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Your comment on GM crops is technically correct but also misleading. Most crops are already grown from hybrid seeds. For reasons of genetics, hybrid seeds can

Your comment on GM crops is technically correct but also misleading. Most crops are already grown from hybrid seeds. For reasons of genetics, hybrid seeds cannot be reused in the next season. It's also quite a time-consuming process to reuse seeds, which makes the whole process less cost effective anyway. GM crops have not had a significant effect on this issue.

h0l0cube 7y ago
> For reasons of genetics, hybrid seeds cannot be reused in the next season. Can you provide supporting evidence/materials to back this claim?
- metiscus 7y ago
  Depending on the plant, you'll get either of the two species used to make the hybrid instead of the hybrid itself.
  - h0l0cube 7y ago
    Thank you, and excuse my naivete here. So what makes the hybrid route the optimal way to produce these GM plants, rather than cross-breeding in a way that survives reproduction? Do we know GM crops to always be hybrids of this nature?
    - LennyWhiteJr 7y ago
      Hybrid vigor https://en.wikipedia.org/wiki/Heterosis https://en.wikipedia.org/wiki/Heterosis It lets you create a sort of super crop... but it only works for a single generation. ‾\_(ツ)_/‾
    - galangalalgol 7y ago
      Also, as someone said above, this predates GM, its unrelated.
      - deleted 7y ago
        [deleted]
    - samvher 7y ago
      The way I understand it (I took a course in this 5 years or so ago but might not remember correctly) it's a matter of ease of matching up certain chromosomes. Like people, plants tend to have chromosomes in multiples (though not necessarily 2). From one generation to the next, for a given set of chromosomes, a parent only passes half on to the child, and this is pretty much random. That means that for a plant breeder it's very undesirable to have parents with genetic diversity: this diversity results in randomness (unpredictability) in the offspring. BUT you don't want offspring that has identical copies for all these chromosomes because those are not strong genotypes (this is where the hybrid vigor comes in, you want plants with diverse chromosomes). The solution that plant breeders have found is that you take parents which have copied chromosomes, but you take 2 different parents and you control who the parents are. That way the offspring gets a mix, but the content of that mix is highly predictable. Some side issues are that the parents are only suitable for breeding (they don't have strong genotypes themselves) and that if you take this offspring and mix them again you get a genetic shuffle which reintroduces unpredictability. This second generation will also perform very poorly, or at least unpredictably. For seed companies you can tell that this is attractive in 2 ways: they can produce quality seed relatively easily, and the farmer always needs to buy the seed that they use for production because the farmer does not have the parent plants and the second generation is unusable.
    - mcv 7y ago
      It's not just GM plants. In fact, the GM crops might not even be hybrids at all (I don't really know). But many fruits that we love, like most citrus fruits, as well as bananas, are the result of cross-breeding between different species. Why is this optimal? Well, I guess it isn't always. I'm willing to bet there are more failed hybrids than successful ones, but sometimes when you combine traits from different species, you get something that's bigger or tastier than the originals. I have no idea about other crops; I was under the impression that grain and many other common crops could be replanted, but maybe it can't.
    - bregma 7y ago
      A mule is a hybrid. It's bigger and stronger than either a donkey or a horse. It is infertile. It's the same with your garden variety hybrid corn or tomatoes. Big easily stotable and shippable product (but without flavour or desirable texture), but is infertile or doesn't breed true. Not all hybrids are infertile. Maize corn was developed from its wild progenitors through centuries of genetic modification through selective hybridization -- it is not a plant found in nature -- and that required viable offspring. The same goes for other major crops developed by scientists in the past few centuries, like potatoes, tomatoes, and peppers (interesting pattern there, they all originated in the same part of the world). It's incorrect to conflate hybridization with modern direct gene manipulation (GMO). They both have the same goal, and effectively do the same thing, but are completely different approaches. Hybridization requires the cross-breeding of unrelated varieties or species, and involves both genetic and epigenetic selection. GMO is directly splicing genes of a single organism to produce altered offspring. Don;t confuse the two.
