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misc Scientific Observations of Environmental Stress on Pepper Varieties

Does your wife screaming at you for being intoxicated in the backyard growing area count as environmental stress? Because my chilis are always hot AF.
 
Seriously, if you grow outdoors outside of an equatorial climate then every second of every day is "environmental stress". Wind starts, sun goes behind cloud, iceballs fall from the sky, seagulls invade crow territory and start a several-hour long aerial war so loud that people can't even talk, ambulance sirens wail, the fucking ice cream truck cruises the neighborhood for hours on end with the megaphone on full-blast. I'm stressed and need a drink, so my plants must, too, right? 
 
We've had repeated higher than normal UV levels this spring-summer. Normally, I only get sunburns but this year for the first time in my life I am actually brown instead of red. But that might be because I've eaten a lot more guacamole this year than average. That's really just as good of a guessplanation as anything else. I don't use sunblock or tanning lotions - just put on a shirt when my skin starts to feel hot. Scientific observation, right?
 
Hey Podz,
You forgot neighbors shooting off fireworks at 1:00 am during the week[emoji16]. Neighbors shooting skeet and hitting your house with shot. : more stress factors [emoji16]


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Karpasruuti said:
Better to stress very hot and super hot chilies. What about daily stress? Watering every day but giving significantly less water than normally. There seems to have some formula. My chilies has always been very hot it may be that I usually water them when they doing sad face. More torture  :evil:
 
No, it was just another inconclusive study.  Some results said yes, some said no.  All in all, it was just another study that somebody grew a bunch of plants in the same place, and only altered the watering to try to produce a hotter chile. (to limited effect)
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Again, there are other "studies" published on this forum that suggest the exact opposite - that a substantive increase in capsaicin through stress and depravation, is only achieved in the lower scoville varieties.
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When two studies appear to contradict, that means that you have a paradox to address.  It doesn't mean that one or both are correct or incorrect.  It certainly doesn't mean that we draw conclusions, unless those conclusions are consistently repeatable in the conditions that we've allowed for.  And even then, it's probably more of a matter of providing a baseline, than making absolute determinations.
 
SFGATE-How to Grow Hotter Jalapeños  

'Stress the pepper plants once they blossom and start producing peppers. The more stressed the plant is, the more capsaicin will grow inside the peppers, and this is the chemical that gives jalapenos heat. Allow the soil to dry out until the plant's leaves start to shrivel, then give the plant a good soaking. Repeat this process throughout the growing season to create the hottest jalapenos.'
 
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Regarding the SFGate article, if you want hot peppers, then why are you growing jalapenos?  The article should be - Grow pepper varieties other than jalapenos if you want heat.  
Also:   "If you see a spot of red or orange on a jalapeno, harvest it right away as it's reached the peak of ripeness." - Uhhhh, not if you want red jalapenos.
And:  "Always wear plastic gloves when picking jalapenos to avoid getting dangerous amounts of heat on your hands."  - Dangerous????
I read SFGate stuff sometimes, but they are kind of like a wiki-light.  Enough to give you a general idea about a topic, but not really in-depth analysis by industry professionals. It is a lot of "authors" just wanting to get their name in print with info lifted off of other websites and vaguely regurgitated.  About any one of us on here could do that (except maybe for TB, editors would not like his writing style, or his youtube links, or thumb ring pics). 
 
I also gotta agree with solid7 on this.  I do science for a living (if you can call it that these days).  Most of these published findings are kind of - meh.  There is a bit of - could be this, could be that.  A lot of not really much.  If there was something to it, there would be food production studies.  That is where the $$ is, so that is where the science would be.  Hey, I like looking at these little studies and doing some of my own also.  Have not had an eureka myself.  But, maybe, someday.  
But, I have learned a lot of what not to do.  And that is not nothing.
 
fishhead said:
Regarding the SFGate article, if you want hot peppers, then why are you growing jalapenos?  The article should be - Grow pepper varieties other than jalapenos if you want heat.  
Also:   "If you see a spot of red or orange on a jalapeno, harvest it right away as it's reached the peak of ripeness." - Uhhhh, not if you want red jalapenos.
And:  "Always wear plastic gloves when picking jalapenos to avoid getting dangerous amounts of heat on your hands."  - Dangerous????
I read SFGate stuff sometimes, but they are kind of like a wiki-light.  Enough to give you a general idea about a topic, but not really in-depth analysis by industry professionals. It is a lot of "authors" just wanting to get their name in print with info lifted off of other websites and vaguely regurgitated.  About any one of us on here could do that (except maybe for TB, editors would not like his writing style, or his youtube links, or thumb ring pics). 
 
