The inheritance of recessive and dominant mutations in daffodil cultivars

This is the title of an article from Peter Brandham in the “Daffodil, Snowdrop and Tulip Yearbook 2017, pages 26-32”. Essential statements in this paper are:

  1. Pitfalls often occur, one of the more disappointing being the mysterious disappearance of some exiting new form, colour, decease resistance, etc. from all the progeny of the plant in which it was first seen.  … In daffodils, this disappearence seems to happen when plants with pink or red coronas (e.g. ‘Brer Fox in division 1 or Mrs. R.O. Backhouse, division 2) are crossed with other colour forms … Disappearing characteristics are due to the inheritance patterns of recessive gene mutations, ..
  2. Their are some diploid and intermediate triploid cultivars, the latter’s three chromosome sets rendering them almost completely sterile due to failure of the meiosis…
  3. This is because the genus is known to be almost completely self-incompatible, with the stigma of a flower rejecting the pollen formed by that or any other flower of the same clonal variety…

These declarations should be thoroughly discussed, because they may mislead new or unexperienced hybridizers. I hope that other breeders report on their know-how, especially concerning self-incompatability. Some of my thoughts you find in the PDF-paper The inheritance of the red and pink colour, the fertility of triploids, and the self incompatibility of daffodils remarks to (1)

Theo

11 comments for “The inheritance of recessive and dominant mutations in daffodil cultivars

  1. Many thanks Theo for this excellent clarification. Maybe this shows the difference between a pure scientist and a horticultural one?

  2. Anne & Theo,

    What a useful article on this subject Theo. I will print it off for future reference.

    The idea of creating Tetraploids from triploids by selfing is new to me and I wish I had known many years ago. I hope it is not too late !!:-)

    Well done Theo.

    Brian

  3. Hi Theo

    I posted this reply days ago with photos but it seems to have disappeared into cyber-limbo.

    Thanks for your observations.

    I think you are right on all 3 points. Namely:

    1/ The colours white and yellow are not dominant over red and pink.

    2/ Many triploid plants have useful fertility.

    3/ The theoretical view that daffodils are “almost completely self-incompatible” distracts from the common and sometimes important ability of many daffodils to self.

    As regards point 1, it is worth noting that the wild hybrid N. x boutignyanus, between a white trumpet and a poet, can have orange in the corona (see RHS Daffodils 1993-4 Fig 9). Nevertheless poet alpestris hybrids do tend to be white or white-yellow and strong orange only re-appears in the next generation.

    Horace x alpestris seedlings have given 08_31D ~2W-O, 13_96D 2W-W, 13_72D 2W-Y

    13_61D is (poet x alprestis) open pollinated and is quite poet like, a drooping 2W_YYO.

    Color in daffodils is complicated and cannot be understood by supposing one color is determined by one gene.

    Characteristics that depend on a combination of genes can disappear and then reappear in subsequent generations in the way that a characteristic determined by a single recessive gene does. Hence the same advice applies – keep good records and back-cross.

    Historically it has been more difficult to produce orange trumpets than pink ones; harder to produce yellow pinks than white pinks; harder to produce pink and reverse bicolors in division 3;. There seems to be a special relationship between pinks and reverse bicolors.

    Perhaps my most unexpected result has been from Alimony 3W-W x Impeccable 2Y-Y. 06_51 is 2Y-Y almost 2W-Y, which makes sense, but 08_55 has orange pink coloring.

    As regards point 3, I try to avoid selfing daffodils and have the strong impression that open pollinated seeds from standards here are mostly from selfing and they result in seedlings with much reduced vigor.

    As regards point 2, the fact that fertile daffodils can arise from selfing (Silver Bells -> Mission Bells) suggests that it is easier to obtain fertile tetraploids by crossing triploids, not with themselves or other triploids, but with the kind of tetraploids one is trying to obtain: – perhaps Mission Bells x Akepa; Matador x Cheerfulness; Limequilla x Intrigue etc.

    Larry Force speculates on tetraploid div. 6 parents here:
    http://daffnet.org/more-on-division-six-fertility/

    Crossing these with div. 6 triploids is probably a good idea.

  4. Lawrence,

    Even when they were not directed to me, thanks for the comments. It seems to confirm many things that I have seen in my hybridizing.

    clay

  5. I am glad about so much agreement and valuable additions to my thoughts.

    Arrowhead is a cross of (Jetfire x Trogon) x N. cyclamineus correspondent to DaffSeek and therefore should be triploid. But the pollen fertility is about 80 %. This is too high for a triploid. I think in reality it is tetraploid: (Jetfire x Trogon) combined with a tetraploid, probably (Jetfire x Trogon) selfed.

    Theo

  6. Okay Lawrence and Theo how about this, based on the information given above.
    This morning I have planted fat seeds of a cross I did last September. The cross is (Air Castle x Emerald Pink) 3Y-W x (Sabine Hay x Altruist) 3O-O.
    My aim is for 3O-P, 3O-W or 3O-Y. What are the most likely outcomes of the cross? or is it a matter of Y-P upwind? or do I have to wait for another generation to flower in ten years time by which daffodils may well be decorating my plot?
    Your thoughts will be interesting.
    Dave

  7. Hi Dave

    The most likely outcome is 2W-O. That’s my initial thought. I have done many of these kinds of crosses but would need to do a lot of checking to give a good, well justified, answer. I think it highly unlikely your aim will be realised, but you never know.

    There is a fairly distinct beige color in reverse bicolor daffodils and so 2BBW-W is easily possible but it is hard to turn the beige into orange. Orange in the perianth is itself interesting. The feeling I get is that perianths are either white or yellow with some orange in them – they don’t give the impression of being orange in their own right in the way coronas do. I think there is a second distinct line of breeding toward orange perianths that involves breeding darker yellows. It occurs to me that there is an association between this kind of breeding and reverse bicolors, Abona x Chiloquin comes to mind, but that too would need checking.

    17_55 is about as 2O-W of anything I have. Apologies for the poor photo.

    I forgot to mention my surprise reading that paperwhites and tazettas are self sterile. I have the impression that N. pachybolbus and my diploid Soleil D’Or readily self. Taztep, a tetraploid hybrid between the two groups, is perfectly self-fertile such that it must be deanthered prior to opening when it is used as a seed parent.

  8. Lawrence,
    Thank you for your prompt response. Another factor comes into this. Many so called orange perianths are only orange flushed, that is orange over yellow. The perianth on my seedling is pure orange as in Sabine Hay and Altruist.

  9. Dave,

    I agree with Lawrence. The colour of the corona should be in most cases orange and the colour of the perianth  between white and yellow.

    Theo

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