- Metacelsus 7y ago
  Mendel's law of independent assortment.
  - Red_Leaves_Flyy 7y ago
    https://www.ndsu.edu/pubweb/~mcclean/plsc431/mendel/mendel3.htm https://www.ndsu.edu/pubweb/~mcclean/plsc431/mendel/mendel3....
- LennyWhiteJr 7y ago
  Cash crops use something known as hybrid vigor (https://en.wikipedia.org/wiki/Heterosis https://en.wikipedia.org/wiki/Heterosis) which breeds together two distinct, albeit mediocre, blends into a single offspring that is sort of like a super plant. The catch though is that it only works for a single generation, and if you were to replant the crop's offspring you would end up with a highly undesirable crop. For this reason, almost no farmers replant using their harvest. This pre-dates the use of GMO seeds. Every summer in the midwest you get armies of workers who do something called 'detasseling' where you walk through the seed fields and rip off the male genetalia of one of the two breeds, which forces the seeds to be pollinated in a specific way. The result is the seeds that are used to plant next years crop. source: I grew up on a corn farm.
  - vectorEQ 7y ago
    is this for all farms or just very large ones? i can imagine small time farmers perhaps not having such super seeds / plants?
    - stevehawk 7y ago
      It's pretty much all farms in the US, since most farms in the US are hard corn or soy farms. It's large and small. Bank owned and family owned. Everyone buys their seed every year. It's not some conspiracy, it's just better business for the farmer.
      - kls 7y ago
        Heirloom and organic farmers tend to reseed from heritage crops. I will give you they are a small subset of farming but the cross germination is having an effect on them.
    - philipov 7y ago
      The case of hybrid vigor I'm familiar with is from camels during the middle ages. One hump camels are adapted to hot desert climates, while two hump camels are adapted to cold steppe climates. This created a divide between central asia and the middle east where you would have to switch camels as you traveled. There were people who learned to crossbread the camels to create a hybrid that was stronger than either and could survive in both climates, and they began to dominate trade routes in the area. The catch was that the hybrid vigor only lasted a single generation, and if you tried to breed them again you'd get runts.
- nimbius 7y ago
  monsantos 'terminator' seed comes to mind. https://en.wikipedia.org/wiki/Genetic_use_restriction_technology https://en.wikipedia.org/wiki/Genetic_use_restriction_techno...
  - h0l0cube 7y ago
    The article doesn't specifically mention Monsanto, though I couldn't imagine them not pursuing this technology. Also, thankfully: > As of 2006, GURT seeds have not been commercialized anywhere in the world due to opposition from farmers, consumers, indigenous peoples, NGOs, and some governments. It's a common narrative that Monsanto did release crops into the wild that caused nearby farms to produce sterile crops after incidental cross-pollination. It seems like this is misinformation?
    - seattle_spring 7y ago
      It's absolutely misinformation, as is almost everything else you read on the subject of GMOs.
- xadhominemx 7y ago
  Have you tried google? This is a very basic fact about hybrid seeds.
- logfromblammo 7y ago
  F1 hybrids are the first generation (filial-1) offspring of two homozygous parents, both of which breed true for certain genetic factors. The F1 hybrid is a uniformly heterozygous cross. They will be a consistent and uniform mix of desired genetic factors, much like clones, but all siblings of parents that are themselves like clones. The F2 generation will be less consistent. The genes will recombine such that the desired high-producing mix of genes will not be present in all offspring. By the F3 generation, it will almost be back to the diversity of a genetically unmanaged population. Harvest times will spread out, such that by the time the slowest plants mature, the fastest ones may already be spoiling or eaten by birds. F2 seed can be sold and planted the next season, at a lower price, but the yield will be lower than with F1 seed. F3 seed is not economically viable to sell for planting, as the farmers that habitually save seed probably already have F3 or greater from their last crop, or an heirloom cultivar.
