Yellowing "leaf" on my Dendrobium...

[Tetra73]

Any idea why only this particular leaf is having this yellow discoloration and with the brown patch? As I remember, the brown patch wasn't spreading 7 days ago when I got the plant.


nybg_ by vracing, on Flickr

Also, being new to dendrobium, I am not sure where are the new leaves would be growing from since the tip of canes (have 4 in total but only 3 of them look like the one in picture) appears to be some sorts of dead plant matter??? I am expecting the new leaf would overlap the previous one. One of the matured canes does not have this little light brown tip. In fact, new leaves are growing from it overlapping.


nybg__1 by vracing, on Flickr

[iHeartOrchids.com]

Unfortunately, I don't know anything about Dendrobiums, but could it be sunburn with too much light?

How are the roots? Just trying to help!

[pipsxlch]

To me it looks like the leaf in the 1st picture will be yellowing and dropping. It may be that the leaf was injured enough for the plant to want to cut its losses, it may be the plant 'choosing' to drop some older leaves as a stress response, it may be just natural senescence (hard to tell in the pic, but it does look like it may be an older leaf on an older pbulb).

Second pic- that's a normal finished growing mature pbulb. The little nib at the top is normal. It sounds like your newest pbulb is growing nicely!

[rbarata]

hard to tell in the pic

Yes, a pic of the complete plant would be helpful.

[Tetra73]

Here is an update. Is a bacterial brown rot on leaves. This wasn't the only leaves and there were several. I ended up cutting the one in the picture. For the others, I ended up trimming the leaves and to seal the wounds with some cinnamon powder. Apparently, my grow tent environment was too humid without enough air circulation AND I misted the leaves heavily. So, the bacterial brown rots were getting onto my dendrobium leaves.

Is stopped now.

---------- Post added at 05:24 PM ---------- Previous post was at 05:22 PM ----------

Originally Posted by pipsxlch

To me it looks like the leaf in the 1st picture will be yellowing and dropping. It may be that the leaf was injured enough for the plant to want to cut its losses, it may be the plant 'choosing' to drop some older leaves as a stress response, it may be just natural senescence (hard to tell in the pic, but it does look like it may be an older leaf on an older pbulb).

Second pic- that's a normal finished growing mature pbulb. The little nib at the top is normal. It sounds like your newest pbulb is growing nicely!

Yeah...I figured out that the shortest canes with the brown tip are in fact the old growth. There are 3 of them. The new growth is over 12" tall with new leaves growing.