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  • Possible way to produce FMV free plant....?

    I was doing a little research on FMV and stumbled upon the University California Integrated Pest Management website which stated that FMV is not seed born. This meaning that an infected plant doesn't pass the virus onto the seeds. I've read that figs can reproduce by means of Apomixis where there is no need for a plant to be pollinated to produce viable seeds. This meaning that a common fig can produce viable seeds without pollination. These seeds are supposed to be exact clones of the mother plant( making them all Female-edible fruit producing) I've read that some people have actually grown seeds from fruit in areas without the wasp. My question is......why doesnt somebody with a Black Madeira or a Black Ischia or any other variety (usually heavily infected with FMV) that lives in an area without the fig wasp try to grow some seeds from one of their fruits. Being exact clones, you wont run the risk of having any male caprifigs and it will be FMV free. This experiment will take about 2 years or so to try.......or however long it takes to grow a plant from seed to fruit.... worth a shot? What do you guys think?.......Just something to think about....
    Quy
    SoCal, Zone 9b

  • #2
    Tissue Culture is another way to achieve FMV free fig trees.
    Meristem Thermotherapy during the tissue culture process. Agristart will produce tissue cultured plants for retailers, http://www.agristarts.com/index.cfm/...D/22/index.htm . They have a minimum order and only sell wholesale.
    Pete R - Hudson Valley, NY - zone 5b

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    • figherder
      figherder commented
      Editing a comment
      They have a list of figs that they do. Black madeira isnt on it. .

  • #3
    Apomixis is not very well understood in figs. What I have read suggests only a few varieties are able to produce apomictic seed, and some need to be induced by using related species pollen (mulberry, osage orange). Also, the seedlings will not necessarily be clones, one pathway to apomixis involves meiosis, where the genes are split apart and recombined during meiosis (if anybody else understands this please chime in because the details are over my head).

    The seeds will be FMV free, all seeds are, and they should all be female like you said (female figs are homozygous recessive ga/ga). Some may not end up being persistent though, that gene is heterozygous dominanat (P/p) so recombination might result in some p/p (caducous). There are a couple papers observing the variation among generations of seedlings but they are not free

    I have been looking for apomictic seeds in figs that have spoiled or took bird strikes, tried mulberry pollen one year but it was a disaster. Some people do find apomictic seeds, FMD (Frank) grew a Celeste from an unpollinated seed. I will keep trying, no harm in that.
    .

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    • #4
      HI Brent,
      I was throwing out a hypothesis on how to do possibly come up with a FMV free plant. I had no clue how in depth apomixis was. I think its awesome that you've tried to grow non-pollinated seeds and that you've done soooo much research!
      The diagram that you put up is of sexual meiosis, where one mother cell divides to create 4 haploid(half genes) daughter cells...(egg cell or sperm cell or in plants pollen) The diagram of meiosis is a little confusing because the start of it already shows duplication and it shows crossing over. I'm going to try to simplify it in terms of your diagram. All a cell needs is to consists of (AB, ab)....thats what the normal/complete parent cell looks like....the beginning of the diagram shows them already duplicated with 4 sets not 2. So in the second division it creates 4 sex cells with half the DNA....so when combined sexually with another set will produce a zygote(baby cell with all DNA needed) To my understanding the other forms of apomixis do not involve meiosis because they are a mutated form that by passes meiosis where the splitting of the cells DNA doesn't occur....therefore keeping (AB, ab). If indeed a form of meiosis occurs ...then the recombination must be made from the foreign pollen(from mulberry etc...) thats where the genetic material will differ and it not be a clone. I'm sure there are many different ways for a viable plant to be formed (plants are crazy...some dont even need all the genes to actually grow....some have many mutations...)...the hard part is getting a plant that is viable and produces fruit. This is probably where all the different variations of apomictic figs come from.....that and the recombination of non fig genetic material....plant genetics...hahaha crazy stuff!
      Quy
      SoCal, Zone 9b

