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:D Genetic Preservation :D - Breeding

acespicoli

Well-known member

‘A classification of endangered high-THC cannabis
(Cannabis sativa subsp. indica) domesticates and their wild relatives’

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Type specimen for Cannabis sativa subsp. indica var. asperrima (1924)

Legacy​

The Leningrad seedbank was preserved and protected through the 28-month long Siege of Leningrad. While the Soviets had ordered the evacuation of art from the Hermitage Museum, they had not evacuated the 250,000 samples of seeds, roots, and fruits stored in what was then the world's largest seedbank. A group of scientists at the Vavilov Institute boxed up a cross section of seeds, moved them to the basement, and took shifts protecting them. Those guarding the seedbank refused to eat its contents, even though by the end of the siege in the spring of 1944, a number of them had died of starvation.

When I was a younger man many of the cannabis strains were from bag seed we grew the seed from import
As a collector you think in the beginning it would be nice to have a few strains from a seedbank circa 80-90s
The seedbanks had a origin for most of their strains based on the most popular imports
Since 2000 some of the strain names you would not even be able to follow the lines of origin
Im starting to realize the value of saving diversity as the genetics have become extremely bottle necked
More so than the idea of just indica /sativa, what would you need to have to call it a complete collection.


var. indica = domesticated aka landrace (‘Sativas’)
var. afghanica = domesticated aka landrace (‘Indicas’)
var. asperrima = wild-type
var. himalayensis = wild-type
var. spontanea


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Photo: RS Angus

Nanda Devi​

Genetics: Traditional Himalayan Domesticate (Intermediate “Landrace”)
Sourcing: The Real Seed Company, Kumaon Himalaya, 2021 Harvest
Purpose: Charas (hand-rubbed resin)
Latitude: 29° N
Harvest: Mid-August to mid-September
Height: 2 – 5 metres outdoors
Aroma: Floral, tangy, spicy, herbal
Characteristics: Early maturing, soaring high, hardy, humidity tolerant
Classification: C. sativa subsp. indica var. himalayensis
Grow Type: Greenhouse or outdoors
A charming rustic Himalayan hashplant, this is a specialised charas domesticate unique to a few remote villages of northern Kumaon to the east of the Nanda Devi Sanctuary. Unlike typical multipurpose Himalayan crops, this strain is not grown for fibre or seed but instead is used by farmers exclusively for charas. The resin has an intense, soaring high that evens out into a long-lasting buzz.


Unusually fast-flowering for a Himalayan strain, ‘Nanda Devi’ is harvested from mid-August to mid-September during breaks in monsoon rains. Buds are highly resinous and aromatic, producing charas that has a better, stronger high than the distinct large-seeded domesticate (known as ‘dati’) which local villages also cultivate. All Himalayan domesticates occur as components of crop–weed complexes. However, wild-type var. himalayensis traits appear to be more pronounced in this accession than in multipurpose types.


Aromas are floral, tangy, herbal, and spicy. The traditional rustic braided charas this domesticate produces is somewhat harder and coarser than the typical Parvati type, but it has a very distinctive euphoric effect—an uplifting and positive vibe that makes it special.


Fans of Himalayan charas such as the Nepalese of the sixties and seventies will enjoy these plants. Highly recommended for those wanting a pristine, traditional Himalayan charas strain.


Terpene and cannabinoid profile for a standout specimen grown outdoors in Spain:


THC: 10.87%
CBD: 1.05%
CBN: 0.08%
Beta-caryophyllene: 0.42mg/mL
Alpha-pinene: 0.15mg/mL
Beta-pinene: 0.17mg/mL
Myrcene: 0.17mg/mL
Limonene: 0.07mg/mL
Geraniol: 1.56mg/mL
Terpenolene: 0.15mg/mL
Humulene: 1.27mg/mL
Nerolidol-1: 0.23mg/mL


This was a second run. The initial scan showed a higher THC content.


NOTE: An experienced horticultualist running a licensed grow achieved c. 80% germination rates with past accessions just by keeping it simple.


Another cultivator with extensive experience of this accession also writes as follows: “Usually around 25% sprout very quick and healthy. Around a half should take to 4 weeks sometimes a bit more to go on their way with a delayed germ rate depending on the conditions and the care of the farmer. The fourth quarter is unpredictable depending on conditions.”


