[plastochron]

Hello all,

I've got a question for all you scientifically inclined breeders, growers, and stoners: if you had access to cutting edge analytical chemistry, genetic, and plant science instruments what aspects of cannabis science would you investigate?

This is not a hypothetical question. I am legitimately looking for some more ideas on relevant research to pursue. I have access to a long list of cutting edge instruments and have the capacity to design and run experiments fit for academic publication (not that is the end game by any means).

So let's hear some ideas, however far out or jargon filled.

Let trial be made!

[mad professor]

drop me an internship first man, lab rat will work for having their name on research!
j/k i've gotta a couple ideas, lemme think of better ways to express them though.

[plastochron]

by all means. hplc-ms access is a given for the analytical chemistry. i don't have access to a qPCR at this moment, but i'm certain i will in the near future. in terms of horticultural instruments, i have access to everything that one would need to quantify environmental conditions (PAR, temp, RH) and nutrient uptake.

[knna]

Some things I'd love to be tested with a good equipment on controlled conditions:

-Long term (after adaptation) effect of high CO2 levels on photosynthesis and photorespiration, chlorophill levels, stomatal conductance, yield, ratio flower to stem/leaves, main cannabinoids levels,terpenoids, etc. This mean not only grow cannabis under controlled high CO2 levels (from 1000 to 2500ppm, for example,on 500ppm steps), comparing initial levels with them once adapted, but too compare figures not only with a control growing under atmospheric CO2, but compare during blooming plants already adapted (vegged on enriched CO2) to others which not.

Ideally, performed on a range of temperatures. Say, 20, 25, 30ºC initially, and with narrower temps over 30ºC later. Adjusting VPD to get constant levels between treatments by varying relative humidity.

-Characterize photosynthetic response under high irradiance conditions found on cannabis growing, under atmosferic conditions and CO2 enrichment (moderate, say 700-800ppm, up to 1000).

First, not adapted plants response on 2nm isolated waveband intervals. Later, the same for plants adapted to differential light regimes. Either pure ones (just Blue, Green or Red) or dominant ones (very rich on B, G and R, but with say, 10% of each of the other bands) and compare response with no adapted (or sunlight adapted).

Finally, measure photosynthetic response of 2 or 3 wavebands intervals combinations: 435, 450, 470, 500, 530, 560, 580, 600, 615, 630, 645, 660, 700 and 725nm (2nm wide). Keeping constant photon count or absorbed photons (anyway, reflectivity and transmitance data is a must). Ideally, performed on both control (sunlight or full spectrum light) and adapted (B, G, R groups).

Concepts to be measured: photosynthesis, stomatal conductance, internal CO2 concentration, chlorophill fluorescence, PSI and PSII activity. Transverse chlorophill fluorescence for the most relevant results would be ideal, in order to see the photosynthesis response to the deepness gradient into the leaf.

If possible, any good experiment with cannabis should use identical clones (of course), but of 2-4 typical and differenciated genetics, due the strongly variable response of different cannabis genetics to the topics suggested.

The best experiment on light quality response should measure cannabinoid and main terpenoid levels for each group.

-Related to this, study the cannabinoid and terpenoid variation under different light regimes or with constant ones adding UVA, UVB and both. Far red could be tested aswell. Putting special enphasis on harvest time: harvest of each group by steps so the comparision can be done to similar rates of maturation and not to the same growing time; or harvesting by tricomes colors (somewhat subjetive). Anyway, taking in mind the differential time of maturation when growing under different light regimes (a problem I found on all scientific studies on cannabis response to lighting)

As we know that UV and far red effect is very dosage dependent, study should use some irradiance levels for each.

[dizzlekush]

Originally Posted by knna

Long term (after adaptation) effect of high CO2 levels on photosynthesis and photorespiration, chlorophill levels, stomatal conductance, yield, ratio flower to stem/leaves, main cannabinoids levels,terpenoids, etc. This mean not only grow cannabis under controlled high CO2 levels (from 1000 to 2500ppm, for example,on 500ppm steps), comparing initial levels with them once adapted, but too compare figures not only with a control growing under atmospheric CO2, but compare during blooming plants already adapted (vegged on enriched CO2) to others which not.

Ideally, performed on a range of temperatures. Say, 20, 25, 30ºC initially, and with narrower temps over 30ºC later. Adjusting VPD to get constant levels between treatments by varying relative humidity.

-Characterize photosynthetic response under high irradiance conditions found on cannabis growing, under atmosferic conditions and CO2 enrichment (moderate, say 700-800ppm, up to 1000).

Concepts to be measured: photosynthesis, stomatal conductance, internal CO2 concentration, chlorophill fluorescence, PSI and PSII activity. Transverse chlorophill fluorescence for the most relevant results would be ideal, in order to see the photosynthesis response to the deepness gradient into the leaf.

If possible, any good experiment with cannabis should use identical clones (of course), but of 2-4 typical and differenciated genetics, due the strongly variable response of different cannabis genetics to the topics suggested.

^This^ Although i would test CO2 at a range from 750-1750ppm with 250ppm increments as Cannabis sativa L. has already been thoroughly tested to 750ppm and it is well established that 1800ppm is supraoptimal concentrations of CO2 for C3 plants.

Also quantifying temperature/humidity/VPD/CO2/PPFD/air flow effects on volatile terpene tissue concentration is something worth experimenting with IMO. Certain conditions may increase growth rates but might cause a lower terpene concentration in tissue due to effects on evaporation/production rates.

[Nunsacred]

We want doubled haploids.
Please concentrate on finding a simple reproducible and efficient way of generating these in cannabis.....