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      • #5
        The diagram, along with the descriptions below come from waynesworld. The first a lab and the second specific to figs.
        Some plants and animals reproduce asexually by a process known as apomixis. Their offspring develop from unfertilized eggs which are often clones of each other. Apomixis is more common among plants and certain insects than other animals. In general there are two main types of apomixis: [1] Parthenogenesis (agamogenesis): A haploid or diploid egg cell develops into an embryo. Contrary to some authors, parthenogenesis does not always result in genetically identical clones. If the haploid cells are formed by normal meiosis (as in the queen honeybee), crossing over during Prophase I of meiosis may result in some genetic variability. Crossing over is discussed later on this page. If the unfertilized eggs develop from mitotic oƶgenesis (without the reduction division of normal meiosis), then their offspring will be identical clones of each other.
        [2] Agamospermy in plants: An embryo arises from tissue surrounding the embryo sac. If this involves cells of the nucellus or inner integument it is called a nucellar embryo. Nucellar embryos are chromosomally identical to the sporophyte parent. They are essentially clones of the female tree. Apomictic seeds allow propagation of choice edible fig cultivars (female trees) without the transmission of viruses through cuttings.
        Female cultivars may also produce apomictic seeds--i.e. without pollination and subsequent fertilization (need reference here). In general there are two main types of apomixis:
        [1] Parthenogenesis (agamogenesis): A haploid or diploid egg within the embryo sac (or diploid cell from 2 fused haploid cells of embryo sac) develops into an embryo. [Formation of haploid cells may involve crossing over during Prophase I of meiosis resulting in some genetic variability.]
        [2] Agamospermy: An embryo arises from tissue surrounding the embryo sac. If this involves cells of the nucellus or inner integument it is called a nucellar embryo. Nucellar embryos are chromosomally identical to the sporophyte parent. They are essentially clones of the female tree. Apomictic seeds allow propagation of choice edible fig cultivars (female trees) without the transmission of viruses through cuttings (need reference here).
        Using pollen from other species, and observsing variability of seedlings was done in India about 50 years ago. So maybe mulberry genes are incorporated somehow, only the abstracts are available. The more current theoretical info above does not mention any foreign pollen, so only the mother's genes are involved, the only way they could change is if a segment became homozygous. The mother is AB and one segment ends up being AA or BB...
        .

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        • #6
          It makes sense. If there was cross over then a mutation where they didnt separate and become haploid....you'd have offspring that is not a clone of the mother plant. I wonder if slightly different versions of figs (Mt. Etna type figs) are because of apomixis or mutations or if they are hybrids. I know there is little DNA testing done for figs but i know somewhere that some varieties test the same for DNA but have different characteristics in fruit. Maybe there are different factors in the control of gene expression. So much that is unknown.....makes it interesting though doesn't it?
          Quy
          SoCal, Zone 9b

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        • #7
          Has anyone made any progress with testing seed-grown figs using seeds that are the result of apomixis rather than caprification?

          I was bored the other night and had a couple of sacrificial figs that I extracted seeds from - 2 Black Genoa and 2 St Dominique Violette. There's no fig wasp where we are apart from native ones which pollinate the Moreton Bay figs, so my test figs were not caprified - and I wasn't expecting to find any viable seeds.

          As I soaked and cleaned the flesh, I discovered viable seeds sinking to the bottom of the dish. The viable seeds are a light brown colour, while the others are more of a cream colour.

          The discovery of viable seeds led me down the google rabbit hole for a day researching how this could be so, which lead me to apomixis and right back here once I had a name to define how these viable seeds came to be.

          To sum up what I found on my latest research journey into the world of figs which confirms previous discussion in this thread and adds some additional info re breba figs:-

          1. The process of apomixis can result in fertile seeds without pollination and the normal process of sexual reproduction.

          2. Figs from the breba crop are the most likely to produce fertile seeds via apomixis,

          3. Plants grown from apomictic seed will be clones of the mother plant/tree.

          4. Apomictic seeds do not transmit viruses.

          One thing that puzzles me is that apomictic seeds are said to be rare, but I extracted maybe 100 viable seeds from the Black Genoas and around 60 from the St Dominique Violette figs.
          Kate - on acreage in a subtropical/warm temperate growing region in south-east Queensland, Australia

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          • #8
            Hey Kate nice work. My thought is maybe the seeds sink but won't actually grow. Are they really viable?
            Alpine, Texas 4500ft elevation Zone 7
            http://growingfruit.org/

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            • #9
              fruitnut - all of the stuff I've read on fig seeds says that viable seeds sink once you extract them from the flesh, and all the floaties should be discarded as they aren't viable. It was interesting to note the distinct colour difference between the two. As to whether I can get them to sprout - that's another matter entirely which could be due to poor technique on my part or seeds pretending to be viable It take about 6-8 weeks for fig seeds to sprout which is comparable to getting coffee seeds to sprout, so I'll be interested to see how long it takes for these seeds.

              I did see a good video on growing fig seeds, and that person used peat moss with a little bit of perlite. The seeds were spread over the top and then perlite was sprinkled over the top of the seeds. A takeaway food container with lid was used, so I might use a similar process with some large strawberry punnet containers.

              The recent video of the lady who grew those fig trees which produced fruit within a year sort of inspired me to take another look at seed-grown figs. There's clearly potential for a quick turn-around from seed to fruit to test the hypothesis that apomictic seeds produce disease-free clones of the mother tree. I havn't found any actual research on the topic of figs yet - or any outcomes from people who've grown these types of fig seeds. There's certainly research into other food crops and plants - just not anything that was easy to find on figs.

              I figured it was worth revisiting this thread given it's almost 2 years since it was started, as I was hopeful someone may have been busy growing seedlings.
              Kate - on acreage in a subtropical/warm temperate growing region in south-east Queensland, Australia

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              • #10
                At what point in fruit development does apomixis occur? Seems like a good experiment for figs that aren't going to ripen in time (even if breba are most likely to produce viable seeds).

