Phrag Grande - Erwinia?

[My Green Pets]

I posted earlier about a Paph with leaves browning from the base.

Here is a Phrag Grande starting to do the same thing. Does it look like this is Erwinia as well? The two plants are at least ten feet / 3 meters apart...with lots of plants in between...yikes...

 

[troy]

I'd pull those 2 leaves and treat the area with fungicide

 

[Erythrone]

Yep... Erwina... A bacterial infection BTW...

 

[eteson]

seems to me erwinia. smell it if it is erwinia it will smell like rotten potatoes.

Cut the complete growt (fan) and drop abot 10-15 drops of dragon blood over the exposed surface.

 

[mrhappyrotter]

A lot of these primaries with one of the caudatum-type species in the parentage can still handle very wet conditions like the other other parent, but there are specific clones/varieties that seem to be a little more prone to these kinds of infections when grown wet.

After removing the infected material, cutting far enough back that you only slice into healthy tissue, sprinkle with cinnamon, sulphur, or other similar treatment to prevent reinfection. Reduce watering and increase air flow. If you have it, and are willing to use it, maybe treat with systemic fungicide.

I have a caudatum hybrid that I always struggle to find the right moisture balance with, and it's very prone to and periodically suffers from, similar infections. If it's Erwinia, there will be a distinctive odor of rotting vegetable material and fermentation. I basically only water this plant (and its divisions) when I water the paphs, and I never let it sit in water or allow water to sit on the leaves.

 

[My Green Pets]

I think I may have a reason for two of my plants coming down with this about the same time.

I normally keep a bucket of fresh water in my shade house for mixing fertilizers or bug spray or whatever. Well, I let this bucket of water sit and fester for a few days out in the summer heat we had a couple of weeks back.

I used this water more than once to hydrate / fertilize / apply insecticide to my orchids.

I wonder if bacteria had multiplied in the water and then got poured onto my plants? If this is the case, any number of my orchids could show symptoms. Perhaps the wettest ones are the most susceptible, like the Paphs, Phrags, Phals, and *gasp* Bulbos...omg...

 

[phraggy]

For what it's worth I had the same problem on one of my grandes, I removed the leaves which looked infected, took the plant out of the pot and got rid of the media.Made up a solution of household bleach ( tbls per gall ) and dipped the whole plant in for around 30 seconds. The plant is now ' clean-as-a-whistle' and this method can be used for any bugs or diseases without affecting the plants. Ed.

 

[My Green Pets]

phraggy...thank you! How many tablespoons per gallon / milliliters per liter (whichever!) would you recommend?

 

[phraggy]

Sorry I missed the dosage out. I use one tablespoon per gallon stirred well.
Please let us know your result.
Glad I can help --- and it will save the ones who use it quite a bit of 'dosh'

Ed

 

[John M]

Phraggy, please correct me if I'm wrong; but, I assume that's an Imperial gallon (4.55 litres), not a US gallon (3.8 litres). Thanks.

Troy and Mrhappyrotter; Erwinia is a bacterial infection, not fungal. Advising anyone to use a fungicide is of no help whatsoever as a treatment for bacterial infection. If you want to kill a bacterial infection, you must use a bactericide (which is topical), like Physan, H2O2, or even alcohol. Or, use an antibiotic which is systemic; but, I'm not aware of any systemic antibiotics for plants (while there are numerous systemic fungicides; but, as I said, they don't kill bacterial infections). That's why when our plants have a bacterial infection like Erwinia, the first action is to surgically remove the infected tissue completely.....because the treatment cannot get inside the tissue to treat it from the inside - out. Then, spray the plant with a topical bactericide to help prevent re-infection at the wound site. Also, you must attend to changing the environmental conditions that allowed/encouraged the infection to thrive in the first place. That means possibly increasing the light and/or increading the air movement and/or admitting more fresh air and/or lowering the humidity and/or adjusting the feeding schedule, or the nutrient ratio. Also, if the temps are too warm, lower them. If they're too cool, raise them. All of these environmental conditions affect the stress load on a plant. The more elements that are out of whack with what the plant wants, the more stressed the plant becomes and the more susceptable the plant is to invasion by all infection agents/pathogens. The Erwinia bacteria is EVERYWHERE. There is no point in wondering why a plant in one location and another 10 feet away got an infection. The pathogen is all over all the plants inbetween, as well. What gives rise to the infection is the genetic tendency of the plant to be susceptable, the general health/stress level of the plant and the environmental conditions, which can help or hinder the plant....as well as they can help or hinder the infection pathogens.

