Jerusalem artichoke true seeds trials

[raymondo]

I have what I hope are two different clones. One has tubers like those on the left in Joseph's picture above. The other has tubers like those on the right. I have planted them together and I am curious to see whether I get any viable seed from either.

[Joseph Lofthouse]

Oct 21, 2012 3:27:58 GMT -5 raymondo said:

I have what I hope are two different clones. One has tubers like those on the left in Joseph's picture above. The other has tubers like those on the right. I have planted them together and I am curious to see whether I get any viable seed from either.

Last year, I grew the wild plants from seeds and the domesticated plant from tubers. The flowering times overlapped, and I got some seed from the domesticated sunroots where I hand pollinated. This year with both kinds planted from tubers, the domesticated sunroot was slower to sprout in the spring, and slower to flower, so it seems like the flower times did not overlap (much). I collected 5 seeds from the domesticated plant. So I'm intending to plant both year's worth of seed next year.

I wasn't paying attention to the sunroot seeds, so it's very possible that the plant was loaded with seeds and they got eaten by the goldfinches which are voracious predators of sunflower family seeds in my garden. If I want to collect sunroot seeds, I either have to pay close attention or use netting.

[Joseph Lofthouse]

As a follow up: I threshed and winnowed part of my sunroot seed harvest today. Here is what they looked like. These were what was left open to bird predation. I have another harvest which were bagged to keep the birds away. I'll deal with those later. This seed was produced by about 20 plants. I had a commercial variety of sunroot growing in the patch, but flowering times didn't overlap much so they mostly didn't set seed. I collected the flower heads from the commercial strain, but don't expect much from them. A few hybrid seeds might be sufficient.

[raymondo]

I managed to collect some seeds from each of the two different types I grew. I've sown some but it's too early to say whether or not they are viable. I don't know whether they will/can cross with sunflowers but there were sunflowers growing in same patch last season. I don't suppose it matters really.

[Joseph Lofthouse]

As a follow up. I threshed the bagged sunroot seed heads yesterday. For collecting the maximum amount of seed - bagging is definitely the way to go. Yield was much higher (20X) on the bagged seeds heads than on the heads that were left open and collected soon after petal drop.

I collected around 50 seeds that might be a hybrid between the commercial strain and the wild strain.

[nicollas]

Great project Joseph !

raymondo, JA and sunflowers can cross pollinate indeed : Sunroot and Sunflower Crosses. That makes a super interesting breeding project

[raymondo]

Interesting link nicollas. I tried sowing quite a few of the seeds but got zero germination. A project for another time and place.

[awildseedvt]

Years back I found a wild strain of 'choke along the ompompanoosuc river here in VT. (interestingly these are almost identical to the Passumpsic River strain from Extremegardener, though she's much farther north and the two rivers are not connected and she found hers in the 1980's. this raises the question of if our two populations are the same and planted by native peoples a long time ago).
Anyway after doing some research and digging roots at various times, and witnessing no (and I mean zero) seeds being produced, the idea of crossing with sunflowers for perennial seed production crossed my mind.
Nicollas I owe you a BIG thanks! That thread you linked to is exactly what I've been seeking (and daydreaming about) for over 5 years now...
The link you gave is so useful, especially the bit about:

Only a small percentage (about 1%) of the large number of hybrid seedlings raised by us had an annual life cycle, i.e., the plants were without tubers and other perennial organs (stolons or root buds)

Characteristically, a certain percentage of plants grown from hybrid tubers do not form tubers themselves, though they do not differ from tuber-forming plants in any other way. Twenty-three of 470 plants raised from tubers, or 4.8%, were non-tuberous, and 14 plants, or 29%, formed perennial root buds, or small stolons without tuber thickenings in the collar region.

I am so excited to finally get this project underway this year! That info has boosted my confidence.

Now I just need to find another population of 'chokes to create some true seed with, as I've already got sunflowers lined up for this year.
Does anyone know of any notoriously early flowering strains? For some reason I remember a beaver-valley or something with red skins, but my memory is fuzzy. Back to google...

