I have a hydroponic garden in a greenhouse in my yard. Everything was going just great until today when I noticed that one of the 7 or so tomato plants (the biggest one in fact) was looking rather wilted. Upon further examination I noticed some brown ooze coming from the inside! I cut off the top branches where I saw this and continued to notice more and more until I finally removed the entire plant (out of concern for the others).
Does anyone know what could cause this? I want to make sure my other plants are not in danger. I've uploaded some pictures to help diagnose.
My first cut into the plant, notice the browning edges:

These yellow and brown leaves were from the bottom so maybe not a big deal?

The inside of the plant close to the base. ugghhh.