A report of Nanda Devi seedlings emerging one year after an outdoor grow confirms the strong wild-type component to this strain. Please see the following post on germinating wild-type seed. Don’t throw away seeds that haven’t emerged. They’re most likely dormant.
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Photo: RS Angus

Kurgan​

Genetics: Wild-type Urals Cannabis
Sourcing: Russian Landrace Bureau, Kurgan Oblast, Southern Urals, Russia, 2019
Purpose: n/a
Latitude: 54° N
Harvest: Mid to late August
Height: 1.5 – 4 metres outdoors
Aroma: Lavender
Characteristics: Early maturing to autoflowering; CBD
Classification: C. sativa ssp. sativa var. spontanea
Grow Type: Outdoors, greenhouse

These seeds were hand-picked from day-neutral (‘autoflowering’) wild-type stands in the southern Urals, Russia. The collectors selected plants for their strong and sweet aromas, most notably a marked lavender scent. In the vernacular taxonomy, this type of Cannabis is known as Ruderalis.

According to the collectors, these plants did not have a psychoactive effect beyond being very slightly ‘stoney’. The southern Urals are not known to have a history of cultivating Cannabis for use as an ‘intoxicant’. In other words, these populations could be classified in the Small and Cronquist taxonomy as subsp. sativa var. spontanea, i.e. ruderal hemp. The predominant cannabinoid is likely CBD.

On the spectrum from domesticated to “wild”, these Urals populations appear to be very weedy. For breeders and collectors, their value is in their biodiversity, hardiness, and early finishing time.


var. asperrima = wild-type ... to be continued
 
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aliceklar

Active member
Great info! Thanks @acespicoli .

I've used the seedfinder site before when I've been planning crosses to get some idea of the heritage of different strains (either to attempt to concentrate desired characteristics common to both, or to ensure as wide a cross as possible). its a great resource.
 

acespicoli

Well-known member
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Table 1. Sample information and summary of haplotype distribution, genetic diversity for each population based on the combined five cpDNA regions.

Interesting is the latitude range of plants
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environmental phenotype by latitude ?
How long does it take for a landrace to no longer be a landrace?

Haplogroup distribution frequencies shifted smoothly along latitudinal gradients and the three lineages distinctively show a high-middle-low latitude distribution pattern (Figure 1). Based on the RDA analysis and ANOVA partition (Table 3), 15 out of the 20 tested BioClim variables had a significant (p < 0.05) relationship with haplogroup distribution frequencies for all the 43 populations (Table S2). This result indicated that climate obviously affected the genetic distribution of Cannabis populations. When the redundancy factors were removed, only MDL (Mean day length), Bio2 (Mean diurnal range), Bio8 (Mean temperature of wettest quarter), Bio13 (Precipitation of wettest month), Bio14 (Precipitation of driest month), Bio15 (Precipitation seasonality) formed a minimum subset of climatic variables. Based on the ANOVA analysis, MDL was the most significant factor influencing the haplogroup distribution frequencies (r2 = 0.6024, p < 0.001), and the subset of 6 climatic variables totally explained 74.2% of variation, and MDL accounted for the largest fraction of the total explained variation (20.8%).

and the subset of 6 climatic variables totally explained 74.2% of variation
Is your strain grow properly dialed in ?
TAJIKISTAN
https://weatherspark.com/y/148944/Average-Weather-at-Mazar-i-Sharif-Airfield-Afghanistan-Year-Round
MAZARI
ASSAM
https://weatherspark.com/y/149030/A...bhuvan-International-Airport-Nepal-Year-Round
NEPAL
KASHGAR
XINJIANG
There is a reef controller that can be set to MDL day length to correspond directly to a fish native habitat
This is effective in getting difficult to breed species to behave naturally
 
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acespicoli

Well-known member

Several plants were grown from a
local California “skunk” variety, which was likely a 3/4 NLD and 1/4 BLD hybrid
(e.g., Colombian/Afghan x Mexican)
and then all the females were crossed with a single select male.
A female identified as skunk plant number one was selected as the highest yielding and most potent,
and became the founder of all subsequent generations.

