Sweet Potato Breeding Project

[reed]

Ended up with 7 seeds before end of July, not bad. Harvested another 1/2 dozen since first of August. Looks like they are ready to really start coming on in next days and weeks. Some plants in particular of most interest and although I didn't expect to do so this early in the project I may want to try and save them for slips next year.  

One, has normal heart shaped green leaves and is growing as a semi-vine. I believe it to be crossed between Hong Kong and Patriot. Branches or what ever you would call them are maybe 1 1/2 feet long making the plant maybe three feet in diameter. Nearly every leaf joint has two to three flowers and nearly every one is developing capsules. It was in the early early germination group and has produced all of the July seeds. ***Capsules on this plant pollinated by I pandurata continue to mature, all other plants aborted those flowers. That doesn't prove anything since they may also have been pollinated by the bees, only next year will tell.

Two, has normal heart shaped purple leaves and is growing as an extreme bush somewhat upright with almost no spreading. It is well less than two feet in total spread. It has huge amounts of flowers in clusters of six or even more. Experience before was that plants with clusters did not set seed good but most on this plant have 2, 3, 4 or even more capsules nearing maturity. I believe this plant to be a cross of the purple ornamental and or one or the other of Patriot or Hong Kong. Won't know till end of season of course but can hardly imagine this plant having much in the way of sizable storage roots however it obviously is a good seed producer and using it's flowers to pollinate others, I am pretty sure it is also a good father plant. I'm thinking it may be valuable in future as sort of a bridge between others. Who knows? 

Three, I love this plant. It has normal heart shaped smallish intensely purple leaves. It has a dense slightly vineing habit, spreading around three feet or a little less total. It was in the early germination group but it has not bloomed yet. It is beautiful and is now starting to develop bloom clusters at all branch tips. Based on time from bloom to seed it probably can't mature any till into September but as long as it makes it before October I'll be OK with it. It is a (S-2) plant, any seeds it makes will be (S-3). 

Four, has normal heart shaped purple leaves and an open semi-vine habit. Clusters of three to five blooms at each leaf joint are developing capsules but not at a high percentage. Many clusters have none and the others have just one or two. I have some hesitation about this plant as I don't like the capsule abort problem but it is making some and it is another (S-2) plant so I'm keeping it around for now.  

Several other interesting plants with wide range of growth habit, leaf color and shapes are blooming now with early stage capsules developing. Some have interesting deeply lobed  leaves. I expect I should get a good amount of seed from all of them before end of August and not to overly optimistic but to continue harvesting at least through September.  Plants form traded seeds and new slip varieties form Sandhill are blooming so new genetics is getting mixed onto later blooms of the early seed producers. 

Hope to have lots of seeds to share with collaborators but will not be offering them in small quantities. 

**Cloned Plant material of any kind is NOT available for sale or trade**, inquiries from strangers will not be answered.  

[notonari]

Exciting, reed. Hope you'll get a good amount of seed. I noticed today that I have the first seed capsules setting, so I'm hopeful I'll have seed this year as well. Given that we've had a summer with temperatures hardly over 20dC so far, and that the seedlings started flowering a lot earlier than last year, I'm pretty happy with how things are developing.

[reed]

notonari, nice to see your update and love checking out your blog posts. I have in the neighborhood of 100 seeds now and hope to have 200 by end of August, almost two weeks earlier than the first ones last year.

[reed]

Just finished an interesting paper on Sweet Potatoes. digitalcommons.lsu.edu/cgi/viewcontent.cgi?article=1594&context=gradschool_disstheses it's a little lengthy and some doesn't apply to me, yet, as I haven't done much so far along the lines of selecting for nice roots.

It does however confirm what I already knew, sweet potatoes ARE sometimes self compatible. They are also as I already suspected sometimes selectively compatible. Maybe self, maybe not, maybe another particular one but not a different one. 

To test, track and document that on even just one is going to be a big undertaking, especially in view of the fact that clones commonly mutate, especially in the first three or four cloned generations. 
 
In other news after reading that I pandurata doesn't make seeds I can say that isn't true. I'v collected  quite a few from the plant up the road which has now quit blooming. Some are from flowers that I pollinated with batatas but I strongly suspect that they and the 9 seeds I got from crossing in the opposite direction are actually not inter-species. I can always hope but the above referenced literature as well as all other info I'v seen indicates it isn't likely.

