Phrag Problem

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Chas

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A problem is spreading rapidly through my phrag collection.

(1) New growths start out green and healthy until they are about 4 - 5 inches tall and then they develop a sick yellow or yellow brown coloration and stop growing.

(2) Center new leaves of mature plants are developing areas having a light yellow coloration and then turn brown and the plant growth declines.

(3) Some leaves on mature plants and seedlings develop ugly black V shaped marks (both sides of leaves).

These problems do not appear on my paphs which grow in the same general area of the greenhouse. There is plenty of air movement and for years I have followed general cultural principles for phrags and have been quite successful. RO water, Ca/Mg supplements, etc - I never had any problems until recently. The problem appears to be spreading fast.

Are there any specific fungal or other issues that affect phrags (and not paphs) at such a fast rate? And how can the problem be treated?

Any help would be appreciated

Thanks

Chas
 
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goldenrose

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My guess would be a bacterial problem. Fungal could be secondary. When watering, any splash/spray of water? Overhead misters? These 2 factors could be contributing to the spread. New growth yellowing tells me to check for spidermites/insects, as a contributing factor. What are your temperatures like? Where do you live?
 

Chas

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Pictures, Phrag problems

Here is a try at posting some pictures.



This new growth was healty and green when it first appeared. Then the decline came. The three growth division of an awarded plant (Ashley Wilkes "Eric Young 4N x warscewiczianum FCC" was obtained from HP Norton who repotted it for me when he was in Pittsburgh in April 2007 (He recommended an "open" mix. Plant bloomed once, but the new growth never developed properly. Root system is excellent. Problem occurs with other phrags as well. Very disconcertng since for years I have grown excellent phrags (some got awards) and I have followed the recommended phrag culture techniques (pure water, flushing, avoiding water in the leaf axils, all cuts with single edged razors and am careful to avoid pitfalls (eg overfertilization, temperature extremes).

I water by hand (RO) for about 10 days every 3 days in the summer , fertilize with MSU fertilizer 1/4 strength about every 10 days. All this was successful in the past but something has spread to the collection of PHRAGS ONLY. I tried Phyton 27 but see little if any improvement in the plants. Shouls I cut off the bad new growths, retreat with Phyton 27, and hope new growths develop?
 

Chas

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Partial Yellowing of mature center leaves



Mt Fallu "longifolium x Grande

Beautiful multigrowth plant obtained fro Sam Tsui. Now in serious decline.
 

Chas

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Here is the problem with black marks appearing on the leaves of phrags. Problem appears to be spreading. By the way, if the decline pattern follows, the new growths you see will soon be turning yellow. You can see a hint of this on the plant on the right. (starts out as a yellow streak).

 

gonewild

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The problem seems to be more on older leaves?
Do the dark areas appear on the older leaves or do the appear in the crown and then grow out?

What chemicals do you use?
You said you tried Phyton but...
Have you used chemicals to kill algae or sanitize any area of the greenhouse?
How do you apply Ca/Mg supplements?
 

NYEric

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Hi, can you show the underside of the leaves of the plantin the second photo. The damage looks almost like mealy/scale on that one.
 

Hien

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Lance raises the exact question I have in mind.
If you look at the leaves, the problem blotches look symetrical, so the contamination (whatever the causes: chemical, bacteria, fungus, insect [ insects can also start the fungus/bacteria lesion by provide the entry points from their juice sucking spots] start when & where the leaves were still in the folding stage)
you can see the leaves have clean interval section (does this appearance relate to time between chemical treatment, fertilizing or watering?)
Blacken leaves can be from Phyton as well.
The new bark mix could be the culprit (I had notice the tanning from the bark did kill new growths & roots from some [not all] of my plants specially if they sit in water)

The problem seems to be more on older leaves?
Do the dark areas appear on the older leaves or do the appear in the crown and then grow out?

What chemicals do you use?
You said you tried Phyton but...
Have you used chemicals to kill algae or sanitize any area of the greenhouse?
How do you apply Ca/Mg supplements?
 

Candace

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I'm going to add a few more questions to the mix. How is your air flow? Are the plants sitting near misters? It looks a lot like a fungal problem to me but it's hard to say without a close up photo of the leaves, though.
 
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Inverness

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Your last photo suggests an event happed sometime in the past, but isn't noted till the growth grows out. I've seen damage like this from pesticides trapped in the new growth; but you don't see it till some time later. If what's happening occurs quickly over the whole plant, you'll need another opinion. Also, my experience is that many otherwise "safe to use" chemicals can have very different results if mixed with RO water.

Ken Brewer
 

gonewild

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I've seen the "V" shaped black mark as a result of fumes from Physan 20 on small phrag seedlings. That is why I asked about chemical use. The book matched black patterns indicate the damage happened while the leaf was still coming out of the crown and not unfolded yet. The very new growths in the last picture looks clean.
Need to know more about past chemical use.
 

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