Breeding techniques

oscar the rotund said:
I didn't read that as Epigenetics. Notice he said "acquired traits". I read it as the traits acquired during a long period of time grown in a particular environment. That's not Epigenetics. For an example of Epigenetics I read a report where GA3 was sprayed on plants and the next generation had better growth patterns due to GA3 on the previous generation.

Burbank did say that the plant carries millions of years of it's heritage within it. Could be. How much information can the genes of a pea carry?
I don't know the answer but it's a large number.
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I think you may be right about that Oscar, its hard to say. My point is that even if he did believe in acquired inheritance, it does not have much impact on the practical application of his methodology.


GITT, that's a good point, We could and we should. I am not trying to belittle science, or detract from its importance in application to breeding. However with that said, a gas chromatograph will never be a viable substitute for a nice glass bong, packed with ice.
 
joshuahazen said:
The truth is Breeding is an art more than it is a science, Although science is a very valuable tool in this art of breeding, and plays a critical role.


While science is a very important tool in breeding, it is not the most important tool. I would say it ranks 3rd in importance, when we are discussing the tools of breeding.

The Most important tool, is of course the breeder's ability to determine what is the best. His ability to select the best, ie his taste, and his knowledge and experience of the strains he is working with.

The next most important tool, is his access to genetics, and the genetics themselves. What did he start with, most often this equates to: Who does he know. Thanks to folks like Nevil and Shanti, even someone who doesn't know anyone, can still access elite genetics. I rank this second, only because if you lack the most important 1st tool, you will never be able to determine what genetics you are looking for in the first place, and once you have them you won't be able to determine what to select from them.

Scientific knowledge comes in a distant 3rd, in terms of importance, behind these two. And even then, the breeder does not need to know so much about science, to properly utilize the scientific method in breeding. Luther Burbank is evidence of this. And his lessons aren't that complex, really. He seems to be saying and demonstrating essentially the same thing, over and over and over again.

That is why Nevil is the Grandmaster of dope, as arguably the most influential modern breeder of cannabis. It his taste and knowledge of the strains, first and foremost which made him thus, then his access to genetics 2nd...
Of course his extensive scientific knowledge and capability, while not as important as the other two components, still played a critical role...
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Great post...

I entirely concur with that.

I never heard the best grape breeders were scientists...lol

Peace.

K.
 
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I never heard the best grape breeders were scientists...lol
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probably why even one of the oldest vine varieties is extremely unstable.. that being Pinot Noir and its various guises. hence they grow large numbers out and collect the clones that suit.. if thats the way then we should be polyhybridizing and just getting the big hetero plants that suit.... though this does suit some!!!
 
oscar the rotund said:
I didn't read that as Epigenetics. Notice he said "acquired traits". I read it as the traits acquired during a long period of time grown in a particular environment. That's not Epigenetics. For an example of Epigenetics I read a report where GA3 was sprayed on plants and the next generation had better growth patterns due to GA3 on the previous generation.

Burbank did say that the plant carries millions of years of it's heritage within it. Could be. How much information can the genes of a pea carry?
I don't know the answer but it's a large number.
Click to expand...

It is my personal belief that every trait acquired by any organism through the influence of its environment becomes a part of the condition of the organism that tends to reproduce itself through inheritance. In other words I entertain no doubt that all acquired traits of every kind are transmissible as more or less infinitesimal tendencies to the offspring of the organism.
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Epigenetics is just that the response to the enviroment!!! what you need to decipher is weather you are just selecting phenotypically for the genes reaction in that given enviroment hence when grown in different enviros plants respond differently, so most likely your selection would be different... hence burbanks belief that with more genes the more a plant is fit for adaptation!!! but we will be back to pheno plasticity of which burbank believed there was a limit... next step quantitives
 
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GreenintheThumb said:
Dr. Harold P. Olmo wasn't a scientist? What grape breeders have you even heard of?
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Some of the best-known hybrid grape breeders include:

Francois Baco(Teacher): responsible for the development Baco noir

J.F. Ravat(civil engineer): known for Vignoles (Ravat 51)

Elmer Swenson(farmer), of Wisconsin, breeder of St. Croix, St. Pepin, La Crosse, Esprit, Edelweiss (grape), Swenson Red, and Kay Gray among others.

T.V. Munson(horticulturist) the savior of European viticulture and the father of rootstock breeding, released dozens of cultivars and contributed greatly to the knowledge of wild American grape species.

Peace.

K.
 
kashrocks said:
Great post...

I entirely concur with that.

I never heard the best grape breeders were scientists...lol

Peace.

K.
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Right on Kashrocks,
Thanks.



Well I think it is not necessary to be a scientist, if you are a breeder, although many breeders are scientists to some degree, especially if they if they are indoor growers utilizing a strict horticultural discipline. Even many growers who don't breed, often utilize the scientific method on a regular basis.