[plastochron]

thats quite the list of photosynthetic analysis. although i have LICOR experience, that will be the most difficult instrument for me to gain continuous access. while i agree that studies examining the impact of [CO2], light intensity, variation in spectrum and presence of particular wavelengths, variation in VPD and temperature, etc. on photosynthesis and certain quantifiable photosynthetic properties, keep in mind that i am operating in reality and undertaking trials with dozens of treatments that all require meticulous environmental control is a big undertaking. assuming that i can access a LICOR (hopefully one of the newer models with all of the bells and whistles) i would be most interested in investigating the influence UV and far red spectrums on CB/terp concentrations. as far as CO2 enrichment trials go, i am most interested in investigating interaction of CO2 enrichment and deficit irrigation. knna, i am also quite interested in looking at the impact of veg time acclimation to CO2 enrichment compared to non-enriched and only bloom enrichment (the only catch is, i am confident that the results will be pretty predictable, with the veg-flower CO2 enrichment resulting in the greatest yield). dazzle, you may be correct about the yield increase from CO2 enrichment coming at a cost to CB/terp concentration, but i would be surprised if it was significant; CBs/terps are products of secondary metabolism; these products are essentially byproducts of respiration and photosynthesis, so increases in these processes may simply yield a greater yield and a similar concentration of compounds of interest.

i would really like to examine the influence of manipulation of hormone levels (either thru exogenous application or through inducing an endogenous response) on PSN and secondary metabolite production. deficit irrigation in combo with CO2 enrichment would be an example of one such trial.

please keep making suggestions. we can all contribute to making an experimental design, execute the experiment, and submit it for ICmag publication. what do you all think?

[dizzlekush]

Quantify the effects of different concentrations of exogenously applied (via foliage) Methyl Jasmonate, Methyl DihydroJasmonate, 12-Oxo-phytodienoic acid, and Jasmonic Acid Carboxyl Methltransferase (if possible) on cannabinoid/terpene/trichome production and mitosis.

Quantify the effects of different concentrations of exogenously applied (via foliage & also seed soak for brassinosteroids) Triacontanol, brassinolide and 24-epibrassinolide on cannabinoid/terpene production, root mass and yield.

Quantify the effects of different concentrations of foliar applications of 6-Benzylaminopurine both stand-alone and co-applied with the above mentioned jasmonates on cannabinoid/terpene/trichome production, mitosis and yield.

Quantify the effects of foliar applications of methanol at concentrations varying from 1-30% aqueous methanol (and possibly ethanol) in many different light environments (ranging from 150-2000PPFD) and different VPD (not different VPD for actual application time though) on yield and trichome density/physiology.

In that order, im a sucker for PGRs....

[plastochron]

as am i... though i would always prefer to try to induce endogenous production or apply naturally derived sources of them. what is your logic for only testing foliar instead of soil drenches? i have not heard of foliar applications of alcohols. what is the origin of this idea?... scratch that, a quick lit review revealed a heap of publications about foliar MetOH and EtOH trials (especially on tomato).

for some of these (e.g. triacontanol) there has been fairly extensive research published on a variety of plants; although there is always a need to verify the effects on cannabis, i believe that in certain cases one can extrapolate the findings that relate to general plant metabolism.

i am starting a brassinosteroid and sterol trial shortly.

[dizzlekush]

Originally Posted by plastochron

as am i... though i would always prefer to try to induce endogenous production or apply naturally derived sources of them. what is your logic for only testing foliar instead of soil drenches? i have not heard of foliar applications of alcohols. what is the origin of this idea?... scratch that, a quick lit review revealed a heap of publications about foliar MetOH and EtOH trials (especially on tomato).

for some of these (e.g. triacontanol) there has been fairly extensive research published on a variety of plants; although there is always a need to verify the effects on cannabis, i believe that in certain cases one can extrapolate the findings that relate to general plant metabolism.

i am starting a brassinosteroid and sterol trial shortly.

It is well documented in Triacontanol, Jasmonates and Brassinosteroids that foliar applications are better at inducing desired effects than soil drenching. an exception is applying higher concentrations of brassinosteroids as a seed soak as i previously mentioned testing. Im not so sure about applications of cytokinins actually, but im fairly certain its the same as well.

We cannot extrapolate (with any sort of accuracy) the effects of any of the above mentioned PGRs on terpene or cannabinoid production in Canabis sativa L, I guess you could get fairly close with mitosis & trichome density r.e. jasmonates and cytokinins (mainly BAP)... but optimal application rates of these PGR's change from species to species and often even by cultivar.

For instance experimenting on opium led to conclusions that optimal TRIA applications (via foliage) was 0.01ppm, while experimenting on tomato, sweet wormwood and the tiger claw tree (again via foliage) led to conclusions that 1.0ppm was optimal, 100X more concentrated than opium tested concluded. The opium experiment tested at 1.0ppm as well and had much less significant results while at lower ppms (and >1ppm) the other studies had less significant results.

I have personally tested TRIA and have found .75ppm-1.0ppm to be more optimal than lower ppm, although i havn't tested higher ppms.

As far as inducing endogenous amounts of the phytohormone how do you plan on doing that without applications?the only phytohormone i could thing of wanting to increase amounts of would be Jasmonates and Cytokinins. you could increase jasmonate via manually damaging leaves to mimic insect damage or increase UV-b irradiance. idk about cytokinins besides applying seaweed extracts, methanol, and of course cytokinins . BTW you do NOT want to increase endogenous amounts of brassinosteroids, that will stunt your growth.

May i ask the specifics behind your brassinosteroid testing? here are mine: I sourced my EBR from Epin (0.025% EBR)
https://www.icmag.com/ic/showpost.ph...3&postcount=37

I would love to see what lit you've found r.e. EhOH applications, i have only a study on tomates (whihh also studied MeOH) and one on papaya seedlings.