[nicollas]

You're welcome awildseedvt.

From Crop Ferality and Volunteerism,

That show the self-incompatibility of H. tuberosus, and a 12-15% cross pollination by insects.

And from Diversity of Jerusalem artichoke clones (Helianthus tuberosus L.) from the INRA-Montpellier collection

Seed sets on Jerusalem artichoke plants were deter-
mined before 2005. Ten heads were left in open
pollination, the pollen cloud being determined by the
whole collection in isolation in the experimental field.
Of the 166 clones or wild populations observed, 142

clones blossomed and displayed normal heads. No
other Helianthus were grown around the plot.
Among the 166, 96 (67.6%) produced seeds in
free-pollination. A set of 24 clones did not produce
any seeds. The 26 wild natural Jerusalem artichoke
populations produced more seeds (20.9 seeds per
head) than cultivars (6.2 seeds/head). The distribution
of female fertility measured on 142 Jerusalem
artichoke accessions is shown in Fig. 4.


This data shows that under a favourable pollen
environment many Jerusalem artichoke clones can
provide enough seeds to open the doors for a genetic
improvement (missal selection as example) of Jeru-
salem artichoke by crossing clones with complemen-
tary traits.

Anyone know where i can get true seeds of JA ? The source given by Joseph seems to not send seeds oversea.

[Joseph Lofthouse]

Mar 3, 2014 8:33:03 GMT -5 awildseedvt said:

Anyway after doing some research and digging roots at various times, and witnessing no (and I mean zero) seeds being produced

I pretty much have to bag flower heads if I want to collect seeds. Goldfinches are an extremely effective predator of sunroot seeds. In my garden bagged seed heads yield 20 to 40 times more seed than non-bagged seed heads.

[awildseedvt]

Nice, Nicolas, confirmation is a good thing, thanks!

Yes I saw you mentioned that Joseph. Here the issue is self incompatibility. Though originally I believed it was because of the september rains (cold/wet/frosts) ruining developing seed heads as happens with amaranth, teosinte, late corns, sorghums, and other autumn harvested flower/seed crops. Other than daylight sensitivity the absolutely ruddy weather in autumn is my biggest challenge for acclimating crops that aren't usually grown here. Since then we've had a few "perfect" autumns and still no seeds to be found (not even at the premature stages), so I'm almost certain they just need another choke to pollen swap with.

[Joseph Lofthouse]

With a self-incompatibility rate of 99.2% I'd expect about 1 seed per 3 flower heads. If there are around 200 flower heads per plant I'd expect a single self-incompatible plant to produce about 70 seeds. Sure it'd be a pain to thresh a gallon of seed heads for a quarter teaspoon of seeds. It's not like my labor has a price attached. To me, those are fantastic odds for a plant breeding project. Goldfinches could make the odds very unfavorable if measures weren't taken to protect the seeds.

Once I started paying attention, wild sunroots are very common. Around here they typically grow in the meadows adjacent to waterways. Last year's stalks are still standing. I keep thinking I aughta go collect a couple of wild locally-adapted tubers to add to my collection.

[trixtrax]

Yes Joseph you aughta! Sounds like a great project. Germinating soon a bit of seed of sunchoke from billw. Can't wait until the end of the season to see what comes up out of the soil.

[kevin8715]

I have 8 seedlings. Plan to plant 7 in back in an isolated bed and keep one in a pot for security.

[awildseedvt]

I dunno joe, I pulled apart dozens and dozens of heads at the different stages of the flowers life/maturity and never saw a single premature or mature seed...and I tried multiple years. We don't have many wild chokes here, we're not in the choke's home territory here and as I mentioned both documented Vermont strains from different counties may in fact be the same plant. It sounds like you've got alot of wild pollen floating and buzzing around there to help your odds. How is the weather in autumn? We consistently get cold WET moldy septembers and octobers, it puts a major damper on late ripening seed.
BTW I like your approach and work with the chokes, very nice ideas and documentation, can't wait to see more this year.

great to hear kevin - I hope to see alot of people's 'choke grows this year. you too trixtrax, glad to see more working with these.