are abusing them.