Is Powdery Mildew Systemic?

I have heard many things. I really am just wondering if PM is systemic and if so, does that mean it can't be completely eradicated... I know people have many ways to "kill it forever" but would the "cleaned" plant be more prone to infection than other plants that never had it ..maybe even just for the fact that the clean plant was never around a dirty plant. Does anyone know?
Phyte

Sorry, I don't know for sure, but gonna hazard a guess; Yes it is systemic or at least, might as well be. Thats the bad part. Good part is, PM is only really a problem where the conditions are right for it. Remove the conditions and you remove the PM. Usually, that means lowering humidity and increasing air circulation. Also, there is increasing evidence (in the 'straight' horticulture world) to support the use of potassium silicate products as systemic fugicides, instead of as a source of P as they're usually sold in the cannabis community.

Here's some links; http://www.pqcorp.com/products/SilMATRIX.asp
http://www.sarep.ucdavis.edu/Organic/tap/Potassiumsilicate.pdf

You can buy potassium silicate products in the hydro store now. They're not recognized by the cannabis community as fungicides yet. Only as a source of P and silica, which is controversial anyway. Yet another example of the (insulated) cannabis community lagging behind the ag researchers.

Mr. Greengenes said:

Sorry, I don't know for sure, but gonna hazard a guess; Yes it is systemic or at least, might as well be. Thats the bad part. Good part is, PM is only really a problem where the conditions are right for it. Remove the conditions and you remove the PM. Usually, that means lowering humidity and increasing air circulation. Also, there is increasing evidence (in the 'straight' horticulture world) to support the use of potassium silicate products as systemic fugicides, instead of as a source of P as they're usually sold in the cannabis community.

Here's some links; http://www.pqcorp.com/products/SilMATRIX.asp
http://www.sarep.ucdavis.edu/Organic/tap/Potassiumsilicate.pdf

You can buy potassium silicate products in the hydro store now. They're not recognized by the cannabis community as fungicides yet. Only as a source of P and silica, which is controversial anyway. Yet another example of the (insulated) cannabis community lagging behind the ag researchers.

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rep to greengenes! never hear that you could use potassium silicate this way!

Look up endophytic and epiphytic

http://www.apsnet.org/edcenter/intropp/LabExercises/Pages/PowderyMildew.aspx

it doesn't have to be. poor room conditions can bring it around. low light, other deficiencies, etc;

Good environmental conditions is key. As is cleaning your room good. I slacked a bit my last 2 harvests and have seen a few random PM drops on some of my leaves. Keep your humidity low, air circulation high, and clean your room good(with a disinfectant) and regularly and the chances go down quite a bit.

I live in the desert the only time I've had problems with PM is outdoors on my roses and it was from over watering.
Good Luck

I have never had PM. I have a nice seeds stash to work with but I also just arrived in the land of a million clones...I am just wondering if I get a "cleaned" bubba kush clone, then do I risk bringing an element in my garden that will have a greater potential to produce and spread pm?
Compost- what strains are you working with and which ones had the pm show up? I used to not be impressed with "kushes"...now all I want is some bubba and some chem 91...

420247- That was a relatively helpfully link...nevertheless, I am a little slow tonight...so, there are multiple types of pm? some that live in and some that live outside the plant...do you know which genera are more prone to host on cannabis plants? And is endophytic pm harder to eradicate if not impossible?

Long story short...I would like to get some clones, but I don't want to cause myself avoidable problems...I know I could have a quarantine box, but space does not permit..thanks for the imput

For all intents and purposes, yes. Thats why nothing short of Eagle20 cures it, and only treats exterior sympyoms. One appliction of Eagle20 kills the mildew from the inside out.

Judging by the way you treat for PM i would say no, but on the other hand an advanced infection may become internal. Good question! Now ill go read the thread!¬)

Theres alot of ways to kill PM & most are not systemic, never used E20 but hear good things. Ill stand by my initial remarks!

Potassium Silicate is great stuff! So is SA/ASA.(protectives+)- People with issues should induce SAR!

Mr Greengenes...sorry I spaced you...I have been meaning to pick up some silica blast. I hear it also does wonders with orchids which is another obsession of mine.

I don't necessary have the best grasp on what is organic and what is naturally derived but non-certifiable(ie humic acids). Is potassium silicate a synthetic salt compound? Can horticulture grade silica be naturally derived? Thanks for you feed back..your first post definitely helped my understanding...

Google/search! if conditions are less than optimal or harsh even, then PS would be a welcome additive with multiple benefits, not to mention the extra 'K'. ive been playing with increasing ratio's of PS for a couple of years now & will continue to do so! (no need to over do it though).

from what i have read in robert c. clarks book "hemp pests and diseases" PM is not systemic. it can get its organs "into" a plant but it does not spread that way. it can only spread on the surface. its reproductive organs "dig in" and are almost impossible to kill with sprays that are not systemic (eagle 20) or somewhat translaminar (dutch master saturator/penetrator mixed with zone).

I had some PM in flowering and it has only been on my white rhino. The white rhino is more indica then my other strains. The plants are shorter and very dense making it easier for PM to get going since its harder to get a good coat of neem oil on the inside leafs. The PM has not moved over to my church, himalayan gold, or my blueberry.

I am about to go with some eagle20 though so I can get rid of it for good.

Epiphyte said:

420247- That was a relatively helpfully link...nevertheless, I am a little slow tonight...so, there are multiple types of pm? some that live in and some that live outside the plant...do you know which genera are more prone to host on cannabis plants? And is endophytic pm harder to eradicate if not impossible?