I also gotta agree with solid7 on this.  I do science for a living (if you can call it that these days).  Most of these published findings are kind of - meh.  There is a bit of - could be this, could be that.  A lot of not really much.  If there was something to it, there would be food production studies.  That is where the $$ is, so that is where the science would be.  Hey, I like looking at these little studies and doing some of my own also.  Have not had an eureka myself.  But, maybe, someday.  
But, I have learned a lot of what not to do.  And that is not nothing.
 
So you do science for money? Just wonderin'.......
 
 
EDIT: Found another!


The pungency of chili peppers is conferred by compounds called capsaicinoids that are produced only in the fruits of the Capsicum genus. Accumulation of capsaicinoids in these fruits may be affected by environmental conditions such as water and nutrient stresses, although these effects may vary even among genotypes within a species. The Habanero pepper (Capsicum chinense Jacq.), grown in the Yucatán, is in especially high demand as a result of its unique flavor, aroma, and pungency and is the second most important commercial crop in the state after the tomato. Although the Habanero pepper is a significant economic resource for the region, few studies have investigated the effects of abiotic stresses on capsaicinoid production. In this study, the effects of water stress on plant growth, capsaicinoid accumulation, and capsaicin synthase activity were evaluated. Habanero pepper plants under water stress had a lower height, root dry weight, and root/shoot relation than control plants, which were irrigated daily. However, fruit growth and production were unaffected by water stress. Capsaicin and dihydrocapsaicin concentrations increased in fruits of stressed plants compared with control plants, and this effect was correlated with fruit age. However, capsaicin synthase activity was reduced in response to water stress, and this effect depended on both stress severity and fruit age. These results provide new information on the regulation of capsaicinoid metabolism in response to abiotic stress from the fruit of a highly pungent chili pepper.
 
 
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ahayastani said:
 
That aberration derives from a capitalistic viewpoint, which decides that science has to be profitable.
 
Nonsense.  If you don't want science to be profitable, you go to work for the government.  There are plenty of places in the US that are happy to abuse your intellect and potential with low pay and long hours, if you just know where to look.
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 We're just lucky enough to live in a place where our occupations and endeavors CAN be profitable.  Don't be a hater.
 
podz said:
The earth is flat and vaccinations will kill you. Jerking off will make you go blind, too. Go ahead and underwater your plants if it makes you feel better.
 
I water my plants before they wilt and they also get rained on quite often. They produce heat on my scientifically observant tongue equivalent to any other source I've ever tried.
 
Exactly.  I withheld my response previously, because... just because.  But if you believe that under-watering your plants makes the fruit hotter, then it does.  Even a psychological effect is a net win.
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Otherwise, we are just guessing, because lots of things say lots of stuff, and nobody really cares to settle it, definitively.  Or they'd undertake the unprofitable task of doing the science.  Those who make their incomes from the subject, do their own research, on their own varieties, in their own areas.  And that's EXACTLY where the science is applicable.  But until I see someone doing a multi-country, multi-region experiment, I just regard all of this as anecdotal, and choose instead, to aim for optimal plant growth. 
 

Have at it boyz!

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GROWTH, QUALITY AND CAPSAICIN CONCENTRATION OF HOT PEPPER (CAPSICUM ANNUUM) UNDER DROUGHT CONDITIONS
 
 
I'm sheltering in place so I don't have to wear a mask & run into......
 

solid7 said:
Then, the social media shaming, which breeds the stupid contemptuous responses.  In the end, nobody's mind was changed, and lots of people are ad lib-ing some very bad behavior. In the end, it's just going to create more militancy vs apathy.
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Right now, I wish there were also a standing order that allows an individual so slap the shit right out of anyone invading personal space (including spitting), or assuming the role of vigilante activist within 20 feet.  At least make this entertaining.
 
The_NorthEast_ChileMan said:
 

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I'm sheltering in place so I don't have to wear a mask & run into......
 
Is it just me, or does anyone else understand where this person is going with this topic?  If I'm unintentionally provoking a special needs person, would someone please PM me, and politely let me know, so that I can course correct?
 
The_NorthEast_ChileMan said:
 

Have at it boyz!

