What is this?
I apologize it has taken so long to get a response to your question.
A colleague and I agree that the radishes in the picture do not look healthy. Certainly the black lines are not right for any kind of radish. My colleague doesn't think that it’s a disease, because the distribution of the black veins look pretty even and they are distributed all the way around the circumference of the radish. A fungal disease would be a little more patchy or rotten than the picture shows.
The general rule is: if a food does not look like it should do not consume it. That is our recommendation.
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