Author Topic: Using approach grafting to graft more genetically distant trees?  (Read 805 times)

lajos93

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Using approach grafting to graft more genetically distant trees?
« on: December 15, 2022, 10:54:13 AM »
Ive read that with approach grafting you have less chance for graft incompatibility to occur
Does that only include cheimical incopatibility (virus, fungus attack) or when a more genetically distant scion is used?

To be more concrete...  would it be possible to graft avocado on red bay this way? (Both are in the lauraceae family)
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Finca La Isla

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #1 on: December 15, 2022, 04:02:19 PM »
I think that some grafts that are very difficult to do could have a better chance of success using an approach graft because both the rootstock and the scion are living. But the compatibility issue will be the same.
Peter

pagnr

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #2 on: December 15, 2022, 04:22:41 PM »
I think that some grafts that are very difficult to do could have a better chance of success using an approach graft because both the rootstock and the scion are living. But the compatibility issue will be the same.
Peter

Agree the incompatibility will be the same, but the time frame is longer, so the graft won't die as quickly as in the normal detached methods.
There is more chance of success with time.
Apart from approach grafting, Inarching is a similar process, using another rootstock to support a struggling tree with root rot or graft union incompatibility.

In Citrus when distant species are used as rootstocks, sometimes leaving a few branches live on the rootstock section, is known to keep the rootstock functioning better long term. This would have to be watched closely. In normal Citrus grafting letting rootstock suckers take over can cause graft decline.

In nature there are numerous cases of live trees of very distant species grafting together where branches cross and making strong unions.
The roots of both trees remain alive and the two trees grow connected for many years.
Underground root grafting is similarly common but unobserved. Possibly more common than suspected.
Recent work suggests the underground root linkage is a highly complex chemical feedback communication system.
« Last Edit: December 16, 2022, 02:23:14 AM by pagnr »

lajos93

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #3 on: December 16, 2022, 01:26:56 AM »
what if you let it live for years then cut it off, when the strong connections are made already?
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Galatians522

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #4 on: December 16, 2022, 09:50:25 PM »
I thought the same as you about approach grafting. It may not work that way in every situation, though. Some studies on vegetable grafting for example indicate that there is a higher degree of success with cleft grafting when using genetically distant specie Maybe that is because they are annuals and tree crops would be different? The specific combination you mentioned (avocado on red bay) has been tried before. The researchers got a tiny amount of growth and that never did anything and eventually died. Then, they tried hybridizing the two. As I recall, there were over 2,000 polination attempts that ended in failure. Reading the article was enough to convince me not to try it.

pagnr

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #5 on: December 16, 2022, 10:39:23 PM »
Then, they tried hybridizing the two. As I recall, there were over 2,000 polination attempts that ended in failure. Reading the article was enough to convince me not to try it.

There are more possibilities now, with somatic hybridisations or even more refined techniques to combine the two species.

if you could graft Avocado onto red bay, you still face the problem of the fruiting portion being exposed to very cold temperatures where red bay is tolerant.
Grafting Citrus onto cold tolerant rootstocks does impart some extra cold protection to the scion. Some of this is because the rootstock is a deciduous/dormant plant.
That may not apply to red bay/ Avocado ?

lajos93

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #6 on: December 17, 2022, 11:03:44 AM »

There are more possibilities now, with somatic hybridisations or even more refined techniques to combine the two species.

if you could graft Avocado onto red bay, you still face the problem of the fruiting portion being exposed to very cold temperatures where red bay is tolerant.


Youre talking like this could be a possibility?
Could it be that it has been done already with these new crossing techniques somatic hybridization/protoplast fusion ?

I mean it should be possible since these technologies are exactly what they are for, they are not close enough for natural cross breeding but not too distant for this to not work at all
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Galatians522

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #7 on: December 17, 2022, 07:34:50 PM »
I believe the use of protoplast fusion to combine species that are too distant to hybridize naturally is illegal in most countries. For example it would not be legal to combine an oak and a chestnut--even though they are related they can't hybridize. However, it would be allowable to fuse a plum and an apricot because they can hybridize (even if it is a bit difficult). Someone can correct me if I am wrong.

Walt

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #8 on: December 17, 2022, 11:45:23 PM »
I've never heard of it being illegal in the USA. Is there anyone here who keeps up on these things?  It's been 40 years since I was up to date on this.

pagnr

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Re: Using approach grafting to graft more genetically distant trees?
« Reply #9 on: December 18, 2022, 03:32:56 AM »
I have not heard of it being illegal as far as plants are concerned. It seems quite commonly used.
I'm not sure many scientists would "Bat an Eyelid" ( pun intended ) over the issue.
There may be ethics questions about using the techniques with animal cells, as most creatures have some recognised level of sensation and instinct, that could be highly interrupted in a hybrid.