- Angostura 7y ago
  A lot of commercially sold seedstock is F1 hybrids https://en.wikipedia.org/wiki/F1_hybrid https://en.wikipedia.org/wiki/F1_hybrid ... first generation crosses between different parent strains. If you sow the seed from F1 hybrids (F2) they don't have a consistent phenotype

h0l0cube 7y ago

> For reasons of genetics, hybrid seeds cannot be reused in the next season. Can you provide supporting evidence/materials to back this claim?

metiscus 7y ago
Depending on the plant, you'll get either of the two species used to make the hybrid instead of the hybrid itself.
- h0l0cube 7y ago
  Thank you, and excuse my naivete here. So what makes the hybrid route the optimal way to produce these GM plants, rather than cross-breeding in a way that survives reproduction? Do we know GM crops to always be hybrids of this nature?
  - LennyWhiteJr 7y ago
    Hybrid vigor https://en.wikipedia.org/wiki/Heterosis https://en.wikipedia.org/wiki/Heterosis It lets you create a sort of super crop... but it only works for a single generation. ‾\_(ツ)_/‾
  - galangalalgol 7y ago
    Also, as someone said above, this predates GM, its unrelated.
    - deleted 7y ago
      [deleted]
  - samvher 7y ago
    The way I understand it (I took a course in this 5 years or so ago but might not remember correctly) it's a matter of ease of matching up certain chromosomes. Like people, plants tend to have chromosomes in multiples (though not necessarily 2). From one generation to the next, for a given set of chromosomes, a parent only passes half on to the child, and this is pretty much random. That means that for a plant breeder it's very undesirable to have parents with genetic diversity: this diversity results in randomness (unpredictability) in the offspring. BUT you don't want offspring that has identical copies for all these chromosomes because those are not strong genotypes (this is where the hybrid vigor comes in, you want plants with diverse chromosomes). The solution that plant breeders have found is that you take parents which have copied chromosomes, but you take 2 different parents and you control who the parents are. That way the offspring gets a mix, but the content of that mix is highly predictable. Some side issues are that the parents are only suitable for breeding (they don't have strong genotypes themselves) and that if you take this offspring and mix them again you get a genetic shuffle which reintroduces unpredictability. This second generation will also perform very poorly, or at least unpredictably. For seed companies you can tell that this is attractive in 2 ways: they can produce quality seed relatively easily, and the farmer always needs to buy the seed that they use for production because the farmer does not have the parent plants and the second generation is unusable.
  - mcv 7y ago
    It's not just GM plants. In fact, the GM crops might not even be hybrids at all (I don't really know). But many fruits that we love, like most citrus fruits, as well as bananas, are the result of cross-breeding between different species. Why is this optimal? Well, I guess it isn't always. I'm willing to bet there are more failed hybrids than successful ones, but sometimes when you combine traits from different species, you get something that's bigger or tastier than the originals. I have no idea about other crops; I was under the impression that grain and many other common crops could be replanted, but maybe it can't.
  - bregma 7y ago
    A mule is a hybrid. It's bigger and stronger than either a donkey or a horse. It is infertile. It's the same with your garden variety hybrid corn or tomatoes. Big easily stotable and shippable product (but without flavour or desirable texture), but is infertile or doesn't breed true. Not all hybrids are infertile. Maize corn was developed from its wild progenitors through centuries of genetic modification through selective hybridization -- it is not a plant found in nature -- and that required viable offspring. The same goes for other major crops developed by scientists in the past few centuries, like potatoes, tomatoes, and peppers (interesting pattern there, they all originated in the same part of the world). It's incorrect to conflate hybridization with modern direct gene manipulation (GMO). They both have the same goal, and effectively do the same thing, but are completely different approaches. Hybridization requires the cross-breeding of unrelated varieties or species, and involves both genetic and epigenetic selection. GMO is directly splicing genes of a single organism to produce altered offspring. Don;t confuse the two.
