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Temperate Fruit & Orchards => Temperate Fruit Discussion => Topic started by: JoeReal on May 16, 2019, 04:33:25 PM

Title: Epigenetics and heritable effects of grafting...
Post by: JoeReal on May 16, 2019, 04:33:25 PM
I do a lot of interspecific grafting (32 species of prunus grafted together), sometimes inter-genera grafting (Eriobotrya, Cydonia, Malus,Pyrus, Crataeugus, Aronia... or Microcitrus, Eremocitrus, Citrus, Fortunella...). I just encountered a scientific paper showing that the grafting combo can alter the grafted plants epigenetically and the result can be inheritable for self-pollinated plants or having true-to-type progenies. I'll have to review this paper again when I have the time. I just skimmed through it. My 160-n-1 tree may have inheritable changes that can be passed on already, either the subsequent scionwood or of course, the seeds from these are dramatically random hybrids.

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0061995
Title: Re: Epigenetics and heritable effects of grafting...
Post by: shaneatwell on May 16, 2019, 05:51:13 PM
A little off topic, but do you know of Glycosmis is compatible with any citrus? Either as rootstock or scion.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: JoeReal on May 16, 2019, 06:00:03 PM
A little off topic, but do you know of Glycosmis is compatible with any citrus? Either as rootstock or scion.

No experience yet with those.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: SeaWalnut on May 16, 2019, 07:49:19 PM
I dont think its possible.Lets say if a plant breeds sexually then it would have the ADN of the father from pollen available to travel and make changes to the mother .In animals and even in humans its well documented that somme ADN of the father passes from the fetus to the mother spine marrow.But animals are a lot more complex than plants.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: JoeReal on May 17, 2019, 12:36:49 AM
I dont think its possible.Lets say if a plant breeds sexually then it would have the ADN of the father from pollen available to travel and make changes to the mother .In animals and even in humans its well documented that somme ADN of the father passes from the fetus to the mother spine marrow.But animals are a lot more complex than plants.

My friend, read up on epigenetics. Itís how we got some of our avocados to become cold hardy and the  trait became inheritable, not only from the subsequent scionwood but also the seeds when some genes were triggered to be expressed from external factors.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: SeaWalnut on May 17, 2019, 06:45:52 AM
Epigenetics its a controversial domain but you know much better than me about grafts and im willing to learn about the issue.Im also interested in genetics of the plants regarding cold hardiness but im following another route by studying plant fossils to havr an idea about the newer species.For example in europe we used to have Dalbergia rosewoods species that now are extinct and i think somme of the extant species today might still have somme of those genes.
The most interesting thing about genetics wich is a mistery ,its why the flora and fauna in China are soo much related to the east American ones.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: pvaldes on May 17, 2019, 07:40:14 AM
> the grafting combo can alter the grafted plants epigenetically and the result can be inheritable for self-pollinated plants or having true-to-type progenies

Epigenetics Is pseudoscience and was not proven. It hangs on the reality that there are external methods for modifying DNA like virus and plasmids, but this is a really small, non functional and normally negligible part. Most accidental mutations and modifications are non heritable  and discarded at gametes level.

If rootstocks would put any trace of DNA on the grafted plants, all new orange cultivars would be hybrids of Citrange at this moment, all new pears would be quince pear hybrids, and all roses would be of pink color. This is obviously not happening.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: JoeReal on May 17, 2019, 10:15:16 AM
Epigenetics its a controversial domain but you know much better than me about grafts and im willing to learn about the issue.Im also interested in genetics of the plants regarding cold hardiness but im following another route by studying plant fossils to havr an idea about the newer species.For example in europe we used to have Dalbergia rosewoods species that now are extinct and i think somme of the extant species today might still have somme of those genes.
The most interesting thing about genetics wich is a mistery ,its why the flora and fauna in China are soo much related to the east American ones.

Wow, very nice!
Title: Re: Epigenetics and heritable effects of grafting...
Post by: JoeReal on May 17, 2019, 10:18:15 AM
> the grafting combo can alter the grafted plants epigenetically and the result can be inheritable for self-pollinated plants or having true-to-type progenies

Epigenetics Is pseudoscience and was not proven. It hangs on the reality that there are external methods for modifying DNA like virus and plasmids, but this is a really small, non functional and normally negligible part. Most accidental mutations and modifications are non heritable  and discarded at gametes level.

If rootstocks would put any trace of DNA on the grafted plants, all new orange cultivars would be hybrids of Citrange at this moment, all new pears would be quince pear hybrids, and all roses would be of pink color. This is obviously not happening.

The evidences aren't very strong for the case of most grafts, especially in the Solanaceous family, but the biomarkers for the resulting progenies and subsequent scionwood means that they can't be dismissed easily either.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: JoeReal on May 17, 2019, 10:37:29 AM
I can understand why many people are skeptical of epigenetics, but last year alone, there are more than 2,500 refereed scientific articles alone that dealt with it. Some of my friends with graduate or medical degrees have specialized on it and produced irrefutable results and even commercial products. So for me, it can't be dismissed. I even witnessed several instances of cold hardy avocados resulting from environmental stresses, right in my backyard and other people, and that's why I was able to grow and fruit avocados in our area.  Recently I evaluated a tree of my friend, and have found a potentially Cold Hardy Hass Avocado, which resulted from the arctic blast event about a decade ago and the tree is producing Hass type avocados and was never damaged by any frosts for the past 4 years or so, and has increasing yield each year. I have added it into my collection. I have discussed the details in other forums and I can link it here.

Here's the perception about epigenetics: 
https://www.nature.com/articles/nature05913 (https://www.nature.com/articles/nature05913)

And there are about 318,000 hits in Google Scholar for epigenetics.

And in the National Institute of Health Biomedical Databases, there are about 29,692 recent articles that talked about epigenetics.
https://www.ncbi.nlm.nih.gov/pubmed/?term=epigenetics (https://www.ncbi.nlm.nih.gov/pubmed/?term=epigenetics)


Title: Re: Epigenetics and heritable effects of grafting...
Post by: pvaldes on May 17, 2019, 12:29:58 PM
The problem is that the term is often incorrecly used. Epigenetics in the sense of: "if I stand in a hot bath my children will inherit hot resistance" is just a different name for Lamarckism, that is a rebutted theory.
Title: Re: Epigenetics and heritable effects of grafting...
Post by: NateTheGreat on May 17, 2019, 06:06:08 PM
https://en.wikipedia.org/wiki/Phenotypic_plasticity
https://en.wikipedia.org/wiki/Baldwin_effect
https://en.wikipedia.org/wiki/Genetic_assimilation

From my understanding of these concepts, the cold-hardy avocado after an arctic blast would be an example of Phenotypic plasticity. If you were able to breed affected plants and cause the change in genetics to become stable, without requiring the environmental stress to activate, I believe that would be Genetic assimilation, but it might be more accurately described as Baldwin effect.

Just because it resembles Lamarckism doesn't mean it is.

See also:
https://en.wikipedia.org/wiki/Maternal_effect
https://en.wikipedia.org/wiki/Phytoplasma