Something wrong with potato plants?

Question

Hello,
A few weeks ago my potato plants were stripped of their leaves by my chickens. The leaves all grew back in a few weeks, but on some of the stems they have gone purple and lumpy looking, and in some areas there are new roots starting to grow from out of the tips of the stems where the lumps are? (The variety potato I am growing is Dutch Cream)
Any insight to what is going on would be very much appreciated.

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Answer 1

It seems to match up with the symptoms of early blight. https://www.canr.msu.edu/resources/potato_diseases_early_blight_e2991

The spores find entry into the plant in spots where it's been damaged.

Although these don't refer to damage of the stems, here are a couple of our articles that may help:
https://www.gardeningknowhow.com/edible/vegetables/potato/potato-early-blight-treatment.htm
https://www.gardeningknowhow.com/edible/vegetables/potato/potato-blight-diseases.htm