Question
Hi,

have you ever heard or experienced the Aspirin's application on plants to boost up the health and/or immune system ?

Pls read http://www.plantea.com/plant-aspirin.htm

It sounds strange for me in the first place but if it's true, why not ?

Rgds,

Ari

Answer
Aspirin -- Acetylsalicylic Acid -- belongs to a family of drugs containing Salicylate, a common plant hormone.  (The 'Acetyl' prefix in 'Acetylsalicylic' is routinely found in many organic compounds.) Salicylic Acid is one type of Phytoalexin -- one of many defenses that plants use to make their lives safer, longer, and more productive.

The idea that plants would have immune systems did sound ridiculous -- until scientists found out about Phytoalexins.  To me, the whole concept of a 'plant immune system' sounds like something I'd expect to hear about from people who do things like talk to their plants, between the Tarot cards and the tea leaves.

And yet...there's this Phytoalexins thing.  Botanical WMDs.  Hormones like Jasmonic Acid, Ethylene, Abscisic Acid and Salicylic Acid tell plants it's time to launch the Phytoalexins.

In simpler times, plants were perceived as passive, defenseless organisms that grew starward and came in green.  Some were on the beastly side (bug-eating Pitcher Plants and Venus Fly-traps).  Only 3 that I knew of should be avoided (Poisons Ivy, Oak and Sumac).  A few Cactus plants had the luck to be surrounded by dagger-like armor.  And if you ate, say, the wrong Mushroom, you would die.  Friends of mine who ate the right Mushroom, well, they very much enjoyed that kind of poison.  But plants as a family were simple brainless creatures.

How wrong we were.

Brainless plants produce strong, sometimes deadly chemicals that ooze or pour out of roots and stems and leaves (Urushiol, alpha-Terthienyl, etc) to discourage predators and parasites.  Some Root Exudates search for partners and prey underground in the Soil around them.  They can be friendly.  They can be hostile.

Researchers have watched plants engage in self-defense during an insect attack by releasing Jasmonic Acid -- an anti-insect hormone.  Juglones produced by the Black Walnut, or Terpenes made by Pines and Cedars, toxify the surrounding Soil, turning it into a no-fly zone for other potential competitors.

You run into Terpenes compounds a lot around the Holiday Season; this is the smell of your Christmas Tree.  To us, it's pleasant.  To other plants, it's poison.  Colorado State's Entomology Dept issued a cheat sheet on certain Terpenes a while back that reported: 'Monoterpenes have been found to have antimicrobial activities...'   High concentrations of Terpenes in a plant are easy to recognize because Terpenoids are volatile as well as highly aromatic.  This is how they get rid of potential predators.  It's also how they are also able to lure certain insects closer, say, to pollinate flowers.  Terpenes are one type of Phytoalexin.

Thiomethoxam, discovered by the agribusiness research and manufacturing company Syngenta and marketed as 'CRUISER', was developed as a Seed treatment, shielding Seeds with built-in insecticide.  Syngenta learned later that Thiomethoxam had a side benefit: It turns on Proteins that respond to stress factors  -- Proteins needed for repair.

CRUISER-spiked Seeds grow faster, stronger, even boast a higher crop yield.  Scientists now think they know why:  A stressed out plant that does not have to spend energy on its own immunity can pour all its resources into growth and vegetable production.

Syngenta makes something else called 'Actigard', the trade name for benzothiadiazole (BTH).  When microbes -- Bacteria or Fungi -- attack a plant, BTH stimulates the Salicylate Pathway.

Harpin Protein, sold as 'Messenger' and made by Eden Bioscience, turns on the Salicylate Pathway AND the Jasmonate Pathway.  Another side effect:  It boosts nutrient uptake and revs up photosynthesis.

Immune responses?  Does this walk like a Duck?  Does it look like a Duck?  Does it quack like a Duck?

But you asked about Aspirin.  Acetylsalicylic Acid.

Given that the Salicylic Pathway is a function few plants can do without...

Given that Salicylic Acid is central to the biochemical 'Salicylate Pathway' defense...

Given that some of our greatest thinktanks spend millions to find chemicals that are part of the natural defense system of the Plant Kingdom...

It is starting to look like feeding Aspirin tablets to your plants may not be such a flaky idea, after all.

Thanks for writing.

THE LONG ISLAND GARDENER