Lets Talk About Rust Fungus & What You Need To Know.

ruffrider

Active Member
What Is Rust Fungus?
Rusts are plant diseases caused by pathogenic fungi of the order Pucciniales(previously also known as Uredinales). About 7800 species are known. Rusts can affect a variety of plants; leaves, stems, fruits and seeds. Rust is most commonly seen as coloured powder, composed off tiny aeciospores which land on vegetation producing pustules, or uredia, that form on the lower surfaces.

How Does It Spread Infection?
T
he main cause for Rust is night time temperatures being too cold with a high humidity.
Rust fungus produce asexual spores which are spread like wildfire by water, wind or bugs. Pathogenic fungi are biotrophs meaning they take the nutrients they need directly from the plants cell tissue. Once the spores settle on a plant hydrophobic interactions are formed on the plants cell surface through a process that isn't fully understood yet the Rust fungus produces a sticky like substances which attaches the spore to the plant. Once attached to a host plant the Rust fungus spores germinate by growing a "germ tube" eventually reaching a stoma, once inside the hyphae tips flatten out to lock into cell walls. A "peg" then grows into the plants mesophyll cells its creates specialised tips "Haustorium", they spread around cells without affecting the membranes. The plants membranes invaginate around the haustorial forming a open space. Iron & phosphrous rich neck bands connect the plant and fungi known as apoplast which prevent nutrients from reaching the plants cells, its grows until its produces new spores which is repeated every 10-14 days.


Prevention.
Currently there are 2 or 3 types of Pathogenic fungi which are resistant to sterilization. (Bleach washes, Sulphur Candles, Soapy washes etc.). One of the best preventions you can take in your grow room is to have proper temperature, ventilation and always disinfect your room after every grow. Spraying plants 1 or 2 a week with some kind of fungicide (I prefer Sulphur based) is also great since it reduces the changes of spore germination.

Cure
Its extremely hard to get rid of once you got it most fungicides with help slow it down but not kill it completely. At this time the only way to cure a plant once Rust fungi has gotten hold is with Systemic fungicide which runs through the plants cells killing any fungi it comes into contact with, which also can be bad since it will kill helpful fungi as well. Any infected plant material should be burnt or put in a garbage bin outside of the home as composting and leaving it a normal garbage will just spread the infection more.

If you think you noticed Rust fungi act right away because the more time it has to establish the harder it is to get rid of!

Thanks for reading!

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I recently decided to write this after I was hit a Rust fungi attack in my last grow. At first I thought it was a Mag/Cal as I experienced the same symptoms yellowing drooping leaves, browning at tips and edges etc. So I do what I normally do hit them with some Epsom salts/Egg shells which usually works like a charm to my surprise 2 days later they looked even worse so I gave them some Epsom again and samething. So I headed on over to Google and RIU of course trying to figure out what it was threads/links I could find suggested that it was just a Cal/Mag deficiency but I thought other-wise, so after browsing the net for 2 days I actually come across a forum about Rust fungi and boom thats what I had there was next to no information about. So I wrote this hoping it would provide easy/more information about the Rust fungi & Marijuana and open some more eyes, as I've seen self proclaimed experts mislead people saying its Cal/Mag deficiency, when its really Rust fungi.
 

BigEasy1

Well-Known Member
If you rub this fungus will it come off on your fingers? Some of your pics look somewhat similar to the problem I'm having but not exact.
 

ruffrider

Active Member
If you rub this fungus will it come off on your fingers? Some of your pics look somewhat similar to the problem I'm having but not exact.
From what i've noticed no it doesn't rub off on your hands, but the spores could be to small to feel so it could quite be rubbing off just im not realizing it.
 
I have something that looks like the pictures posted above. Of 4 plants, 2 have a severe case, one not so bad and the forth (a different strain,) not at all. They share a tent and overlap and contact each other. I can not get rid of it, but the flower production looks ok. Once infected, the leaves live for awhile, but eventually start to get crisp and die. I am starting to cut the bad leaves when they start curling. The other symptom that is also distressing is that the plants are stunted. I am trying to nurse them along till harvest. 7 weeks of veg and 4 weeks of flower is too much to give up on. The good news is that the 4th plant looks like it should be on the cover of a magazine.
 

