Breeding Sweet Potatoes (early stage)

[Lauren]

I know there's already a post on this topic, but it's mostly people who have been breeding sweet potatoes for a long time and are far along in the process. I'm still trying to get seeds, so I'm starting a new post.

I have two varieties this year--I have no idea what varieties they are as they were both gifts, one white fleshed and one orange. I will be planting both in the greenhouse to try to give them the longest possible growing season in the hope of getting flowers and seeds. The plant (singular) that I had previously died in the first frost and never bloomed.

What conditions do sweet potatoes need in order to bloom (aside from genetics, which I can't precisely control)? Can I help the process along somehow? How long before I can expect to see flowers if they are going to appear?

(FYI, last year's sweet potato test was in pretty much straight sand, under deep mulch, and watered for a few minutes every 10 days. So not ideal conditions, but it had a massive root mass and a few good sized tubers so this year I'm using the sweet potatoes outside the greenhouse for soil building)

[Joseph Lofthouse]

Sweet potatoes seem like one of the most genetically diverse species that I have worked with. In other words, the best answer I can provide is: It depends. I have had sweet potatoes that flower all summer long. Gloriously flowering things, and others that don't flower at all. My primary selection criteria for any breeding project is seediness. The plant has to produce seeds for a breeding project to exist at all. After I can reliably grow seeds, then I'll start selecting for other traits.

[reed]

Lauren, you say you are starting in green house to extend growing time. Where are you located, is your growing season generally considered too short or cool  for sweet potatoes?

[Lauren]

I'm in Utah, and the growing season is too short. I'm hoping if I can get some seeds I can work on shortening the season. Joseph's season is considerably shorter than mine, so there is hope.

I was also working under the impression that the flowers would appear only at the end of the season, which is apparently incorrect.

[Mike Jennings]

I know there's already a post on this topic, but it's mostly people who have been breeding sweet potatoes for a long time and are far along in the process. I'm still trying to get seeds, so I'm starting a new post.

I have two varieties this year--I have no idea what varieties they are as they were both gifts, one white fleshed and one orange. I will be planting both in the greenhouse to try to give them the longest possible growing season in the hope of getting flowers and seeds. The plant (singular) that I had previously died in the first frost and never bloomed.

What conditions do sweet potatoes need in order to bloom (aside from genetics, which I can't precisely control)? Can I help the process along somehow? How long before I can expect to see flowers if they are going to appear?

(FYI, last year's sweet potato test was in pretty much straight sand, under deep mulch, and watered for a few minutes every 10 days. So not ideal conditions, but it had a massive root mass and a few good sized tubers so this year I'm using the sweet potatoes outside the greenhouse for soil building)

Lauren, I could send you a few sweet potato seeds to get you started. PM me if interested. Most of the seeds I produced this year came from seeds that Reed shared with me last year. I've been sharing them with a several new people, but I still have some left I could send out. I'll be planting my seeds for this year's crop any day now!

Depending on how many seeds I can produce this summer (which I hope to be a lot), I was thinking about starting something similar to the Kenosha Potato Project seed trains or maybe starting a new project with the Experimental Farm Network, and really start getting as many people as possible breeding sweet potatoes.

Also, massive thanks to Reed for all the work he's done with sweet potatoes, and being able to share seeds. This is one of the most exciting breeding projects I am currently working on.

[Lauren]

That would be fabulous. I IM'd you.

[Zach E.]

I would love to be part of a collaborative sweet potato prpject, too!

[Kevin Collignon]

Is there any update on this project? I am growing out 11 or 12 varieties this yeah and hoping to get some seed was wondering if Lauren has had any success.

[Garrett Schantz]

Is there any update on this project? I am growing out 11 or 12 varieties this yeah and hoping to get some seed was wondering if Lauren has had any success.

Is there any update on this project? I am growing out 11 or 12 varieties this yeah and hoping to get some seed was wondering if Lauren has had any success.

There is a category on here just for Sweet Potato topics.
http://opensourceplantbreeding.org/forum/index.php?board=11.0

This topic seems pretty old, there seems to be another topic that might work out better for you.
http://opensourceplantbreeding.org/forum/index.php?topic=116.0

There is a discussion for just Europe and just Australia / New Zealand as well. Even if you aren't from those places, they have a lot of information on there.


