Does ploidy level influence graft compatibility?

Does ploidy have any impact on graft compatibility? If plants of different ploidy levels are grafted are they less likely to be compatible than if they are the same ploidy level?

I read something where grafting tea (Camellia sinensis) plants it was preferred to use the same ploidy level due to cell size etc. Grafting triploid scion onto diploid rootstock still worked, but the failure rate was higher when different ploidy levels were used.

When it is different species being grafted, the cell size, growth rates etc already don’t match, so would grafting diploid to tetraploid for example have any less chance of working than if they were both diploid?

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We know Triploids are sterile and diploids are not. Triploids in my experience grow faster. I’m very interested to research this it’s fascinating.

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Great question. I’m interested, but I don’t know where to start looking.

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This question is still open years later. Who's Growing Improved American Persimmons? Suggestions welcome! . We move on now to discuss these same questions about 60 and 90 chromosome persimmon. Which graft easier? Cross pollinating becomes complexed. Persimmons | Center for Crop Diversification

" Persimmons

The American or common persimmon, Diospyros virginiana, is a slow growing, moderately sized tree native to Kentucky. Fruit are about 1 to 2 inches in diameter. Unripe fruit, which is high in tannins, has a bitter astringent flavor. The golden orange to red fruit are very sweet when fully ripened and astringency is reduced. Cultivated varieties may have improved quality and lose their astringency earlier in the fall.

Marketing

Persimmon fruit on treeThe Asian persimmon, which is not winter hardy in Kentucky, is more commonly grown commercially in U.S. orchards. There are ongoing efforts to commercialize the American persimmon. These trees are normally sold by nurseries that specialize in less common fruits and nuts. Interest in persimmon and other native fruits has increased with more emphasis on local, regional and “slow” food. Fruit may be marketed fresh, and persimmons are occasionally found at farmers markets across Kentucky. Persimmon can also be processed and the pulp sold as a frozen product. Value-added products include persimmon puddings, cookies, cakes, custards, ice creams, sherbets and preserves. Fruit may also be dried. Producers marketing persimmons at farmers markets and other direct marketing channels should provide persimmon storage, ripening and use information, as many consumers are unfamiliar with the crop.

Production

Persimmon blossomPersimmon cultivars vary in fruit color, size, shape and astringency. Earliness and tree size may also differ among varieties. Fruit of most varieties contain black flecks in the pulp, which are not attractive in the processed product. ‘Prok,’ ‘Killen,’ ‘Claypool,’ ‘I-115,’ ‘Dollywood,’ ‘100-42,’ ‘100-43,’ ‘100-45,’ ‘Early Golden,’ ‘John Rick’ and ‘C-100’ are excellent varieties that contain few or no black specks. Persimmons are normally dioecious; that is, trees produce either male or female flowers on separate trees. There is a 90-chromosome American persimmon that is native to the northern U.S. and a 60-chromosome type that is native to Kentucky and the southern U.S. Most of the named varieties are of the 90-chromosome type that set fruit parthenocarpically, without pollination. Thus pollination is not necessary for the 90-chromosome type and fruit are easier to process with few or no seeds."

https://www.orangepippintrees.com/articles/fruit-tree-advice/triploid-apple-varieties
" Triploid apple varieties

Most animals have two sets of chromosomes, inherited from the mother and father respectively, and are known as “diploid”. This is true of many plants too, including the majority of apple varieties. However several important apple varieties have three sets of chromosomes rather than two, and are known as triploids.

Triploid apple varieties have a couple of important characteristics which need to be considered when growing them:

  • Their pollen is effectively sterile and cannot be used to pollinate other apple trees.
  • They are usually not self-fertile, and therefore need another compatible apple variety nearby to pollinate them. (Some triploid varieties have a degree of partial self-fertility).

In short, if you are planting triploid varieties, it is best to to make sure you have the necessary pollinator trees nearby. You will need either one self-fertile apple variety (or crab-apple) or two other varieties which can cross-pollinate each other as well as the triploid variety.

Although the pollination requirements might be inconvenient, triploid varieties have several advantages which make them desirable for the home or community orchard:

  • They usually produce vigorous trees, which can support large crops.
  • The apples are often quite large.
  • They usually display a good degree of natural disease resistance.
  • They can often survive in difficult conditions.

It is perhaps no co-incidence that many well-known heritage apple varieties are triploids, because our ancestors would have found their large size and productivity very useful. Some of the best-known triploid varieties are:

Ploidy comes up not just with grafting but also height , precocious, etc. Persimmon ploidy impact on height

jashs-article-p609 (1).pdf (125.0 KB)

" Japanese persimmon (Diospyros kaki) is a hexaploid tree fruit having a somatic chromosome number of 90 (2n = 6x, x = 15)."

Work is being done with kaki Allele-aware chromosome-level genome assembly of the autohexaploid Diospyros kaki Thunb - PMC

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Re: apples- I haven’t heard of any compatibility challenges with triploids onto diploid rootstock. Just now my mind led to considering if anyone has explored trying to come up with a semi-dwarfing or dwarfing triploid rootstock for disease resistance and vigor.

Along with the topic of persimmons and Diospyros in general as mentioned above by Clark, what I am currently trying to figure out is Asimina triloba. Mr Sam Norris (no longer with us) worked with colchicine to attempt to adjust ploidy of pawpaw seedlings with the hope of creating seedless F2 progeny after a back cross with the ‘standard’ diploid flowers.

It’s my understanding that certain pawpaws with genetics passed down from Mr Norris’s seedlings have a higher rate of graft failure. The most noteworthy amongst them being 250-30, for example.

The more I learn, the more I realize there is to learn…

A note about colchicine- it is very much a TOXIC chemical in a literal sense (not an organic grower talking about synthetic chemicals or growing things in plastic being ‘bad’ sense) and extreme caution should be exercised when considering using it. It’s my understanding that Mr Norris may have had some health complications related to his experiments which might have contributed to his passing. This has not been confirmed.

PS- Clark, I think the persimmon challenges may be more due to other factors as @Hillbillyhort and others mentioned. This could absolutely be the case for the pawpaws too. So many variables… Persimmon wilt - #4 by Hillbillyhort

The polyploid pawpaws are curious for sure. I haven’t grafted many of Jerry’s polyploid varieties yet. I thought that 250-30 was a seedling of Atwood(KY 8-2) according to Cliff’s website. Jerry’s Big Girl 250-39 is (Sunflower x Sam Norris 15) again according to Cliffs website.

I have wondered if the Sam Norris trees are tetraploid, and they cross with a Diploid that would make the offspring Triploid right?

What would you get if you crossed a triploid with diploid pawpaw?