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Graft Chimeras - Amazing botanical curiosities · Hydroponics Daily

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  Hello there and welcome back to Hydroponics Daily. I mentioned in a previous
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  post about chimeras and how they can be one of the ways variegated plants can arise.
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  However, I said there are lots more interesting examples of chimeras or chimeras
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  in horticulture and I just wanted to do an episode all about them.
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  And I thought this would be a good time to do it because i
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  like to do a interesting episode
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  about cultivation of plants and then do
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  one about problems or challenges things like that or techniques
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  just to split it up because if it was just like pests diseases problems physiological
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  disorders or equipment equipment equipment it would get quite dull so let's
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  mix it up and have an interesting one about how these obscure plants arise and
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  some of examples of them. I've got three really good examples.
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  So he said that a chimera is named after the Greek mythological monster of the
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  same name that possessed the head of a lion and the body of a goat and the tail of a dragon.
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  I can use chat GPT to answer that. You can enable chat GPT on your iPhone.
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  No, you're okay. I don't want chat GPT. My phone has just decided to have a
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  life of its own. No problem. I won't.
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  Good. I don't know why that came on, but yeah. welcome to
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  my world where chat gpt is trying to take over you can
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  tell from that that this isn't a fake ai
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  voice that's just reading a script from a
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  ai generated prompt because i
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  can keep in nonsense like that so i said chimeras they
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  are plants that are actually separate genetic materials
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  that have been mixed together and they keep their
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  genetic integrity in the individual cells but different
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  cell lines create them really strange
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  looks so he said the chimera you know a a
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  head of a lion a body of a goat a tail of a
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  dragon and a hypothetical chimera plant
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  would have the flowers of a tomato the
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  roots of a potato and the stems of
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  deadly nightshade there's an example keeping the
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  genetics the same but different cell lines different cell structures
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  so they are very very rare and
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  they occur on fortuitous occasions in plants
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  they are not something you can pre-program there's not
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  something you can genetically engineer if you could come
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  up with a way of doing this you would be probably you'd be a rock star in horticulture
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  and plant science in general and you would earn a shed load of money because
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  you'd be able to produce so many wild and wacky different ornamental and edible
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  plants they normally form when a graft union so when you try to graft a plant,
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  put a scion on top of a rootstock.
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  That somehow the cells get mixed up in the graft union and then a stem appears
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  that has got a mix of both the rootstock and the scion cell lines.
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  So it might be the xylem and the phloem are from the rootstock and the bark
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  is from some of the top bit.
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  And then you can propagate them from cuttings. Obviously, you can't propagate
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  them from seeds because they just go back to one single cell line.
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  And the mixed plant all together
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  is called a chimera they're normally they
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  can occur in animals and you can get little rats and
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  mice that have got black fur and
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  white fur mixed together and that's
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  because they're they are like twins that have
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  been mixed together one black head one white head and
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  it can even happen in humans and you can have problems where
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  one of the sort of like the
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  twin organ has issues so they're
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  normally deleterious in animals and humans but in plants they
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  can be wacky just like all mutants can like you
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  know mutants in horticulture they can be prized as unusual this
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  is not a mutation but it is it is a developmental disorder
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  should we say they're not happening as it should be so you
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  you can call it a disorder the first report of a graph chimera came in 1674
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  and that's crazy because that is before that predates any knowledge of genetics
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  and plant breeding 1674 so that's way before mendelew the polish monk who discovered.
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  The way genes segregated and things like that. So Pietro Nati,
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  he was an Italian scientist and the director of Pisa Botanical Gardens.
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  Pisa Botanical Gardens is the oldest botanical gardens in the world, I believe.
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  I'm not reading that from a script from memory, so it might be wrong,
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  but I'd love to go to Pisa Botanical Gardens. Most people, when they go to Pisa,
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  they want to go and see the Leaning Tower.
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  I'd rather go to the Botanical Gardens and see where Pietro Nati
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  first discovered a remarkable chimera which
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  was a well not cross you don't say cross because
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  it's it's not a cross it's a chimera it's
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  not hybridization it was a this chimera had
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  sour orange cells and citron cells
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  so a cross between two different citrus species
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  and that would be you know
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  quite difficult to note because they're both
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  citrus but the most famous example of a chimera that
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  resulted from a graph union is called adam's laburnum so if you know laburnum
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  you know they have bright yellow flowers this plant is a combination of laburnum
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  anogyroides and a broom and brooms are they're both in the bean family or the
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  yeah the bean family the fabaceae.
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  But these are in completely different these are completely different
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  species but also in completely different genuses genera
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  so laburnum anagronoides and chymositis
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  purpurus and purpureus so that's purple one's got purple flowers one's got yellow
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  flowers and it's because it's still essentially two species joined together
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  they cannot have conventionally scientific species names instead adams laburnum
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  it has a little plus before the the genus name so it's plus.
