In order to isolate a cause as most probable, you need to eliminate those least probable. It doesn't look like a disease issue, so you should probably concentrate on insects, being root bound, nutritional deficiency, light, or watering habits (under/over-watering).

First, inspect for pests. The two primary suspects would be spider-mite or scale. You'd probably notice mealybug if that was the problem. If there are no 'sticky' leaves, or the surface under the plant isn't sticky, it's probably not scale. Hold a white piece of paper under an affected leaf and tap it; then inspect the paper carefully for moving mites about as fine as finely ground pepper.

How long have you had the plant? Is it badly root bound? Ever repotted it? Tight roots cause slowed branch extension and loss of lower and interior foliage.

Have you been fertilizing regularly? with what? how often? Nutritional deficiencies will cause the plant to shed old foliage, extracting everything it can, to supply the new growth with whatever nutrients it can cannibalize from the old foliage it's shedding. Sometimes, chronic over/under-watering can cause nutritional deficiencies, and either over/under-watering can cause a drought response, the most noticeable symptom of which is foliage that looks like yours looks.

Light can also be a major issue - especially if the plant was recently moved from a bright spot to one dimmer ...... or if it was only recently purchased and is in the process of acclimating to a 'less bright' environment.

So - what rings a bell, and what can you eliminate as likely causes?

Al

The plant is quite new. I looked closely for any signs of pests on the leaves but found none. I have read about scale and that didn't fit the "feel" of the leaf. Nothing rubbed off if the leaf is wiped. I've seen spider mites, looked for them, and there were none.

The first leaf turned the day after I brought it home. Whatever the problem, it came home with the plant. Because there were fruitfly like insects around it (likely fungus gnats accordig to what I read on the forums) I isolated it immediately in a well lit spot, near a window but protected from sun.

Today I went into the room and noticed a moldy odor that triggered allergies, so I decided the plant had to go. Am just hoping the few "flies" I saw haven't found my other plants.

Thanks for trying to help. Any of the cultural problems could have happened before i brought it home and trying to rescue it was my first hope, but the moldy smell and allergy attack changed that. When I put the plant in a plastic bag to discard, the bottom of the pot was quite damp and smelly so likely overwatering and maybe rot were problems.

I'll give it another try with a plant from a different place.

Thanks for answering my request!

I agree that it could be a cultural issue that started with diminished photo-exposure before you acquired it - or even perhaps an over-watering issue that began with the plant's prior keeper. Too bad - wishing you better luck with your next acquisition. ;-)

Al