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Fusarium Spp.

C

chris harris

Awesome info guys. Chitosan does sound interesting, I doubt that it would be that easy to eradicate fursarium with it though, as well.. I believe it is systemic, but must be air borne as well, as it's classified as a fungi, which would involve spores. I see one paper even recommends burning all plant material during cleanup.
Positive pressure in growroom is great idea, for those exact reasons, maybe even run a sealed room.
As for H2O2, I ran 1.5 ml/ L for every feeding, and it did nothing. Probably would need extreme concentration levels to work, which would kill the plants.
Even though I'm not dealing with this pathogen anymore, I'm interested in this info. Thanks again.
 
It's definitely airborne. When this problem was beginning, a tray of clones after rooting (the dome stayed on) had gorgeous white roots. Took the dome off, next day brown root tips and the downhill slope began for them.
 
I had lab confirmed fusarium spp oxysporum. Fusarium oxysporum is systemic / clones from infected mom will always have it.

Crazy thing is, plants or mothers that are infected in veg don't look that bad, they will just never get that healthy dark green / shiny look to the leaves. Usually decline in plant health will start rapidly around week 3 in flower on infected plants.

I fixed my problem by spraying a pure bleach solution on the walls / mopping the floor with pure bleach. I heated room to 150f for about 45 mins after the cleaning. Painted all surface areas with zinsner.

Switched to organic growing principles and problem pretty much went away. I have noticed that having healthy plants at all stages is the most important, and it starts with your moms. Most growers don't put the effort in to keep moms in tip top shape.

Dip healthy cuttings in a strong mycostop solution before you even plug them into rapid rooters. Make sure your not just 'organic' but your soil is balanced as close to albrecht ratios as possible. Give your plants the trace minerals it needs in the soil or by foliar spraying..zinc, copper, manganese etc. Try not to let EC drop or fluctuate to much- keep things stable.

I used Em1 a lot at first but switched to weekly Tainio spectrum drenches since it's got all kinds of different beneficials instead of just lacto.

I can definitely vouch for keeping everything healthy being the most important aspect. This all started when I left one of our locations for 3 weeks to work on upgrades to another and trusted when I was told everything looked great when I called for updates. Came back and everything looked like s**t. It spread from there to the other locations. I knew something was wrong I just did not know how serious it was till recently.
 

doneit

Active member
Veteran
Frankie...
Any luck finding a good source for the chitosan??

Also... how do you think it will affect beneficial bacteria like Caps???
 
Have you tried the physan 20 in the res all the time?

I don't have pathology but I have all your symptoms and without the physan my plants completely self destruct by mid flower.

I think genetics are important too I have one strain that is completely unaffected
 
Doneit if you are going that route get Empress Intrisnic and not Pageant. Pageant is a mix of two fungicides only one of which is for fusarium. Empress has that one ingredient but in far higher concentration. Yes it is effective. But it wont cure your problem.
 
Hey king oscar, I've never ran full on hydro I've always used substrates so I can't speak for it working for me or not. I do know that adding physan or zero tol drain to waste had marginal effect, but that was only applied every 3-4 days when they needed to be watered.
 

KONY

Active member
Veteran
What sorta lab did you use to confirm this? We dont have county extension agriculture labs here. Ive been having these same symptoms for too long, been able to get by, but not ideal. Some strains are much more effected than others.

Keeping plants 100% happy their whole life seems to be key like you guys already mentioned. I miss my old plants.

I been using chitosan for the last ~18 months. Not sure it really does anything, especially as I already use Crab Meal and Lobster Compost.

edit: also one thing to consider in your OP, is that 2 of the things you listed are systemic, and 1 of them is only translaminar.
How long they last in the plant is the more important question. Which I do not know. But if you are only root drenching, and the problem is only in the roots, it seems non ideal with cannabis to use systemic products of this nature.
 
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The lab was Waypoint labs in Los Angeles, CA. $120 for every 2 samples and they do a full profile for every known pest and pathogen. Results within 7-10 days. They are very professional and helpful.

Systemic is what you need for a problem like this. Contact you are wiping out the surface infestation. Systemic is what will actually protect it from spreading further in the plant.

To the best of my knowlodge Azoxystroublin (Heritage) Pyraclostroublin (Empress) and Thiopanate-Methyl (Clearly 3336), and I apologize for the spelling errors, those are all local systemics, as in if you apply to the root zone, it will not travel throughout entire plant. Same principle for foliar. Very few fungicides are true systemics (amphimobile I believe is the term). And of the amphimobile fungicides, none target fusarium. Root drenches are the only method of targeting this pathogen (at least as far as chemical or biological control). Physical and environmental controls of course are different.

And yes fusarium is sneaky. For us plants did not wilt in flower. Just lack of vigor. If we had not been hitting high numbers and had perfect plants before this, we may never have noticed. I truly believe alot of people have it to varying degrees, they just have it suppressed enough to where it does not destroy the plants, just limits them.
 
Just an update, got Candyland, Superglue, Sour Tangie, Tahoe OG, OG Kush and a couple others started today. They were all innoculated with microbes and put in soil and will be getting nutrient teas instead of bottled nutes. UV sterilizers at the end of every RO unit. Also rearranged rooms so now there is positive air pressure. Fungal spores and pests can not get sucked into the environment. All incoming air is routed through Hepa filters and then pushed out and gaps and cracks in the rooms along with the old exhaust vents. Praying that's the last I'll see of this.

