Everybody a breeder ?

[Nunsacred]

Tom :

Traits are governed by gene expression, which usually isn't bi-allelic Mendelian.
Therefore science can't measure or predict trait inheritance until we know how to even start analysing RNA expression profiles real-time.
Even then it's probably different rules for each individual karyotype and therefore still down to population/pool size and hindsight.

Testing self crosses, there's some logic to it, I agree it's better than nothing, it's a good practice, even, but it's not always better than trying other plants instead, basically increasing your population size.
Especially for anyone who doesn't really know the traits in their lines well.

If you think you can beat luck based on 'like begets like' then that's fair enough
but making out that this is scientific is a bit rich.
Like when cosmetics adverts call lip gloss a 'system'.

 

[xmobotx]

nunsacred let me see if i understand this correctly then; utilizing a selection process and criteria to isolate candidates based on desired traits is roughly equal to running way high plant counts and just letting nature take its course?

is that basically saying "why bother breeding we have landraces?"

i m just trying to figure this out

it seems like you are saying TH assumes he can predict the outcome when i get the impression he is saying one should test for outcomes before making presumptions that a particular pair of selections will have the desired outcome

am i confused here?

 

[Tom Hill]

Hey again Nunsacred,

While I get your point regarding the various complexities of inheritance and expression, breeders (by utilizing science/maths) do indeed measure and predict trait inheritance and penetrance etc by such means as the aforementioned top cross procedure. When genotype (V) tests much better against genotypes (L,M,N,O,P, and Q), than genotype (Z) does, then we have simplified, and can quite confidently assign a higher genotypic value to genotype (V), than (Z). Rendering the complexity of inheritance a rather moot point.

As to the testing of candidates by way of selfing to determine their levels of homozygosity. Professional breeders of outcrossing species don't even go to to where I think you're talking about, that is testing plants not proven to be homozygous against anything else (except for the aforementioned heterozygous top cross parent). In arguing otherwise you are arguing against what the pros do, and what they do is based on science, not lip gloss, I assure you.

Very few here take advantage of any damn thing that we know about the science of plant breeding as they go hacking around and attempting to come up with arguments supporting their "methods". But the measuring of homozygosity among their candidates before proceeding is a relatively easy thing they can do, to greatly improve their efforts.

When you say "Testing self crosses, there's some logic to it, I agree it's better than nothing, it's a good practice, even, but it's not always better than trying other plants instead"... Again, you are attempting to separate swinging the bat from hitting the ball,, you want to go straight to hitting the ball or argue which is better or sometimes better etc. The pros do both, one before the other, not one or the other. They do not even fathom of testing out to other plants before homozygosity has been accomplished/located. They look on that as, "a bit rich" -that is- thinking they were going to hit the ball with any consistency without first swinging the damn bat. -T

 

[Tom Hill]

It seems to me that he is attempting to argue that the usual goal of breeders of outcrossing plants to "develop numerous highly homozygous lines (individuals/candidates) -the pros fucking starting point mind you!- is not firmly backed by the maths and science of plant breeding. It seems he wants to find some justification to just go straight to "testing specific combinations of pairs of lines to identify the very few pairs that have the potential to produce truly excellent single-cross hybrids" just like pretty much every hack in this thread wants to do and has been doing all along. I am here to say fuck all that, it's a really shitty bet folks -comparatively.

 

[Madjag]

An interesting quick synopsis of Norman Deno's 1993 book, Seed Germination Theory and Practice.

Thanks to "The Seed Site"
http://theseedsite.co.uk/normdeno.html​

"The first edition of Norman Deno's book was written in 1993, and detailed his conclusions on seed germination, and more particularly his findings on the types of inhibitors preventing seeds from germinating, and ways of overcoming these inhibitors, based on experiments with seeds of over 2500 species, in 805 genera, from 145 plant families.

Norman Deno was Professor Emeritus of Chemistry at Penn State University, and during his career in Chemistry published 150 papers, with another twenty papers during his secondary career in horticulture.

The following is a brief synopsis of the second edition of the book. There are also several Supplements, covering experiments on thousands more species.

Chapter 1 - Introduction and Principles

Chapter 2 - Germination, Definition and Description

Chapter 3 - Design of the Experiments

An explanation of the way the experiments were carried out, how the results were recorded and interpreted, with a brief explanation of the main variables which were examined: Temperature, Time, Dry Storage, Light, Oscillating Temperatures, and Gibberellins. The temperatures of 40oF and 70oF were chosen for the experiments as they represent the average winter or summer temperatures. Cycles of three months at these temperatures were used to simulate seasons.

