PM linked to Genetics?

sprinklememaynee · December 23, 2021, 12:27pm

I was hoping to get some input from the community around this odd issue I have been having. I purchased 9 of the CBD Pink Kush Auto Fem’s from Seedsman in the spring, and every single one I have popped has been decimated by PM at different points. These plants have been grown both indoor and outdoor, and with different nutrients, and medium. I was wondering if there is a genetic predisposition from some cultivars to develop PM. The PM shows up generally right when flowering starts, and I have been able to hold it off, but it always comes back and results in zero yield and a trip to the green bin for the plant.

Also, the other plants with different genetics that have grown alongside it have experienced zero PM, and I am at a loss lol.

Wondering if anyone has any insight into PM being hard coded into some genetics.

corey · December 23, 2021, 1:47pm

That’s above me. Its a Good question.

Sunvalley · December 23, 2021, 1:37pm

Some plants are just way more susceptible to PM than others. If the parent strains had a pm issue when developing the seeds, the seeds would in turn have a built in genetic resistance to PM more so than before.

vernal · December 23, 2021, 1:41pm

It’s an infection, spores are in the air. Running conditions conducive to mildew and you’ll get it every time. Leaves touching, poor spacing, poor airflow, bringing infected plants in your garden and increasing spore load, etc.

Some stuff is more resistant, some stuff less. It is not “hardwired” into genetics that say you’ll get mildew.

It isn’t a genetic disease, it is just an opportunistic fungus. Same as yeast in the air turning your apple juice into wine. Same as green mold taking taking over that bread you forgot about. Give it an opportunity and enough time and it will take hold. Nature abhors a vacuum.

sprinklememaynee · December 23, 2021, 2:30pm

Perfect! Thank you so much for the helpful info! I will try another one, and be very mindful of the airflow as well as leaves touching. I may have to be more thorough in my defoliation. I keep the humidity in my tent at 50% and the temp at 19 degrees celsius, so it may just be a defoliation issue this run.

vernal · December 23, 2021, 3:43pm

Number one thing is constant 24/7 good airflow. Heavy foliage can really slow that down in canopy interiors, and is usually where spots of mildew will appear first.

MBVapester · December 23, 2021, 4:55pm

Wondering if it could be possible that it could have travelled in the seeds if the grower had it as well and if it’s more susceptible then it would show up again.

sprinklememaynee · December 23, 2021, 5:04pm

It may be a batch issue, i am 3 for 3 with severe PM on those seeds.

Sunvalley · December 23, 2021, 5:07pm

What are the parent genetics?

sprinklememaynee · December 23, 2021, 5:09pm

its purportedly Kush Rose Auto CBD x Afghan Rose Auto CBD

Sunvalley · December 23, 2021, 5:09pm

How far into flower are you? Are you in pots?

sprinklememaynee · December 23, 2021, 5:12pm

The one I just chopped last night was just starting to show some pistils.

The other ones showed a little bit of PM in early flowering,

Sunvalley · December 23, 2021, 5:20pm

It’s difficult for me to grasp your environment as I’m in South Africa, but if that plant in 1st Pic had just showed, then I’d do a sulfur dunk and let it be. Basically get a Lime Sulfur (it’s organic) liquid, diltue to the required amount in a 5 gallon bucket and dip it in like you would a dog, wash it all around, up pot if you can or just hope for the best in those current pots. If it starts showing up later into flower you can use other stuff to keep it at bay in a way that won’t ruin your terps

sprinklememaynee · December 23, 2021, 5:23pm

Thanks for that! I am going to run a tent full of it next go, to try and tease out why it keeps happening. I feel as if i run 6 more and all 6 get PM, there may be something else at play.

Sunvalley · December 23, 2021, 5:28pm

If it does show up just remember that more and more spores will be hiding off that regardless of how well you clean. So I’d say if you have a better strain or access to more resilient stuff I’d say avoid growing the pm prone stuff and go fwd on that. PM is a bitch to get rid of once it settles in

sprinklememaynee · December 23, 2021, 5:41pm

For sure! Those seeds may be better suited to being stored. I have no shortage of stuff that has not shown any PM.

GMan · December 23, 2021, 6:30pm

Take this for what it’s worth, but a couple of things that might help are treating your plants early as a preventative before you even see it, especially this particular strain. Just spray them good top and bottom of the plant (it’s easy to turn them upside down and completely dunk/immerse the entire plant by wrapping a towel or something around the pot to avoid losing soil).

I started adding powdered silica (AgSil-16h) to my water and it seems to work as a preventative by making the plant cell walls stronger thus making the plants better equipped to deal with it on their own.

I believe some plants are more susceptible to PM than others but not the mechanics of it. I lost my entire last grow to PM, too. I was between paychecks and didn’t have much to work with so I did my best at cutting what I could see, out.

By the time I chopped them they looked like different plants. It was like all of the life was sucked out of them from the inside out. I did bud wash at the end to remove what was on them with baking soda and lemon juice.

I hung my plants afterwards to dry and dried out in about 2-3 days and I mean dry to the bone. They didn’t weigh anything and they tasted pretty bad.

I tried curing of sorts by adding a little moisture back but they still suck.

I’ve had plants growing side by side with one infected and nothing on the other. So, some plants are definitely more prone to getting it than others.

So, prevention is the key. And, there was a YouTube someone posted about how a perfectly healthy plant can’t get sick or fall to molds, etc. I haven’t watched it yet but that’s always been my belief as well. I’m just still trying to figure out ho, exactl, to do that every grow, lol. I’ll try to watch the vid and post it if I like it. Good luck. I hate that stuff with a passion and never saw it before I moved here. peace

sprinklememaynee · December 23, 2021, 6:38pm

Thank you for that! Looks like I am going to try and get some powdered silica. I ran one of the plants the same way, and tried my damndest to get it to the finish line, but it had lost its zeal by that point. I was able to save some flower, but it was terrible after drying and curing.

The mystery of PM is so frustrating to me, especially when I have a super healthy plant, and then beside it another plant with so much PM. Either way, this thing is a journey, and I too am looking for a way to give the plant the respect it deserves by having a perfect environment and adequate nutrition.

Rogue · December 23, 2021, 7:31pm

These plants grow in the desert.
Keeping humidity down is the main thing.
Water as little as possible, and from the bottom.

Trowertripper · December 24, 2021, 12:27pm

I keepmy dehumidifier on blast 24 /7 regardless of rh. Keep temps on the cool side and fans every where making leaves dance a little.defoliate and spray with thymol/oregano oil if they get it in flower or bonide if its in vegggg.