Experiment with frost resistant true potato seed
Aug 1, 2022 7:45:01 GMT -6
heavyhitterokra, rdback, and 1 more like this
Post by macmex on Aug 1, 2022 7:45:01 GMT -6
My last experiment with true potato seed flopped, not because any problem with the seed or stock, but because my goats got into the garden and chose to EAT every last plant. Then, I misplaced the packet of seed. Cultivariable had sent me enough seed to have repeated that planting a couple more times but for the life of me I can't find where I put it.
A few weeks ago I finally decided to order more seed and try for a fall crop. Apparently Cultivariable has had a rush on seeds. Today, when I looked, they had a lot more available varieties than back in July. At the time I couldn't order the wide mix of tetrapoids that I had previously ordered. They were out. Instead, I went with a packet which would be even more experimental. This is a packet of seed from a cross between species of Andean potatoes, one of which is quite frost tolerant.
Link: Mixed True Potato Seeds (TPS), Solanum curtilobum
In case they discontinue this seed and the link should cease to function, I'm going to copy some of the description here:
Solanum curtilobum is a different species than the common potato, Solanum tuberosum. This species is grown at high elevations in the Andes because it has better frost resistance than the common domesticated potato. It is a hybrid of tetraploid Andean potato and another domesticated species, Solanum juzepczukii. Solanum juzepczukii is, in turn, a hybrid between high dormancy diploid (stenotomum) potatoes and the wild potato species Solanum acaule. This species gets its impressive frost resistance from S. acaule, which is one of the most frost resistant wild potatoes.
Solanum curtilobum is a pentaploid species; it has three copies of the domesticated andigena genome and two copies of the S. acaule genome. It is able to set seed, but the amount of seed is much lower than domesticated tetraploids. The progeny are not pentaploid. Instead, they are aneuploids that range between tetraploid and pentaploid. Over several generations of growing from seed, they trend toward tetraploid, so you eventually end up with plants that are 50/50 andigena and S. acaule genetics. The results are less predictable than most mixes and range from tiny plants that produce nothing to giant plants that produce huge numbers of tubers. You will find lots of wild traits like long stolons and bitter tubers, but some plants seem to combine domesticated traits with hybrid vigor and really stand out. If you want to breed a potato with frost resistance, this would be a great place to start.
Like most Andean potatoes, Solanum curtilobum tends to have a short day photoperiod for tuberization, which means that you shouldn’t expect tubers to form before fall. I have this warning with a lot of the Andean potato mixes, but there are fewer exceptions in this case. The majority of the plants will be short day. There will be some that aren’t though. I’d say about 1 in 30 produce a good yield in the summer. On the other hand, S. curtilobum has good dormancy and frost resistance, so growing these plants late into the fall and possibly even overwintering them in the ground shouldn’t be a problem.
The seed parents of this mix are plants that I have selected to keep, so they are either heirloom varieties, varieties that I have released, or varieties that I keep only for breeding. The picture above is an output photo of a full bed of seedlings grown from this mix, so it will give you a pretty good idea of what you can expect. What it doesn’t show are the plants that produce tiny tubers or no tubers or that died early in the season and there are more of those with S. curtilobum than most of the mixes that we offer.
This seed tends to be a bit dirty. The debris is just dried bits of potato berries and totally harmless. Because the seed count in these berries is low, there is a lot more bulk material to separate.
I planted a bit less than half the packet on July 19. As of Friday the 29 I only had one plant up, which was a little disappointing. Still, they did say that germination might be lower on account of the experimental nature of this seed. I appreciate that this seed is available at all.
I had the pot at work, under lights, where I could keep an eye on it. This was especially important because of the extreme heat we were experiencing. I didn't want it to dry out. On the 29th, however, I was going to be home for the weekend, without coming in to work. That one plant was looking like it needed a bit more sunlight and I didn't want to risk leaving it unattended for the weekend, so I brought it home. We had a mostly cloudy, somewhat rainy weekend, coupled with a plague of blister beetles in the garden. If I'd have set the pot on the ground that plant might have been devoured by a beetle. So I placed the pot in the greenhouse and checked frequently. Afternoon highs were mainly in the mid 80s and the greenhouse probably didn't go above 100, which I thought was a bit warm for potato seedlings, but it was definitely the best available option. By this time I figured I had one plant to work with.
Wouldn't you know? Last evening when I looked, I had three more little plants sprouting! Apparently this strain of potato is either very slow to germinate or else it benefits from a bit of heat.