Chapter 4 - Rates of Germination

A detailed account of how the results of the experiments were recorded, and what they mean.

Chapter 5 - Inhibitor Destruction by Dry Storage

Experiments showed that seeds of 50% of temperate zone plants can be collected, put in an envelope and left on a shelf, and will germinate when sown several months later. Professor Deno contends that the dry storage is an essential part of the germination process, and that chemical inhibitors present in the seeds are being destroyed during storage. Many members of the Asteraceae (Daisy), Brassicaceae (Mustard), Campanulaceae (Bellflower) and Poaceae (Grass) Families, including most garden annuals and vegetables, are in this group.

Chapter 6 - Inhibitor Destruction by Moist Conditions

In many species, the germination inhibitors are destroyed by exposure to moisture. There is an induction period before germination begins, and after this period, there is a sudden onset of germination. This pattern has long been recognised but not understood. It is what is happening when seeds are sown in the autumn or winter and germinate in the spring. The induction period has previously been referred to as a period of stratification or 'dormancy', but is in fact the time when the seed is at its most active, destroying chemical germination inhibitors. In some cases, the germination inhibitor is destroyed at 40oF, and germination also occurs at 40oF. This pattern is found in many bulbous species. A related mechanism is when the inhibition system is destroyed at 70oF.

Chapter 7 - Two or More Inhibiting Systems

Many examples were found where there were two or more sets of inhibiting systems, each requiring different conditions for destruction.

Chapter 8 - Seeds Embedded in Fruits

It was found that in many fruits there is an inhibitor in the fruit which prevents the seeds germinating. These seeds need to be washed to remove the chemical inhibitor.

Chapter 9 - Physical Mechanisms for Inhibiting Germination

Seeds of many legumes and others have impervious seedcoats, and these seeds will germinate if a hole is made in the seedcoat. Soaking seeds in hot water will also produce the same effect, because the heat causes the expansion of the seed coat and opens microfissures. Professor Deno says that the belief that freezing and thawing has the same effect is a myth, as true freezing and formation of ice crystals in the seed would be fatal. But oscillation in temperatures opens microfissures.

Chapter 10 - Outdoor Exposure and Oscillating Temperatures

A time honoured procedure has been to sow seeds in pots and place them outdoors in the fall. Germination often takes place in the spring. This procedure provides the low temperatures at which some species germinate and the low temperatures where some inhibitor systems are destroyed. The experiments showed that some species gave good germination when placed outdoors whereas germination was low or none in all other treatments. Further research showed that some seeds require oscillating temperatures to stimulate germination.

Chapter 11 - Photoeffects

The responses to light were complex. The results of experiments showed that seed behaviour fell into seven categories: (1) seeds which germinated only in light at 70oF; (2) seeds which required light and a pre-treatment; (3) seeds where germination was blocked by light; (4) seeds which required light for germination of fresh seed at 70oF but pretreatments removed the photorequirement; (5) seeds that required light for germination at 70oF but also germinated in the dark at 40oF; (6) seeds that germinated in either light at 70oF or in outdoor conditions; (7) seeds whose germination is promoted by light, but some germination occurs in the dark.

Chapter 12 - Exogenous Chemical Effects and the Stimulation of Germination by Gibberellins

Detailed descriptions of methods of using chemicals, particularly Gibberellins, to stimulate germination. Professor Deno contends that gibberellins are natural stimulators of germination in certain species and that the evolution of this requirement is critical to the survival of those species. In the chapter on how the experiments were conducted, details are given of the amount of gibberellic acid found to be effective.

Chapter 13 - Dry Storage and Longevity of Seeds

Ultimately, dry storage is fatal to all seeds. The length of time seeds can be stored and still remain viable depends on temperature and relative humidity. Seeds with impervious seedcoats remain viable for the longest periods. A few species have seeds that retain viability for only a few days, most species remain viable for 1-2 years, some 10-50 years, and some Fabaceae can remain viable in dry storage for 100-150 years.

Chapter 14 - Growing Plants from Seeds

Chapter 15 - Collection of Seeds

Chapter 16 - Plant Nomenclature

Chapter 17 - Endangered Species and Conservation

Chapter 18 - List of Genera Studied Arranged by their Plant Families

Chapter 19 - Rate Theory in More Detail

Chapter 20 - Summary of Data Arranged by Genera

Effectively, a Seed Germination Database for over 2500 species, based on the results of the experiments.

