I have been planting and harvesting sun root for a few years but I’ve never been able to harvest the actual seeds of the plants, regardless of having the flowers atracting insects.

Has anyone been able to harvest the seeds? If so, how and when? My intention is to try to grow from seed and see if some variation occurs.

My sun roots develop the usual yellow brownish tubers but occasionally I find some which are reddish or even deep purple; the pulp remains white or lightly yellow but the flavour profile changes drastically, with the purple ones having a very pronounced hazel nut hint.

  • The_v@lemmy.worldEnglish
    3·
    8 days ago

    Another difficult feature to breed J. artichoke is that it is hexaploid carrying 3 times more chromosomes than sunflower [34]. It has been shown that J. artichoke is probably auto-polyploid carrying 3 different elementary genomes named H, C and P [35], as other polyploid species, H. tuberosus displays any regular meiosis et is partially female fertile. Moreover, J. artichoke displays a strong self-incompatibility system that prevents a plant to produce seeds after self-pollination. Because S-alleles in J. artichoke have not been identified success or failure of crosses between clones cannot be predicted and several crosses have to be done to ensure some will succeed.

    https://www.agrobiology.ru/articles/5-2017kiru.pdf

    Translation:

    Hexaploidy = produces very little seed on a good day.

    Self-sterility = it will not produce seed without a different genetically distinct variety. It is unable to pollinate within the clone.

    Most breeding work has been crossing the 6N sun root with 2N sunflowers. This produces a 4N offspring that does produce tubers.

      • The_v@lemmy.worldEnglish
        3·
        8 days ago

        It’s theoretically achievable but would be extremely expensive and time consuming.

        Hmmm… Here a quick stab at methodology to achieve your aims.

        To start if you have the funds, a full sequence of several lines of J. Artichoke and maybe a few accessions of diplod wild types that can make a viable cross. Then create an extremely high density SNP marker profile of the individuals.

        Next generate 6n x 2n crosses to initiate the breeding project. The resulting 4n progeny could be further reduced to 2n via haploid creation techniques. Irradiated pollen parthenogenesis works in the genus. So there’s a possibility it will work.

        Once you have it in a 2n state it’s time to figure out the self-incompatability mechanism. With the mechanisms defined, a introgression strategy is possible to get the original 6n genome into three 2n lines using the SNP markers.

        From there you can do all of the gene discovery and breeding much easier. You can identify genes of interest and manipulate them by breeding the 2n lines. Seed production should be around 1,000x better than the original.

        You can always recreated a 6n line by doubling a 2n plant with colchicine to 4n. Then crossing the 4n x 2n plant to generated a 3n plant. Doubling the 3n plant with colchine creates 6n again.

        All together it would cost around $3-5 million USD per year and take around 15 years to accomplish if everything went smoothly.

        • qyron@sopuli.xyzOPEnglish
          2·
          8 days ago

          I’ll return to you after I won the lottery. Or robbed a bank.

          Interesting read, informative. Truly unexpected.

        • micgerne@lemmy.dbzer0.comEnglish
          1·
          8 days ago

          The alternative would be to not bother with the plant breeding aspect, just try to create mutations with EMS. It’s been done with other vegetatively propagated species like saffron.

          • The_v@lemmy.worldEnglish
            1·
            7 days ago

            But that wouldn’t answer the OP’s questions about their existing population.

            Also…

            Have you ever worked with EMS? It’s the last resort of the desperate. You burn money and time searching for a needle in a haystack.

            It’s useful for creating variations for narrowly targeted objectives with easy phenotyping. Say a color variation in a flower or a herbicide resistance in grain.

            Ploidy also matters a ton for if the mutations will be able express at all. Saffron for example is a sterile triploid. J. Artichoke is a hexaploid- double the number chromosomal copies.

            Side note: For Saffron the outlook for breeding looks to be very good. They have identified the parent species Crocus cartwrightianus. It’s also in a 2n diploid state. Converting the 2n to a 4n and then crossing to make new 3n cultivars is theoretically possible.