Breeding Q????

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Just a Dawg
Jan 6, 2006
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I've been reading a little on this link from stoney Bud.

Now my very uneducated and possibly the dumbest question I have ever asked goes as follows:

If through plant (mother and father) selection process. once bred to make a cross for the desirable strain traits. after going through the complete process in obtaining a solid strains of mother and father with certain fixed traits. Will envirnment play a critical role in keeping those traits in the cross that was developed? (I don't mean stresses, I mean maintained correct conditions). Or will the breeding process make each seed become "altered" (like no twins are truley identical)? or both. So in a nut shell: will each seed lose a certain "fixed" characteristic that was trying to be acheived by selecting the parents correctly no matter what you do over a course of multiple generations(assuming inbreed the strain)?

Hope my crazy question made sense.
not sure that this adresses all of your question directly, but it provides food for thought.

Phenotypic expression

The malleability of phenotypic expression among the Sativa/Indica crosses must also be noted. The variability of phenotypic expression among the f2 generation of a truly polar (pure Sativa/pure Indica) P1 cross is quite phenomenal. The second generation f2 crosses will exhibit the full spectrum of possibilities between the original parents – extreme Indica, extreme Sativa, and everything in between.

However, regardless of any particular phenotype selected from among this given f2 cross, future generations may drift radically. Depending on the presence (or lack) of a number of environmental triggers, an f2 Indica phenotype may be coaxed more toward Sativa traits, or an f2 Sativa phenotype may be coaxed more toward Indica expression. The key is environmental conditions.

This is what distinguishes the truebreeding, ancient acclimated, region of origin varieties – especially the tropical and equatorial Sativa – from the crosses that have happened since. The ancient specimens have a much narrower genotype range, and therefore a more specific phenotype than their contemporary crosses despite environmental conditions. It is up to future adventurers to provide the best possible environmental considerations, along with the best possible genetic considerations, in order to resurrect the legendary happy flowers of yore.

Inducing Sativa

After many years of first-hand experience breeding herb indoors as well as outdoors, I am of the opinion that the two most influential factors involving phenotypic variation and expression among current indoor herb breeding projects are the photoperiod (hours of light per day) and the angle of light in relationship to the growing plant.

Specifically, I find the single most powerful influence to the Indica dominant phenotype is the traditional 18/6 veggie cycle and 12/12 flowering cycle. The 18/6 veggie and 12/12 flower cycle is an attempt, however poor, to mimic the Indica-producing photoperiod. It is my belief that this light cycle strongly influences for Indica phenotypic expression.

Sativa phenotype characteristics will manifest under a more equatorial photoperiod, closer to a 13/11 veggie cycle and an 11/13 flower cycle. This is the light timing range to use to elicit more Sativa dominant expression from your plants.
Hick said:
not sure that this adresses all of your question directly, but it provides food for thought..

Exactly, what I was refering to.

However, regardless of any particular phenotype selected from among this given f2 cross, future generations may drift radically. Depending on the presence (or lack) of a number of environmental triggers, an f2 Indica phenotype may be coaxed more toward Sativa traits, or an f2 Sativa phenotype may be coaxed more toward Indica expression. The key is environmental conditions.

This answers my question right here. Now the Hard part of centralizing the "specific trait".

After many years of first-hand experience breeding herb indoors as well as outdoors, I am of the opinion that the two most influential factors involving phenotypic variation and expression among current indoor herb breeding projects are the photoperiod (hours of light per day) and the angle of light in relationship to the growing plant.

The key note I notice in this read is not only the length of the photoperiod, but the actual angle of light plays a crucial role in development of the strain.

hmmm? so to be truly hypothetical: in an indoor lighting schedule.. to truly develop certain charecteristics and keep them as a constant. you would have to take into account the lighting position, spectrum, and intensity in certain increments to imitate the suns motion during daylight hours. To only be somewhat accurate would be a project in itself (in any environment).

Thank you so very much Hick. Gave me a ton of food for thought. Now the hard part. figuring all this stuff out and seeing if it could be done. (I ordered a true indica strain and that is why I am so curious).
here's another li'l tidbit of interest from DJ..

Even with a known high-THC clone, THC level and cannabinoid ratios may change depending on environmental conditions.

What defines drug strain cannabis is the plant's ability to convert cannabidiol (CBD) or possibly cannabichromene (CBC) into THC.1 If we as growers do not provide the plant with reason to make this conversion it likely will devote its energy elsewhere, to aid in its survival.