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while preserving landrace, there is also stacking to be done for elite genes
 

acespicoli

Well-known member
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acespicoli

Well-known member
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From time to time I come across some landrace and similar think its good to post them here
Please do they same if it crosses your minds as valuable information

The Cambodian lines were obtained in import bricks in the mid-late eighties, that smelled like Orange Peako Tea (and Moth Balls). It had a soaring high and was the 'best of best' import.
Different incarnations have been released over the years – this strain predates Reeferman Seeds going all the way back to the Prairie Fire Seed Company.
This strains took Charles years to get to the form it is now. OPC is a refined well stabilized cross of Nepalese Indica and Cambodian Sativa

Its unfortunately not uncrossed...too many hybrids
fine breeding work none the less
 
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acespicoli

Well-known member

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On Nigerian Silk

HT: What is your favorite haze? What’s your opinion on the Piff?
TDS: I love the Piff! Shit was crazy! I really prefer the Neville’s, A5, Cat Pissy Colombian, NYC Piff kind of Haze. I had a reputation. People had claimed of it being sprayed, or laced, or somehow contaminated with some other kind of drug. I had one guy who claimed he smoked some and took a piss test and tested positive for opiates. Most of the time it was wet, it was not flushed, it was really chemical-like in smell and taste, so the highs on it would be a little crazy sometimes. Then on top of that, the high from the strain itself made it more complex.”


HT: For those who might not know what “Piff” is, could you describe the look, smell, taste and effect for the world?
TDS: It was more of a cat piss, frankincense, church kind of smell. There were different types. The green Haze and the yellow/brown Haze is what we called it. The brown was always more chunky. It always had more of that cat piss aroma to it; compared to the green, it was more stringy. I believe the green is the black Haze. I had a cut of that. It has similarities to the cat piss Haze, but not as strong as the brown/yellow one. That was the one you wanted. It was stronger. I have not seen that in years, that yellow Haze. The green was pretty common.
 

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acespicoli

Well-known member
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MULLUMBIMBY MADNESS
Outdoor flowering: End of October

Supposedly of predominantly Thai origins (from the plethora of Thai sticks that flooded Australia from the beginning of the Vietnam War); a massive structure - some tall and elegant like Christmas trees, others wide and variegated and reputed to harvest up to 15 pounds; and a potent, uplifting high that has been likened to the best Haze.
 

acespicoli

Well-known member
Happy 420 :rasta: enjoy!

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Vietnam - Sativa Hybrids / Crossings​


Selections / Direct Descendents​


If you get ahold of this one try to share it around

Nam Black is a sativa variety from Dutch Flowers and can be cultivated indoors (where the plants will need a flowering time of ±70 days) and outdoors. Dutch Flowers' Nam Black is a THC dominant variety and is/was never available as feminized seeds.

Dutch Flowers' Nam Black Description​

Logo Dutch Flowers

I had the good fortune to get some VietNamese (aka Nam Black) seeds to grow out.
These babies are pure SATIVA:
Seeds were soaked in H20 overnight. Most sprouted in 24 hours. 100% germination. Put in Organic Soil under 120 watts fluros. Vegged 5 weeks. Very distinct LONG Sativa leaves, Lime Green color. Plants develop into drooping umbrella form. Under HID's, plants STRETCH! Mine ended up at 2 1/2 - 3 1/2' in 3 gallon pots. Very branchy. Two phenotypes: One taller, leafier, more branching; the other shorter but heavier flowering, especially on the main stem. Fluffy white pistils. Plants start "putting on the weight" after 5 weeks. Final time 9 - 11 weeks.
Final product is "old time Sativa". Fruity Mango flavor. High is super Trippy Sativa like weed from the 70's. High can bring on paranoia, racing heart beat and hallucinations for those not used to it. Not for light weight smokers!!!!! This stuff is EXACTLY what I remember was around during the 70"s. You can almost hear the whoomp-whoomp of the Nam choppers. A great outdoors "Summer Day smoke". Just don't smoke it before your landlord or Mom comes by.... Hehehhehehe....
A 10 in my book! Sensi