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All PM I've seen growing on cannabis has been growing epiphytically

http://www.umass.edu/umext/floriculture/fact_sheets/pest_management/powdery_mild.htm

Fungicides with the active ingredients propiconazole (Banner Maxx), myclobutanil (Eagle, Systhane), triadimefon (Bayleton, Strike), fenarimol (Rubigan), thiophanate methyl (Cleary's 3336), potassium bicarbonate (Armicarb, MilStop), or sulfur are registered for Powdery mildew control on ornamentals.

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The Powdery mildew fungi can develop resistance to any of the fungicides, except sulfur, listed above so be sure to alternate fungicide applications among chemical classes.

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Lazyman said:

For all intents and purposes, yes. Thats why nothing short of Eagle20 cures it, and only treats exterior sympyoms. One appliction of Eagle20 kills the mildew from the inside out.

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Lazyman hit the nail on the head. See the below link for eagle20 info


https://www.icmag.com/ic/showthread.php?t=161425

Definitely systemic. I had never experienced PM in my life until I brought home a single med club cut and just put it in my veg cab without a second thought. Then BOOM, within a month every single plant in my library had PM. Just after I had finally wiped out a vexing repeat mite infestation by finally going with FloramiteSC. That's what I get for 'trusting my source'.

This was just before certain people on IC had discovered and were talking about Eagle 20, and I thought "no problem, I got this, just rotate skim milk, SM90 and Neem oil sprays". All three had been touted by individuals on IC as successful treatments for PM. Added some Ed Rosenthal Zero Tolerance fungicide to the arsenal and started spraying.

This approach seemed to work - no more spots on my mother plants, and the clones I took for my next run appeared healthy and PM-free, so I scrubbed down my flowering room and dropped them in my brand new experimental vert cages. My environment was completely dialed - HEPA-filtered intake air, multiple air circulators to stir the room, 10K BTU AC, 45 pint dehumidifier. Humidity never once topped 55%, was usually around 35-40%, high temps were in the mid-80°'s, nighttime lows between 65-70°. Dialed.

I continued to rotate my sprays, every 3 days throughout veg and for the first 2 weeks of flowering. The stretch was done, the vert cages were filled, and I had not seen even one tiny spot of PM, so I figured I was in the clear. Until week 4 of flower - a few small spots on some lower fan leaves of the strain that started the initial outbreak in the first place. I spent several hours meticulously inspecting the entire vertical canopy and spot-treating the few spots I could find. A few days later, more spots. Then more. I went ahead and sprayed the entire canopy with neem oil, little buds and all, something I swore I'd never do. It worked for about 3 days, then double BOOM, twice as many spots as before. I began removing branches, then a few whole plants. By week 8 it had spread all around the cages, and I was forced to harvest early to get anything at all. Some strains were completely unaffected, but unfortunately the ones with the most damage were the ones I had planted the most of. Got about 12 ounces of moderate quality PM-free flowers, and about 40 ounces of destroyed shit. It made a huge amount of gnarly amber QWISO, but it was one of the saddest things in my life to see that gigantic pile of ruined flowers in my garage. Months of hard work turned to shit.

Soon afterward I got hooked up with some Eagle20 concentrate by my boy Lokes. Cleaned every square inch of everything garden-related, right down to the digital thermometer, switch plates and plug adapters, with bleach. Pruned back all my mothers and gave them a dunk in E20. Once more a week later. PM has been completely absent ever since. I plan on adding Meltatox to my arsenal just to have it around, as well as a sulfur burner when I can afford one, and continuing to rotate treatments.

Even with my environment completely dialed, no external signs of PM for weeks and multiple preventative sprays in veg/early flower, that shit kicked my ass and destroyed my grow. I'd say that points toward a systemic infection.

Moral of the story - now I quarantine and pre-treat any new plant I bring in to my setup, first with FloramiteSC, then with Eagle20, regardless of the source.

I believe PM is systemic. I had never had PM and then my grandparents introduced some GDP cuts from their neighbors up the hill. Those plants got PM quite rapidly which leads me to believe that they were just washed off and gifted.

Since we trimmed our outdoor in the garage that housed the veg and flower room, i think the spoors spread to the veg room(flower room wasn't running). Well, no matter how much I tried to get rid of the PM it would just come back a month later. Since then, things have changed they don't have PM. They have an all new clone stock.

Also, keep your room conditions nice and it shouldn't show up. Of course, it did on us, so who knows. It is quite the foe! Oh, and here in the lower elevations it isn't as hard to get it as it is in the foothills or mountains.

Bayer disease control 2.9% tebuconzanole or spetracide immunox myclobutanil 1.55% both are as good as eagle 20 you just have to use more to get the same effects. The bayer use at 10 ml a gallon foliar. The spectracide use at 20 ml a gallon foliar. The bayer w/ Tebuconzanole is from the same family of chemicals as eagle 20 the trialazole class. And the spectracide is the exact same as eagle except way lower active ingredient %. Whats nice about these are you can buy them any were without a special license. I only use in veg or 1st week of flower.

Mildew IS NOT systemic. It is a spore borne disease. There were some here in their own mildew threads claiming that it is systemic. They are wrong and passing around bad information.

But why do you ask?

If you have it, kill it. If you don't, prevent it. Elite, Bayleton, Flint, Eagle, Rally, Pristine.... et al are all fungicides. I'm sure you can get Eagle. You'll need a permit to get the others or a friend in the Ag business.