johnnyblazed
Member
most cuts floating about either have powdery mildew or broad mites its a surprise when they dont have any issues
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Is Powdery Mildew Systemic?
- Thread starter Epiphyte
- Start date
N
noyd666
eagle 20 must be some toxic shit, can't buy it down here for love of money, not allowed into oz. having some pm troubles myself, got good reports on ATAK from optic folier, have some on the way. high ph water works ok for a day or two, easy to do if your health not the best.
Well, might as well contribute something useful.
Powdery mildews are severe in warm, dry climates. This is because the fungus does not need the presence of water on the leaf surface for infection to occur. However, the relative humidity of the air does need to be high for spore germination. Therefore, the disease is common in crowded plantings where air circulation is poor and in damp, shaded areas. Incidence of infection increases as relative humidity rises to 90 percent, but it does not occur when leaf surfaces are wet (e.g., in a rain shower). Young, succulent growth usually is more susceptible than older plant tissues.
Powdery mildews produce mycelium (fungal threads) that grow only on the surface of the plant. They never invade the tissues themselves. The fungi feed by sending haustoria, or root-like structures, into the epidermal (top) cells of the plant. The fungi overwinter on plant debris as cleistothecia or mycelium. In the spring, the cleistothecia produce spores that are moved to susceptible host tissue by splashing raindrops, wind or insects.
Source
Powdery mildew spores are carried by wind to new hosts. Although humidity requirements for germination vary, all powdery mildew species can germinate and infect in the absence of free water. In fact, spores of some powdery mildew fungi are killed and germination is inhibited by water on plant surfaces for extended periods. Moderate temperatures (60° to 80°F) and shady conditions generally are the most favorable for powdery mildew development. Spores and fungal growth are sensitive to extreme heat (above 90°F) and direct sunlight.
Source
Conditions Favoring Powdery Mildew
High relative humidity at night
Low relative humidity during day
70-80F (22-27C) temperatures (These conditions prevail in spring and fall)
Source
Powdery mildews are severe in warm, dry climates. This is because the fungus does not need the presence of water on the leaf surface for infection to occur. However, the relative humidity of the air does need to be high for spore germination. Therefore, the disease is common in crowded plantings where air circulation is poor and in damp, shaded areas. Incidence of infection increases as relative humidity rises to 90 percent, but it does not occur when leaf surfaces are wet (e.g., in a rain shower). Young, succulent growth usually is more susceptible than older plant tissues.
Powdery mildews produce mycelium (fungal threads) that grow only on the surface of the plant. They never invade the tissues themselves. The fungi feed by sending haustoria, or root-like structures, into the epidermal (top) cells of the plant. The fungi overwinter on plant debris as cleistothecia or mycelium. In the spring, the cleistothecia produce spores that are moved to susceptible host tissue by splashing raindrops, wind or insects.
Source
Powdery mildew spores are carried by wind to new hosts. Although humidity requirements for germination vary, all powdery mildew species can germinate and infect in the absence of free water. In fact, spores of some powdery mildew fungi are killed and germination is inhibited by water on plant surfaces for extended periods. Moderate temperatures (60° to 80°F) and shady conditions generally are the most favorable for powdery mildew development. Spores and fungal growth are sensitive to extreme heat (above 90°F) and direct sunlight.
Source
Conditions Favoring Powdery Mildew
High relative humidity at night
Low relative humidity during day
70-80F (22-27C) temperatures (These conditions prevail in spring and fall)
Source
StankyBeamer
Professional A$$hole
Good to see real credible info being perpetuated for once. Any .edu website will clarify the endocytic/ epiphytic growth. It just seems to he systemic because it reproduces rapidly and the Mycellium isnt killed by topical sprays.
If it has root like structures within the plant, could it not be classed as systemic. Since you would need a systemic treatment anyway to kill everything under the surface?
doesn't seem to be a definite consensus systemic or not?
PM is not systemic.
if it were all cuts taken from it with have it, the tools used in taking cuts would transfer it.
take a plant with PM and get a cut, spray it down with volck oil-mineral oil to take out any spores lurking on the leaves. that cut will be PM free.
btw haven't heard any mention of using mineral oil to deal with PM
it's old school, low toxicity and kills loads of other nasties from mildews/rusts/scales to pests aka spider mites white fly, aphids and plenty more,
if that ain't goodnuff it's an ovacide.
spray this on leafs tops/bottoms before bloom and it'll take care of most bugs/fungal probs
PM is not systemic.
if it were all cuts taken from it with have it, the tools used in taking cuts would transfer it.
take a plant with PM and get a cut, spray it down with volck oil-mineral oil to take out any spores lurking on the leaves. that cut will be PM free.