Spoke to a very knowledgeable fellow grower we work with who experienced this. He as well had to bleach and destroy everything. Says it does not come back as long he keeps plants healthy and grow environment clean. Seems like once you've had it you're more "at risk" however. Saying that, I heated those rooms up to 150 F, the ozone levels in there got up to 65 PPM for 10 hours which is 3 times the quantity and 30 times the length of time required to kill fusarium. Then Zero Tol 2.0 spray every single nook and cranny, every single piece of equipment same treatment. I don't think there's anything more anyone can do as far as disinfection lol. We even had everyone who has access run ozone generators in their car to kill any old spores. The rest is in the hands of the cannabis Gods I guess lol
 
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KONY

Active member
Veteran
One of the weirdest things about this problem for me is how it really prefers certain strains, others are 100% unaffected. GSC Forum cut for example. The cut I have of gg4 is almost entirely resistant to it too. My chemD cut seems resistant as well.

However I have a cut of stardawg (guava) that is highly susceptible, same with the cut of bubbakush I got. The bubba cut I dont really care about because it's not real bubba kush, however the guava used to be my favorite cut. It has the potential to be really amazing, and I havent seen it do that in almost 2 years.

Frankie, the problem with the chems you listed, is they are systemic and not designed for even edible crops, not to mention smokable ones. There is not much documentation of how long these pesticides hang around in the plant.

Besides if the problem is really Fusarium, and the soil version, while the spores may be in the environment, the roots/crown is the area of the plant that actually needs treated. Theres no reason to treat above the soil line at all (If the problem is fusarium).

I'd rather not poison myself and others in the name of profit or "surviving" as others would say. With that said I would really like to see some soil half lives for these chemicals.
 
I think there is some confusion here. The systemics are applied as a root drench. You cannot apply these foliar and expect them to combat fusarium. That is not how systemics work. And I share your view on chemicals. However these systemics were used on the mother plant. Very little if any travels to the foliage. Thats the difference between a full amphimobile systemic and a local systemic. Secondly, if used on mothers, with little to no residue in the foliage, by the time that clone has grown into a 2 foot tall plant before its even in flower there is nothing left. We had over 20 lab tests performed on that scenario. So I do have documentation on how long it remains in the plant. However I am not advocating the use of these even if used responsibly, as it was not effective. And I agree 100% on GG4 being resistant. The rest were far less so.
 
C

chris harris

I was reading a gardening article on growing ginger in Hawaii. Apparently they were dealing with Fusarium. In the article they mentioned that it can stay active in soil for 10 years.
 

KONY

Active member
Veteran
I think there is some confusion here. The systemics are applied as a root drench. You cannot apply these foliar and expect them to combat fusarium. That is not how systemics work. And I share your view on chemicals. However these systemics were used on the mother plant. Very little if any travels to the foliage. Thats the difference between a full amphimobile systemic and a local systemic. Secondly, if used on mothers, with little to no residue in the foliage, by the time that clone has grown into a 2 foot tall plant before its even in flower there is nothing left. We had over 20 lab tests performed on that scenario. So I do have documentation on how long it remains in the plant. However I am not advocating the use of these even if used responsibly, as it was not effective. And I agree 100% on GG4 being resistant. The rest were far less so.


I didnt realize you were only using these products on mothers. Just reread your OP and it said it right there.... This problem + crappy weed legalization has really gotten me down over the past year, cant even read efficiently haha. Sorry about that.

I am looking for something I can use on plants a few weeks before flower. Have you tried Rootshield WP? With just Chitosan, Aloe and keeping them mostly happy I am able to harvest plants with 15% cannabinoids, I never got these tested in the past, however I am sure they would be well over 20. Im getting them to have some terps at harvest now, but nothing like I used to get.

At the same time my veg room hasnt been as happy as It could have been. Now that's back in order, I'm curious how the next rounds will turn out. Sucks cause cant really tell if anything is fixed till few weeks into flower.

edit: Upon reading this, sounds more like I have the form of fusarium wilt;

https://www.nap.edu/read/13278/chapter/7

"F. oxysporum causes vascular wilt, as exhibited by leaf yellowing, loss of turgidity, necrosis, wilt, and plant death."

Although the last 2 things dont really happen unless you count the lower leafs yellowing and dieing off as wilting, I guess it sorta is, not really sure.
 
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It could be wilt, it could be root and crown rot. Root and crown rot can cause the plant to wilt severely due to lack of ability to uptake H2o and nutrients, so it gets confusing lol. As far as I know fusarium wilt causes the plant to remain wilted. Fusarium crown and root rot the plant will recover during the night, (partially) then go through the process all over again while gradually deteriorating.
 

bigleek

Member
ICMag Donor
have a look at thirum we grow alot of leeks and onions
always damp conditions this really helps
another one is highvic

bl
 
Hey big leek thank you for the input. I have looked into thirum in the past but reading about the hazards and also its difficulty in obtaining (did find concentrated crystals on ebay but didn't really want to play around with it) I never tried it. I did hear it is pretty effective against fusarium though. I believe the old rootone cloning powder contained 0.4% thirum as one of its ingredients. Was discontinued in the US although its still available in canada. Was looking into that for using while cloning but haven't tried it yet.
 
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