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A Plant That Can Smell
BlueCup writes "The question of how a dodder finds a host plant has puzzled researchers. Many thought it simply grew in a random direction, with discovery of a plant to attack being a chance encounter. But the researchers led by Consuelo M. De Moraes found that if they placed tomato plants near a germinating dodder, the parasite headed for the tomato 80 percent of the time. And when they put scent chemicals from a tomato on rubber, 73 percent of the dodder seedlings headed that way. Turns out, it sniffs out it's prey."
But the researchers led by Consuelo M. De Moraes found that if they placed tomato plants near a germinating dodder, the parasite headed for the tomato 80 percent of the time. And when they put scent chemicals from a tomato on rubber, 73 percent of the dodder seedlings headed that way. Turns out, it sniffs out it's prey.
See, now I would have thought that it would have been the tomatoes that made the first strike...
The theory of relativity doesn't work right in Arkansas.
A dodder is also known as a Cuscuta.
Be relentless!
Somehow I think that plant pathologists have probably noticed this for decades. It a pretty useful lab plant for moving pathogens between plants in interesting ways. Dodder is grown in plant path greenhouses commonly and usually near host plants.
I can't find anything on google about it, but there was a tale of an experiment where a man went into a greenhouse and hacked up all the plants.
A bunch of scientific equipment was setup to measure plants behaviour/electrical impulses.
They then had 10 people walk through the room and when the man who hacked the plants entered the room the plants sent off strong/furious signals.
I always wondered if this was a true experiment or urban legend...but with this species of plants sensing different kinds of chemicals, it just might have been real.
Yo Grark
Canadian Bred with American Buttering
My dodder has no nose.
How does it smell?
Terrible!
"I've got more toys than Teruhisa Kitahara."
Nothing new here, as apparently, this one smells quite a lot.
If the genetic engineering wizards could find out how to transplant this characteristic to, say, aquatic plants, perhaps they could modify them to attack the destructive zebra mussels that are such a major problem in the Great Lakes, or to control problem plants such as hydrilla verticillata.
It's an fun thought, even if I lack the background to evaluate its feasibility.
A truly excellent pizza parlor is a delight unto the heavens. Treasure the sauce and the toppings!
I was hiking with my parents in the Shining Rock Wildnerness, an area in western North Carolina. Part of the wilderness was burned out sometime in the 1920's and the burn formed a long lasting grassland along several peaks. We hiked it sometime in the early 90's and it was the first time I saw dodder. It was this strange mat of oranged colored leafless vines, much like this growing on a particularly plant (very similar to what is in the photograph, I believe). The strange thing is that we had hiked this trail over many years and had never seen this before. So we wondered at first if it were some new invasive species from elsewhere. Turns out that this was native to the area, but for whatever reason it never had grown this prolifically before. Definitely one of the strangest plants I've ever run across.
The Flying Speghetti Monster is seeking out holy tomato sauce! I believe I belieeeeeve!
Table-ized A.I.
Smell is not just chemoattraction. Plants also grow in the direction of sunlight, does that mean they can see? They grow away from gravity, does that mean they can feel?
Um, wouldn't this be "while my guitar gently creeps"?
Table-ized A.I.
http://www.npr.org/templates/story/story.php?story Id=6160709
The Acacia tree is sensitive to chemicals given off by other Acacia trees when they are damaged. It responds by increasing it's Tannin production in order to help ward off possible predators. I'm not sure of what the scientific definition of smell is, but I'd probably define it as "the ability to sense the existance of airborne chemicals".
God was my co-pilot, but then we crashed and I was forced to eat him.
Even *single-cell* flagellates have what can be considered a rusimentary sense of smell, and the capability of changing their locomotion in order to lead them to food. That sort of ability is present all the way up through the multicellular ladder, and "smell" (or response to airborne chemical signals) have been well-known for quite some time in plants.
Frankly, I'm susprised that they didn't start out with an assumption that smell was involved.
steve
Oh, you're not stuck, you're just unable to let go of the onion rings.
Smell isn't anything more than detecting fairly dilute chemicals
in the air. The fact that some species of plant have evolved to
perform very specific kinds of chemical detection to ensure their
survival doesn't seem surprising to me. Plants grow towards the
light - why not towards other things that are essential for their
survival.
They don't mention what their sample size is, i.e., is it 100 plants?