I'v found several other pandurata plants blooming along roadways but none in spots where it is really safe to pull over.  Most of them are still blooming, I guess cause of different sun exposure. I'm gonna have the woman drive me around so I can jump out to check for seed and tag with ribbons to find later. I think it would be better to have a little diversity in my collected seed if possible. 

[reed]

Hopefully but not likely, next year I can add i batarata or i pandatatas or maybe both  , depending on who the mother was. 

[walt]

Bout time I chimed in here.
Last spring Reed sent me some TSPS.  I haven't mentioned how it is doing.
There were 26 labeled Patriot or Hong Kong, 22 were labeled 1YP.
I soaked the seeds overnight and planted after the weather had warmed up and stablised.
Soil was watered twice daily as it was already getting hot.  The seedlings were up in 3 or 4 days, a big suprise for me.
Patriot or Hong Kong 10 came up.  2 had purple leaves.  Those 2 varied from each other in the amount of purple.  One is much darker than the other.
1YP had 13 out of the 22 seeds.  All have purple leaf veins.  They all have some purple tinting on the leaves.  One is a completely purple plant.  It is much smaller than the rest of  the plants.
Leaves are all heart shape.
No bloom yet.  
I also have a purple sweet potato plant I bought at Kaw Valley nursery.  They have sold it for 3 years now, and I have bought a start each year.  It blooms profusely.  The starter plant I bought in a 2 inch pot already had a flower open.  It is just now starting to bloom again.  So I hope the seedlings start blooming soon.  The plant from Kaw Valley produces a small root that I think is worthless for eating, and likely worthless for breeding.  Pretty though.

[reed]

Great to hear you had success in germination. Does the plant from the nursery have deeply lobed leaves? If so it may be the same as the parent plant of some of the seedlings. I am not sure but believe it to be the ornamental variety known as Blackie. I don't mind using it for breeding as I think it is maybe working as a bridge to mix some of the others and I can now confirm it is self compatible. It's roots are pretty worthless at least when grown in a pot and it's selfed descendants are also worthless.

I am focusing first on seed production and intend to move to root trials next year, well actually I'm very interested in observing some roots this year. Another reason I like the genes from Blackie, if indeed that is what it is, is that it flowers and sets seed in a comparatively short time and I am after short season maturity in all my crops. I am approaching 200 seeds now and plan on saving any that mature after end of August separately. After August seed from the first blooming plants will also be kept separate to try to mix genes from earlier maturity with genetics of the new but later blooming varieties.

I had more plants this year than I expected or had room for so I actually culled a few. Hopefully I didn't screw up because two of the plants I culled whose mothers were Patriot or Hong Kong and whose father was the purple ornamental had extremely sweet and delicious roots, even without curing. They were culled for lack of blooms, one had lobed green leaves with purple veins and one heart shaped green with purple veins. They both had pink skinned roots with orange inside and of surprising size for being culled so early. I considered re-sprouting but figure if those yummy roots showed up in two of the half dozen I culled then whatever genetic combination that caused them should be in some of the others as well.

I have other similar looking plants that are blooming and making lots of seeds so the big question I should have an answer too in a few weeks is, are the traits of lots of seeds and great tasting roots capable of occurring together in the same plant, or am I gonna get one or the other.


Clones of plants by root or cuttings are NOT for sale or trade.   

[walt]

Mu ornamental sweet potato does have very deeply cut leaves.  But I have never seen seeds on it.  I'll look closer this year.
I don't recognize the name Blackie. but we can't go by my memory.  I'll check whether the plant label is in the pot.
All my seedlings have heart-shaped leaves.

[reed]

Here is the plant with the most blooms and seed capsules . Last year plants with clusters of flowers did not produce seed very well bu this one seems to be churning them out. It is an extremely compact and bushy plant which I like. It's mother plant was the purple ornamental and father one of the others. It was fourth to germinate and second to bloom. 