These were from AF who asked me to test em.
These babies ARE NOT your typical Seed Bank seeds. They're pure Sativa, so they need tons of light, and patience. HOWEVER... for those willing to wait the 10 or so weeks, or have access to outdoor fields, its the real thing.
Indoors during the last few weeks you really need to use an extra fan, cause these babies will suck up water! You aint gonna over water these girls - they just pass it thru their huge Sativa leaves. Genetics for the Mecong Delta...
The high is exactly like the stuff I remember from the mid 70's. I recall some "body bag" weed (don't ask)that had a similar high: every puff took ya to another level, and there was this hum or buzz sound-noise in your head! Best smoked with a good friend at your side, if ya know what I mean. Odds are maybe one of you won't freak, hehehhe...
Yup, right up there with the old Columbian, Thai, and Panama stuff.
If you're into SCROG, these are it - very branchy and a million bud sites. Sensi

Nam F1 (Vietnamese sativa hybrid, aka Vietnam Black, aka NAM weed) -Original F1 cross: -Male Northern Vietnam/China Boarder (indica influence) -Female Southern Vietnam outskirts of Saigon (truebreeding pure Sativa NAM) Breeder's description: Originating from Vietnamese genetics brought back to North America in 77, she's an extremely potent exotic sativa. NOT RECOMMENDED FOR MEDICIAL USERS: usually resulting in shortness of breath, difficulty breathing, raised blood pressure, leans towards paranoia. Her sweet tropical ripe mango scent and sickly sweet taste will speak for itself. Vigorous strong brancher and top heavy - support recommended. A very heavy yield compensates for a longer flowering period. Indoor Specs: Flowering time: 9+ weeks, Height 150 cm, Yield: 1+ gm/watt Original Auction Description

here's my experience with the Nam:
Can you find good Mom's from 10 seeds? Most definitely! I had 10 for 10 germ, and btw, it was definitely one of the fastest germinating strains I've run across in years.
I ended up with 6 females, 4 males. Of the 6 females, I kept 3 with the best flowering characteristics, due to space limitations.
There are 2 phenotypes: One produces more bud sites early on, close to the main stem, and is less leafy. The other is leafier, more branchy, but produces bigger buds later on, particularly from side shoots. Either one is most suited to scrog - there's lots of stretching and branching. ( I went bush style route to "test' the strain, and they ended up stretching 4x initial 12/12 height!) I have one Mom that probably could have filled a small screen all by itself! (May have pics soon...) This is a low odor strain: little odor early on, later during heavy flowering a very subdued Mango odor. Being an almost pure Sativa, don't expect heavy "frost trichomes", but dont let that fool ya - this baby builds up the thc levels. High is rocket up, visual trippy. Takes a bit to "get yer bearings" if you're not used to Sat highs, hehehehe.. I would suggest a minimum of 400 as it likes to just keep on stretching and making more and more buds, so light penetration is the thing. Like I said, the perfect Scrog plant. Fert requirement is nominal, I would suggest more N early on and back off the N later on to keep the stretch down. This is a 10 to 12 week plant, so don't be choppin her down at 50 days! Sensi

Questions on Nam Black:

1. How uniform is it? How are the odds of getting a really nice mom (and dad) out of 10 ?

2. What planting density do you recommend in scrog for this plant. The plant in the pics covered how much space when flowered with no veg time in the chamber? I'm trying to get a feel for the timing/density with this strain for the set-up AF is building right now (2'wx4'lx4'h cabinet, 400hps on a linear mover, water-cooled light).

3. How strong is the odor? Anything in particular to be aware of? Any unusual nute preferences?

Short version:

1. very uniform. 4 to 6 females from 10.
2. 3 plants/ft2, 7.8 ft2, easy to time flush.
3. strong pungent, but easily manageable. Impatience = beware.

Long version:

1. She's very uniform in regards to potency, height, leaf structure, bud structure, and most general flowering givens with a rare exception. The main difference in phenotypes I've noticed from the norm are the odd "nothing but bud" single donkey dick like individuals, usually identified by the short, somewhat squat and bushy veg appearance (SOG) nearly butt naked when fully mature. Of the 10 from the above picture, 6 were males, 4 were females. Of the 4 females, 3 were very identical in appearance and in performance (ie.. strong branching, uniform tight internodal spacing, tall, water guzzling vigorous growth,) all great flowering prospects. I've made the effort to clone and keep all 3 mums as new additions in the veg room, for future cloning. The remaining female is the odd "nothing but bud" pheno, which btw, is looking really nice even scrogged right now. I'll try to post a picture of this pheno so you can easily spot it, as soon as reasonably possible. The fathers were all very uniform, though I didn't spend enough time with the males to able to give you a fair and more in depth description. So, to answer your question, ... even with my bad luck, I've managed to secure 3 outstanding ScrOG mums, even faced in a low fem ratio predicament. You should end up with 4-6 uniform mothers to painfully choose from, out of 10.....