I can toss a coin 4 times, and let's say I get tails 3 times. Simultaneously, if I was tossing another coin nearby, and happen to get 3 tails out of 4 again on it too, can I conclude that the second coin supernaturally knew what the result on the other one was? BTW, the probability that the above happens is 1/16. Also, I can repeat this experiment many times to get this case.
Obviously, those researchers are smart enough. My question is: how can they write such a big article without mentioning about the sample size?
I got dodder in my garden from a basil plant I bought at a local nursery. That is one vicious weed. It's a parasitic rootless vine, hard to imagine if you've never seen it.
In group behavior: 'because they're evil/morons/sheep/crazy' is not 'insightful' it's 'oversimplified'
Right "its", wrong "prey."
Eating is so passe. Cut out the middle man, learn to photosynthesize!
I don't care if it's 90,000 hectares. That lake was not my doing.
Hmmm, nice that the article doesn't mention the actual author of the paper (published in Science). Also not surprisingly, the actual paper doesn't talk about 'smell'. Oh and for the person going on about sample size, of course the paper gives sample sizes.
6 4.pdf
Here's the abstract:
Volatile Chemical Cues Guide Host Location and Host Selection by Parasitic Plants
Justin B. Runyon, Mark C. Mescher, Consuelo M. De Moraes*
The importance of plant volatiles in mediating interactions between plant species is much debated. Here, we demonstrate that the parasitic plant Cuscuta pentagona (dodder) uses volatile cues for host location. Cuscuta pentagona seedlings exhibit directed growth toward nearby tomato plants (Lycopersicon esculentum) and toward extracted tomato-plant volatiles presented in the absence of other cues. Impatiens (Impatiens wallerana) and wheat plants (Triticum aestivum) also elicit directed growth. Moreover, seedlings can distinguish tomato and wheat volatiles and preferentially grow toward the former. Several individual compounds from tomato and wheat elicit directed growth by C. pentagona, whereas one compound from wheat is repellent. These findings provide compelling evidence that volatiles mediate important ecological interactions among plant species.
And here's the actual paper for those with access to Science articles:
http://www.sciencemag.org/cgi/reprint/313/5795/19
Si hoc legere scis nimium eruditionis habes.
Person 1: My Amorphophallus titanum has no nose!
Person 2: How does it smell?
Person 3: Fucking awful.
Task Mangler
Plants react to stimuli - that's well-known. They grow in the direction of light, the fruits ripen when there is ethylene in the air. Hell - you even have insect-trapping plants..
:)
So, if there are unique chemicals that the prey species give off, there is no surprise the doddler can detect them and react to them. Cool that scientists did the study and found this example, though
Stop the brainwash
Actually, IIRC, plants don't actually follow strong light. Light inhibits growth strangely enough. So plants don't follow the sun, it's just that the lighted side of the plant grows at a slower rate than the darker side, thus causing the plant to curve toward the light. At least, that's how I've always understood it.
While I might agree that plant's "grow" at a slower rate in more intense sunlight, I don't believe it's proper to say that sunlight inhibits growth. What happens is that when a plant is in sufficient sunlight, it can devote its nutrients to growing heartier rather than "bigger." Plants in sufficient sunlight tend to be short, but also have thicker stalks and fuller (though fewer) leaves. Plants in low light grow taller and lankier, because they are a) trying to maximize their surface area to most efficiently absorb as much sunlight as possible, both through sheer size and by producing more leaves, and b) potentially grow taller than whatever is obstructing their ability to get to the light (think of a bunch of plants all in close proximity on the ground. The taller the plant, the less likely it is to be oovered up by another plant. So if a plant is not getting enough sunlight, it's possibly because all the other plants around it are taller than it. Therefore the best response is to get even taller still).
I don't have any studies, but I believe I've seen plants that shifted significantly after a change in the direction of the source of light (such as if you turn the plant 180 degrees after being in front of a window), a shift that occurred much too quickly to be explained away by the speed at which different sides of the plant grew.
Ok flame-proof suit on, but "it's" is short for either "it is" or "it has". In this case the apostrophe isn't needed to denote ownership any more than you need an apostrophe in the words 'his' or 'hers'. More info at the Apostrophe Protection Society.
GodboltBlog
The shocking revelation is that 7% of the dodders weren't fooled by the simulated tomato smell. Those dodders are seeing the fake tomato patches as a trick. Those are the dodders to watch.
--
make install -not war
When one smells aren't they absorbing tiny particles of whatever the "object" that is being "smelled" is releasing? Couldn't the plant be reacting to particles of what is it's food that happens to be floating in the air from a particular direction?