I think that any tomato can be crossed with another. But there has to be a purpose ! You want the big tomato get small or cherry tomato to get big?
Also it would probably depend on which one is the recipient. And , as I understand, it might take more than one generation of cross pollination to get a predictable outcome.
Lets say , you wand to change BS. Cross it with cherry. Take the seed from that , plant it next year and cross it with cherry again .. third year .. fourth year. THEN you might get something that is stable. I have never done this but this is what I understand.

Thanks, Seysonn.

I'm not concerned with stabilizing a cross yet. Just making the F1 hybrid. So that's not an issue.

At this point, I'm wondering if the cherry and the large fruited types are genetically compatible.

Jim

I found the book (Breed Your Own Vegetable Varieties( by Carol Deppe at my local library. Very interesting information on how to make crosses, the basics of plant genetics, etc. There is specific information on tomatoes, so you might find it helpful.

Here is a link that might be useful: Breed Your Own Vegetable Varieties

That's a great suggestion, Kathy! In fact, that is my favorite gardening book. I suspect to find an answer to my question there. I have a copy but it is currently loaned out to a friend.

Jim

You can cross the two no problem. It is easier to emasculate the large fruited parent and take pollen from the cherry, Not only will it be easier you will likely get more seeds that way, One can emasculate the cherries but it takes some patience,

What you get is something about the size of a golf ball. That depends on both parents but that is the general idea.

F1 fruits will usually be round and generally only have two or three locules when cut in half.

'Purple Haze' is an good example of what should generally happen.

The parent lines are in the background and the F1 'Purple Haze' is in the foreground.

Most tomatoes are of the common species which we normally use and are completely cross fertile. So ability to cross breed is not generally something you need to worry about. However, there are a few other, closely related species of tomatoes and these might not cross breed as easily. Most of those related species tend to be very small cherries, even "Currant" cherries, so you are unlikely to be dealing with them if you have anything like a standard cherry tomato.

When you cross a cherry with a large tomato, you generally get something in between, but it will probably be closer in size to the cherry tomato. This is because the cherry tomato is closer to the ancestral type, and frequently will have more dominant genes. However, you will get a wide range of progeny on grow outs of future generations, ranging from cherry sized right up to close to the size of the original large tomato parent.

Thanks, everyone. That is the information I was seeking. Now I just need to perfect the emasculation/pollination process. I'm having a little difficulty harvesting pollen.

Jim