Phalaenopsis with disease
 

Hello. This is my first post however I have been reading helpful posts on here for a while. I wondered whether anybody can help me? I have a phalaenopsis orchid which I have had for a couple of years. It was a rescue originally but is currently flowering and has a healthy root system. Last summer it started to develop yellow spots on a couple of its leaves which I put down to too much light/heat. However, it seems to be progressing and as a relative newbie to understanding orchids, I'm unsure whether this is something more sinister that needs treating? The older leaves are getting worse and it is also now apparent on one of the newest leaves. I have done some research but have been unable to come to a final conclusion about what it may be. I wondered about mites but when I wipe the bottom of the leaf, there is nothing on the tissue? A couple of the flower spikes are also now going black which worries me. I'd hate to lose this orchid and am desperate to know what I can do for it? I have also attached a photo of a deeper green leaf which belongs to a second phalaenopsis I have. I'm concerned about the white specks on this one and the patterning on the leaf? Many thanks, Sarah
Attachment 130798

Attachment 130799

Attachment 130800

Attachment 130801

Attachment 130802

Attachment 130803

Attachment 130804

Attachment 130805

Attachment 130806

Hello Sarah, Welcome to the Orchid Board.

I don't know what that is. I haven't seen anything like that. I hope Camille enters the discussion. She has had problems with her Phal collection in the Netherlands.

The very last photo looks like a normal mottled leaf of some orchid species and their hybrids. But the rest are sick. If possible try to isolate them from other plants.

I'm so glad you said that, ES. I was stumped too.

That's new to me, too.

I have no idea what is wrong with the first plant, if it was mine I would bin it - whatever is wrong with it seems to be quite virulent.

I have Phals with the exact same symptoms. New leaves are fine, and after a few months they start to look like that. Working at a place with a plant diagnostics lab, I had the luxury of being able to give a colleague samples from 6 different Phals, and he tested them for 6 different viruses common on orchids. All the tests came back negative... He did not do further tests for bacterial/fungal disease because it was too expensive to do pro-bono for me. (involves sequencing a segment of the pathogen DNA and blasting it against a database).

The official assessment of the lab is insect damage. I did have a mealybug problem at the same time, but not on the scale that would cause such symptoms on the plants.

After more searching on the web, I can across a french blog post of someone dealing with the same thing. Ravageurs ou Maladies - Les Orchidees de Sophie.com (you can put it through google translate).

A few ideas from the comment of that post: It can be due to mites, but not the red ones so won't show up if you wipe a leaf with cotton. They suggest treating with a miticide or rubbing alcohol with cinammon steeped in it (do not use on roots). Other possibility was something fungal that people are calling 'microfungus', and recommended a systemic fungicide such Funginex.

Not having access to systemic fungicides (Netherlands banned the sale of many chemicals a few years ago), I'm watching and waiting to see if the new leaves stay symptom free, after having treated the plants with insecticide (for the mealies) and acaricide.

If you have just one plant affected (that last photo is normal leaf mottling), I would trash it. I'm hesitant to do that because I have many Phals affected, and Phals represent the bulk of my collection. I've trashed the really badly affected plants for now.

Thanks Camille for your reply and link - its really insightful and is good to know it's not just my orchid that's affected! Seems the best place to start is to assume either mites or fungal.

I've been researching natural treatments and both cinnamon and Listerine have been mentioned as antifungal? I'm also considering treating this orchid and another with rubbing alcohol for mites. Does anyone know whether any of these treatments be done at the same time or do they need to be done separately?

I don't know if this helps but, I spray my Bulbo with Amber Listerine regularly. It does kill surface fungus in the media and plants... algae type. If it works as a systemic, I would doubt. I've never had a serious problem to experiment.

From what I've read about this mysterious disease, if a fungicide has any effect, it's always a systemic fungicide.The typical home remedies have no effect on it, it's that aggressive. The question is, all all plants with these symptoms afflicted by the same thing, or are there multiple different causes at play?

Regarding a systemic fungicide, I know that Physan 20 is popular but it is not available in UK. I've read that Bayer Rose Clear also works and is safe for orchids? Is this correct?