Chapter 21 - The Orchids

Chapter 22 - The Grasses

Chapter 23 - List of Donors of Seeds

Chapter 24 - List of References


Seed Germination Theory and Practice was published privately by Professor Deno. He has now retired (at the age of 89!), so the book and supplements can not now be obtained direct from him. Copies may be available from specialist societies or second-hand bookshops.

The Second Edition of Seed Germination Theory and Practice, published in 1993, is now online, and can be read and downloaded in PDF format from the USDA website. The First Supplement, published in 1996, is here, and the Second Supplement (published in 1998) is here.

 

[Tom Hill]

It seems to me that he is attempting to argue that the usual goal of breeders of outcrossing plants to "develop numerous highly homozygous lines (individuals/candidates) -the pros fucking starting point mind you!- is not firmly backed by the maths and science of plant breeding.

Which is odd to me, since I know the gentleman to be one that often has keen insight and thoughts of value. Perhaps I am misunderstanding his thought here, and perhaps he would care to elaborate.

I am aware of many selection methods which utilize "trying other plants instead", but they all have the same goal, and that is attaining wanted traits in a homozygous condition be it half-sib or full sib family selection etc etc. If that is not obtained, then that particular family is culled routinely and that is par for the course.

At any rate, please do elaborate, because it seems to me you are stating that the very foundations of plant breeding are unscientific, and that elicits a gag reflex from yours truly.

 

[Nunsacred]

That's right, the principle of breeding for homozygosity is profane.
Statistically you will wreck more traits than you can enrich.
This is where the illusion of hybrid vigour comes from, the temporary respite in F1
From ruinous bottlenecked inbreds with stress from badly configured chromatin.

If you select your traits from a reasonably open breeding program instead, the robustness of your background fitness isn't threatened nearly so badly. You gain so much more medium term efficiency than in the short term efficiency/crash scenario of chasing uniformity.

I do think land races are a lot closer to "ideal" than intensively bred lines.
It does come down to that.
The value of saying "this bunch of seed should give a decent result overall whatever the environment" rather than "this a highly strung pedigree can be 11% better yield when you rush around like Laurel & Hardy making sure it's pampered to exacting needs".....

If I'm so outrageously wrong then you can surely laugh it off
Call me deluded
Claim my luck will run out or I wil be converted on the Damascene road when I pop some S5 blockchunkbabaBoomKush.

 

[offthehook]

I can follow your thoughts very well Nunsacred.

That's why I also use open breeding programs that are diverted over several lines.

But then again, If I 'd ever like my auto strain to become more potent for some reason, I know now where to go and obtain these killer homozygotes to start my own super vigorous & resistend strain all over from scratch again.

credence to TH.

I think of it as a good thing to have an option beeing able to combine old with new.

And it is my hippy mentality telling me to have respect for the characters of both as well old, as new school, and as such incorporate what is respecteble into my own ambitions.

 

[Jbomber79]

Nans if nothing else this thread has got me to scientifically critique my work more, cheers Tom!

 

[Tom Hill]

Yes Nunsacred, that is to be laughed off. There is a time for preservation, and there is a time for going for the throat with more intensive breeding methods - stop trying to blend the two together, it is wasted effort/time. The methods you poddy-mouth are responsible for damn near every breeding advancement over the past century! You are like the guy arguing from his limited experience of selfing one family to death, without the key insight of realizing it doesn't always turn out that way. The same effort you put into slowly going nowhere, should be instead focused on speeding down the highways in many different directions. Same number of plants, your methods lose, and this is well known and taken advantage of by plant breeders today, wise up. Combining several varying but homozygous genotypes all giving rise to similar phenotypes creates a line every bit as fit and adaptive as any of these decrepit wheel spinning methods you speak of, and yes you are deluded to not understand this fact.

 

[Ur Humbl Nr8tor]

I wonder what you all think of this...

DJ Short F-13. Started male and went to throwing calyx and pistils right before pollen sacks opened.

Tom, is this the hyper hermaphrodite you've mentioned in the past.

What's the value in future breeding, because it's tossing mad pollen at some plants right now.

 

[CHillTowneGenes]

wow... ummm?? never seen that before. thas some freaky shit Ur Humbl Nr8tor, I would like to know what comes out of that...

