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misc Scientific Observations of Environmental Stress on Pepper Varieties

I'm not a scientist but I do have my intuitions.
 
My armchair theory regarding what causes heat variation is that plants are trying to protect themselves from certain types of non-beneficial animals (the ones who have capsaicin receptors). Those with capsaicin receptors that chomp off a branch, for example, would leave behind a specific enzyme that the plant recognizes, then the plant ramps up capsaicin production to assist in warding off future attacks. But a bird, upon which chiles rely to spread their seed, would not trigger the response. Furthermore, if the plants are in the ground then they send pre-warnings to their cousins in the form of electrical signals over the underground mycorhizzal network. A container garden, like so many of us have, would not support signal transmission at all so the results may be only visible in those specific plants that were attacked by certain predators.
 
Plants sending warning signals about predators over mycorhizzal networks is not new science. But now it has been definitively detected in the Solonaceae family, which includes chiles, tomatoes, etc.
 
https://phys.org/news/2020-07-electrical-tomato.html
 
I now envision forum members strategically biting branches off of their plants.
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Should the edges be left rough, and some bits left dangling?
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This might also make a new case for that copper mesh that I was going to wrap the cloth pots in this season.
 
solid7 said:
I now envision forum members strategically biting branches off of their plants.
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Should the edges be left rough, and some bits left dangling?
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This might also make a new case for that copper mesh that I was going to wrap the cloth pots in this season.
 
I think we need a new forum section for videos :-)
 
podz said:
I'm not a scientist but I do have my intuitions.
 
My armchair theory regarding what causes heat variation is that plants are trying to protect themselves from certain types of non-beneficial animals (the ones who have capsaicin receptors). Those with capsaicin receptors that chomp off a branch, for example, would leave behind a specific enzyme that the plant recognizes, then the plant ramps up capsaicin production to assist in warding off future attacks. But a bird, upon which chiles rely to spread their seed, would not trigger the response. Furthermore, if the plants are in the ground then they send pre-warnings to their cousins in the form of electrical signals over the underground mycorhizzal network. A container garden, like so many of us have, would not support signal transmission at all so the results may be only visible in those specific plants that were attacked by certain predators.
 
Plants sending warning signals about predators over mycorhizzal networks is not new science. But now it has been definitively detected in the Solonaceae family, which includes chiles, tomatoes, etc.
 
https://phys.org/news/2020-07-electrical-tomato.html
More likely to be protecting their seeds from smaller predators,like Fusaria,not herbivores. Plants would evolve spines or toxins to deter the larger animals.
 
Pr0digal_son said:
More likely to be protecting their seeds from smaller predators,like Fusaria,not herbivores. Plants would evolve spines or toxins to deter the larger animals.
 
30 minutes of googling and reading leads to an understanding that capsaicin can be acutely, subacutely and even chronically toxic to a good number of creatures, even found to be neurotoxic to mammals (depending on the dose and administration).
 
Anyhow, IMO predator control is a readily plausible explanation for variation in capsaicin levels.
 
 
https://pubmed.ncbi.nlm.nih.gov/3310520/
 
http://npic.orst.edu/factsheets/archive/Capsaicintech.html
 
https://ec.europa.eu/food/sites/food/files/safety/docs/fs_food-improvement-agents_flavourings-out120.pdf
 
Sola dosis facit venenum. And, of course, also the way it is administered is an important factor. In the following image, capsaicine is administered by smoke :) The olden Aztec days, when the parents had more choices and liberties in the ways they were allowed to punish their children :) I regularly toss chiles in a sauce pan and won't feel a thing, while my wife in the neighbouring room begins a drama about she's going to die... Variation in the population...
 
ans_135_01_2.jpg

 
There really is a lot of recent information available on capsaicin. The receptor involved (TRPV1) is an interesting target for i.a. the pharmaceutical industry.
 
Just one example: Understand spiciness: mechanism of TRPV1 channel activation by capsaicin
 
podz said:
30 minutes of googling and reading leads to an understanding that capsaicin can be acutely, subacutely and even chronically toxic to a good number of creatures, even found to be neurotoxic to mammals (depending on the dose and administration).
 
