When I got home, both the top and root sections of the seedling that was bitten in half were dead. But as it turns out, I might have been able to save the top with Rootone.
A week or so later, the bottom half of another seedling had turned to mush. I pulled it apart, scraped the firm tissue lightly with my thumbnail to remove most of the dead tissue, then jabbed the stump into powdered Rootone. I let it sit overnight, then planted it the next morning. I wasn't expecting anything (I didn't even try to knock off the excess powder), I just couldn't throw it away.
Yesterday I potted up all the Adenium seedlings, including the stump. It had healed, and had a root about ¾" long. It's the seeding in the photo in the red circle, photo taken yesterday before potting them up individually.
It doesn't look like it has a caudex from the angle of the photo, but it does. Being only half a caudex, it is just short, only about ½" tall (not counting leaves).
Another positive, the seedling in the green circle is variegated, so I still have one. The first several true leaves are more white than green, so the seedling hasn't grown much. The latest leaf is more green, and already it is noticeably larger than the other leaves, so hopefully growth will pick up.
The red/white picotee parent didn't set any pods this last heavy flush of blooms. It is getting buds again, so this time around I'll have to try hand pollinating. I want more variegated seedlings!
