Yellowing leaves on previously healthy plants

[Mike_d_s]

Hi all,

I've been raising tomatoes for a few years now without too much issue, this year I have a problem that has sprung up in about the last week. I'm not sure exactly when I started as I was out of town and just noticed it when I got back this week.

Basically I had what were healthy plants and two of them have started getting yellow leaves and one particularly is looking very bad now.

Initially a few days ago, just the leaves were yellow with both older and newer growth yellowing. The leaves themselves initially didn't look unusual other than turning yellow, not really curling or spotted. But in the last few days, the stems are yellowing as well and the yellow leaves are really wilting. I also noted the one tomato with the worst yellowing has a bunch of nodules along the stem which I always heard was a stress response so I guess I shouldn't be surprised.

Also I noticed as well the cherry tomato next to it is starting to show some yellow leaves as well on the side facing the bad one, so now I'm starting to worry as it looks contagious.

This is the first time I've had this kind of problem in my patch and while I'll hate to pull the plants, I don't want to lose any more if I can help it if there is no hope.

What do you think, am I out of luck here with these plants?

thanks,
Mike