Environmental Influence

It takes high quality genetics to produce high quality marijuana, but genetics is only half of the equation. The genetic structure (genotype) only plays 50% of the role in determining the appearance and quality (phenotype) of a given plant. The other half is determined by environmental conditions such as light, temperature, humidity and soil nutrition. All these factors play a role in both the physical and chemical nature of marijuana's trichomes.

The best way to take a look at how environment affects THC production is to look where on the planet cannabis has naturally adopted a high THC profile. As cannabis has spread around the world it has taken on many different traits to help in its adaptation to varied areas. The best drug varieties have always been found at equatorial or high altitude locations. The one thing which both of these variables have in common is high light intensity and a large amount of ultraviolet (UV) light in the spectrum.

Recent Swiss trials in outdoor plots of clones grown at different altitudes have shown that there is correlation between higher altitude and increased potency (although there seems to be a trade off in yield). This likely means that THC-rich resins act to protect the plant and its seed from both higher light intensities and ultraviolet presence. It's no surprise that cannabis has developed a chemical to protect itself against the Sun's damaging UV rays, as they can be injurious to all forms of life.

In a plant's search for survival, energy put towards unneeded processes is wasted energy. Therefore a high-THC plant grown in a low THC environment will likely produce a medium THC result.

Humidity also plays a role in plant resin production. Although some potent equatorial strains do seem to occur in high humidity areas, most high-test land races have evolved in drier areas, like Afghanistan. The aridity of the areas of Afghanistan where Indica strains have evolved is quite apparent by the trait of large dense flower clusters. This would only be an advantage in an area of low humidity, as flowers will mold in anything more.2

There are many examples of non-cannabis plants producing resins in order to protect themselves from drying out. The waxy coating on cacti and other succulent plants is a prime example.3 Marijuana flowered in humid conditions will often have a longer stalk on the glandular trichome than the same strain grown in drier conditions. While this may give the appearance of being very crystallized, it will likely contain less THC than the same plant grown in a drier environment. Another problem with longer trichome stalks is that the gland heads are more likely to break off during handling.

Flushing: pros and cons

Much time and thought has been put into the feeding needs of each part of marijuana's life cycle, yet for some reason the final stages of resin development always seem to be ignored. But the vegetative period of plant growth is only setting the platform for us to produce the trichomes that we are after.

Flushing in particular seems to be something that is over-emphasized by many of today's growers. Many growers "flush" their plants with straight water or clearing agents during the final weeks before harvest in an effort to improve taste and smokeability. The theory is that this forces the plant to use up stored nutrients that may affect these qualities. Although this is certainly true to some extent, what many are forgetting is that not all nutrients can be moved within the plant.

Nitrogen, which is the main factor in poor-tasting bud, can be moved within the plant. If not present in the root zone a plant will take it from the older leaves to support newer growth. Calcium, however, is a nutrient that cannot be moved within the plant, if it is not present in the root zone it is not available for growth. Little research has been done on nutritional requirements of cannabis during the final stages of flowering, but it seems likely that calcium is vital as it is crucial in cell division. A calcium deficiency at later stages could therefore adversely affect trichome production.

This is not as serious of a concern for soil-based growers, as lime or other calcium sources which are mixed into the soil likely will provide sufficient nutrition even while flushing with pure water. But hydroponic growers using very pure water sources with little naturally occurring calcium could have problems. Flushing is certainly a valid technique, but is easily overdone and is not a quick fix for overfeeding earlier in the flower stage.

Some studies have shown that high potassium levels have a negative influence on THC production,4 which would correlate to the general belief that while hemp crops uptake more potassium than phosphorous, the reverse seems to be true for drug and seed cannabis crops.2 A study on how to minimize THC levels in hemp crops showed that THC levels in newer leaf growth decreased as nitrogen levels were increased.5 As no THC measurement was taken from floral clusters we can only speculate that the same would likely hold true in buds. This would also explain the good results that most growers have flushing their plants, as nitrogen is the nutrient most easily flushed from the soil.

Companion planting

Much research is still needed on the interrelationships of plants in the garden. Little is known about common vegetable garden plants effect on each other, let alone how they may react with cannabis.

Growing certain plants in proximity to each other has been documented to cause noticeable effects on growth, both positive and negative. The main companion plant that has attracted interest with underground marijuana researchers is stinging nettle (Urtica dioica) which has been said to increase essential oils in many plants.6
Wow, that explains why my bud was better when I lived up north in the mountains. As far as outdoor growing.

I have to re-read the flushing thing a few times though. I can see it, just not quite getting it yet.