Vindicated

Well-Known Member
I get this on my rose bushes from time to time. I usually snip the effected area and spray a sulfur dust. Haven't had this on my cannabis plants yet but I'm sure it's just a matter of time.
 

Rancho Cucamonga

Active Member
wow ive had this problem before also and mistaked it for cal-mag. thanks
Cal deficiency and pH issues can be similar looking to this. If leaf is crispy or dry, which usually is the case with Cal def. or pH issue it's not rust fungus. I have a few leaves that look like this in most my grows and they tend to be near the bottom and it has never spread.
 
Man i have this problem but mines not as exact theres more -_- sadly my leafs are dieing and get crusty they crumble when i touch bt not all leafs are like that just some , i have these weird flys around my plant and even saw some on it 0_0 there black or dark colored flies and they seem to be all over the place i got sum fly traps bt dosent help seems that my plant is more of a fly trap i cleaned off the bad leaves water like always but theses flys keep coming back and now there coming from a plant of mine 1 of the 4 from the soil ..... im at the point of gettin realy worried help anyone ?
 

xGrimace

Well-Known Member
Most people say this is cal/mg def but ive seen this before and it actually looks like rust spots has gotten onto your plant.
 

trontreez

Well-Known Member
Fuck! I think I might have this shit too. It's been cold and humid the last few days. I also sprayed with pyretherum a week ago for aphids so I'm hoping it just burnt for them. What do you guys think ?
 

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Nizza

Well-Known Member
Hmm everytime that I've had this problem its been a micro def . I just give it some all purpose micro nutes and it stops it. Looks like copper def so what I did is flushed the soil and gave a fresh dose off nutes n micros
 

Dendrophilly

Well-Known Member
I think my roomates house plants are infected. I'm going to clean them up and repot them.

Any of these pics look like rust fungus?

IMAG1505.jpgIMAG1504.jpg
Same leaf there, with and without flash
IMAG1499.jpg
 

VX420

Active Member
I would think if you had a fungus you would be able to wipe some of it off the leave. There are ALOT of probelms that look like the OP. Lack of P looks like that.. Not saying its not as claimed, I have had no experance with it myself. I just think if you had a fungus Like all other fungues you could wipe some of it off.

Looks like I have some reading to do.

From the OP Post;

Rust is most commonly seen as coloured powder
 

Randm

Active Member
I've been battling this for over a year! I've bleach cleaned my grow and flower rooms, used sulfer burners, and tried every trick I can think of to make it go away. And still it comes back. I too thought that it was cal/mag at first, or potasium def. When I posted picts to the forums that was the response I recieved from other growers as well. I wasted a lot of time and money trying to treat it as as deficiancy rather than as a fungal attack.

Currently I am trying a copper based anti fungal treatment, with limited success. I am going to get a sulfer based treatment in a few days and try that as well.

This is becoming such a problem that I am losing sleep over it and am near a nervous breakdown! I would like to see a sticky by somebody who has had any kind of success in battling this thing, as there is very little info out there on fighting it.

Treatements that I tried, and am currently trying are:
Actinovate - no help at all, very expensive
Seranade Garden Saver - seems to slow it down. Am still using it.
A Copper based anti fungal solution made by Ortho - Using it along with the Seranade.
Removing any infected leaves and keeping the area clean along with the above mentioned treatments.

Anybody ele who has battled this BORG please chime in and let us know what works, what doesnt work etc.
 

Randm

Active Member
If bordeaux does not work try Maneb, Zineb, or as last resort Chlorothalonil.
Have you used these products yourself? And what was the results? I do have a bottle of Chlorothalonil based fungacide made by Ortho but have not used it yet. It looks a little scary to me but I am getting desperate enough to try it.
 
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