Grey discoloration on stalk of plant

[Sag3]

Hey, checked my indoor grow today, noticed there is this grey discoloration on the stalk of a plant.
Any idea what this is? The part attached to the grey mold like stuff slowly dies .

I've seen this before on an outdoor crop, but never indoor .
The plant in the picture has been removed from the room to prevent potential spread

Any help would be appreciated,
Thanks

 

[GrowHobo]

Looking a little like some kinda pythium. Root or stem rot. I had thought it usually starts at the base of the plant though. Is that partially attached. Could be your source. Looks like it’s fuzzy. I’m not really sure though. Hopefully somebody will pop in with a more definitive answer.

 

[Sag3]

That was my first guess, the plant affected has had wet feet for the past three or 4 days straight, (due to my employees) .
Also the plant in question is the last batch of Mandarin Cookies strain that is pm immune but seems to be suffering with a virus. Stunted growth, mosaic leaves etc etc.

 

[mancorn]

This is botrytis (grey mold). You can use a fungicide (over entire plant) and spot treat with isopropyl alcohol. (Don’t spray the leaves with alcohol, just the stem.) A lot of times the stem will die off as it can no longer get water past the effected area which will turn a tan/white color. (On a large plant the first sign is a wilted branch, where on closer inspection you’ll find the mold.) It’s best to remove the entire branch, but may not be practical if it’s the main stem. The absolute safest remedy is to discard the plant if you need to protect a larger grow.

 

[Sag3]

This is botrytis (grey mold). You can use a fungicide (over entire plant) and spot treat with isopropyl alcohol. (Don’t spray the leaves with alcohol, just the stem.) A lot of times the stem will die off as it can no longer get water past the effected area which will turn a tan/white color. (On a large plant the first sign is a wilted branch, where on closer inspection you’ll find the mold.) It’s best to remove the entire branch, but may not be practical if it’s the main stem. The absolute safest remedy is to discard the plant if you need to protect a larger grow.

You're certain? I only ask because I have been spraying this room routinely with Lost Coast, and have never had a problem with botrytis in the past ,
Also when you look up grey mold on stem there are zero pictures that look like what I have .
I'm not saying you're wrong , I hope it is botrytis because that's an easy fix , I just want to know if you're certain , like if you've had it before

Thanks for the reply

 

[mancorn]

Yes almost certain. (I’m been growing outdoors for 40+ years and definitely had my share). What can happen is that the mold will start and it looks like a grey fuzz, but after you spray it with a fungicide (or alcohol, whatever) it will knock done the mold. But the stem won’t heal (i.e. turn green again). But it will stay the tan color (basically looks like a dried up stem) and have the black dots. I’ve also treated it with hydrogen peroxide and it will look just like yours for a couple days and then the grey fuzz will return - which suggest that it’s systemic within the stem and the H2O2 burns off the mold on the outside but doesn’t actually kill the botrytis. The alcohol on the other hand almost always knocks it back. I’d suspect that the Lost Coast has also knocked back your infection. If so this area shouldn’t get any worse, but as mentioned will always look like it does now.

Do a Google search on grey mold stem and you’ll see a bunch of pics like this. Then just imagine what it would look like if you wipe off the fuzzy mold, and it’s just like what your stem looks like.