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Sire Lines & "Y" They Matter

acespicoli

Well-known member

Evolution of the dominant diploid phase​

It has been proposed that the basis for the emergence of the diploid phase of the life cycle (sporophyte) as the dominant phase (e.g. as in vascular plants) is that diploidy allows masking of the expression of deleterious mutations through genetic complementation.[30][31] Thus if one of the parental genomes in the diploid cells contained mutations leading to defects in one or more gene products, these deficiencies could be compensated for by the other parental genome (which nevertheless may have its own defects in other genes). As the diploid phase was becoming predominant, the masking effect likely allowed genome size, and hence information content, to increase without the constraint of having to improve accuracy of DNA replication. The opportunity to increase information content at low cost was advantageous because it permitted new adaptations to be encoded. This view has been challenged, with evidence showing that selection is no more effective in the haploid than in the diploid phases of the lifecycle of mosses and angiosperms.[32]

  • Angiosperm life cycle
    Angiosperm life cycle
  • Tip of tulip stamen showing pollen (microgametophytes)
    Tip of tulip stamen showing pollen (microgametophytes)
  • Plant ovules (megagametophytes): gymnosperm ovule on left, angiosperm ovule (inside ovary) on right
    Plant ovules (megagametophytes): gymnosperm ovule on left, angiosperm ovule (inside ovary) on right
  • Double fertilization
    Double fertilization
 

acespicoli

Well-known member

Evolution of uni- and bifactorial sexual compatibility systems in fungi​

Heredity volume 111, pages445–455 (2013)
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1731419457651.png

 
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dogzter

Drapetomaniac
You cannot escape the male side of things.
You can water it down immensely by selfing,femming but all your doing is watering down the last male used......
 

acespicoli

Well-known member
:yeahthats

The wave of gene advance under diverse systems of mating​

Heredity volume 125, pages253–268 (2020)

I looked for White Widow,
***
"Ingemar (De Sjamaan) invented WW already in 1987. [...]
It was called Arnhem’s Wonder and already won the first HL cup in 1989. [...]
For those who don’t believe this, please call Coffeeshop Catweazel or Roger from the grow shop; they worked with Ingmar for a long time.
Roger has always sold the clones he had. He had a famous grow shop in Nijmegen.

I bought the male and female among other plants in 1992 and only crossed them in 1994.

I did not have to do any breading on the White Widow at that time because Ingemar had already done it for us.And to this day you can still buy original clones of the White Widow in that area of Holland."
Arjan (Green House Seeds)
***

In the regular IBL line run in 2024 im only finding...... Manga Rosa
Get the clone if you can find it from '87

thx @dogzter if you had made that statement as a #1 first thread starter post,
a short read this would have been ;)
Best >>> :huggg:


Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation.[3]
It can also cause initially rare alleles to become much more frequent and even fixed.

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acespicoli

Well-known member


 
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acespicoli

Well-known member

Production of F1 hybrids​

In plants​

Crossing two genetically different plants produces a hybrid seed. This can happen naturally, and includes hybrids between species (for example, peppermint is a sterile F1 hybrid of watermint and spearmint). In agronomy, the term F1 hybrid is usually reserved for agricultural cultivars derived from two-parent cultivars. These F1 hybrids are usually created by means of controlled pollination, sometimes by hand pollination. For annual plants such as tomato and maize, F1 hybrids must be produced each season.

For mass production of F1 hybrids with uniform phenotype, the parent plants must have predictable genetic effects on the offspring. Inbreeding and selection for uniformity for multiple generations ensures that the parent lines are almost homozygous. The divergence between the (two) parent lines promotes improved growth and yield characteristics in offspring through the phenomenon of heterosis ("hybrid vigour" or "combining ability").

