Hi,

Your photo sent me down an internet rabbit hole in search of an answer. That only the fruit is affected is confusing; similar issues that pop up usually affect both fruit and leaves.

One possibility is that this is one of the bacterial diseases that persist in seed, which would explain why only this plant is affected. Photos of bacterial canker spots are similar to what you see; this disorder also sometimes displays as “netting” on fruit. I couldn’t find any photos as infected as your tomato. But here’s a fact sheet on canker:

https://extension.umn.edu/disease-management/bacterial-canker-tomato

How are the fruits inside? Are all the fruits on the plant like this, or is the only one? What do the leaves look like?

Hi, I’m going to consult with a U staff member. Will get back to you.

Hi again Deb,

I reached out to an extension specialist and she too is mystified. Because the fruit was fine inside, the leaves weren’t affected (except perhaps by late blight) and because the parent plants were fine, she doesn’t think this was bacterial canker. She speculated that this was some kind of growth cracking that was accentuated by the extreme heat and environmental conditions.

I’m sorry we haven’t come up with a sure answer. It’s a mystery!

Thanks.

I fear we may never have “normal” again! But we can hope. Enjoy what’s left of the gardening season, and thanks for a most interesting question.