Anyhow, IMO predator control is a readily plausible explanation for variation in capsaicin levels.
 
 
https://pubmed.ncbi.nlm.nih.gov/3310520/
 
http://npic.orst.edu/factsheets/archive/Capsaicintech.html
 
https://ec.europa.eu/food/sites/food/files/safety/docs/fs_food-improvement-agents_flavourings-out120.pdf
The primary function of fruit is to attract frugivores. We are taught that in elementary school in the USA. If you don't believe that,you are in an extremely small minority.

This is a clever clade that uses birds to get the job done. But that isn't always the case. There are many species that ripen yellow and green in the wild,even species without heat. They are not attractive to birds.

In South America,C.praetermissum ripen red and they are spread great distances but there are not large populations,just sporadic ones because they are dispersed via birds. The species that don't ripen red have very small and isolated populations because they rely on small mammals who do not travel far.

Whatever humans have done to these plants over the last 7 or 8000 years is another story that we can talk about,but these plants evolved with low heat or no heat,and even some with declining capsaicinoids upon ripening.

Zero minutes of googling there. :)
 
Pr0digal_son said:
The primary function of fruit is to attract frugivores. We are taught that in elementary school in the USA. If you don't believe that,you are in an extremely small minority.
 
I have to claim to be in this extremely small minority.  I was very plainly taught that the primary function of fruit, is to house the seed of the plant (which is the main differentiation between a true "fruit" and a vegetable).  In fact, I've actually never been taught that this (attraction) is even a secondary function of fruit.  (although I'm also not disputing that it may indeed, be factual)
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I think you may be giving the US public schools a little more credit than they're due.
 
solid7 said:
I have to claim to be in this extremely small minority.  I was very plainly taught that the primary function of fruit, is to house the seed of the plant (which is the main differentiation between a true "fruit" and a vegetable).  In fact, I've actually never been taught that this (attraction) is even a secondary function of fruit.  (although I'm also not disputing that it may indeed, be factual)
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I think you may be giving the US public schools a little more credit than they're due.
To attract animals for seed dispersal.

Edit: They 100% do not fruit to deter animals from spreading their seeds.
 
Pr0digal_son said:
To attract animals for seed dispersal.
 
I'm not suggesting that you're wrong.  I'm just pointing out that this isn't actually what's necessarily taught.  Clearly, we know that some plant and animal species have a particular symbiosis.  I'm just saying that I don't hold it against anyone for not identifying this as the primary objective, from the point of view of primary education.
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I'm in a different field of sciences. I've always had some troubling question marks over evolutionary science.  Before you go thinking that I'm saying something different, I'm not advocating creationism, or alien terraforming, or anything else.  I'm just suggesting that there seems to be a shocking lack of explanation, with regards to the catalysts of evolutionary processes.  I take particular interest in articles like the ones that podz posted earlier, because for any thinking person, evolution can't happen in a vacuum.  There has to be something going on, whether it's sentient-like, or autonomously reactive bioprocesses.  It's a fascinating discussion - but tell me WHY, HOW, WHEN...  Show me repeatably.
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Math is so much more satisfying that the natural sciences. :)
 
solid7 said:
I'm not suggesting that you're wrong.  I'm just pointing out that this isn't actually what's necessarily taught.  Clearly, we know that some plant and animal species have a particular symbiosis.  I'm just saying that I don't hold it against anyone for not identifying this as the primary objective, from the point of view of primary education.
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I'm in a different field of sciences. I've always had some troubling question marks over evolutionary science.  Before you go thinking that I'm saying something different, I'm not advocating creationism, or alien terraforming, or anything else.  I'm just suggesting that there seems to be a shocking lack of explanation, with regards to the catalysts of evolutionary processes.  I take particular interest in articles like the ones that podz posted earlier, because for any thinking person, evolution can't happen in a vacuum.  There has to be something going on, whether it's sentient-like, or autonomously reactive bioprocesses.  It's a fascinating discussion - but tell me WHY, HOW, WHEN...  Show me repeatably.
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Math is so much more satisfying that the natural sciences. :)
It's fine if you think this is all a simulation. I won't judge you. :)


I'm fine with Podz's self-admitted half baked theory. I just injected something plain and reasonable. That is how evoution rolls for the majority of the time. Especially in this very basic and boring genera. He came back and doubled down on his theory that goes against basic science. Plants use animals to disperse seeds.

