Genotype, phenotype, and genetic drift.

S

SpiritFarmVa

Well-known member
This topic has surfaced in several other threads and deserves its own.

This video from Lou Monti discusses human selection of propagation material for continual phenotypic improvement.


It makes you think about the synonyms in figs, ones that are close but seem to be just enough different that you think it is a different variety.
Or is it just over time it was selected to be better and better, but ultimately they are genetically the same. Is it likely that many very similar figs are genetically different? Certainly , most likely there are.

We have experienced trees that one of the same variety out performs all others, even though the original plant was the same. As it was multiplied one started to really stand out.
So if we now only multiply from this better phenotype and when a piece of it stands out, select again. Make that the mother, on and on and on, could you shift the cultivar over time to be more what we want? Could you shift a tree far enough some would say it’s a different cultivar?

Would phenotypic selection be a better way than breeding to more rapidly get improved plants? Especially if you combine it with grafting io to rootstocks that improved some part of performance.

There are many things this topic brings to mind. Including should mother plants be continuously replaced as you make selection improvements.

Also how many “sports” are really “sports” or just phenotypic improvement in the branch. Unless it is radically and obviously different ie fruit color changes, or variegation.

It will be interesting to see what others have considered in regards to this subject.
 
I love this subject. I believe phenotypes do not come up as often as they should in fig cultivation. For one reason we're just not doing enough cuttings of the same cultivar to spot a superior phenotype. I brought up @Figgin' A miraculous VDB. Also forbiddenfruit.Garden amazing WM that he has named the Beast as to Superior phenotype that seem to be breeding true. It's my experience that quite often a superior phenotype will retain its characteristics. It's not a popular subject, you may not get very many responses to this thread, but I will pursue the subject with you, because it is a righteous one. Superior phenotypes appear much more often in hemp cultivation because hemp Growers will often take hundreds of cuttings of the same variety. This rarely happens with fig cultivation.
 
Genetic drift is another subject I believe in. But it is less popular amongst hemp Growers. Or when does a superior phenotype become a variety in and of itself. It certainly happens but not as often. With fruit Orchard Growers it's often a branch that is a sport of the original variety. It needs to be air layered to become a sport in its own right. Many of the red fleshed apples started in this way.
 
The beast WM was what made us decide to post this topic.
It definitely needs more input and exploration.

Figless said:
Or when does a superior phenotype become a variety in and of itself.
Click to expand...
Or should it replace the genetics of the genotype.
Why should we continue a genotypes poor expression when there is a superior phenotype that is genetically identical.
In seed growing cultivators rouge out poor material, looking to improve the line.
Should we not do the same? It’s definitely something to think about.
 
As more research goes into this topic it seems like as growers you drift your cultivars to the better or to the worse. If more intentional propagation was done we could keep cultivars constantly improving.
 
This is a very interesting article. If I understand it correctly, it seems to suggest that the only the original “mother plant” can continue to produce the same cuttings and the further you are removed as cuttings are taken from new trees and passed on, the more “drift” there is. Which would suggest that getting a cuttings from the original mother tree is the only real way to assure you’re getting a good approximation of the tree you want

cannatechtoday.com

What is Genetic Drift and How Does it Apply to Cloning and Micro-propagation?

"Genetic drift" is often used to describe change in appearance/behavior of a clone variety over time. However, this may not be the correct use of the term.
cannatechtoday.com cannatechtoday.com
 
In the section that they define genetic drift they say the observed differences are not actual genetic changes. But other variables negatively affecting the plant. (That’s how I read it at least)
I see the mother as the starting point not the ending point. And as a backup in case the clones fail. Even the mother will have poor material to clone. So it is up the propagator to select the best cloning material. Disease, insect pressure, poor growing conditions can all weaken a plant.
Eventually something will kill the mother plant. So if the line is to be kept going, the best material with the most desirable traits should be retained. That’s the way I look at it.
What makes me think about this topic so much is the clear observable differences seen in the same cultivars of figs. Like the Garrett VDB that figgin’A has. Is it any less VDB because it’s many generations form the mother? Genetically it’s identical, phenotypically it’s superior.
So that’s the rabbit hole😁.
 
