Dorje113
Member
PM could certainly be systemic, the powder is just the fungus' reproductive organ and there are roots (mycelium) that extend from the powdery mold into the plant, extracting nutrients to feed the fungus. The mycelium will survive in the leaf, or possibly extend into the plants stems (some people report weaker stems with pm infected plants) despite having eliminated visible signs of infection due to use of any non-systemic fungicide. I believe it takes a systemic fungicide like Eagle 20 to actually kill off the mycelium inside the plant's tissue, otherwise it MAY (or may not) recur.
Fungus takes a build up of energy combined with the right conditions to "bloom" and actually be able to produce spores and the powder we all hate. This goes for mushrooms as well as molds. Sometimes the right condition occurs because of plant senescence (it dies at the end of it's cycle) or because of environmental conditions are favorable. The problem with the 1st scenario is that powder will show up as your plants are maturing which can ruin a crop. Also, the mildew blooms all over the plant simultaneously, it does not appear in one area and spread because IT IS NOT SPORES CAUSING THE OUTBREAK, it is mycelium that have been left alive inside the plant. This is why people report PM outbreaks when the conditions have been impossible for spores to germinate.
Once you have got rid of pm using a systemic fungicide, the plants will still be subject to spores unless you have a clean room. There's TONS of PM infected plants growing all around my house (that I need to kill somehow, or maybe Eagle them). Healthy plants and proper environments will keep the spores from being able to germinate. But they are there... waiting for their chance. I think it is harder for spores to infect a healthy plant than it is for mycelium to become active inside a plant from a partially cured previous infection, and the vector of contamination is COMPLETELY different. If PM shows up the last week of flowering it's probably been there a long time waiting for it's chance to produce spores.
I'm only speaking from my experience growing gourmet mushrooms and understanding their lifecycle. PM infection isn't as simple as most people think from what I can tell....
Fungus takes a build up of energy combined with the right conditions to "bloom" and actually be able to produce spores and the powder we all hate. This goes for mushrooms as well as molds. Sometimes the right condition occurs because of plant senescence (it dies at the end of it's cycle) or because of environmental conditions are favorable. The problem with the 1st scenario is that powder will show up as your plants are maturing which can ruin a crop. Also, the mildew blooms all over the plant simultaneously, it does not appear in one area and spread because IT IS NOT SPORES CAUSING THE OUTBREAK, it is mycelium that have been left alive inside the plant. This is why people report PM outbreaks when the conditions have been impossible for spores to germinate.
Once you have got rid of pm using a systemic fungicide, the plants will still be subject to spores unless you have a clean room. There's TONS of PM infected plants growing all around my house (that I need to kill somehow, or maybe Eagle them). Healthy plants and proper environments will keep the spores from being able to germinate. But they are there... waiting for their chance. I think it is harder for spores to infect a healthy plant than it is for mycelium to become active inside a plant from a partially cured previous infection, and the vector of contamination is COMPLETELY different. If PM shows up the last week of flowering it's probably been there a long time waiting for it's chance to produce spores.
I'm only speaking from my experience growing gourmet mushrooms and understanding their lifecycle. PM infection isn't as simple as most people think from what I can tell....
