Greetings. A year late to the party, but topic appears to be relatively fresh with a new post. Funny you should ask about subsistence potatoes. I’m working on just that.
What would be some defining attributes?
High productivity, high disease-resistance (“subsistence” implies you don’t have a lot of budget for chemical inputs), long-keeping, seed fertile.
What fits our climate patterns?
High resistance to fungal diseases.
Personally, I’ve grown indeterminate potatoes for so long I’m used to them, tho people in other parts of the country often express dismay when they run into one. Not sure how others feel about them, or how they might impact cultural practices. I’m not a farmer.
Irrigated or dry farmed?
Irrigation probably superfluous in maritime climate regions. Inland northwest is another matter.
Would low dormancy potatoes have a place as a reliable staple?
Perhaps, but only if you’re committed to raising them from seed. Otherwise, you’ll be vulnerable to losing the tubers as they accumulate disease and eventually rot in storage.
Would there always be a spot for seedling (TPS) potatoes each year to keep genetics and disease resistance changing?
Personally, I’m wary of crops that have been vegetatively propagated too long. Even if I didn’t run into problems that forced my hand, I would regularly, proactively renew from seed to avoid problems up-front.