Figless said:
I love this subject. I believe phenotypes do not come up as often as they should in fig cultivation. For one reason we're just not doing enough cuttings of the same cultivar to spot a superior phenotype. I brought up @Figgin' A miraculous VDB. Also forbiddenfruit.Garden amazing WM that he has named the Beast as to Superior phenotype that seem to be breeding true. It's my experience that quite often a superior phenotype will retain its characteristics. It's not a popular subject, you may not get very many responses to this thread, but I will pursue the subject with you, because it is a righteous one. Superior phenotypes appear much more often in hemp cultivation because hemp Growers will often take hundreds of cuttings of the same variety. This rarely happens with fig cultivation.
Click to expand...
I would love to do this, except that my collector mentality won’t allow me to have only one variety even if it would be for experimentation with this idea - I guess it’s too much fear of missing out on other types that keeps me from being content with just one even if that one is excellent, or even “the best”…
 
If I read it correctly, the article suggested to me that they would take cuttings from the mother plant, and they would always be good and true… However, when the plant became too old to take cuttings from and they began to use cuttings descended from the original mother that thing started to change…. and that the further those descendants were from the original… The more significant to change would be.

But you point something out of very interesting even if it’s not technically “genetic drift“. That is that the change is not necessarily a “problem“ but perhaps a beneficial characteristic.

Also, interesting that a lot of with this article is to point out that it’s not “genetic drift“ that is the change. Rather that the jeans are the same, and that they are arranged differently… At least I think that’s what it’s getting at
 
TorontoJoe said:
If I read it correctly, the article suggested to me that they would take cuttings from the mother plant, and they would always be good and true… However, when the plant became too old to take cuttings from and they began to use cuttings descended from the original mother that thing started to change…. and that the further those descendants were from the original… The more significant to change would be.

But you point something out of very interesting even if it’s not technically “genetic drift“. That is that the change is not necessarily a “problem“ but perhaps a beneficial characteristic.

Also, interesting that a lot of with this article is to point out that it’s not “genetic drift“ that is the change. Rather that the jeans are the same, and that they are arranged differently… At least I think that’s what it’s getting at
Click to expand...

I will need to probably read the article several times to pick up all of it.

I do see multigenerational changes as potentially good or bad. Just depending on the propagators selection and growing conditions. We know mother plants will all eventually be gone. So as we perpetuate the cultivar, We should select toward improvement. If you aren’t going forward you are going backward as they say.
 
Ikibahd said:
I would love to do this, except that my collector mentality won’t allow me to have only one variety even if it would be for experimentation with this idea - I guess it’s too much fear of missing out on other types that keeps me from being content with just one even if that one is excellent, or even “the best”…
Click to expand...

Most of this type of work is done by universities, because of the cost and space requirements.
Collectors be collecting😁
 
Collections are quite important to breeding programs. As old genetics would be lost without them. As varieties of fruits have come in and out of fashion with commercial growers the varieties would be lost to history.
Breeding programs often seek out old genetics to breed traits into new varieties.
( it’s been mentioned in vegetable breeding and apple breeding material I’ve seen)
 
I currently have three cuttings of these Superior phenotypes. The Beast WM probably would be better received by getting a cutting from the original mother tree. I'm at least a year away from providing cuttings of the WM Beast....Lou Monti certainly has a possible Superior phenotype BM. If you look at his videos his BM is the size of a fairly large tree. If somebody has a cutting of this giant BM phenotype I would love to know about it. About 6 months ago he threatened to distribute cuttings of his trees but I don't know that that ever happened maybe Teresa would know. I will continue to hunt them down one by one and then make the Superior phenotype Library available to our fig fanatic membership.
 
Does anyone know about somaclonal variation? Can or does it occur outside of tissue culture? I am just staring into this topic and have no knowledge of it.
 
SpiritFarmVa said:
Does anyone know about somaclonal variation? Can or does it occur outside of tissue culture? I am just staring into this topic and have no knowledge of it.
Click to expand...

I don’t but now you have me looking into it.

I’ve always wondered why some varieties I get seem to drastically under perform given I know and trust the source, so this topic really interests me
 
Definitely hoping more knowledgable folks are able to input here. It is fascinating and makes you start to think about why some material ends up so different. It is going to be a bit of reading for sure. Apparently in tissue culture plants actually spontaneously rearrange dna. Resulting in essentially a sport I guess. And the resulting new material can be grown stably through vegetative propagation.
 
You must log in or register to reply here.
Back
Top