The bumps are not a problem. Those are places where roots would form if given the opportunity.

The stunted growth and misformed leaves remind me of herbicide damage.

It looks a lot like the plant has been in contact with weed killer, either through spray drift or in the soil. If it was in the soil I would expect that your other plants would have symptoms. Is it possible it was inadvertently sprayed by an herbicide?

It's possible that it was sprayed by a herbicide, but I think it is highly unlikely. It is planted in a community garden, and I know the other planters working in it. All the folks are pretty sensitive to any sort of chemicals (I got dirty looks for spraying my plants with storebought organic insect repellant, so I doubt any of them would be spraying plant poison around).

The growth isn't really stunted, it was just slightly shorter than the other two plants next to it until it started to wilt.

I guess I should mention, it was the first to flower and fruit. It looked beautiful and healthy the first week after the fruits began, but soon turned out like this.

I've begun spraying around with a baking soda/milk/water mixture, just to prevent any fungus from spreading, but I don't even know if that's my issue.

I appreciate your reply lionheart, and I will check around with the other members of the garden to see if anyone has sprayed recently.

Any other ideas?

Tomato plants are particularly sensitive to herbicide. However, other things like squash and beans may not be affected by the same herbicide that topples a tomato plant.

Is that another tomato plant to the left of the sick tomato plant? [Sorry, my eyes are getting old.] :-)

If that is another tomato plant, then I doubt the problem is in the soil or that the manure has been contaminated by 2-4-D. Things such as horse and cow manure are not necessarily safe. If animals graze on weeds treated with 2-4-d, that herbicide passes right through their digestive systems and into the manure. People unwittingly use the manure and it damages their plants.

Or maybe someone sprayed a little Roundup and it drifted.

Just trying to rule out the most common possibility, because that's what it looks like to me.

One other possibility, one that causes deformed leaves, is Cucumber Mosaic Virus. CMV also affects melon, cucumber, melon, pepper, and various flowers and weeds. It is spread by aphids and it also spreads fairly easily by mechanical contamination (carried by the gardener, for example).

I have never seen CMV in person. You could google cucumber mosaic virus and see if that fits.

Those are in fact tomato plants. I recently spoke to a friend of mine who is a graduate student at our university, and he mentioned that my chile plants just behind these plants would have been affected first if it were any sort of pathogen.

One thing I did not mention earlier is that after this began to set in, the leaves would yellow, but the veins would remain green.

My bio grad student friend said that I am probably just lacking some key nutrients (magnesium in this case). Does that sound plausible to you?

I agree with your grad student friend.

It still looks like herbicide damage to me. See link below.

A nutrient deficiency severe enough to cause such damage would be showing up in other plants as well. If there was something so deficient that it caused such hefty damage, I doubt the plant would have taken off at all.

Herbicides cause leaf chlorosis too.

One other thing you could check is to make sure the soil in that area drains well. If that one plant is sitting in a pool of water, it would be very unhappy and eventually die. Normally this would show as yellowing, then browning and leaf crispiness, then death.

You also might get more action on the main tomato forum.

Here is a link that might be useful: Pics of Herbicide Damage on Various Crops