2. Given a standard basic flat horizontal scrog, with the screen set 12" above the medium : 3 plants per ft2 works well, done only with MATURE clones. The ones in the pics covered 100% of the available 7.8 ft2 canopy planted at a density of 3 plants per ft2, with absolutely NO veg time in the chamber (done with 6" single topped clones). The buds ranged from 2-18 inches long with the average bud measuring between 8-12 inches long. The larger the plant at induction, the more likely you'll get away with using fewer plants, i.e.... additional veg time. Your friend may want to take into consideration the ventilation requirements which may present themselves amist growing in such a dense bud canopy. His 4x2 space gives the perfect opportunity to slide out the centre 24" module which leaves just enough space to confortably train inside the cabinet, a great opportunity to save work and training time, and of course, taking advantage of vertical screens ect...Done properly, your friend's 400W water cooled light should produce an abundance of outstanding buds on the heavy side. Timing should be easy with an overcrowded excessive amount of shoots "that you have to clip away!" that should begin to rise when they begin to bulk in the 6th week. The mimum reccommended finishing time is 9-10 weeks.

3. The scent is very strong, but not enough to worry about. I've found that all will exhibit this trait fairly well, though I wouldn't say the smell isn't as overly intense like many of the "skunk" varieties avail. Nothing to lose sleep over. But, be aware of premature flowering (12/12 induction "pre"- alternating phyllotaxy ), which is EASIEST trigger for hermaphrodism. NEVER induce flowering until alternating phyllotaxy. Can seem forever on a near pure sativa, .... but a mistake unfortunately made by many, myself included. Further veg time followed by re-flowering always proves that the trigger is environmental rather than genetic, at least with this strain. As for nutes, I feel it's one of the most vigorous plant I've ever grown, very hardy and forgiving. It's done well in the past using dirt bio, dirt chem, dirtless hydro, and looks very promising in DWC hydro and DWC aquaponics "so far" (even for a hydro-illiterate, like me) LOL. You should easily excell my efforts with your hydro experience I feel that most ppl will consider her a waterhog, and hardy and tolerant (nominal req's for survival, at the same time it handles force feeding well). Overall, an easy plant to grow and evolved, well,... ideally for scrog.... Ultimate
 

acespicoli

Well-known member

Description​


Uzbekistani IBL

This pure Uzbekistani inbred line is a collaboration release with Cannabiogen that was facilitated by our good friend Bodhi. A portion of the proceeds from the sales of these seeds will go to Charlie Garcia & Cannabiogen.



These seeds were produced with an open pollination of roughly 150 plants to keep the integrity of the line intact for the next generation.





21 Regular Seeds per pack.

:rasta: spread the love


Uzbekistan - Indica Hybrids / Crossings​


Selections / Direct Descendents​


 
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acespicoli

Well-known member

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Not sure its accurate and timely but still interesting

How they did it — The researchers studied 110 genomes of Cannabis sativa using molecular analysis and “next-generation DNA sequencing” according to Fumagalli.

From their DNA analysis, the researchers build phylogenetic trees that show the relationships between and evolution of four genetically distinct groups of cannabis.

  1. Basal cannabis — This group is “sister to all other cannabis” categories, including all human-grown or “cultivated” hemp and psychoactive cannabis in the world. It includes wild plants and traditional cannabis hybrids, known as “landraces,” found in modern China.
  2. Hemp — This group includes all hemp varieties found around the world. Hemp is a variety of Cannabis sativa that is distinguished from other cannabis strains by its lower levels of tetrahydrocannabinol (THC) — the psychoactive ingredient that makes cannabis such a potent drug. Hemp, unlike its psychoactive counterpart, is not typically considered a drug and was traditionally used to make fiber for clothing and other materials.
  3. The first group of “drug” cannabis — This group includes wild strains of cannabis with drug-like properties similar to marijuana from China, India, and Pakistan, as well as one cultivated cannabis variety from India.
  4. The second group of “drug” cannabis — This group includes varieties of cannabis with drug-like properties that have been cultivated around the world.
This crucial basal cannabis group hadn’t been detected in previous research — a fact that Fumagalli found “very surprising.”

