I have done some research on marijuanahydro.com and I dont think I have powdery mildew. I think I have what is called Fungis Botrytis. Powdery MIldew is always fluffy white where as Fungis Botrytis is grey patches. Read this.
Powdery Mildew
Powdery mildew is a common fungus that can rapidly infect a crop. Like Fungus
Botrytis and mold it can be prevented using good ventilation and low humidity
levels.
Powdery mildew starts its life, grows and produces spores much like Fungus Botrytis, except that powdery mildew does not turn gray but stays a fluffy white color. Powdery mildew is easier to wipe off than Fungus Botrytis but tends to spread more quickly than Fungus Botrytis, causing the plant's leaves to be covered in a white film. This inhibits photosynthesis and leads to stunted growth. Powdery Mildew also rots bud.
Powdery mildew can be curbed using the same techniques used in the treatment of Fungus Botrytis.
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.
[FONT=Times New Roman, Times, serif]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.
[/FONT]