You certainly do not have to have a degree in science to practice science, or utilize the scientific method. Certainly Burbank was a scientist, with over 100,000 recorded experiments under his belt.

Nevil is obviously a scientist.

Have you ever done a controlled experiment in your growroom? Most breeders and even most growers frequently do scientific experiments in their grows on a regular basis.

Lets look at the definition of scientist from several different dictionary sources:

sci·en·tist
noun \ˈsī-ən-tist\
Definition of SCIENTIST
1
: a person learned in science and especially natural science : a scientific investigator

Scientist - Definition and More from the Free Merriam-Webster Dictionary




*

American Heritage Dictionary:
sci·en·tist
(sī'ən-tĭst)
n.
A person having expert knowledge of one or more sciences, especially a natural or physical science.


scientist: Definition from Answers.com



scientist [ˈsaɪəntɪst]
n
a person who studies or practises any of the sciences or who uses scientific methods


scientist - definition of scientist by the Free Online Dictionary, Thesaurus and Encyclopedia.





I think the latter definition is the most concise and to the point.

I don't see a single definition that states that an individual has to have some sort of degree, to be a scientist.


Well lets take a closer look at the scientific method. Here is a simple, good definition from Mirriam-Webster.

Definition of SCIENTIFIC METHOD

: principles and procedures for the systematic pursuit of knowledge involving the recognition and formulation of a problem, the collection of data through observation and experiment, and the formulation and testing of hypotheses.

First Known Use of SCIENTIFIC METHOD
circa 1810

Source: Scientific method - Definition and More from the Free Merriam-Webster Dictionary



That is exactly what most of us indoor growers are doing constantly whether we realize it or not.

For example, how many controlled experiments have you done in the last year?
An example of a controlled experiment: Testing a new clone. Whether dirt or hydroponic if the grower is maintaining constant variables, ie same proximity towards light, same soil or medium, same nutrient solution, same ratio, ph, and light cycle, the only variable he has changed is the genetics of the clone he is using, and he is recording his results, then he is performing a scientific experiment. If he does this kind of thing on a regular basis, and the result is, he is constantly improving his grow in ways that can be quantified and measured, guess what? He is utilizing the scientific method, and as far as his grow is concerned, he is a scientist.

The problem would be: How to get higher yield and more potency from his grow.

So he tests a bunch of new clones, it seems one does very well is much heavier, and it is certainly better quality than the one he is using now .
so he forms the following hypothosis: He will get a higher yield of superior weed if he uses the following pre tested clone.

So he does another test, and this time he uses 6 of the new clones and he gets a much higher yield from these 6.

Then he does one final test switching over on the next grow and does his entire grow exclusively of the new clone and sure enough his yield is almost twice as much.

He records and documents these results.
He has successfully proven his hypothosis to be correct and now it becomes a full blown theory.

He successfully utilizes the scientific method and his new theory to increase both the yield and potency of his garden.
 
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joshuahazen said:
You certainly do not have to have a degree in science to practice science, or utilize the scientific method. Certainly Burbank was a scientist, with over 100,000 recorded experiments under his belt.

Nevil is obviously a scientist.
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You are right...

I should have say that I never heard that the best grape breeders were geneticists.:)

Thank you.

Peace.

K.
 
kashrocks said:
Some of the best-known hybrid grape breeders include:

Francois Baco(Teacher): responsible for the development Baco noir

J.F. Ravat(civil engineer): known for Vignoles (Ravat 51)

Elmer Swenson(farmer), of Wisconsin, breeder of St. Croix, St. Pepin, La Crosse, Esprit, Edelweiss (grape), Swenson Red, and Kay Gray among others.

T.V. Munson(horticulturist) the savior of European viticulture and the father of rootstock breeding, released dozens of cultivars and contributed greatly to the knowledge of wild American grape species.



Peace.

K.
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No they just NEED the scientist/geneticists to help them bred for disease resistance crops and to improve yield etc.... if you look at the breeding of grape its not too far removed from its ancestors... we know this because of SCIENCE!!! we know how to improve the crops because of SCIENCE...

Update from the Grape Breeding & Genetics Conference: Future vines without powdery and downy mildew?

10th International Conference on Grapevine Breeding and Genetics

Genetic structure and domestication history of the grape

A huge plus for breeders, producers—and the rest of us: plant genomics research - page 2 | Agricultural Research
 
As mentioned above by Joshua Science is definitively a useful tool...

But this is far from being the only quality requested to be a good breeder.

The good breeders are those who have good scientific knowledge but who above all are truely passionnate by what they do.

Peace.

K.
 
kashrocks said:
As mentioned above by Joshua Science is definitively a useful tool...

But this is far from being the only quality requested to be a good breeder.

The good breeders are those who have good scientific knowledge but who above all are truely passionnate by what they do.

Peace.