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A map from the study showing the historical distribution of different groups of cannabis around the globe.
Ren et al.
What they found — Through these genetic groupings, specifically, the basal cannabis grouping, scientists learned:

  • The origin of cultivated or domesticated cannabis can be traced to East Asia, including parts of modern-day China. The finding challenges previous research stating that cultivated cannabis originated in Central Asia.
  • The split between ancient basal cannabis and modern cultivated cannabis occurred roughly 12,000 years ago, placing cannabis in the distinguished categories of one of the first cultivated crops on Earth
  • These early cultivated cannabis crops formed separate hemp and drug cannabis genetic groups about 4,000 years ago
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acespicoli

Well-known member

SubCools Jack the Ripper Description​

Logo SubCool’s The Dank SubCool’s The Dank Jack the Ripper
As good as JC bx was, I learned a lot in 6 years breeding and growing almost full time and I was confident I could find a better male using patterns to find the recessive drug traits. So instead of continuing a cube I wasn’t 100% satisfied with the outcross I decided to start again using two different lines to establish the best. JTR is the first outcross to be completed using a Spacequeen male; the second will be a Cindy99 outcross. The goal here is to establish the best possible outcross to cube back to JCf1. The cool part is the outcrosses are sometimes better than the parent strains, I feel this is the case with JTR. The Lemon tart of JC has combined with the candy mango flavor of the Spacequeen to create a resinous marvel. Maintaining JC’s heavy structure and potency the female dominated this cross with the exception of adding some sweet mango flavor and smoothing out JC’s harsh toke. I will be doing my best to enter this strain in the 2006 Cannabis Cup.

* Phenotypes: Moderately stable with heavy Jacks Cleaner traits.
* Height: Tall with long stretch/ Colas swell late
* Yield: Medium / Moderate trim work
* Indoor / Outdoor
* Best way to grow: Topped and placed in bud early due to stretch.
* Harvest Window: 8-10 weeks
* Sativa/Indica: 80/20
* Hybrid: Pluton X Purple Haze X Lambsbread X NL X Jack Herer X Romulan X Cindy99BCGA
* High type: Intense, trippy, visual, phase shifting, increased heart rate, heavy crash increased appetite, pain relief, paranoia
* Lemon mango pine hash / Taste like lemon hash
* 100% Full melt extreme potency



The effective population size (Ne) is a number that, in some simplified scenarios, corresponds to the number of breeding individuals in the population. More generally, Ne is the number of individuals that an idealised population would need to have in order for some specified quantity of interest (typically change of genetic diversity or inbreeding rates) to be the same as in the real population. Idealised populations are based on unrealistic but convenient simplifications such as random mating, simultaneous birth of each new generation, constant population size, and equal numbers of children per parent. For most quantities of interest and most real populations, the effective population size Ne is usually smaller than the census population size N of a real population.[1] The same population may have multiple effective population sizes, for different properties of interest, including for different genetic loci.


The effective population size is most commonly measured with respect to the coalescence time. In an idealised diploid population with no selection at any locus, the expectation of the coalescence time in generations is equal to twice the census population size. The effective population size is measured as within-species genetic diversity divided by four times the mutation rate μ {\displaystyle \mu }
\mu
, because in such an idealised population, the heterozygosity is equal to 4 N μ {\displaystyle 4N\mu }
{\displaystyle 4N\mu }
. In a population with selection at many loci and abundant linkage disequilibrium, the coalescent effective population size may not reflect the census population size at all, or may reflect its logarithm.

The concept of effective population size was introduced in the field of population genetics in 1931 by the American geneticist Sewall Wright.[2][3]



Population Genetics Glossary

Genetic Diversity and Population Structure of Cannabis ...