Two populations of breeding stock with desired characteristics are subjected to inbreeding until the homozygosity of the population exceeds a certain level, usually 90% or more. Typically, this requires more than 10 generations. Thereafter, the two strains must be crossed, while avoiding self-fertilization. Normally, this is done with plants by deactivating or removing male flowers from one population, taking advantage of time differences between male and female flowering, or hand pollinating.[4]

In 1960, 99% of all corn, 95% of sugar beet, 80% of spinach, 80% of sunflowers, 62% of broccoli, and 60% of onions planted in the United States were F1 hybrids.[citation needed] Beans and peas are not commercially hybridized because they are automatic pollinators, and hand pollination is prohibitively expensive.

F2 hybrids​

F2 hybrids, the result of self or cross-pollination of F1s, lack the consistency of F1s, though they may retain some desirable traits and can be produced more cheaply because hand pollination or other interventions are not required. Some seed companies offer F2 seed at less cost, particularly in bedding plants, where consistency is less critical.[5]


But seed collected from an Fl hybrid will not produce plants the same as those from which it is collected. Only by crossing the pure lines can the variety be made - and only the original breeder has the necessary pure lines.
 
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acespicoli

Well-known member

Genetic complementation, heterosis,​

and the evolution of sexual reproduction​

Heterosis is the tendency for hybrid individuals to exceed their purebred parents in size and vigor. The phenomenon has long been known in animals and plants. Heterosis appears to be largely due to genetic complementation, that is the masking of deleterious recessive alleles in hybrid individuals.

In general, the two fundamental aspects of sexual reproduction in eukaryotes are meiosis and outcrossing. These two aspects have been proposed to have two natural selective advantages, respectively. Meiosis is proposed to be adaptive because it facilitates recombinational repair of DNA damages that are otherwise difficult to repair. Outcrossing is proposed to be adaptive because it facilitates complementation, that is the masking of deleterious recessive alleles [5] (also see heterosis). The benefit of masking deleterious alleles has been proposed to be a major factor in the maintenance of sexual reproduction among eukaryotes. Further, the selective advantage of complementation that arises from outcrossing may largely account for the general avoidance of inbreeding in nature (e.g. see articles kin recognition, inbreeding depression, and incest taboo).[6]
 

acespicoli

Well-known member

Recombination inhibition​

Most chromosomes recombine during meiosis. However, in males, the X and Y pair in a shared region known as the pseudoautosomal region (PAR).[21] The PAR undergoes frequent recombination between the X and Y chromosomes,[21] but recombination is suppressed in other regions of the Y chromosome.[14] These regions contain sex-determining and other male-specific genes.[22] Without this suppression, these genes could be lost from the Y chromosome from recombination and cause issues such as infertility.[23]

The lack of recombination across the majority of the Y chromosome makes it a useful tool
 
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acespicoli

Well-known member
Degeneration may simply be the fate of all non-recombining sex chromosomes, due to three common evolutionary forces: high mutation rate, inefficient selection, and genetic drift.[14]

:thinking: Degeneration - IN GENETICS, a recklessly used term, along with "junk" DNA....

Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ultimate source of all genetic variation, providing the raw material on which evolutionary forces such as natural selection can act.
 

acespicoli

Well-known member
Subclade A1_THCAS comprises full-length coding sequences from THCA-producing plants such “Purple Kush,” “Skunk#1,” and “Chemdog91,” including functionally characterized THCAS (Sirikantaramas et al. 2004), “drug-type THCAS” sequences (Kojoma et al. 2006), “active THCAS” sequences (McKernan et al. 2015), and fully functional (BT) as well as nearly defective (BT0) coding sequences (Onofri et al. 2015) (fig. 3, supplementary figs. S1 and S2, Supplementary Material online; table 1 and supplementary table S5, Supplementary Material online).

Plants (Basel)
. 2019 Nov 12;8(11):496. doi: 10.3390/plants8110496

Highly Predictive Genetic Markers Distinguish Drug-Type​

from Fiber-Type Cannabis sativa L​

 
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