Loosing Oncidium leaves though treated!

[kwarren]

I need some help quickly from any kind soul who knows what to do and will take a moment to instruct me.
My oncidium intergeneric plants are showing leap tip dieback, so I took the time to unpot them and soak for about an hour in a fungicide solution using "Manconeb".
Then I repotted in sterilzed pots and new bark. I cut offf the leaf tips and/or removed completly yellowed leaves before the submersion. That was two weeks ago.
Now I am noticing that the cut ends are starting to show the same light brown dieback and the oldest leaves are turning yellow quickly.
I am afraid of losing them. Am I using the wrong kind of fungicide? Do I actually have a virus problem?
I have many more catts and have had a slight problem with leaf rot in the past but the fungicide bath and new medium cured the problem along with better light and a little less watering.
Please someone help me. I would really appreciate it.

[Leafmite]

How were the roots when you repotted? I found that oncidiums do very well in large lava rock as it allows the frequent watering they like without rotting the roots. Of course, I live in Ohio and we have humid, often rainy summers and cold dark winters so bark and moss do not dry out quickly enough. Whatever medium you select, it should dry out (bottom and middle of pot included) quickly. The medium's job is not to keep the roots wet but to provide humidity between waterings. As oncidiums don't grow in the soil, their roots need contact with air. Many people have luck mounting these on cork. Good luck!
Leafmite

---------- Post added at 01:06 PM ---------- Previous post was at 12:09 PM ----------

I had a few more thoughts on your oncidium. How is your humidity? What lighting are you giving it? Do you fertilize? Too much fertilizer, too much light, or not enough humidity can sometimes cause browning of leaf tips. My oncidiums always grew and flowered very well but they did have spots and brown leaf tips (although these didn't progress) and I gave all but my Onc. Sharry Baby away because I wasn't fond of looking at them when out of bloom. Sometimes the leaves on the oldest psuedobulb will turn yellow after a few years to become a back bulb but it is still wise to ensure that the roots are healthy. Again, good luck!
Leafmite

[Gage]

I can't say for sure, but doesn't sound like fungus if it's browning from the tips only and without any other strange discoloration. I would agree with the previous post and think about the roots. When the roots of any orchid rot and die, the plant will start letting go of leaves. If root loss is the case, the fungicide treatment will not prevent further leaf loss, only will stop fungus spread. If you get the medium right for your conditions and watering pattern, the problem should fix itself. Psb's may shrivel, and more leaves fall, but at some point it will put out new growth and new roots. Good luck!

[kwarren]

Thank you so much for taking your time to help me. I have to go to work now but will re-read your info tonight and consider what you said. Thanks again!

[King_of_orchid_growing:)]

I'll add that many Oncs are very resilient. They may suffer some heavy root damage, and yet still make a full recovery if the plant has enough energy to do it under good care.

[camille1585]

By Manconeb I suppose you need Mancozeb? Soaking only the roots will do nothing, as it is not a systemic fungicide. Best to mix it up in a spray bottle and spray the leaves directly with it.

[nlm2951]

I just lost about 25 onc.I do everything possible to take care of them, but I don't know what's going on.My friend have them with no care at all, and they are growing and flowers, now I only have 4 left, until I find out what happened I'm not buying anymore onc., I love them, but no more

[Ray]

Depending upon the particular intergeneric, they can require a whole range of different conditions. Some require higher light than others, some like it cooler than others, etc. Trying to make an assessment without know exactly what we're discussing is difficult.