I'm kind of excited about this experiment. For one, we have a really long fall in our area. If this one can survive the first frost or two, it's likely to grow and thrive until after Thanksgiving. Secondly, we'll be getting into short days, which apparently is what this strain needs for tuber production. Who knows? I might stumble into something really useful!
A few weeks ago I finally decided to order more seed and try for a fall crop. Apparently Cultivariable has had a rush on seeds. Today, when I looked, they had a lot more available varieties than back in July. At the time I couldn't order the wide mix of tetrapoids that I had previously ordered. They were out. Instead, I went with a packet which would be even more experimental. This is a packet of seed from a cross between species of Andean potatoes, one of which is quite frost tolerant.
Link: Mixed True Potato Seeds (TPS), Solanum curtilobum
In case they discontinue this seed and the link should cease to function, I'm going to copy some of the description here:
Solanum curtilobum is a different species than the common potato, Solanum tuberosum. This species is grown at high elevations in the Andes because it has better frost resistance than the common domesticated potato. It is a hybrid of tetraploid Andean potato and another domesticated species, Solanum juzepczukii. Solanum juzepczukii is, in turn, a hybrid between high dormancy diploid (stenotomum) potatoes and the wild potato species Solanum acaule. This species gets its impressive frost resistance from S. acaule, which is one of the most frost resistant wild potatoes.
Solanum curtilobum is a pentaploid species; it has three copies of the domesticated andigena genome and two copies of the S. acaule genome. It is able to set seed, but the amount of seed is much lower than domesticated tetraploids. The progeny are not pentaploid. Instead, they are aneuploids that range between tetraploid and pentaploid. Over several generations of growing from seed, they trend toward tetraploid, so you eventually end up with plants that are 50/50 andigena and S. acaule genetics. The results are less predictable than most mixes and range from tiny plants that produce nothing to giant plants that produce huge numbers of tubers. You will find lots of wild traits like long stolons and bitter tubers, but some plants seem to combine domesticated traits with hybrid vigor and really stand out. If you want to breed a potato with frost resistance, this would be a great place to start.
Like most Andean potatoes, Solanum curtilobum tends to have a short day photoperiod for tuberization, which means that you shouldn’t expect tubers to form before fall. I have this warning with a lot of the Andean potato mixes, but there are fewer exceptions in this case. The majority of the plants will be short day. There will be some that aren’t though. I’d say about 1 in 30 produce a good yield in the summer. On the other hand, S. curtilobum has good dormancy and frost resistance, so growing these plants late into the fall and possibly even overwintering them in the ground shouldn’t be a problem.
The seed parents of this mix are plants that I have selected to keep, so they are either heirloom varieties, varieties that I have released, or varieties that I keep only for breeding. The picture above is an output photo of a full bed of seedlings grown from this mix, so it will give you a pretty good idea of what you can expect. What it doesn’t show are the plants that produce tiny tubers or no tubers or that died early in the season and there are more of those with S. curtilobum than most of the mixes that we offer.
This seed tends to be a bit dirty. The debris is just dried bits of potato berries and totally harmless. Because the seed count in these berries is low, there is a lot more bulk material to separate.
I planted a bit less than half the packet on July 19. As of Friday the 29 I only had one plant up, which was a little disappointing. Still, they did say that germination might be lower on account of the experimental nature of this seed. I appreciate that this seed is available at all.
I had the pot at work, under lights, where I could keep an eye on it. This was especially important because of the extreme heat we were experiencing. I didn't want it to dry out. On the 29th, however, I was going to be home for the weekend, without coming in to work. That one plant was looking like it needed a bit more sunlight and I didn't want to risk leaving it unattended for the weekend, so I brought it home. We had a mostly cloudy, somewhat rainy weekend, coupled with a plague of blister beetles in the garden. If I'd have set the pot on the ground that plant might have been devoured by a beetle. So I placed the pot in the greenhouse and checked frequently. Afternoon highs were mainly in the mid 80s and the greenhouse probably didn't go above 100, which I thought was a bit warm for potato seedlings, but it was definitely the best available option. By this time I figured I had one plant to work with.
Wouldn't you know? Last evening when I looked, I had three more little plants sprouting! Apparently this strain of potato is either very slow to germinate or else it benefits from a bit of heat.
I'm kind of excited about this experiment. For one, we have a really long fall in our area. If this one can survive the first frost or two, it's likely to grow and thrive until after Thanksgiving. Secondly, we'll be getting into short days, which apparently is what this strain needs for tuber production. Who knows? I might stumble into something really useful!