Thanks Hick.
Ok, I've been reading an assload lately on this topic
I have a couple of questions.

1. Does the Male or the female plant dictate which genotype charectristics are more predominant? To make my questions a little more clear. Lets say I make a cross. Isolating which charecteristics I want would that be dictated by which one I use as the male and which one is the female? I know this is varied, but I hope you see my question.

2. Does the same genotype charecteristics stay the same (not gender of course) through out the plant or will these be a different arrangment over the whole plant? (sorta like maternal twins, similar charecteristics, but many variences)

3. will the phenotype charecteristics over a course of generations (but keeping the original no further crosses) change and also change the genotype of the cross that was orignially made because of environment chages? or would this be answered by researching Mendels (I think how thats spelled) Law more?

I know these are relatively dumbass questions. but nothing I found gives me an idea how this aspect works. (or may be I am that dumb and couldn't interpret it and should go back to night school on botany)
#1..There are traits/characteristics that are "believed" to be predominately controlled according to the sex.(I think thats what you're asking) Flavor/odor dominated 'usually' by the male. Yeild/growth pattern, more so by the female in the following generation. Those are examples. I'm not certain of there validity.
I believe DJ has written"his" theories on this somewhere. I'm certain that I've read on it. See what I can find on the 0' HD.
#2 I'm not following this one, sorry. "genotype remain the same throughout te entire plant" ? Now I'm the dense one..:p
#3.."My take" on this. (Again if I'm 'getting' the question.) A stable truebreeding strain shoudn't vary excessively. You will have various pheno's from time to time. Both due to environmental conditions and recessive qualities that will rear their heads throughout the generations.
This assuming you make all of the correct choices in selecting parents.
selecting[/i] parents.

No your not the dense one. I am the dumbass one.:)

Yes selecting the right plants is critical that is a givin.

Assuming (which I hope I am not make an "ASS" out of "U" and "ME" couldn't resist.) assuming #1 is correct.
my #2 question was if this is the case and the certain charecteristics in the genotype are made. will the genotypes such as flavor and aroma vary from seed to seed drastically by which charecteristics where established with each bud pollentation. or will it be a common average? Assuming conditions are kept the same.

Thanks Hick you have been a valuable asset on this thread. you helped make some of these things make some sense.
shit! mutt yer gettin' me in over my boottops.

I'm not sure that I can answer that. But I think the answer can be worked out here..
I keep remembering "genotype determines phenotype"(environmental influence excepted) and NOT vice versa.
Dominance, co-dominance, incomplete dominance. And learning how to recognize which of these you're dealing with, is about as deep as my shallow mind dares to venture.
sorry dude. I didn't want your mind to fry and a buzz kill to form. My apologies. I'll work it out myslef. shit dude. don't have a stroke.;) I'll get the info. and post it. This just has my curiosity. I love great info. and you Hick (if you notice) have been the only one to contribute. props to you dude. You are the mac daddy on this thread. Thanks you got me off on the right start.
I been readin'' :eek:..ya peaked my interest again. There was a time, when I was gathering this info, that I had a project. I really crammed the info, trying to grasp it all and conduct a successful breeding project. I didn't do well.
Oh, I made successfull crosses that resulted in very nice hybrids. Even managed to select a very good male that seemed dominant in his characteristics. But once I started growing out the f2's and selecting for x's. Things went south.
Probably the most important factor in beginning any project is being "positively certain" of the genetic makeup of the P1's. Purity (homozygous) are so important to avoid selection difficulties.. IMHO, a homozygous strain is alnost impossible to find these days. There are a few, but most everything has been developed. Leaving you with a 'mud puddle' for a genetic pool.
Looks like a great add to the library..
Well, time to bring this one back up.

Hey Hick this is easier questions. :D

When pollenating a female is it more prone to mold problems?
I read that the pollen can mold very easily.

Are there any pics you know of that show mature seeded bud. or do you wait until the plant itself "dies". then its ready and drops its seeds like everything else in nature?
mutt, when "seed makeing", keep the pollinated plants on a "full" fertilizer schedule througout the entire flowering process. NO flush.
N and K are essential in producing fully formed, mature, viable seeds. A minimum of four weeks from pollination to mature seeds. Personally, I like to pollinate early on. As soon as the fem has a good amount of pistills forming a head. I like to wait untill the bracts are split and seeds fall freely with the slightest touch.
I've not experienced a problem with pollinated buds molding, any more than un=pollinated.
Pollinated plants will, however mature/finish faster than un-pollinated. Their "mission" in life is complete. No 'need' to prolong the life cycle.

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