He did mention Solanaceae and more specifically,Solanums. Now there are some species in there that take a heavy metal approach to protecting themselves with their spines and noxious fruits and leaves.

Anyway,I've dragged this topic way off course. Cheers!
 
Ha!  Simulation.  I can definitely model complex n-dimensional shapes and their movements, expressed as quaternions.  Past that, I'm sure that simulation is not a very satisfying answer to all of our questions.
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I don't think you dragged this off-topic at all, actually. In fact, short of these types of interactions, I'm not sure that it was really  going anywhere at all.
 
Pr0digal_son said:
It's fine if you think this is all a simulation. I won't judge you. :)


I'm fine with Podz's self-admitted half baked theory. I just injected something plain and reasonable. That is how evoution rolls for the majority of the time. Especially in this very basic and boring genera. He came back and doubled down on his theory that goes against basic science. Plants use animals to disperse seeds.

He did mention Solanaceae and more specifically,Solanums. Now there are some species in there that take a heavy metal approach to protecting themselves with their spines and noxious fruits and leaves.

Anyway,I've dragged this topic way off course. Cheers!

Like I said, I'm not a scientist. My mind with it's intuitive skills, develops a clear and confident vision, which I then set out to execute, aiming to better the lives of others.

Clear and confident vision equals doubling down from some perspectives, I'm fine with that, too!

Or like Elton John put it - you will need to stretch your mind to get my drift:

"I wonder if those changes
Have left a scar on you
Like all the burning hoops of fire
That you and I passed through

You're a bluebird on a telegraph line
I hope you're happy now
While if the wind of change comes down your way girl
You'll make it back somehow"
 
Karpasruuti said:
Rats like or not hate capsaicins. But it would be defense against some bugs and fungys.
 
It's been my general experience that most bugs aren't really deterred at all by capsaicins.  In fact, some bugs are known to make homes in pods that have been chewed open by other bugs or birds.  Can't really speak to the fungi, because I don't have too bad of a problem with that. (I suspect my use of Neem helps that)
 
solid7 said:
 
It's been my general experience that most bugs aren't really deterred at all by capsaicins.  In fact, some bugs are known to make homes in pods that have been chewed open by other bugs or birds.  Can't really speak to the fungi, because I don't have too bad of a problem with that. (I suspect my use of Neem helps that)
There is always expections among of them. Most bugs harm leaves or roots and mammals usually do not eat chilies. It may be that capsaicinoids do cell stress of fungus. 
 
https://biology.stackexchange.com/questions/55009/why-does-capsaicin-irritate-mammals-and-also-kill-fungi-are-the-two-related
 
It seems clear enough that limiting factors play a major role in capsaicin production, accumulation, increase and variation.

If limiting factors are sufficient then stress can increase capsaicin insofar as the genetics allows. If the stress affects a limiting factor involved in the enzymatic pathways then logically there would be less capsaicin. If all factors are sufficient except for N, it makes sense that N would increase capsaicin. If an increase in N results in another limiting factor for capsaicin production being reduced it makes sense that N would cause less capsaicin to accumulate.

The biodiversity in Capsicum is considerable and it makes sense that from a superficial perspective there would appear to be conflicting information because generalizations are overly simplistic and many factors come into play.

Each plant and situation is unique and the plants don't care what we think or what our opinion is. People often confuse knowing something with believing it... suspecting something and creating a null hypotheses and trying to prove it wrong is so much more fun and rewarding than making the mistake of assuming that we know something we actually only believe.

Only fools deal in certainty... the wise deal in probability and there's always going to be a plant out there that just doesn't care about the rules we believe govern it.

Well... that's my suspicion at least.
I am aware of numerous examples where the truth is that we are right to
be confused and we don't have neat little packaged answers.

That works for scientists but not for salespeople.
 
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