I am going to leave this here for folks concerned about old seeds. If you are going to try and germinate old seeds PLEASE sterilize the surface first! Remember that a seed is a tiny little sterile packet. Everything INSDIE the hull is a sterile environment so you need to clean the outside of the house!
To surface sterilize seeds:
Preferably in a sterile environment:
90 seconds of agitation in 70% Isopropyl alcohol, DI water rinse.
3 minutes of agitation in 3% H2O2 DI water rinse.
13-15 minutes of agitation in 10% household bleach followed by 3 DI rinses
Maintain sterility!
24-hour soak in DI water to soften shells.
If you want to try an “assist” then during your final soak add some GA3. I would recommend 50ppm-200ppm.
If you get tails then rinse and plant them or rinse and leave them in a wet towel. Try to get your GA3 rinsed off as the seedlings will stretch like a mofo.
If you do not get tails the seed hulls are now soft enough to crack open, peel apart, and rescue the embryo. Since they are sterile they can go right onto seed starting culture media.
I tried to put some cuts on rock wool medium as normal old school cuts on the fridge and test how much they survived.
Naturally I failed and after 8 weeks the cut where completely dead.
I would like to try again using tissue culture protocols and medium, but still leave the samples on the fridge ( light on only when opening the door).
The whish beyond is to keep a cut in “stasis” for a long time…
When required, remove them from the fridge and grow under light as normal tissue culture.
I think there might be some info missing. Were these rooted cuttings or unrooted?
Ex vitro plants use photosynthesis to survive by pulling carbon out of the air in the form of carbon dioxide.
In vitro plants are offered a carbon source in the form of sucrose in the media so they do not need to photosynthesize.
For plants to photosynthesize light is required.
Removing light is possible and will slow down the growth process as will dropping the temperature. Controlled environments are ideal for being able to mimic the effects of nature. (Specifically, like Spring and Fall) and are commonly used to control and remove systemic pathogens in combination with anti-pathogenic media.
If you insist on doing this ex vitro, then my recommendation might be to try to create a mini-fridge style, low-growth chamber where you can still provide light but the plant grows very, very slowly due to cooler temps.
If using tissue culture, organogenesis is possible with MANY types of plants. This means that you can convert a plant organ like a petiole into a callus, a chunk of undifferentiated cells, using auxins or callus-inducing cytokinins. You can divide and store callus for long periods, and then under the influence of cytokinins, re-differentiate callus back into shoots. While cannabis-specific protocols may be well-defined they are not published.
Cannabis cultures well as very specific temperatures as noted in Conor’s thesis. You can see that lowering the temperature is potentially deleterious but can be done with specifically optimized media that would take some R&D.
