Diverse shallots from true seeds

[bower]

It would be fun to cross them with onions..

How exactly would someone cross shallots with onions? Wait for the stalk to appear and then bag both of them? Use a q-tip on one plant to fertilize the other?

AFAIK I think the tricky part would be to get them to flower simultaneously. Put them next to one another and let the bees have at it. Then you must grow out all your seed to look for the crosses.
I've been thinking about this, wondering the pros and cons of using a hybrid onion as a parent. Typically hybrid onions are male sterile, as this is used to facilitate seed production. I need to take a closer look at the genetics of that, iirc 'cytoplasmic male sterility' is inherited through the female line, which means it would be present in the hybrid.
Anyway if the hybrid onion parent is male sterile, and you stick the flowering plant in the middle of a patch of flowering shallots (or with your favorite select flowering shallot) then the only seeds in the onion pod will be those pollinated by the shallots.
Conversely, if you're planning to save shallot seed as well, no worries about any crosses, they won't happen because no fertile onion pollen to do the job.

If that's how it works, then the issue would be, your offspring of the onion hybrid would all be male sterile, so again, you would have to cross them with something to get a new generation. You would not be able to self them to create a true breeding line.
I may be wrong in some detail, but I think those are the issues with CMS, passed on by mother plant.

There are a couple of different types of male sterility used in breeding, IDK what other issues arise or which other ones may be commonly used.
So a fair bit of web crawling required before making an onion crossing plan.

[wykvlvr]

OH now I am even more excited about growing the seeds I got...