Mechanical Wounding to icrease trich production?

[Iffy]

Hi Folks,
Read this interesting article, following a thread about increasing trich production using Chitosan. (Something I'm pursuing).
It seems scientists use forceps to affect mechanical wounding to the leaves of the plant, inducing a Jasmonate-mediated defence response - FROST!

http://link.springer.com/protocol/10.1007/978-1-62703-414-2_5

Anybody tried this procedure before?
I would love to hear your responses.
Stay safe & happy growing

PS
Further reading has shown that wounding can take different forms e.g. Cutting or punching a hole in the leaves. Crimping the leaves or cutting in from the edges. However, mech damage only releases a limited set of VOC's (volatile organic compounds), compared to a more complete set from Herbivorous damage. To get a 'complete' set of VOC's apparently requires both! What little munching creatures did they use I wonder???? More reading.......
http://www.plantcell.org/content/12/5/707.full

 

[Iffy]

Wow, I can't believe nobody's at least tried this.....

Ok, let me put some flesh on the bones. This is what I intend to do:
I'm going to run a side-by-side experiment on my next run, which will be Nirvana's ICE. My usual 12 plants in my NFT table & from week 3 of flower through to week 5 I'm going to foliar spray the first 8 with a mixture of Chitosan, GA3 (Giberelllic) and a touch of Wet Betty. The end 4 plants will be shielded during spraying and will receive nothing.
The first 4 plants, when getting sprayed will also be subjected to bouts of 'mechanical damage' in the form of a small hole punch. I'll nibble at the edges of the leaves with it & punch a few holes in the leaves. From what I've read, this 'mech damage' needs to be an on-going, continual thing if you're going to fool the plant into sensing 'insect attack'.
So to re-cap. The first four plants will get sprayed & munched. The next four will be sprayed only and the last four will get nothing.
I'm hoping that if either or both of these treatments have a positive effect on trichome production, it will be quite evident by the increase in frost.
So my mothers are ready to be cloned. Just waiting for my present grow to finish (4-6 days) A big clean down & I'm ready to go.
I will be updating my grow diary of Nirvana's ICE with progress, especially in regard to this test.
Your comments, advice would be most appreciated.

 

[OG_TGR]

Curious. I have never heard of such a method. I look forward to seeing your results.

 

[Iffy]

Curious. I have never heard of such a method. I look forward to seeing your results.

Hey OG, I know. It didn't take much research on my part, into what caused added trich production. Loads of scientific tests have been carried out on 'control' crop plants with positive results. I can't believe that no-one in 'our' industry is using this technique. Chitosan clearly is in use, AN's Bud Factor X has it in but I've never heard anyone trying mechanical damage, especially as all the scientific reports I've read state that the best results were achieved when BOTH techniques were used together. I struggled to find precisely what form the M/D took until I found one report that outlined the basic tactics. One is to crimp the leaves with forceps, another is to use a small hole punch. I chose the latter, because I've got one! Lol.
The procedure was quite confusing as to how much & how often but what was clear in the reports was that it had to be a continuous, daily treatment. So I'm just going to nibble at the edges and punch a few holes but do I attack every leaf on the test plant? Do I just attack the fan leaves?
I'm just going to have to 'suck it & see'. I'll keep you posted

 

[Only Ornamental]

Hi

Well, it is known for some time that just cutting or squeezing doesn't mimic herbivorous damage and neither stimulates the whole defense system... Good to know that it still can be simulated now!

Concerning the leafs to treat/pinch/perforate: A friend of mine published something about that lately:
Chauvin A, Caldelari D, Wolfender JL, Farmer EE.
Four 13-lipoxygenases contribute to rapid jasmonate synthesis in wounded Arabidopsis thaliana leaves: a role for lipoxygenase 6 in responses to long-distance wound signals.
New Phytol. 2013, 197(2), pp. 566-75


The trick is thus to pinch a leaf on each side and the next one being 3-4 internodes higher (in case of thale cress); same for the leafs being 90° turned with regard to the first treated ones because the leaf produces jasmonate and derivatives which are transported longitudinally along the xylem only over a few internodes. As you want to get the trichomes on the flowers to grow, you can neglect (if extrapolation from one species to another is valide) the lower fan leafs and only torture those close or in the buds (the more leafs the better).