From the ones I have examined there appear to be two types of roots showing up, nice tasty ones and the skinny worthless ones like the original ornamental. Very interested in seeing which this has. If it turns out to have the skinny ones I'm not worried because I  believe it's  children will have at least a 25% chance of having the good ones. I hope to be  expanding the project some more next year and am pretty confident I'll eventually find the two traits of high seed production and nice roots in the same plant. 

walt , have you had any blooming and capsule set on your plants? 

[walt]

No.  No blooms yet.  no buds yet, though it might me hard to see a little bud in among all those leaves.
Checked my ornamental.  No name tag.
I noticed last night that one of the seedlings now has a 3 pointed leaf.  Do some start out with heart-shaped leaves and turn to cut leaves?

[reed]

Yes I have had some do that but they do it very soon, just one or two heart shaped before the lobed ones take over. I have one with sort of toothy edged leaves but it is very puny and hasn't bloomed at all.

[reed]

Hauled in 28 seeds yesterday from that one plant pictured above and about the same collectively from the others. Another plant which bloomed early and made lots of seeds seems to be slowing down. It is more of a vine habit and had only one to three blooms per cluster and nearly every single one made seeds. I think the genetics in these two plants in particular have potential for folks with shorter growing season. Both of course have potential to produce the skinny little roots but also for the nice bigger ones, getting anxious to see which these parent plants have.

Discovered a few days ago there is a little white worm that eats the seeds. They eat holes in all the seeds of a particular capsule. I imagine they have cut my seed collection by 5% so not terribly worried but still something to keep aware of. I had a little bit of bt which I mixed in water and sprayed on the plants and haven't seen any since. I also inspect my collected seeds every day for any signs and at end of collection season I'll freeze the seeds. I suspect they arrived due to poor hygiene when I brought in the I pandurata flowers.

[reed]

I have about around 300 or more seeds that matured before the end of August and started new packs for the rest. I'm keeping a few plants separate. Plants that made the first seeds and that are still blooming, I figure, are now being crossed to the later blooming ones. They are of most interest cause of the new genetics getting mixed with the early maturity. All the others are just going into a mixed pack. No point trying to save late bloomers crossed to early cause the bees are so active and I don't want to mess with bagging and the like. Will see what I end up with at season end, I already have at least 1/2 as many as all last year and sooner that the first ones last year.

Pretty much all seeds so far are from seed grown plants with a pretty good showing of third year seeds.  

A couple early to sprout, early to bloom plants are significantly slowing down on new blooms and some older leaves are fading in color. They have quite a few capsules still maturing. They kinda seem to be acting like an annual, I think I like that but not sure. If they turn out to have nice roots then I'll be sure. 

[reed]

I did a massive pruning of the sweet potato patch last night. Over fifty plants crowded into about a 10 x 10 area was just too much of a mess and too hard to find the seeds. I started just clipping out any branches that lacked blooms, no matter what plant it was attached too. Then I carefully followed branches that had made a lot of seeds but were finished and tagged the plant near it's base and then trimmed them back too.

Some more plants that had not bloomed at all were almost completely cut back. Left a branch or two to keep supporting the roots a little in case they turn out good to eat.

I don't really know for sure when you should harvest roots. Around here I think the old timers rule of thumb was to do so just before or after first frost. A lot of sources such as Sandhill talk about varieties being early, mid or late season and most of my original plants came form their early varieties. Other sources such as the University North Carolina describe varieties with specific dtm. I figure especially if a plant has made a lot of seeds, is slowing down on blooming and older leaves are fading in color, then maybe it is ready.

I wouldn't worry about it except all sources talk about a curing period at fairly high temps and our weather has turned unusually cool, I'm seriously thinking of going ahead and harvesting roots form some of the first ones to seed. If any of them have nice roots I would like to do everything right as far as getting them ready to store till next year.

[philagardener]

I think once the heat is gone the growth of the tubers slows dramatically. It is turning into a really cool Fall here too. Sweets are very cold sensitive so definitely dig by frost. I didn't get any blooms in my garden beds but did find a few ornamental purple leaved plants nearby that have been blooming. Keeping my eye on them to see if there are any seed (I got a few last year and have two plants in my garden that grew from those - waiting to see how they do).

I put the tubers in a box (and put that in a black plastic garbage bag) and leave them in a car that is parked in the sun for a week or so to cure. Toasty and humid in there.