 

[Tom Hill]

Who's Ton and what is a hyper hermaphrodite? tehee.

I will bet that the plant is XX, and rich in male modifying autosomal factors. Further that you'll see a vast swing towards the female phenotype in the following generation. Whether or not that generation will be plagued with the same phenomenon we see here, will be determined by the homozygosity/heterozygosity/prepotency of those autosomal regions, and their ability to pass that trait onto the next generation. In my (and Dj's, and Charlies, and many others') experience, the trait is complex enough to bet against that from happening the majority of the time. There is one way to find out.

 

[offthehook]

I had a White russian male that turned out like yours and had pollinated a variety of different strains.
Tom is right on that you can expect a large majority of females to come out from the f1
There was also a percentage of about 10 to 15 % 'early herma's. The ones that show first females and later on male flowers.
However, I call them 'early' herma's, because they will show this tendency right in the beginning of bloom. Not anymore later on.
No more of the same 'males turning into females' were to expect from my f1 batch.

 

[GeorgeWBush]

well I'll be polite this time seeing as the language of the land has evolved into a much more polite manner.Tom, your mind is great it's your vision that needs adjusting.You're suffering a little from tunnel vision.personally I believe it's just good ole fashioned stubbornness that prevents you from accepting the notion that perhaps there is less science involved in seed breeding than you're comfortable with.That is not to say there is no place for a mind such as yours,there certainly is as well as your methods but nature has her own way of expressing herself that science and math will never be able to calculate which is what I believe Nun was saying and I tried to say and how many countless others have tried to say. And you can tweek and tinker with homozygosity all you want trying to create something new and improved and it wont change the fact that somewhere along the line nature is going to takes it's course and throw a monkey wrench in the works, a single recessive undesirable trait forgotten about for generations and assumed breed out will one day decide to dominate the offspring knocking you back to square one. what are you going to say about breeding for homozygosity then ?

 

[Tom Hill]

George, fuck all that. What is happening here is this. You are most all of you, in this online cannabis world, so fucking delusional and behind reality that there really is no words for it. And when you come in contact with the truth, it is so fucking alien to you that you do not have any idea of how to react. So you reach, grab, and try to find any godamn thread of what was your previous reality like some child hanging onto his lil woobie/blanket. I really see this as entertainment mostly, along the lines of your masters degree.

 

[gloryoskie]

Awesome thread, here's one for fun.

 

[GeorgeWBush]

Tom you suffer from delusions of grandeur,there is no talking to you.You display classic bi-polar personality traits perhaps borderline schizophrenia although I assume the different sides of your personality are actually quite similar which is not all that uncommon for someone with hyper cerebral activity such as yourself so it's more a few different versions of the same person as opposed to two individual polar opposite personality's you would see in advanced schizophrenia and early stages of dementia.I'd say there are meds for it but they treat the symptom not the disease.Your views on breeding bring to light similarities between you and a famous German politician from the WW2 era in a strictly clinical sense only he was trying to achieve a much more ambitious goal, a despicable, homicidal idea,but a ambitious goal.You get the point I'm sure. if not I'll put it poetically. The beauty in this world is found in the unknown.It is the imperfections that add all the character.I hope this one was of great amusement for you.

 

[Tom Hill]

Tom you suffer from delusions of grandeur,there is no talking to you.You display classic bi-polar personality traits perhaps borderline schizophrenia although I assume the different sides of your personality are actually quite similar which is not all that uncommon for someone with hyper cerebral activity such as yourself so it's more a few different versions of the same person as opposed to two individual polar opposite personality's you would see in advanced schizophrenia and early stages of dementia.I'd say there are meds for it but they treat the symptom not the disease.Your views on breeding bring to light similarities between you and a famous German politician from the WW2 era in a strictly clinical sense only he was trying to achieve a much more ambitious goal, a despicable, homicidal idea,but a ambitious goal.You get the point I'm sure. if not I'll put it poetically. The beauty in this world is found in the unknown.It is the imperfections that add all the character.I hope this one was of great amusement for you.

What you are witnessing you absolute moron, is me experimenting with various doses of different drugs to ascertain just how much of a handicap I must give you, before we can have meaningful communications lol. You're never going to pay off that student loan with such wildly incorrect hypotheses

 

[Tom Hill]

Yeah Mapinguari, I take cannabis fairly seriously.