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National Institutes of Health (.gov)
https://www.ncbi.nlm.nih.gov › articles › PMC7518120


by J Zhang · 2020 · Cited by 10 — Three hundred ten alleles were identified, and the major allele frequency ranged from 0.26 to 0.85 (average: 0.56),

Abstract​

Cannabis has been used as a source of nutrition, medicine, and fiber. However, lack of genomic simple sequence repeat (SSR) markers had limited the genetic research on Cannabis species. In the present study, 92,409 motifs were identified, and 63,707 complementary SSR primer pairs were developed. The most abundant SSR motifs had six repeat units (36.60%). The most abundant type of motif was dinucleotides (70.90%), followed by trinucleotides, tetranucleotides, and pentanucleotides. We randomly selected 80 pairs of genomic SSR markers, of which 69 (86.25%) were amplified successfully; 59 (73.75%) of these were polymorphic. Genetic diversity and population structure were estimated using the 59 (72 loci) validated polymorphic SSRs and three phenotypic markers. Three hundred ten alleles were identified, and the major allele frequency ranged from 0.26 to 0.85 (average: 0.56), Nei’s genetic diversity ranged from 0.28 to 0.82 (average: 0.56), and the expected heterozygosity ranged from 0.28 to 0.81 (average: 0.56). The polymorphism information content ranged from 0.25 to 0.79 (average: 0.50), the observed number of alleles ranged from 2 to 8 (average: 4.13), and the effective number of alleles ranged from 0.28 to 0.81 (average: 0.5). The Cannabis population did not show mutation-drift equilibrium following analysis via the infinite allele model. A cluster analysis was performed using the unweighted pair group method using arithmetic means based on genetic distances. Population structure analysis was used to divide the germplasms into two subgroups. These results provide guidance for the molecular breeding and further investigation of Cannabis.

The Genetic Structure of Marijuana and Hemp - PMC

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National Institutes of Health (.gov)
https://www.ncbi.nlm.nih.gov › articles › PMC4550350

by J Sawler · 2015 · Cited by 291 — Using 14,031 single-nucleotide polymorphisms (SNPs) genotyped in 81 marijuana and 43 hemp samples, we show that marijuana and hemp are ...

Abstract​

Despite its cultivation as a source of food, fibre and medicine, and its global status as the most used illicit drug, the genus Cannabis has an inconclusive taxonomic organization and evolutionary history. Drug types of Cannabis (marijuana), which contain high amounts of the psychoactive cannabinoid Δ 9-tetrahydrocannabinol (THC), are used for medical purposes and as a recreational drug. Hemp types are grown for the production of seed and fibre, and contain low amounts of THC. Two species or gene pools (C. sativa and C. indica) are widely used in describing the pedigree or appearance of cultivated Cannabis plants. Using 14,031 single-nucleotide polymorphisms (SNPs) genotyped in 81 marijuana and 43 hemp samples, we show that marijuana and hemp are significantly differentiated at a genome-wide level, demonstrating that the distinction between these populations is not limited to genes underlying THC production. We find a moderate correlation between the genetic structure of marijuana strains and their reported C. sativa and C. indica ancestry and show that marijuana strain names often do not reflect a meaningful genetic identity. We also provide evidence that hemp is genetically more similar to C. indica type marijuana than to C. sativa strains.
 
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acespicoli

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In population genetics, the Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem, or law, states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. These influences include genetic drift, mate choice, assortative mating, natural selection, sexual selection, mutation, gene flow, meiotic drive, genetic hitchhiking, population bottleneck, founder effect, inbreeding and outbreeding depression.



In the simplest case of a single locus with two alleles denoted A and a with frequencies f(A) = p and f(a) = q, respectively, the expected genotype frequencies under random mating are f(AA) = p2 for the AA homozygotes, f(aa) = q2 for the aa homozygotes, and f(Aa) = 2pq for the heterozygotes. In the absence of selection, mutation, genetic drift, or other forces, allele frequencies p and q are constant between generations, so equilibrium is reached.

The principle is named after G. H. Hardy and Wilhelm Weinberg, who first demonstrated it mathematically. Hardy's paper was focused on debunking the view that a dominant allele would automatically tend to increase in frequency (a view possibly based on a misinterpreted question at a lecture[1]). Today, tests for Hardy–Weinberg genotype frequencies are used primarily to test for population stratification and other forms of non-random mating.

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Hardy–Weinberg proportions for two alleles: the horizontal axis shows the two allele frequencies p and q and the vertical axis shows the expected genotype frequencies. Each line shows one of the three possible genotypes.
 
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