If it's Fusarium, it has contaminated the potting mix and the pot.

But one wonders why you might have Fusairum in a container. Did you add ground soil to it?

If not, perhaps the tomato is rotting simply due to excess moisture? Stick a finger in the mix -- how wet/moist/dry is it?

No additions made to potting mix. I had similar problem in a couple of Earthboxes last year. All plants last year came from a nursery so they must have been contaminated when I got them. I didn't keep note of which boxes were affected. I'll do better this year. This years plants were all started from seed, so it is either seed borne or from last years plants. Other boxes are doing fine so don't think it is a watering problem.
Thanks for the feedback.

Well, whether or not you think it isn't a water problem, stick your finger in the potting mix to find out for certain.

Removed both plants today. On one, roots brown, brown lesion at the soil line, greenish yellow "pustules" on stem, brown streaks in vascular layer on lower stem and decaying pith. Other plants roots were beginning to brown.
Moisture seemed to be just right in potting mix. It's hard to over water in an Earthbox unless you let to overflow hole get stopped up.
Sterilized container with clorox solution. Will refill with new mix tomorrow and plant rooted cuttings.
Thanks

Whizzer, what are the specific symtoms ( please describe in detail any wilting if so what color was the foliage, and lesions on the leaves, etc, that you saw to allow you to match it up with Fusarium Crown Rot, which would be a very very far out Dx for your situation.

And how big are the plants?

Carolyn

Carolyn, Thanks for responding. As you have said before the photos in Tomato Problem Solver and elsewhere are static and don't show progression. This makes it hard for a neophyte like me to diagnose.
Plants were about 5+ feet tall. Leaves began to brown at the edges, becoming crispy, then yellowing and spreading to the entire stem until it withered completely. I didn't notice any lesions or spots on the leaves until they were completely dead, then some dark spots in the brown. When I noticed a large brown area on the stem near the soil line on one plant I scratched down to the roots and discovered them to be brown. Cutting into a lower branch I could see light brown under the green outer layer. Can't refresh my memory because the "sanitary engineers" carted off the remains yesterday. When I removed the plants, the one with brown lesion on stem was mostly hollow (pith gone) for several inches above ground and had greenish yellow bumps on the outside above the brown area.
I have the brown edged leaves on other plants, but they progress to complete brown and don't turn yellow. This must be some foliage disease that I can't identify (Carolyn's CRUD ?).
I had similar problem on some plants last year that came from a nursery that may have been diseased when I got them. This year I started seed and think my soil may have been contaminated by last years plants. I spray with Daconil every 7 to 10 days.
Thanks for your input.

Wow. Either I've been totally off on my diagnoses, or that's the third case of what I suspect to be tomato pith necrosis I've seen on this forum this season. It's not supposed to be that common.

Brown rot causing hollow stems, some discoloration under the skin at the soil line, "laddered" pith, and adventitious roots (the bumps you found) above the rotted portion are all characteristic of tomato pith necrosis. It is soilborne, which makes for an interesting problem. Where did it come from?

Soil contamination from last year could do it; not sterilizing the pots could do it too. One other thing to check -- does the mix you're using have any soil in it at all? "Premium topsoil" or some such? Actual soil, rather than the soilless mix most often used in pots, could have provided contamination.

At least container gardening makes it possible to start over, for next year if nothing else. Just make sure you've scrubbed everything down with disinfectant and gotten rid of every scrap of soil.

--Alison

All my boxes have either Miracle Grow potting mix or Jungle Growth potting mix, neither of which indicate they contain earth. Other plants, while showing some foliage disease, do not have the same symptoms as those in question. In a week of so I'll see people I shared plants with and find out if they have same problem. That should tell me if is soil borne or seed borne.
Thanks for your input Alison

Update. Contacted two people I shared plants with. Neither have had problems with the variety I have so I'll assume it is not seed bourne and sterilize pots and change potting mix accordingly.