Repoductive Systems & Breeding Plans - "Biological Foundations of Plant Breeding"

[xmobotx]

when i say "agree" i mean maybe not so much "shun fools" but get the damn fools up to speed

you are right mr californicus ~theres probably a storm coming and a bunch of discombobulated stoners may find themselves a few years down the road w/ their pants around their ankles

corpo's may be communication nightmares but they have that money-making bug and just might be working on this w/ crack teams ~could be pretty tough to compete from the "is this as good as mj gets?" side of the fence

 

[Infinitesimal]

Please don't get the dictionary thread locked! What we really need is a calculus thread somewhere...

or how about statistics?


lets list all sets of real numbers for each scale of infinity... can't wait to read the end of that thread!

aleph null

 

[TomCalifornicus]

Probability/statistics are all that is required, all else is for fun.

 

[xmobotx]

fuck yeah!

statistics

 

[Aardwolf]

Subjective Probability

Subjective Probability

Subjective probability - Individual personal judgement about how likely a particular event is to occur. It is not based on a precise computation but is often a reasonable assessment by a knowledgeable person.

Like all probabilities, a subjective probability is conventionally expressed on a scale from 0 to 1; a rare event has a subjective probability close to 0, a very common event has a subjective probability close to 1.

A person's subjective probability of an event describes his/her degree of belief in the event.

 

[Aardwolf]

Modelling and Simulation of Plant Breeding Strategies

Modelling and Simulation of Plant Breeding Strategies

Jiankang Wang Institute of Crop Science and CIMMYT China, Chinese Academy of Agricultural Sciences (CAAS), China.

From the 1980s onwards, all crosses onto selected F1 generations were single cross, backcrosses or top crosses (van Ginkel et al., 2002). Single and top (or three-way) crosses are commonly used among adapted parental lines, while backcrosses are preferred for transferring a few useful genes from donor parents to adapted lines. The single backcrossing approach (one backcross to the adapted parent) was initially aimed at incorporating resistance to rust diseases based on multiple additive genes (Singh and Huerta-Espino, 2004). However, it soon became apparent that the single backcross approach also favoured selection of genotypes with higher yield potential.

The reason why single backcrossing shifts the progeny mean toward the higher side is that it favours the retention of most of the desired major additive genes from the recurrent, while simultaneously allowing the incorporation and selection of additional useful small-effect genes from the donor parents.

The breeding efficiency of this strategy compared with other crossing and selection strategies was investigated through computer simulation for many scenarios, such as the number of genes to be transferred, frequency of favourable alleles in donor and recurrent parents etc.

Results indicated this breeding strategy has advantages in retaining or overtaking the adaptation of the recurrent parents and at the same time transferring most of the desired donor genes for a wide range of scenarios (Wang et al., 2009).

Two times of backcrossing has advantages when the adaptation of donor parents is much lower than that of the adapted parents, and the advantage of three times of backcrossing over two times of backcrossing is minimal.

The recommend use of the single backcrossing breeding strategy is based on three assumptions:
(1) Multiple genes govern the phenotypic traits to be transferred from donor parents to adapted parents,
(2) Donor parents still have some favourable genes that may contribute to the improvement of adaptation in the recipient parents even under low adaptation,
(3) The conventional phenotypic selection is applied or the individual genotypes cannot be precisely identified.

 

[Aardwolf]

Section 2.2.4 Design breeding with known gene information.

Section 2.2.4 Design breeding with known gene information.

This section is an interesting read, it shows how breeding has developed much over the last decade.

Topcross 1 combined with Scheme 2 resulted in the least DNA samples per selected line, and therefore was the best crossing and selection scheme. This selection being the fastest cheapest and cost effective and conservative on room space.

 

[stickshift]

Jiankang Wang Institute of Crop Science and CIMMYT China, Chinese Academy of Agricultural Sciences (CAAS), China.

From the 1980s onwards, all crosses onto selected F1 generations were single cross, backcrosses or top crosses (van Ginkel et al., 2002). Single and top (or three-way) crosses are commonly used among adapted parental lines, while backcrosses are preferred for transferring a few useful genes from donor parents to adapted lines. The single backcrossing approach (one backcross to the adapted parent) was initially aimed at incorporating resistance to rust diseases based on multiple additive genes (Singh and Huerta-Espino, 2004). However, it soon became apparent that the single backcross approach also favoured selection of genotypes with higher yield potential.

The reason why single backcrossing shifts the progeny mean toward the higher side is that it favours the retention of most of the desired major additive genes from the recurrent, while simultaneously allowing the incorporation and selection of additional useful small-effect genes from the donor parents.

The breeding efficiency of this strategy compared with other crossing and selection strategies was investigated through computer simulation for many scenarios, such as the number of genes to be transferred, frequency of favourable alleles in donor and recurrent parents etc.

Results indicated this breeding strategy has advantages in retaining or overtaking the adaptation of the recurrent parents and at the same time transferring most of the desired donor genes for a wide range of scenarios (Wang et al., 2009).

Two times of backcrossing has advantages when the adaptation of donor parents is much lower than that of the adapted parents, and the advantage of three times of backcrossing over two times of backcrossing is minimal.