Attending to all these things and closely monitoring how we care for our plants is what makes us "Slipper growers" instead of "Slipper consumers". But, at the VERY least, learn the difference between a fungicide and a bactericide and choose the CORRECT treatment, if you actually want good results.

I also advise to then spray the entire plant with Aspirin water (one 325 mg tablet disolved in 1 litre of water). The ASA does not kill any pathogens. However, it does boost the plant's response to the infection and it helps the plant fight off the infection itself. In combination with increased air movement, I have found this to be the best way to halt Erwinia and save the most plants.

 

[phraggy]

Hi John. Yes I'm talking about an imperial gall. The gallonage wether UK or US
wouldn't make much difference --- this is just a remedy I got from a vegetable, plant and orchid grower of many years. He said that even the veg seedlings respond well to this method. I've used it at double dosage on cattleyas I found with mealy bug and scale with 100% success clearing the problem.

Ed

 

[Erythrone]

Erwinia is a bacterial infection, not fungal. Advising anyone to use a fungicide is of no help whatsoever as a treatment for bacterial infection.

oke:oke:oke:

 

[John M]

Thanks Phraggy. I'm going to do a test on some plants. It sure does sound like an easy way to topically treat plants.....and I'm especially intrigued at the use of a bleach solution dip as a quick and effective treatment for a stubborn case of mealies or scale.

 

[Secundino]

I have used this bleach solution as Phraggy has explained in this and other posts in this forum with my new Phrag. Cardinale. It had - first time for me with orchids - a little shoot affected with Erwinia. I feared for the healthy roots in contact with chlorine. I did the treatment two times with three days in between, and the plant looks healthy, the roots maintain their growing tips and the second, healthy shoot is visibly growing. No erwinia-smell any more, nor any spreading brown-orange spots.
It really seems to work.

I'll try it against mealy bugs and scale tomorrow (Cattleya-hybrid).I'll tell.

 

[My Green Pets]

I did phraggy's bleach dip this morning on both my maudiae-type paph and my phrag Grande.

On the Paph, I removed the offending growth and one growth on either side, taking off three in total. Then I soaked in bleach water and repotted in fresh media.

The phrag was a tougher situation. I couldn't tell where the infected tissue stopped and where healthy tissue started. There were spots and streaks at the base, at leaf tips, all on different growths.

I removed what I thought was infected tissue, the obviously browning leaves for example, then soaked the whole plant, in the pot, media and all, in the bleach water.

I don't guess I'll be surprised if this doesn't cut it, but I guess I'll just have to wait and see.

In the mean time, I bought some pool algae eliminator today that has similar ammonium chloride ingredients to Physan 20 (however the numbers are different). I used 2 tsp/gallon as a disinfectant spray all over my growing area; tables, plants, pots, everything.

Now I guess it's just a waiting game...fingers crossed!

 

[troy]

What about tea tree oil? Thats a natural antibacterial, fungicide, germicide

 

[Happypaphy7]

Fingers crossed!

Next time you see any wet brown area, you want to cut off the affected part immediately.

I'm curious to hear the report of Secun's trial of bleach solution to kill those bugs.

 

[Happypaphy7]

Hi John. Yes I'm talking about an imperial gall. The gallonage wether UK or US
wouldn't make much difference --- this is just a remedy I got from a vegetable, plant and orchid grower of many years. He said that even the veg seedlings respond well to this method. I've used it at double dosage on cattleyas I found with mealy bug and scale with 100% success clearing the problem.

Ed

Great piece of info, thanks!

I just found some soft bodied brown scales on some plants.
I have them!!! I should try this. So I guess the bleach solution penetrate the shells of the scale bugs.

 

[Happypaphy7]

Thanks Phraggy. I'm going to do a test on some plants. It sure does sound like an easy way to topically treat plants.....and I'm especially intrigued at the use of a bleach solution dip as a quick and effective treatment for a stubborn case of mealies or scale.

Me, too!
and if it is indeed effective against these annoying bugs, then there should be no developing of resistance to the bleach solution? Wouldn't that be nice?

 

[daniella3d]

Agristrep is a systemic antibiotics for plants (streptomycin). I am treating a bunch of japanese iris with scroch because the bacteria that is responsible for scorch is inside the plant and cannot be cured with bleach or what ever outside treatment. I think it also treat erwinia.

For bugs, one treatment that I always wanted to try is CO2 gas (with dry ice) in an air tight enclosure. That surely get any bugs killed and is even great for the plants (treatment must be done outside!)

but, I'm not aware of any systemic antibiotics for plants (while there are numerous systemic fungicides; but, as I said, they don't kill bacterial infections).