K.
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I must agree.
:D :D :D
 
Don't worry guys, scientists are never passionate. They just spend their lives studying what interests them because of the HUUUUGE paychecks. Cold, non-feeling robots is what scientists are.

Really this whole line of thinking is hilarious. I'm ganna go ask a janitor to list the important tools needed to be a great architect. Then I'm ganna post on the internet about it. Stay tuned!
 
I am a scientist and I am passionate. What about you GITT, you seem like a pretty passionate guy to me, sometimes to a fault.

But I don't see the contextual veracity of your analogy, we are breeders discussing the importance of various components of breeding, in a thread titled "breeding techniques".
 
hi fellows,

personally i have never seen their work nor smoke it so......im a bit like St Thomas if you know what i mean :D
 
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Experience wins over knwledge every time but having a good bit of knowledge can enhance the experience.

The best breeders are breeders and the best sientists are scientists

Traditional thinking can sometimes be a disease in the year 2011 why shouldn`t we apply scince to plant breeding

If it doesn`t involve capitalism then i cant see it doing no harm!!
 
Experience tempered with knowlege and science for the win everytime id say ...
 
sorry for not reading the last 89 pages,,,

hopefully this makes up for it,,:)


CuzinDave said:
Sam, I should have metioned that my argument was based on my recollections of constructing those statistical tableaus with Ne on the left hand side and very small numbers on the top of the matix.So your argument about Ne at 2000 would be correct insofar as preserving almost all of the alleles. Anyways doing too much math makes my head hurt. The little ^ symbols I used are exponentials.
There are methods for estimating the probability of genetic drift and underscoring its devastating impact on unsystematic shifts in allele frequencies where Ne is small.
The formula is: Prob. = (1 - frequency) ^ 2 ^ Ne
For example, lets say there is a less common allele (w) in a white widow clone that occurs say 5% of the time (.05) and further for arguments sake Ne = 2.
So. (1.- .05) = .95
(.95) ^ (2)(2) = 81.4% probability of elimination
Make Ne = 50
(.95) ^ (2)(50) = .00592 probability of elimination.
As is the case with any algorithm, the answers will change depending upon what numbers one intends to plug into the formula.
The higher the frequency of an allele in a given population the greater its likelihood of surviving a genetic bottleneck with the opposite being true of lower frequency alleles surviving when Ne is very small.
To expand on the basic concept of Ne one must consider how Ne effects the F statistic (Coefficient of Inbreeding).
So let's assume an NE of say 4. The decline in heterozygosity or rate of inbreeding at from the first generation would be: F1 = (1) / (2 * Ne) or 1 / (2 * 4) = .125.
With each subsequent generation the decline in heterozygosity is cumulative. Take generation F6
F6 = 1 - (1 - F1) ^ 6 = 1 - (1 - .125) ^ 6 = .551
By the 6th generation 55% of the genetic diversity will have been lost in the line. By the 12th generation 1 - (.87.5) ^ 12 = 80 % of the genetic diversity will have been eliminated.
The larger the Ne the lower the rate is the actual loss of diversity through inbreeding.
Let's take a hypothetical example:
Breeder X grows out 20 plants and gets 6 males and 14 females.
Effective breeding population will be:
(4)*(6)M*(14)F / 20 Plants Total =16.8

Change in inbreeding per generation:
1 / (2)*(16.8)= 2.9%

The "best" effective size calculation in this example:
16.8/20 = 84%

Fun with numbers for sure. I posted these examplea to underscore that genetic drift is quantitatively measurable.
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"the most useful measure of homozygosity is the inbreeding coefficient, F. This coefficient takes a value near zero in most large random-mating populations, and the coefficient increases toward unity under sustained genetic assortive mating. Self-fertilization (one individual in each generation in each family) leads to very rapid increases in homozygosity. Starting with a heterozygote (F=0.50), F takes the values 0.75, 0.875, 0.9375, 0.9688, 0.9844, 0.9922, ... in successive generations of selfing, thus exceeding 0.90 in the third generation. Under continued mating of 2 individuals per family (full sibs) each generation, F is not expected to exceed 0.90 until the eighth generation. With continued mating of 4 individuals per family (double first cousins), F is not expected to exceed 0.90 until the seventeenth generation and rates of increase in F with 8 individuals per family (quadruple second cousins) and 16 individuals per family (octuple third cousins) are much slower yet. The rate of increase in F is so slow with more than 16 mating individuals per family per generation that such matings are of essentially no consequence in concentrating favorable alleles in selection programs in outcrossing species. It is therefore not at all surprising that breeders of plant species nearly always choose schemes featuring very close inbreeding. Selfing schemes (one parent/generation) are by far the most common in breeding outcrossing plants, and the usual goal is to develop numerous highly homozygous lines that are first evaluated by top crossing to identify lines with good general combining ability, followed by testing specific combinations of pairs of lines to identify the very few pairs that have the potential to produce truly excellent single-cross hybrids."

Robert Allard
 
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