The recommend use of the single backcrossing breeding strategy is based on three assumptions:
(1) Multiple genes govern the phenotypic traits to be transferred from donor parents to adapted parents,
(2) Donor parents still have some favourable genes that may contribute to the improvement of adaptation in the recipient parents even under low adaptation,
(3) The conventional phenotypic selection is applied or the individual genotypes cannot be precisely identified.

View Image

for a further read on that, see here..

http://www.isbreeding.net/oldweb/Publications.pdf/english22.pdf

it's all based on his Qu hybrid computer simulation. you can download that at various places and it's applicable to wheat/maize breeding... if you are incorporating a single gene trait it would be very useful!. A few years ago there were a few of us in a thread going through a lot of Wangs stuff, it's all on this site already... sadly the fact that some deem some threads more useful than others and can't see where good info should be retained.

here's a C & P from the paper.

Backcrossing in plant breeding
Backcrossing is commonly used in plant breeding. In most
cases, backcross breeding means that one or a few genes
are transferred from a donor parent to an adapted line(Allard 1960
; Stoskopf et al.1993). Assuming DT can be precisely phenotyped, repeated backcrossing can efficiently recover the recurrent parent (Allard 1960). However, single-gene inherited traits are rare in breeding, as is a donor parent with only one or two useful genes. When the number of genes to be transferred from the donor parents to adapted parents is relatively high (e.g., 5–10), it is less likely that all of the donor parents’ favorable genes can be transferred to the adapted parents without reducing the adaptation of the recurrent parents in one breeding cycle.

So useful if one is trying to incorporate a single gene ie resistance to something not so useful if you are trying to replicate a clone etc.


you used to be able to get the likes of Qu gene, Qu hybrid etc here, there are plenty of other models out there too.

http://www.uq.edu.au/lcafs/index.html?page=59974
https://www.integratedbreeding.net/supplementary-toolbox/qu-gene

Just bare in mind it was all developed specifically for wheat breeders and that they typically find the plants of interest to be the recurrent at around the F7 stage.

 

[Aardwolf]

Welcome back stickshift, This thread is the Scientific Reference Bibliography https://www.icmag.com/ic/showthread.php?t=49069desitific


This one CANNABIS REFERENCES For Breeding https://www.icmag.com/ic/showthread.php?t=49499
This second thread was started by the Skunkman, here is the link from the thread in the above link.

 

[stickshift]

Welcome back stickshift, This thread is the Scientific Reference Bibliography https://www.icmag.com/ic/showthread.php?t=49069desitific


This one CANNABIS REFERENCES for breeding https://www.icmag.com/ic/showthread.php?t=49499 This thread started by the Skunkman is a link from the thread in the above link.

And?

 

[Tom Hill]

Thank you Kopite/stickshift, long have you been a voice of reason in the midst of absolute confusion, clearly sir http://www.youtube.com/watch?v=UWmequyLgws biglove brother.

 

[CrazyKoala]

Hey Aardwolf, what do you want to say with your copy and pasting without references?

I'm asking because you're being a provocateur. Rather than esoteric wordy psycho-babble, can you concisely tell me what you're trying to get at? Lay approximations are fine, we can start there, because with your incorrect usage of precise terms, the experts aren't understanding what you're trying to say, and that's not because of their lack of mental acuity.

What are we trying to propose or do please? I say this genuinely and constructively. Concision and original paraphrasing may go further than your long-winded, unfocused string of plagiarized quotes.

 

[CrazyKoala]

Well I guess after you got called on BS, you had to post more science literature to save face. Maybe this thread needs to be closed...

 

[bh4vn35h]

LOL

 

[Aardwolf]

Its been a while since I updated this thread, I will have a proper read through where I was and shall continue where I left off in due course.

 

[WelderDan]

I will suggest now that anyone who is not familiar with the terminology in this thread to pick up a book or google the word/phrase and learn.

This is not your thread to post your comments in, it is a thread to read and learn from.

This was from your 6th post.

Read and learn from this: No one wants to be talked down to, let alone someone that merely uses cut and paste to sound smart.

If something is over my head, I'll ask Tom, or Skunkman, or numerous others that have the chops to back it up.

Someone shut this thread down

 

[PaullyHighBred]

...........................

 

[RonSmooth]

Aardwolf,

Is English your fist language? I am genuinely curious.

 

[Tonygreen]

Its been a while since I updated this thread, I will have a proper read through where I was and shall continue where I left off in due course.

What do you plan to copy and paste next mate?

 

[Sam_Skunkman]

When posters here get all high and mighty and speak down to the majority of posters my first question is wheres the beef? I mean what good is an understanding of genetics if it accomplishes little or nothing? Please Aardwolf just let us have an opportunity to try your work that is the result of superior understanding of breeding and breeding techniques.
Then all the doubters can try them and maybe start singing your praise?
Talk is pretty cheap, wheres the proof? How many years have you grown & bred Cannabis?
I will grow what you consider your best work, be it seeds or clones, and I will report what I find. If it is great I will say so, if it sucks I will say so, and why in either case...
I hope it is not another WLD/NLD poly-hybrid made from combining others work?
But I will try it, be it just a simple hybrid of female clones that others bred and you selected to combine or real involved breeding work that took several years to do and is all your work.
I am interested....

-SamS