Anyone know what the green blisters are on my seedlings?

[hardland]

These seedlings are about 3 weeks old and seemed to be doing quite well. I just noticed some green almost crusty spots on the back of true leaves, they almost look like blisters. The spots are on 3 of 20 seedlings, have no clue what it is. The seedlings are inside under grow lights. thanks in advance.

[applestar]

It's not easy to tell from the photos, but they really look to me like young scale insects. Try touching them with rubbing alcohol soaked cotton swab -- soak the "blister", then swipe off. If they come off, then for sure, they're scales.

You may want to mist the young tomato leaves with water after treating since the alcohol may prove too dehydrating and burn the leaves.

If they're scales, and this is just early stages, you could probably swab off all of them. Make sure to also check for darker -- olive or brown -- waxy bumps which would be the adults.

[hardland]

Thanks, I will try that. Here is a larger pic.

[hardland]

Tried the alchahol thing, did not see anything come off when I swabbed. Doesn't look like animal to me? Not sure what to do?

[TZ -OH6]

http://www.ces.ncsu.edu/depts/pp/notes/oldnotes/gp3.htm


http://vegetablemdonline.ppath.cornell. ... ma_Tom.htm

[hardland]

Very interesting, thanks TZ. At least it sounds like it is not going to spread from seedling to seedling, also sounds like I need to back off on watering a bit.

[applestar]

Yep. In the close up, I can see that the "blisters" look integral to the plant tissue and are too irregular in shape to be scale insects. I don't know that I've noticed this kind of damage to my plants before. Good to know.