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  Laburnocytosis ademii and the plus indicates its unusual origin and the fact
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  that the graph chimera are still two distinct species is also the reason scientists
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  refrain from using other guarding terms for them like mosaic hybrids mosaic
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  hybrid sounds like it's sort of like a virus,
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  there's a there's a number of different ways of writing the species as well
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  so the majority of the reason why Adam's laburnum
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  is so interesting because for the majority of the branches the
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  laburnum is the dominant influence but the
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  epidermis the skin is composed of cells of
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  the broom so it's easy to
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  spot when it's a flower because the flowers of both species form on the plant
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  and so you can have yellow and purple flowers on the one plant and laburnums
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  have this mass of yellow flowers normally so you get a mass of yellow and purple
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  flowers so that's really interesting.
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  Another chimera, the results from graph union, is the Dalimor's chestnut,
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  and that's called Aesculus plus domestica.
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  And if you see these written down, these scientific names, you'll notice that the plus sign,
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  indicating that it's a chimera, is in the middle between the genus and the species,
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  whereas in Adam's laburnum, it's before the genus name, so you know that that
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  is an intergeneric chimera, whereas this one.
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  Dalimor's chestnut, is a chimera
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  between two chestnut species so it's a
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  less obvious graph chimera as the species providing the
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  tissues in both are chestnuts what can
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  you say about this this is the the chimera is a fusion
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  of cells from the yellow buckeye aesculus flavor
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  and horse chestnut i think aesculus buckeyes
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  are there from like ohio and places like that i'm pretty
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  certain isn't one of their universities named
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  the buckeyes and then horse chestnut i think
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  that is from the balkans so completely different
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  geographically it was discovered in kent in the uk
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  in 1955 by william dallymore a retired director of kew gardens the largest botanical
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  gardens in the world and the tree is characterized by having misshapen crinkly
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  leaves and flowers that appear later than the common horse chestnut there are
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  three different types of Dalimor's chestnut.
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  Despite the unusual ornamental features, they are very rare in cultivation.
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  So if you can find a Dalimor's chestnut and you're doing really well,
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  take a cutting if you can and try and propagate it because it's a very unusual plant.
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  And then a third graph Chimera that can be grown in gardens is a fusion of cells from a hawthorn.
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  So if you know what hawthorn
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  is i'm not going to describe it i can't describe a hawthorn flowers it
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  it goes into leaf really early it's got thorns on it it's also called mayflower
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  and where i live they've got purple flowers but most places they've got white
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  flowers because i live in the midlands of the uk and the midlands hawthorn has
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  got pink flowers and then this graph camera is a cross between hawthorn and meddler.
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  And meddlers are popular down in Kent, near Dover, on the way to France.
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  Meddlers are unusual because it's the only fruit that you have to rot before you eat it.
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  So you allow them to rot before you eat them.
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  And the only place you used to be able to buy them outside of Kent was Harrods
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  in London because they were so difficult to get and so expensive to get in this rotted state.
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  So the name for this graft chimaera is
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  plus cratagomysepolis which
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  means it's an intergeneric chimaera so very unusual so although these are two
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  separate genera they do appear closely related with them also forming a hybrid
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  so you can get as well as the chimaera you can get a hybrid so this one the
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  hybrid would have an x on the scientific name if i haven't lost you all way before this.
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  So that would be X-Crotego mysipolis. So you can get a hybrid of Medlar and
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  Hawthorne and you can get a Chimera.
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  Unfortunately, both the Chimera and the hybrid are rarely cultivated and possibly
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  because the fruit needs bletting, rotting.
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  Bletting is a term for the controlled rotting of fruit and that removes the
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  sort of instringency of the fruit,
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  makes it much more sweeter and the idea of eating
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  partially rotted fruits is not a feature that appeals to many people i've got
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  medley in my garden and i have never eaten it because it's either rock solid
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  or they've rotted to the point where they just look disgusting so i just grow
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  it for its nice flowers and it's a really good pollinator.
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  So that's graph chimeras. They are very rare. They would be exceedingly difficult
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  to attempt to purposely grow, but you can actually create them.
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  So one simple graph chimera that can be achieved is by taking the eye out of
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  a red potato chuba and placing it in the hole made by a white potato chuba that has had the eye removed.
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  You then need to remove the other white eyes from the potato and plant as you
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  would any other sea potato.
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  The resulting plant will produce red, white and blotched and pink potatoes.
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  So that is one graph chimeria you could do in your hydroponic grow today.
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  Take a white potato variety, get an eye off a red potato variety and insert
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  it into where there was an eye on a white potato.
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  Take all the other eyes off that potato, that sea potato and stick
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  it in the ground and grow it and you'll get blotched and pink and mixed and
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  swirled potatoes colored that'd be strange wouldn't it so you could achieve
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  that if you think if you can think of any other chimeras that you would like
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  in an ideal world or other examples of chimeras.