I am planning on trying out sweet potato breeding next year. I will post a website with a lot of information on sweet potatoes and wild relatives of them.
https://www.cultivariable.com/

For me Lumper - Bloody Banana - Calawah - Chiar Choque Pitu - Solanum hjertingii ​and a few others look quite nice.

If you are new to potato breeding, I would make sure to double check / research on ploidy.

There are all sorts of different ploidy in potatoes: tetraploid -pentaploid - aneuploid - hexaploid etc.

Some things can be easily crossed, others can take a bit of work.

The wilds seem fun to work with - toxic tubers are easy to sort out.

Calawah seems to have an interesting ploidy.

[reed]

It's almost time to start sweet potatoes here, I'll likely be posting some details over on my thread pretty soon.

I'm moving to trialing some of my better plants for actual production instead of focusing on just seeds. Doing that by cloning the best from 2020 in better growing conditions. Also from them I hope to produce a line of elite seed where the chances of any particular seed producing a high quality plant is greatly increased over previous years. I expect the seed from 2021 to be much improved over all previous seed in pretty much all respects but of course I'll have to wait till 2022 to find out.

95% of my seeds are archived for long term storage, still undecided if I will start any seeds at all. I hate the thought of not doing so but about all my pots, tubs and inground space is already reserved for the 2020 clones.

[Kevin Collignon]

I've gone and read most of the posts about breeding on here. I look forward to reading about everyone's progress this year. I am hoping out of 400+ plants mixed between 12 variaties I'll be able to collect some seed and maybe contribute to other peoples breeding projects in some way.

[nathanp]

I received some seed from Michael Jennings in 2020 that I grew out, from the KPP TPS train.  9 / 22 germinated, 8 survived to be transplanted outdoors.  One produced true seed, but only a few that did not germinate this year.  Several flowered profusely throughout the season, but there seemed to be an inverse relationship between flowering and tuber size.  Those that flowered best produced the smallest tubers.  Two of the 8 produced tubers large enough to save for replanting, and I have them in potting soil to develop slips at present.  If these two do not produce true seed this year, I probably will not grow these clones again.

I started 25 seeds with 15 germinating this year.  I did not scarify seeds, but directly planted them in germination mix.  As many as survive into late May or June will be transplanted outdoors.  A few of them look rather weak, so they may not make it.

[reed]

Several flowered profusely throughout the season, but there seemed to be an inverse relationship between flowering and tuber size.  Those that flowered best produced the smallest tubers. 

Yes, that is, was most certainly true in the early years and still is to a degree. Also those that flower most profusely with large clusters of flowers make a higher percentage of seeds that are hard to sprout.

There seems to be a happy medium developing. Many that have just two or three flowers per cluster rather than as many as 15 or more make less seed overall but they seem to be larger seeds that sprout easier. Even though they make comparatively less seeds they make them at nearly every internode. The capsules also more often, contain a full set of four nice seeds. 

Those being cloned this year are mostly of that type. Only drawback is the internodes are farther apart and the plants have larger vines. They aren't giant vines but still not the bushy trait that I am most fond of. I guess you can't have everything.

[nathanp]

For me Lumper - Bloody Banana - Calawah - Chiar Choque Pitu - Solanum hjertingii ​and a few others look quite nice.

If you are new to potato breeding, I would make sure to double check / research on ploidy.

There are all sorts of different ploidy in potatoes: tetraploid -pentaploid - aneuploid - hexaploid etc.

Some things can be easily crossed, others can take a bit of work.

The wilds seem fun to work with - toxic tubers are easy to sort out.

Calawah seems to have an interesting ploidy.

Garret, you may be mixing up regular potatoes (Solanum spp.) with sweet potatoes (Ipomoea spp.)  All of the named varieties you mention are Solanum spp   
For a useful discussion of breeding domesticated Solanum potatoes, see this post.
http://opensourceplantbreeding.org/forum/index.php?topic=14.30

[Garrett Schantz]

Garret, you may be mixing up regular potatoes (Solanum spp.) with sweet potatoes (Ipomoea spp.)  All of the named varieties you mention are Solanum spp   
For a useful discussion of breeding domesticated Solanum potatoes, see this post.
http://opensourceplantbreeding.org/forum/index.php?topic=14.30

I did get them mixed up - typing a bit too late at night I suppose. Thanks for the correction.