 ​
GROWTH, QUALITY AND CAPSAICIN CONCENTRATION OF HOT PEPPER (CAPSICUM ANNUUM) UNDER DROUGHT CONDITIONS
 
 
I'm sheltering in place so I don't have to wear a mask & run into......
 

 
 
Interesting article you found there, NECM. I told my wife earlier today that I had the impression my peppers in Mexico were more pungent and sweeter compared to Europe (same cultivars; Mexican plants grown from my EU seeds). And yes, I'm chronically under-watering my plants :whistle:
 
ahayastani said:
 
I told my wife earlier today that I had the impression my peppers in Mexico were more pungent and sweeter compared to Europe (same cultivars; Mexican plants grown from my EU seeds). And yes, I'm chronically under-watering my plants :whistle:
 
We see differences all the time in the same foods, grown in different places.  Differences in structure, yield, size, carbohydrate content, etc, etc, etc.  That's why it's folly to relegate a discussion like this to a single variable.  So many things can have an effect on so many other parameters.
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Growing conditions can definitely produce differences.  I noticed this first, in earnest, when doing hydroponic grows.  The methods that produced crops the fastest, often were the most unsatisfying, in terms of actual flavor, to me.  Same seed stock in conventional containers, produced a phenomenally better result.
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I doubt my Florida grown rocotos even hold a comparison to the same grown in the highlands of Peru.
 
NECM
"So you do science for money? Just wonderin'......."

Yes, I "do" science as an occupation. Yes, I earn a salary for performing studies based on collecting and analyzing data (not subjective). Not sure where you are going with that....

solid7, I want to slightly disagree with you comment "I just regard all of this as anecdotal, and choose instead, to aim for optimal plant growth. " Who cares about plant growth? Replace that with plant production. Decades ago midwest farmers were stoked with 14'tall corn plants that produced a healthy ear. Fast forward to genetics/hybrids that grew 8' stalks and 2 jumbo ears, and 99.9% have never looked back.

I don't really have a dog in this fight, I just want to raise a lot of good, tasty, productive peppers. If I want something hotter, I'll plant a hotter variety.

A point that I'd like to raise with these outlined studies are the control groups. Generally they use daily watering. Overwatering can be a form of stress, just as under watering can be. So, these studies have not laid out that theie controls are indeed optimally watered plants. So maybe a better (although probably anecdotal) result could be that potentially overwatered plants produce lower levels of capsaicin.
 
So let me start by saying, I come from a long line of those midwest farmers.  I completely understand your comment.
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I'm not taking anything away from it, but I'll clarify my own.  When I say "optimize plant growth", I am simply talking about getting the best out of your plant.  We all have constraints.  As hobby growers, most of our constraints don't line up with those of commercial growers.  Most of us don't optimize our costs, our times, our harvest methods, etc, as a commercial farmer would.  And, as hobby growers, most of us think with our taste buds, or our itch to grow, rather than outright production.  That leads to a whole lot of us, growing a whole lot of things, that are well outside their "sweet spot".  Of course, since you mentioned it, you're well familiar with the rows of corn that have their 4 or 5 digit hybrid number, at the end of the test patch.  Those hybrids having been selected for tests under specific conditions, in specific regions.  That's the kind of science that we just don't have the benefit of.
 
Your point is well taken, when ag is the driver. But when we talk about growing as a hobby, most of us don't have enough life in us to consume the amount of science that is behind even a single year's grow in a typical agricultural operation.  When I was on the farm, we didn't figure anything out for ourselves.  We relied on our extension office for extensive soil testing, emerging trends, application times, rates, etc.  They have the tools, tech, and access to information.  On top of that, they're pretty damned smart, too.
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So "anecdotal" is strictly from the perspective of a hobbyist trying to consume ag research.  I will consider the information and methods, but I will not consider it authoritative for the backyard.  I'm also guilty of not selecting varieties for pure production, so my advice to any hobby growers - especially new ones - is always the same: Learn do the simple stuff really well.  Grow the best plants that you can, with the minimum of invested effort.
 
I would also argue, that short of selecting specific varieties, logically, optimal production follows optimal growth.  That, in and of itself, is a very nuanced discussion - but I will abide by the more simplistic variant, for now.
 
My apologies for carrying this over 3 posts.  Forum has suddenly become intolerant of long-windedness. (or else something just wasn't working)
 
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