Question: Does the jasmonate pathway really induce trichome production (number, size)? I know, because friends of mine work in this field, that certain stimuli like intense UV irradiation cause an increased defense signalling and hence the production of more and/or new secondary metabolites but cause no or not necessarily morphological changes. That means, you get a different cannabinoid and/or terpene profile and with luck more THC (if it's what you're seeking) per trichome but not more trichomes. Certainly, that claim on my part remains to be proven... By chance, we did test hemp and stress and there was a change in the metabolic profile (unpublished data) but nothing interesting for us and we did not look at cannabinoids.

Hope that this helps you somewhat .

 

[Iffy]

Hi

Well, it is known for some time that just cutting or squeezing doesn't mimic herbivorous damage and neither stimulates the whole defense system... Good to know that it still can be simulated now!

Concerning the leafs to treat/pinch/perforate: A friend of mine published something about that lately:
Chauvin A, Caldelari D, Wolfender JL, Farmer EE.
Four 13-lipoxygenases contribute to rapid jasmonate synthesis in wounded Arabidopsis thaliana leaves: a role for lipoxygenase 6 in responses to long-distance wound signals.
New Phytol. 2013, 197(2), pp. 566-75


The trick is thus to pinch a leaf on each side and the next one being 3-4 internodes higher (in case of thale cress); same for the leafs being 90° turned with regard to the first treated ones because the leaf produces jasmonate and derivatives which are transported longitudinally along the xylem only over a few internodes. As you want to get the trichomes on the flowers to grow, you can neglect (if extrapolation from one species to another is valide) the lower fan leafs and only torture those close or in the buds (the more leafs the better).

Question: Does the jasmonate pathway really induce trichome production (number, size)? I know, because friends of mine work in this field, that certain stimuli like intense UV irradiation cause an increased defense signalling and hence the production of more and/or new secondary metabolites but cause no or not necessarily morphological changes. That means, you get a different cannabinoid and/or terpene profile and with luck more THC (if it's what you're seeking) per trichome but not more trichomes. Certainly, that claim on my part remains to be proven... By chance, we did test hemp and stress and there was a change in the metabolic profile (unpublished data) but nothing interesting for us and we did not look at cannabinoids.

Hope that this helps you somewhat .

Oh man, the best thing I've done in years was to join this site!!
Double-O that was pure gold! It's given me a clearer idea of how to proceed and perhaps given my expectations an edge of realism!
I appreciate the distinction with perhaps the altered cascade of VOC's, as opposed to an overall increase in mass (trichomes).
The thinking of leaving the fan leaves alone and focusing on the 'sugar' or close leaves is I think sound.
I think if the mech damage is done keeping the idea of 'insect attack' in mind and nibbling away as such, will be best and as you point out - ensuring balance to all main branches. I also think if it's going to have any effect at all, it's going to have to be maybe twice daily or maybe even more frequently.
We shall see, it should be interesting anyway.
Thanks again Double-O for your intelligent and practical input.
Stay safe & happy growing

 

[Iffy]

Hi Folks.
Had to share this link to some real information on this topic

http://www.plantphysiol.org/content/137/3/1160.full.pdf

 

[ozza]

intersting so bugs attacking could help your plant?

 

[Only Ornamental]

Naw ozza, bugs would just eat your plant !
The trick would be to imitate the bugs by continuous mechanical wounding of specific leaves (obviously those you don't want to smoke). Question is whether this sort of stress elicites not only some stress response but a specific response resulting in higher resin production and/or higher THC content of the resin (preferably without reducing overall harvest quality and quantity).

In outdoor growing (no matter of what) one usually has bugs and there it is a delicate balance between bugs attacking the plants, the plants fighting back with its chemistry and you fighting the bugs back with yours too (if you're not an organic grower). If you're lucky...
I guess no one would risk it by cultivating herbivoures in his vegetable garden, even if a certain level of natural stress augments resin/THC, smoke quality or whatever... Too often, those critters eat exactly the parts you yourself want to consume (or the simply eat the whole damn thing).

 

[Only Ornamental]

Ouups... forgot something...

What do you define as "help the plant"?
Stress never "helps the plant" but it redirects energy otherwise used for growth towards inducible defense mechanisms (i.e. secondary metabolite production like cannabinoids and terpenoids) and that may "help" you .