btw haven't heard any mention of using mineral oil to deal with PM
it's old school, low toxicity and kills loads of other nasties from mildews/rusts/scales to pests aka spider mites white fly, aphids and plenty more,
if that ain't goodnuff it's an ovacide.
spray this on leafs tops/bottoms before bloom and it'll take care of most bugs/fungal probs
indoor gro's provide the few parameters that are needed/ideal for mildews and fungi spores to germinate and thrive.
take away one of these requisites and PM cannot grow to fruition.
ime wind is the one ,most single thing we have control of to negate and that's stale air
that will keep PM at bay.
an excellent example is the fugus that attacks seedlings called damp off, it attacks the the seedlings stem at the soil line where it lives.
once you have it get some captan, it will kill it quick and easy.
the fungi cannot do the dirty deed as long as you have some air movement,
not much does the trick but stale non-moving air and enuff Rh and it'll thrive.
whenever i run seedlings I have a small 10"fan I clip on the end of the HO T5 lites so it'll blow over the babies.
I haven't had it so long i can't remember
the only time i had a case of PM I didn't run the fans
on that bloom run,
it was winter in deep south and my mind was on heat control
not mildew.
I found out real quick about PM.
since I was in bloom i was careful with application
and mineral oil wiped it out,
set the fans back up and have never seen PM again.
since those days i have fans over the canopies and more importantly under the plants where the best conditions are for PM.
lots of airflow everywhere is your best friend against PM, the best part is its free, and very easy to do.
i buy those $24 lasko 20" wind tunnnel fans from wally world $30 w/remote
and let me tell ya they can move the air!
they are also wall mountable.
take away one of these requisites and PM cannot grow to fruition.
ime wind is the one ,most single thing we have control of to negate and that's stale air
that will keep PM at bay.
an excellent example is the fugus that attacks seedlings called damp off, it attacks the the seedlings stem at the soil line where it lives.
once you have it get some captan, it will kill it quick and easy.
the fungi cannot do the dirty deed as long as you have some air movement,
not much does the trick but stale non-moving air and enuff Rh and it'll thrive.
whenever i run seedlings I have a small 10"fan I clip on the end of the HO T5 lites so it'll blow over the babies.
I haven't had it so long i can't remember
the only time i had a case of PM I didn't run the fans
on that bloom run,
it was winter in deep south and my mind was on heat control
not mildew.
I found out real quick about PM.
since I was in bloom i was careful with application
and mineral oil wiped it out,
set the fans back up and have never seen PM again.
since those days i have fans over the canopies and more importantly under the plants where the best conditions are for PM.
lots of airflow everywhere is your best friend against PM, the best part is its free, and very easy to do.
i buy those $24 lasko 20" wind tunnnel fans from wally world $30 w/remote
and let me tell ya they can move the air!
they are also wall mountable.
not true. I have seen an immune strain.
On that note, susceptibility differences amongst different cannabis varieties is huge. Some are hellish magnets, others get it only on the stem and it wont spread to the leaf at all. There are lots of different reactions to PM by different cannabis plants.
Chimera claims it's systemic, and he certainly knows more than me.
https://www.icmag.com/ic/showthread.php?t=129670&highlight=Powdery+mildew
https://www.icmag.com/ic/showthread.php?t=129670&highlight=Powdery+mildew
PDX Dopesmoker
Active member
Don't keep us in suspense, whats the name of that mildew free marijuana?
Potasium Silicate is most often in an alkaline suspension. The shift in pH causes the PM to die. The secondary effect is a tougher cell wall. So spores cannot invade as easily. But this takes weeks of feeding
No its not systemic. It spreads by spores. And they cannot grow if leaf surface pH is altered.
Eagle 20 works. But it is systemic and very bad to smoke. Only should be used in very early veg. Myclobutanil forms cyanide when combusted. So please dont fuck around with it without clear understanding.
No its not systemic. It spreads by spores. And they cannot grow if leaf surface pH is altered.
Eagle 20 works. But it is systemic and very bad to smoke. Only should be used in very early veg. Myclobutanil forms cyanide when combusted. So please dont fuck around with it without clear understanding.
Chimera later took back that systemic designation as I recall. I won't speak for him though.
Ive been told adding enzymes (enzymes komplete, for example) to the soil or reservoir can remove PM too. Currently testing that out.
Red Congo x Panama Red was immune. It could be in a room full of plants with PM, even leaning on PM, and nary a drop ever. For years. I believe some pure congos are possibly immune too from what I have heard.
Ive been told adding enzymes (enzymes komplete, for example) to the soil or reservoir can remove PM too. Currently testing that out.
Red Congo x Panama Red was immune. It could be in a room full of plants with PM, even leaning on PM, and nary a drop ever. For years. I believe some pure congos are possibly immune too from what I have heard.