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  Or ways you think you might be able to create them artificially then please
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  get in touch i'm more than happy to do a follow-up episode.
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  A number of chimeras result from mutations in cells in the apical buds of plants
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  and there you can get like a mutant and the wild type growing together.
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  So there they're not mixes of two different genetic materials.
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  Well they are, but one is just a mutant and a non-mutant.
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  So this is where the one cell gets mutated and then gets propagated vegetatively
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  so two good examples of that are the fern leaf beech,
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  and the thornless blackberry. The fernleaf beech produce crinkle leaves due
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  to genetic differences in the epidermal cells.
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  If the bark is damaged, stems without the epidermal cells would grow out and
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  thus the new stems bear normal classical beech leaves.
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  These normal stems then need to
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  be pruned off to maintain the tree in its chimeric and ornamental state.
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  And the thornless blackberry or cori thornless
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  is also a result of mutations in the epidermal cells
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  and this mutation prevents thorns developing so
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  that would be quite nice a thornless blackberry much easier
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  to harvest you grow a crop that's got thorns on
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  it like raspberries rose hips
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  what else try to think of horned thorned
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  crops there are quite a few you could remove them using
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  using this but like the the fern
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  leaf beach the mutation is fairly unstable and needs
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  to be enforced regularly by pruning the thorn stems that
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  arise so they're the the
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  most common chimeras graph chimeras and bud
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  mutation chimeras as i
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  mentioned a couple of days ago when it comes to mutations in
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  apical buds leading to chimera chimeras it's normally
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  a variegated plant that's the most common type of
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  variegation that is produced and
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  propagated for ornamental purposes so hollies
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  are a great example lots of the variegated hollies are chimeras
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  and can't be propagated through the seeds of the hollies and wygela and cornice
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  cornice dogwood they're prone to reversion as well so hollies are stable whereas
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  wygela and cornice they're prone to reversion give you my two two of my best
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  horticultural jokes now.
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  How do you identify a dogwood? By its bark?
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  What's special about its bark? It's rough. Yeah, cornice, the dogwood.
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  Two of my worst jokes, or my best jokes, depending on what you think.
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  And when we say reversion, it's the loss of the mutated cells and the reappearance of the wild types.
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  They just overtake them because they're growing faster. They're photosynthesizing.
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  So reversion is very common in lots of chimeras and mutants and variegated plants.
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  So you need to remove it to keep the ornamental features
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  of your chimeras normally when it's food crops
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  we think of slower growth of variegated
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  or chimera plants as being a disadvantage but if
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  you're growing if you've got ornamental plants like buddlia or rhododendron
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  you might actually want them to be slower growing
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  so you can get variegated forms of buddlia that would grow far far
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  slower you can even get variegated japanese
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  knotweed which is available but massively
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  invasive and problematic even variegated japanese
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  knotweed would be a massive issue i don't know about in america but
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  in the uk it's a highly invasive weed you can't
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  get a loan from the bank a mortgage if your house if
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  a house has got japanese knotweed and it's even a massive weed in japan people
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  say oh it's not a weed in japan we must go and study why it's not a weed in
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  japan i've been to japan and i know that japanese knotweed is a massive problem
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  over there so don't listen to people who say that so yeah and you and you can
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  get reversion in slow-growing plants, slow-growing conifers and things like that.
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  So what else can we say? While graph chimeras are plants containing a mixture
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  of cells from different species, it was found in 2014 that the cells of the
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  graph union of some plants can swap genetic code and even hybridise.
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  So classical science says that can't happen, but in 2014 it was found that they
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  can actually swap genes and sort of do full hybridisation or certainly partial hybridisation.
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  Now, those hybrid cells would normally remain in the graft union and do not
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  form the new plant because they just stay there.
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  They're not being propagated. They're not in the apical meristems that produces
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  the bigger stem and more and more leaves and things like that.
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  But scientists from the Maxplant Institute in Germany
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  found that they can extract the hybrid cells and grow
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  them using micropropagation techniques to produce new hybrids that
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  before would not have been possible by conventional interbreeding using
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  flowering so if you've ever thought of a hybrid and
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  you've read that they these plants can't be hybridized even
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  though even though even though they are
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  closely related then maybe you could try
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  and graft them and then extract the cells from
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  the graft union micro propagate them and you've
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  got a hybrid plant wow if you're
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  a top level micro propagator if you're
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  a keen breeder then i've saved some
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  really juicy good stuff to the end of this episode if
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  you found it useful you thought that was interesting if you
• 17:25
  thought my jokes were hilarious either give me
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  a review or share this podcast with somebody else and
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  if somebody has shared this podcast with you you owe them a very large drink
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  down the pub so go off and buy that person a drink thank you very much for listening
• 17:39
  until tomorrow where i'll talk about probably some sort of pesto disease probably
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  something like downy mildew because we've not talked about that yet and that's
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  a really bad disease so we'll talk about that tomorrow thank you very much for listening goodbye.