Sorry to say, but this looks like herbicide injury.

Note that tomatoes are especially sensitive to even small amounts of herbicide exposure, and other plant species may not look affected. Don't know offhand about potatoes' sensitivity to herbicides, but they're in the same family so wouldn't be surprised if they're also very sensitive.

Did you spray weed killer recently? Is it possible any of your neighbors sprayed weed killer recently (have you seen landscapers/lawn care people working in their yards)? Are you near agricultural fields (herbicide can drift a really long distance on a windy day when sprayed in the quantities used on farms). Did you apply any wood or straw mulch recently or any grass clippings from areas that could have been sprayed with weed killer? Some weed killers persist for a long time on straw or wood.

Another possibility is a virus, but if you're not seeing feeding damage from thrips or leafhoppers, it's most likely herbicide exposure.

My neighbor sprayed herbicide to her grass very recently! Is there any hope with these or do I need to pull it out?

Agree with everything gorbelly said. I had plants that looked exactly the same last year... they were mulched with grass clippings from my yard. I didn't apply herbicide but found out later that my neighbors lawncare company sprayed a few patches of clover in my yard abutting theirs to 'keep them from creeping over'. I was ticked off to say the least.

I left the plants in the ground because I didn't have replacements. They never grew out of that extreme leaf curling and I ended up with very little fruit, all of which was deformed, cracked skin, basically inedible. Im up north too and my plants were smaller than your's look based on the pictures - I don't think I even had any flowers on them at the time. So I'm not sure what I would do if I were in your shoes.

Having same issue with 4 of my early girls. I also munched with grass clippings. Neighbors use granular broad leaf prevention. What will the effects be to mulch pile? As I have just recently started adding the grass clippings. I normally use only manure and leaves from the fall drop. I am 30 min. South of Indianapolis, Indiana.

Homepro - I hate to say it but those plants will definitely be stunted. It probably wouldn't be a bad idea to clear all the grass clipping mulch but the damage is probably already done.

If your plants are small and you have access to replacements I would consider it. Sorry.

Its amazing how these tomatoes are so finicky when it comes to herbicides... meanwhile I have some weeds that seem like they could grow in a swimming pool of roundup.

Herbicide carryover has been stalking gardeners for nearly 10 years. Manure, composted or not, also certain grass clippings are the carriers.

See this, including the link at the upper left for a "bioassay" -

http://whatcom.wsu.edu/ag/aminopyralid/images.html