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Plant Melatonin: Supercharge Roots and Stress Tolerance in Hydroponics · Hydroponics Daily

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  Hello there and welcome back to
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  Hydroponics Daily, your go-to podcast for everything soilless cultivation.
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  I'm your host, Dr. Russell Sharp, the founder of Eutrema Limited.
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  And today I wanted to talk about a human hormone that helps with stress,
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  but has also been found to occur in plants.
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  And that is melatonin. It's a natural compound and it's produced by various
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  organisms, including bacteria and humans.
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  And you will have heard about it because it plays
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  a role in circadian rhythms
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  your sleep and wake cycle and often
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  often it's talked about in relation to human
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  stress and blood pressure and things like this and it's also but it's also a
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  powerful antioxidant and the same functions that happen in humans it also has
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  a role in in plants So it's produced naturally,
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  and it's a small molecule created from an amino acid called tryptophan.
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  And in plants, it's a signaling molecule, but not a hormone as such,
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  antioxidant and regulator of growth and stress responses.
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  So three times more antioxidant active than, say, vitamin E,
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  which is a very common antioxidant.
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  And it scavenges reactive oxygen species and deactivates them so they can't
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  damage chloroplasts, mitochondria and other cellular organelles and things like this.
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  So it regulates the stress responses and the responses to various chemical hormones
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  like ABA, salicylic acid and ethylene.
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  And so it's thought to be very important with cell elongation and root growth
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  as well and shoot development.
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  And it coordinates the response to photoperiod, the day length and the circadian clock.
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  So very much in relation to, it's very similar into what it does in humans.
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  And you can apply it as a as
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  a spray or in solution and often
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  it's applied to the root zone or as a foliar spray
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  or the seeds as a priming and
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  it's recently research has expanded into hydroponic systems because
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  we can do precise dosing in hydroponic systems if you
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  add melatonin to hydroponic solutions it's going to be in the micromole to
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  millimole concentrations if you don't know what that is go and have a
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  look at that so if you see a sign that looks like a funny shaped
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  u and a capital m that's a micromole you need
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  to know what that is if you're going to dose it correctly you can
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  do sprays root zone treatments or seed priming as i said and
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  the things you're going to be looking for enhanced root growth
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  so really a really good root stimulant stress protection so
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  really high light levels or unstable environments
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  this would be a good one perhaps yield increases
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  but these will be by better stress tolerance not a
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  direct effect and perhaps delayed senescence so
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  if your plants are growing for too short a period this can keep them greener
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  for longer and so there's been a number of research trials looked at look at
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  this tomatoes treated with 50 micromolar melatonin and hydroponic solution showed
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  increased root to shoot biomass.
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  So more roots than shoots, the ratio increased.
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  A lettuce treated with 100 micromolar, melatonin had higher antioxidant levels
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  and delayed leaf senescence under high light stress.
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  So if you've got the really powerful lights and you want to really push them
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  even further than perhaps a low dose of melatonin in your.
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  Fertigation solution might be an option or a foliar spray but
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  you do highlights you probably don't want to put a foliar spray because you
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  could you know anytime you spray your plants there's in danger of
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  scorch so bottom line endogenous melatonin
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  is a natural regular plant growth stress tolerance and circadian
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  rhythms and applications of melatonin
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  what we call exogenous melatonin can enhance
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  stress resilience growth photosynthesis and
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  secondary metabolite production unlike a lot of
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  biostimulants and stress compounds it is water
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  soluble as well so you don't need to worry about getting it
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  into solution so yeah maybe you
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  want to look at if you're interested in melatonin it's probably completely safe
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  let's have a look see what the hazard rating is for melatonin i can't see any
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  obvious hazards safety warnings or anything like that and in fact you You can
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  buy melatonin as a herbal remedy,
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  well not a herbal remedy, as a natural supplement you can buy it.
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  It's actually found, it was discovered in plants in coffee originally,
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  and they thought it was a by-product of the extraction of the coffee,
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  but then they realised the melatonin in the coffee was actually coming from the plants itself.
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  So when you have a cup of coffee, you're having a small amount of melatonin.
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  The stress-reducing hormone that when you go into the daylight and the summertime,
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  makes you happy okay that's been
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  hydroponics daily for today if you found this interesting and useful please
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  you never miss an episode and check out utreema.co.uk because we have many biostimulants
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  fertilizers and organic biopesticides that you won't find anywhere else until
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  tomorrow thank you very much for listening goodbye.