Bacterial infections.

[Nancy]

This is a matter of curiousity, but I was wondering if there are any species that are more prone to bacterial infections than others. The reason I am asking is that I purchased two Cattleytonias. The first one, Ctna. Keith Roth, I had to cut one leaf beyond a dark spot that was rapidly going down a leaf. The second one Ctna Why Not. This plant has two leaves with black spots at the tips. I'll be trimming these as well. I ust wanted to know if anyone had any ideas, thanks.

[kmarch]

Your cattleytonias are hybrid orchids not species, so is your question in reference to species orchids or your hybrids?

Either way, it sounds like your black leaf tips are possibly not a bacterial problem. I'd first suspect fertilizer burn which causes leaf tip blackening.

Do you fertilize?

[jerrymeola]

Ctna Why Not grows like a weed so I would say your problem is root related. Damage in repotting is a common cause. Overwatering will also cause rot that displays as blackening leaves.

Keith Roth has a hard time reatining water if neglected but that is the exact opposite of your sympthom.

I have to go to root damage.

[Nancy]

I just bought the Ctna. Why Not and have only watered it once. No repotting. I just divided and repotted the Ctna. Keith Roth. No root damage and the roots are growing well. I guess I was wondering if the Broughtonia in both crosses was prone to bacterial infections. I haven't fertilized either one either. I guess it all happened while they were still in the greenhouse where I purchased them. I just thought it was sort of curious.

[kmarch]

Sometimes nurseries fertilize pretty heavily, understandable because customers like to buy big healthy plants. That's not a criticism, just an observation. My limited experience (only about 10 years of growing, compared with some here on the forum who have grown for 20-30 years) suggests that being prone to bacterial problems or other orchid diseases probably has more to do with culture than with any inherent resistance to bacterial infections. Strong plants stay healthy, weak plants get sick. I had a Broughtonia species in my collection years ago (got rid of it when I moved) and it grew and bloomed in a manner very similar to cattleyatonia hybrids.

If roots are healthy, I'd suspect nursery over fertilizing or getting too dry as the culprit. I'd repot at the appropriate time and lay off the fertilizer for a while, and then if I fertilized, I'd do it lightly.

[Tobi]

Originally Posted by kmarch

My limited experience (only about 10 years of growing, compared with some here on the forum who have grown for 20-30 years) suggests that being prone to bacterial problems or other orchid diseases probably has more to do with culture than with any inherent resistance to bacterial infections. Strong plants stay healthy, weak plants get sick. and then

Kevin,
I agree with this totally. I don't believe a plants genera or specific hybridizing
makes it more susceptible to bacterial infections than any other. A plants
immune system is pretty much affected by its cultural environment. Wet
environments, low light levels and high moisture can all favor bacterial
emergence. Since the primary two bacteria (Erwina & Pseuodomonas) that
affect orchids are water borne, they can easily be transported by splashing
or moving water, contact between plants, and contaminated media as well
as carried by insects and other organisms. Thus maintaining the best
cultural care, including using sterile techniques when cutting and repotting,
can eliminate their immune system being jeopardized.

[Nancy]

I'll have to repot the Cattleytonia Why Not when it finished blooming. It has very pretty flowers. They are a deep burgundy and much smaller than type. Would the deeper color and smaller flowers be caused by too much light?

[mockingbird]

I'm not sure if my problem is bacterial but..my Nun's Orchid has brown spots on the leaves. This happened with my first one and it died. Help please. Gingerlily