Is that all on one plant? Or several?

It helps to put a sequence of images for each plant 1. plant & its surroundings; 2. the plant alone; 3. a close up of damage including the junction with healthy part.

Some of the damage looks like a broken stem; and/or old leaves; and/or minor damage that can be ignored.

Further, because you are growing in a protected site, are you in pots and potting soil;hydroponics; or what?

then, what are you doing for fert; water; hours of light; etc?

What treatments have you tried and what was the result?

Thanks Jean, I will work on this. Peggy

Ok. Here are some more photos. I grow in a greenhouse, in the ground. The soil is a mix of native clay soil with a very generous amount of compost mixed in. I fertilize generously with compost, sulfur, alfalfa pellets, dried chicken feathers, and dried seaweed. My tomatoes have this problem every year. The plants are still productive, but I just always wonder what it is.

Here is the entire greenhouse:

Plant 3:

And here are a few more Plant 3 photos: