Stem Necrosis?

[RaoulDuke]

I need your help! I was just inspecting my plants and found something strange... One of the side branches is dying starting at the stem and radiating out. Fungus seemed like the obvious answer, but I don't see any mold on it and the tent has low humidity and good air circulation, so I don't think that's it. Branch was not bent or damaged (that I previously noticed), it was still standing upright when I found it. I haven't seen any insects in my tent at all, so that doesn't seem very probable to me. Strangest was the pine sap like goo on a couple of the dying leaves from an unknown source. Plant is on week six of flowering. Showing some signs of a slight Mg deficiency but otherwise very healthy. It seems limited to this one spot, so I removed the affected branch to be safe. I'm stumped, I'd appreciate any suggestions on the cause of it?
:watchplant::confused2:

(Sorry for the crappy quality, all I have is a weak cell phone cam)

 

[HippyInEngland]

The second pic looks like grey fungus growing.

Fungus Botrytis

This is the most common variety of fungus found on cannabis plants. It is also called gray mold, gray blight or Botrytis blight. It begins its life as a white powder-like growth, which eventually turns gray as it spreads.

Fungus Botrytis forms spores that dislodge and are spread to neighboring plants. The spores can stay dormant for quite some time, so growers should treat all the plants in the surrounding area for Fungus Botrytis. This is because the fungus has a high tendency to stealth spread itself without notice in spore format. Spores do not need living matter to stay alive.They can lay dormant almost anywhere.
If you can solve a Fungus Botrytis problem quickly then you may prevent spores from being produced and this is why growers need to keep a close eye on their plants. Fungi are very hard to clean by hand. Rotted areas must be clipped away instead.

Fungus Botrytis will grow wherever it comes in contact with plant nutrients.This means that the fungus is more likely to be found developing on necrotic plant tissue or other damaged areas of the plant where the nutrients are more readily accessible. From here it spreads to other areas of the plant causing its feeding patches to rot. Cut areas after pruning and cloning are especially susceptible to Fungus Botrytis.

High humidity will cause fungi to spread more rapidly so lower humidity levels if needed. In some cases, lowering the humidity is all that is needed to prevent the fungi from spreading. Mold should also be treated the same way. If lowering the humidity does not solve fungi or mold problems then you need to apply a fungicide on the infected areas. Fungicides can be used on the infected areas to remove the fungus — preventing further plant rot. Spores tend to fall downwards so remove the top layer of soil from your infected plant and throw this away. After harvest, a previously infected grow area should be cleaned down to prevent further fungi growth during your next crop.

eace:

 

[RaoulDuke]

It looks like all the symptoms of mold, without any sign of actual mold itself. Would a fungus cause clear or slightly amber colored sap to drain from the plant?

 

[HippyInEngland]

Any plant with a wound or some form of attack will try to heal itself, it sounds like the plant was secreting its own defence.

eace: