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Post by Joseph Lofthouse on Dec 12, 2012 15:46:48 GMT -5
5. Epigenetic changes in how the genes are expressing.
6. Gardener learning the needs of the plant and better meeting those needs.
7. Changes in the environment, or soil, or biota which favor better growth.
I guess it was a blessing for me to have genetically identical sisters. Makes it easier for me to see how the environment, and cultural factors influence genomic expression. I don't have to resort to mutation to explain differences between my cloned sisters, or the improvement of garlic clones grown in the same garden for years.
Still, there are limits to non-sexual adaptation... No matter how many times I replant elephant garlic, the offspring always produce less food than what went into the ground.
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Post by terracotta on Dec 14, 2012 14:43:09 GMT -5
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Post by nicollas on Mar 15, 2015 10:33:15 GMT -5
Try to figuring out more about all the terminology, here is what im understanding (or what fits my mind best) :
* A variety (OP) has a phenotype that is quite strict (in terms of plant and fruits characteristics). The genotype is homozygous and shared by individuals (clones), in imbreeding species. For outcrossers genes are homozygous for the fixed phenotypic features, but there is still "hidden" heterozygous genes to provide vigor or avoid imbreeding depression.
* A variety (F1 hybrid) is defined by its two parents (usually unknown from public) and is the result of their crosses. The phenotype and genotype of the F1 is always the same, but it does not breed true (not fixed), and there is a lot of heterozygous genes.
* A seed mixture or seed blend is a mix of several varieties in a packet.
* A grex is a population of plants that has a good genetic diversity, usually several varieties, or/and seed mixtures, imported grex or landraces, and their inter-pollinated subsequent generations
* A landrace is population of plants that has a good genetic diversity coming from its origin (usually a grex) and its management (adding new varieties, seed mixtures, greges, or seeds from previous years), whose main driving force is selection (weather, soil, pests, diseases, gardening patterns) in the same place for a sufficent numbers of years that the place has shaped enough the population. The genotype and phenotype are more heterozygous/diverse than for a variety. The main goal is a good balance between adaptation to average/long term conditions of the place (best yielding genotype) and to unusual conditions of each years (genetic diversity). So the result is that a landrace should be performing better on average.
Greges and landraces are characterized by hight genetic diversity, but the main difference is that the main driving force of greges is genetic diversity generation (expansion) whereas the one of landraces is selection (contraction) - even if there is still some external genetic input each year.
A landrace can be used as a foundation for a grex.
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Post by nicollas on May 29, 2015 6:24:10 GMT -5
From Organic Crop Breeding by Edith T. Lammerts van Bueren, James R. Myers
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Post by reed on May 29, 2015 9:09:44 GMT -5
On the Peace Seeds web site Dr. Kaupler says "Landraces are cultivated wild species". I have columbine, asters, Virginia Bluebells and summer phlox that meet that definition and that now have larger flowers with more color diversity that when I first started cultivating them but they all came from just wild ones I found and brought home.
I also have peonies, iris, daffodils, roses and garlic that I collected wild but I don't think they qualify because they were survivors found around ruins and not actually wild. Their phenotype has not changed over they years probably because they don't propagate by seed.
Again going by Dr. Kauplers definitions my corn is already a Grex because it is a mix up of lots of kinds and in future years it will continue to be a mix of F1 through Fx hybrids. I don't ever really want it to settle into a completely stable variety because I want be able to keep growing it indefinitely in populations smaller than recommended but free of the issue of genetic depression.
The before mentioned columbine might also be bordering on Grex because one time I planted some McKana's Giant Columbine and now I get all kinds of mixed up phenotyoes when it comes to flower structure and color.
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Post by rowan on May 29, 2015 14:06:01 GMT -5
Coming from many generations of farmers I always grind my teeth at 'landrace' definitions on this forum. I know I will attract some ire and differing opinions but the definition that most farmers know is:
A landrace is a defined variety that is adapted to a specific area. For example, say, Black Russian tomato which is grown for many years in different areas, each area grows Black Russian but if you take a Black Russian from one area and plant it in another it will not do as well. Each area is still growing the same variety, and it looks and tastes exactly the same, but each area has its own landrace of that variety.
In my whole life farming and breeding animals and plants, until it started on this forum, I have never come across anyone breeding a mishmash of varieties or types and calling it a landrace. If you are going to do that, then make something that breeds true and give it a variety name, then you might call it your landrace of that variety.
Just my 2c and I won't say another word on it as I know it goes against what many people here believe.
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Post by castanea on May 29, 2015 18:50:18 GMT -5
Coming from many generations of farmers I always grind my teeth at 'landrace' definitions on this forum. I know I will attract some ire and differing opinions but the definition that most farmers know is: A landrace is a defined variety that is adapted to a specific area. For example, say, Black Russian tomato which is grown for many years in different areas, each area grows Black Russian but if you take a Black Russian from one area and plant it in another it will not do as well. Each area is still growing the same variety, and it looks and tastes exactly the same, but each area has its own landrace of that variety. In my whole life farming and breeding animals and plants, until it started on this forum, I have never come across anyone breeding a mishmash of varieties or types and calling it a landrace. If you are going to do that, then make something that breeds true and give it a variety name, then you might call it your landrace of that variety. Just my 2c and I won't say another word on it as I know it goes against what many people here believe. "A landrace is a defined variety that is adapted to a specific area." You nailed it. I'm not sure anyone disagrees with you significantly. I'm not even sure there's that much to disagree about. A landrace may have arisen from a great deal of genetic diversity or it may have arisen from very little genetic diversity. There may have been a great deal of human intervention or no human intervention. The plant may or may not have been a cultivated crop. The only thing that matters is that it is adapted to an area and breeds true in that area. If the landrace was arrived at by human means, then it arguably is also an adaptivar. In India, Pakistan and Afghanistan you can find numerous cannabis landraces. Some of these appear to have been created by humans and others appear to have evolved/adapted without human intervention, but they are all landraces. There are some specific definitions that have been adopted by researchers in specific areas that are not very broad and I am not disputing the utility of those definitions for those researchers, but the definitions do not necessarily have much currency beyond those areas of research. Crop scientists and those with a crop science background, define landraces in terms of cultivated crops. Their limitation to cultivated crops is fine for their purposes but there are non crop plants that have all the other elements of a landrace and there is no need for non crop scientists to limit our definition to crops. |
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Post by Joseph Lofthouse on May 29, 2015 20:44:23 GMT -5
I bet that less than 1 farmer in 100 in this area would even know that a landrace has anything to do with growing crops. A landrace is something you do in a motorized vehicle. A landrace is something the kids do in the park for Memorial Day.
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Post by castanea on May 29, 2015 23:38:16 GMT -5
That's probably true in most of the USA.
I am really glad to see cannabis cultivation coming out of the closet, both figuratively and literally. There are some very dedicated and knowledgeable plant breeders in the cannabis world and some have been looking all over the world for established cannabis landraces. Making new cannabis landraces is an entirely different story since even most progressive state laws still prevent that goal from being openly pursued.
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Post by nicollas on May 30, 2015 1:55:16 GMT -5
My problem with some of the def is that landrace is associated with something of the past or for remote places where varieties have not yet be adopted by farmers.
So how to describe Joseph's work i not by landraces ? There is no random pollination to me because even if it is open pollinated mothers and fathers are chosen more or less precisely by Jospeph. I think landracing-the-Joseph-way is called evolutionnary breeding but the latter does not translate well to design a handful of seeds.
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Post by Al on May 30, 2015 17:55:18 GMT -5
A little known word that might be useful in talking about landraces is; AUTOCHTHON. Which just means aboriginal, indigenous, native to a region. The roots of the word just mean something like 'of the soil'.
I consider myself AUTOCHTHON to The British Isles as some of my ancestors have lived here a very long time. Most Old World human populations / nationalities / races have been fairly closed gene pools for long periods. So perhaps for a plant population to truly be a 'landrace' after the founding plantation is established a century or two must elapse with only limited new genetic introductions?
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Post by castanea on May 31, 2015 14:05:15 GMT -5
Autochthon is just one possible subset of landrace.
It's a landrace if it a defined variety that is adapted to a specific area. It may not be native to a region. There is no time requirement other than enough time to see if it is truly adapted.
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Post by steev on May 31, 2015 20:45:08 GMT -5
It's a dirty job, but someone has to do it, so I volunteer to begin work on the forum's Cannabis landrace; send me your seeds, folks. What with the extensive testing required, this could be a life-time's work, but I'll try to keep you posted, when I'm not looking for munchies. "Autochthon", now there's a word I'll prolly not be able to spell, once this project gets rolling.
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Post by templeton on May 31, 2015 22:22:52 GMT -5
It's a dirty job, but someone has to do it, so I volunteer to begin work on the forum's Cannabis landrace; send me your seeds, folks. What with the extensive testing required, this could be a life-time's work, but I'll try to keep you posted, when I'm not looking for munchies. "Autochthon", now there's a word I'll prolly not be able to spell, once this project gets rolling. Not sure that SH contributions would make it to you, Steev, unless of course it was forwarded via Mexico, in which case by all accounts it will just mooch across the border...We are aiming for a great rope-making fiber plant for farm use, aren't we? T |
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Post by oldmobie on May 31, 2015 22:31:24 GMT -5
It's a dirty job, but someone has to do it, so I volunteer to begin work on the forum's Cannabis landrace; send me your seeds, folks. What with the extensive testing required, this could be a life-time's work, but I'll try to keep you posted, when I'm not looking for munchies. "Autochthon", now there's a word I'll prolly not be able to spell, once this project gets rolling. Not sure that SH contributions would make it to you, Steev, unless of course it was forwarded via Mexico, in which case by all accounts it will just mooch across the border...We are aiming for a great rope-making fiber plant for farm use, aren't we? T I'm sure he's only after the fibers for rope making. All the psychoactive portions should be kept out of the wrong hands. I reccomend burning. |
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