Breeding for resilience - Controlled Torture Chamber

Greetings, one of my personal calls to chuck pollen is to search for resilience.

Powdery mildew and native bugs in the early spring are two directions that i would love to focus on!

Problem being i can find out within the first two weeks of coming outside in the spring with seedlings will shake off the bugs and new weather conditions, eventually they all experience various degrees of powdery mildew when the time is right, confirming to me i have nit yet found my outdoor keeper.

Question
How can i, in an residential home, with a dedicated grow room (our domestic goal has always been, clean room, clean surrounding rooms, clear clean boundaries between home and hobby life.) create powdery mildew conditions indoors that doe not spread and damage our home or 10x10 garden that we ideally want to have dialed for great VPD and constant good growth.

I consider a terrarium to stress cuttings but am scared about creating pm on purpose and things going horribly wrong in many unforeseeable ways i haven't brainstormed enough about
:friends:

sounds good, I would do outdoor selections.

Maybe try Durban X White Widow

I think ideally you'd want to have a kind of mildew parent stock, so you can elliminate variation with random mildew outdoors in different years.
I think mildew resistances pretty often involve race specific resistances, although I don't know if that applies to the species that infects cannabis too, but it would seem logical. so a plant may be completely immune to 1 race of the fungus, but not to another.

which means that if you just use whatever is floating around randomly, you may test different races of the fungus in different years, which might give you a false picture.
you can also breed for non-race-specific resistance, but in such a system where race specific resistance exists, that means you will have to select away from the completely resistant ones, since those are likely to have a race specific resistance, and you cannot see what level of race non-specific resistance is hiding underneath.

so ideally you'd want to take a sample of mildew once, and then see if you can somehow grow that mildew so you can constantly use a known isolate to test. and then to really do it well you'd need multiple isolates so all the races that are around in your region are represented in the end(for race non-specific resistance just 1 isolate from 1 race could be enough though).

I'd also look into if there are easier/convenient ways to test for mildew, like detached leaf assays. I don't know that much about mildew(also never had to look into it, since in over 10 years of growing outdoor I've never seen any mildew in my cannabis), but for other fungi I know you can do detached leaf assays. but it might be that since mildew is biotrophic it's not as easy(I don't know if you can culture it oin a petri dish or if you need to grow it on a live plant, if you can grow it on a petri dish it's much more convenient and easy, but since it's biotrophic it might be that that does not work).
the advantage there is that you can take just a few leaves, the rest of the plant continuees to grow and you can evaluate it on all other traits and keep the fungus out of your growroom. and single leaves are pretty convenient to put away in a box somewhere, does not take up much space and the fungus is confined to the box you put it in.

however in such a case you would have to maybe do a little testing to confirm wether the results from a detached leaf assay match what you'd find outdoor, so test some where you know about how resistant they are, and include an extra vulnerable one too if you can, and see if their ranking from such an assay matches what you'd expect.

for the bugs it may be easiest to just do the selection outdoor, since it sounds like you're looking for tolerance to multiple unspecified bugs. if you know a specific bug you want to breed tolerance for you could do stuff like introducing that bug in your growroom, later build cages around plants(if in a room full of plants 1 has less damage that might just be the bug does not really prefer it, but will eat it. if you lock the bug in a cage with just 1 plant, the bug has to eat it or starve, so if in that case too the plant suffers less damage you're onto something)

Grnhlthnhapyns said:

Question
How can i... create powdery mildew conditions indoors that doe not spread and damage our home or 10x10 garden that we ideally want to have dialed for great VPD and constant good growth.

Click to expand...

Trying to understand your setup here - is it that you start seedlings inside, then move them outside, and then move them back inside to flower? Or do you have two separate grows (inside and outside)? Whats the connection between the inside and outside grows? Is powdery mildew a problem on the outside plants, or only on the inside ones?

My first thought is that, if PM is a problem for you every time you grow, then you already have your torture chamber - its your current setup. If PM is consistently present, and you are selecting the best plants under those conditions, then you are already selecting for resistance by default (if the plants you prefer as seed or clone parents each time are those least effected). You could have a terrarium with deliberate PM infestation - but it would be difficult to keep the spores contained, and I'm not sure what it would gain?

In terms of raw material for breeding that has good mould resistance generally, why not try some of the Himalayan landraces from The Real Seed Company (Johaar, Kumoani, Nepalese, etc)? Currently they are giving away 12 Kumoani as freebies with each purchase. Cant recommend the RSC highly enough.

Wow what alice said Is reading my mind

powdery mildew is a fungus that is spread by spores, and its 'special move' is that those spores can settle on a plant and start growing in conditions that are drier (less humid) than those usually required by fungus to start growing.


As a cannabis grower and a general gardener (weed is a pretty easy plant to grow in the great scheme of things) i find that water stress is the greatest cause of PM, or at least the greatest cause that you can do something about.... Plants that get too dry between waterings become susceptible... and also plants that have become rootbound in their pots before being planted out or up-potted often will get PM later in life - so those factors are worth considering.

Keeping the air circulating is a good way of stopping PM spores settling on them, as is good ventilation, and keeping down humidity (PM still needs SOME humidity to thrive)


that doesn't answer your breeding question ,but may give you some ideas of avoiding or creating the conditions in which PM thrive.



VG

I don't think it would be wise to introduce any type mold indoors under any condition.

Just grow plants outdoors and expose them to powdery mildew instead if that's your plan.

Agree Troutman. I know my idea is unorthodox. Our outdoor conditions are powdery mildew friendly.

I was thinking of how on a micro level of hobby/passion breeding/growing could i select and grow inside throughout the year and make crosses that would thrive when planted outdoors.