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                • NangkitaKate
                  NangkitaKate commented
                  Editing a comment
                  I don't have an answer to that question mosier - sorry. I've only just started to delve into apomixis, and it'll take a while for me to get it all straight in my head

              • #11
                FASCINATING! Well I am aware some would want the seedling to be an exact copy,but crossing over will not necessarily alter ALL the phenotypic characteriistics(the seedling will not necessarily be TOTALLY different from it's seed parent) but may have some differences that are observable,or some that are not.So A BM apomictic seedling may have fruit exactly or almost identcial to the parent, but a different leaf pattern for example(or lousy fruit and same leaf!) thus one would require planting out numerous seedlings and evaluating them.It is not necessary to get an exact identical copy of BM.An apomictic seedling of BM that has bigger fruit, more cold tolerance, more vigorous growth/dwarf growth,different color fruit,even better flavor,fig rust or RKN resistance etc. COULD be discovered and would be useful with FMV absence to boot!Such a fig would be perhaps more sought after than the original BM parent if it were superior..And should be at least more like the seed parent than a seedling from a pollinated fig .This experiment is within easy reach or every forum member and would cost nothing but a small amount of time.Lets roll! Kate, you are the example for all to follow.
                Z8A NC SANDHILLS

                WISH LIST BURGAN UNK, ZAFFIRO,

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                • NangkitaKate
                  NangkitaKate commented
                  Editing a comment
                  Thanks YATAMA I think it's worth trying, even if you just end up with a bunch of root stock to practice grafting on. When my Blue Provence and Excel produce fruit next year hopefully, I'll test grow their seeds too - as they look to be affected by FMV to varying degrees.

                  Fortunately you don't have to sacrifice a whole fig to get the seeds You just pluck the top layer of flesh out of the cavity with tweezers, as that's where the seeds are. Then you can eat the rest of the fig.

              • #12
                Well Kate,you HAVE YOUR FIG AND EAT IT TOO! To further elaborate on seedlings that are copies of the seed parent,its well known citrus seed like oranges are nucellar and produce an exact copy of the seed parent,often one seed produces multiple seedlings most identical but if flower was pollinated and it always is, there can be one additional seedling from that same seed that is result of cross pollination and thus genetically different from the seed parent. clearly individual fig seeds only produce a single seedling,however it's also possible that figs pollinated by wasps may have two kinds of seeds.The one resulting from pollination and other kind that may be the apomixis seed ,as the wasp may not hit every where inside fig with the polllen?Interesting consideration to ponder.
                Z8A NC SANDHILLS

                WISH LIST BURGAN UNK, ZAFFIRO,

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                • #13
                  I found a nice article which simplifies the explanation of apomixis:- https://biology.tutorvista.com/plant.../apomixis.html

                  Also found a couple of research papers on understanding apomixis, and its importance in plant breeding:-

                  http://www.plantcell.org/content/16/suppl_1/S228
                  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4063905/

                  Those two are a little heavier reading - and are making me nod off
                  Kate - on acreage in a subtropical/warm temperate growing region in south-east Queensland, Australia

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                  • #14
                    Foundfollowing statement on waynes world article on fig pollination,seems others have consdered the topic that the author who started this thread brought to our attention.Sadly no reference to how wayne `got this concept theoretical vs actual:

                    [2] Agamospermy: An embryo arises from tissue surrounding the embryo sac. If this involves cells of the nucellus or inner integument it is called a nucellar embryo. Nucellar embryos are chromosomally identical to the sporophyte parent. They are essentially clones of the female tree. Apomictic seeds allow propagation of choice edible fig cultivars (female trees) without the transmission of viruses through cuttings (need reference here).



                    Z8A NC SANDHILLS

                    WISH LIST BURGAN UNK, ZAFFIRO,

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                    • #15
                      YATAMA - yes - found a similar statement in an article here:- http://www2.palomar.edu/users/warmstrong/pljune99.htm

                      There's a lot of theorizing for and against, but no research or simple blog posts by anyone who has grown a fig tree to fruiting stage using apomictic seeds. I'll have to keep dredging Google.
                      Kate - on acreage in a subtropical/warm temperate growing region in south-east Queensland, Australia

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                      • #16
                        Well I saw that.Actually what is the best solution to the question is of course for the our figs research team(that means all of us!) to answer the question ourselves.We have the extensive numbers of fig growers than far surpasses the tiny number of professional university researchers who of course are not devoting ANY time or resources to the question.All of us are experienced in rooting figs with at least some degrees of success .To attempt to grow fig seedlings from unpollinated fig seeds(figs from areas with no wasps) would require little additional effort to our already vigorous cutting propagation work.If everyone here took a common fig of interest and tried to sprout it's seeds and kept records, we could have a thousand or more experiments running at a thousand different places this very season with maybe a thousand seeds being sown by each member thats a thousand squared experiments which is one million seeds being evaluated.If we get no seedlings with that effort the issue is probably closed If we get even one seedling in the million seeds planted, we have a soild discovery.I will be running the experiment here and ask everyone in this forum to discuss this widely to achieve maximal participation this year.If we do not do that we should turn in out fig licenses,and eat canned pears for the rest of our lives!
                        Z8A NC SANDHILLS

                        WISH LIST BURGAN UNK, ZAFFIRO,

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