Metacelsus 7y ago
Mendel's law of independent assortment.
- Red_Leaves_Flyy 7y ago
  https://www.ndsu.edu/pubweb/~mcclean/plsc431/mendel/mendel3.htm https://www.ndsu.edu/pubweb/~mcclean/plsc431/mendel/mendel3....
LennyWhiteJr 7y ago
Cash crops use something known as hybrid vigor (https://en.wikipedia.org/wiki/Heterosis https://en.wikipedia.org/wiki/Heterosis) which breeds together two distinct, albeit mediocre, blends into a single offspring that is sort of like a super plant. The catch though is that it only works for a single generation, and if you were to replant the crop's offspring you would end up with a highly undesirable crop. For this reason, almost no farmers replant using their harvest. This pre-dates the use of GMO seeds. Every summer in the midwest you get armies of workers who do something called 'detasseling' where you walk through the seed fields and rip off the male genetalia of one of the two breeds, which forces the seeds to be pollinated in a specific way. The result is the seeds that are used to plant next years crop. source: I grew up on a corn farm.
- vectorEQ 7y ago
  is this for all farms or just very large ones? i can imagine small time farmers perhaps not having such super seeds / plants?
  - stevehawk 7y ago
    It's pretty much all farms in the US, since most farms in the US are hard corn or soy farms. It's large and small. Bank owned and family owned. Everyone buys their seed every year. It's not some conspiracy, it's just better business for the farmer.
    - kls 7y ago
      Heirloom and organic farmers tend to reseed from heritage crops. I will give you they are a small subset of farming but the cross germination is having an effect on them.
  - philipov 7y ago
    The case of hybrid vigor I'm familiar with is from camels during the middle ages. One hump camels are adapted to hot desert climates, while two hump camels are adapted to cold steppe climates. This created a divide between central asia and the middle east where you would have to switch camels as you traveled. There were people who learned to crossbread the camels to create a hybrid that was stronger than either and could survive in both climates, and they began to dominate trade routes in the area. The catch was that the hybrid vigor only lasted a single generation, and if you tried to breed them again you'd get runts.
nimbius 7y ago
monsantos 'terminator' seed comes to mind. https://en.wikipedia.org/wiki/Genetic_use_restriction_technology https://en.wikipedia.org/wiki/Genetic_use_restriction_techno...
- h0l0cube 7y ago
  The article doesn't specifically mention Monsanto, though I couldn't imagine them not pursuing this technology. Also, thankfully: > As of 2006, GURT seeds have not been commercialized anywhere in the world due to opposition from farmers, consumers, indigenous peoples, NGOs, and some governments. It's a common narrative that Monsanto did release crops into the wild that caused nearby farms to produce sterile crops after incidental cross-pollination. It seems like this is misinformation?
  - seattle_spring 7y ago
    It's absolutely misinformation, as is almost everything else you read on the subject of GMOs.
xadhominemx 7y ago
Have you tried google? This is a very basic fact about hybrid seeds.
logfromblammo 7y ago
F1 hybrids are the first generation (filial-1) offspring of two homozygous parents, both of which breed true for certain genetic factors. The F1 hybrid is a uniformly heterozygous cross. They will be a consistent and uniform mix of desired genetic factors, much like clones, but all siblings of parents that are themselves like clones. The F2 generation will be less consistent. The genes will recombine such that the desired high-producing mix of genes will not be present in all offspring. By the F3 generation, it will almost be back to the diversity of a genetically unmanaged population. Harvest times will spread out, such that by the time the slowest plants mature, the fastest ones may already be spoiling or eaten by birds. F2 seed can be sold and planted the next season, at a lower price, but the yield will be lower than with F1 seed. F3 seed is not economically viable to sell for planting, as the farmers that habitually save seed probably already have F3 or greater from their last crop, or an heirloom cultivar.
Angostura 7y ago
A lot of commercially sold seedstock is F1 hybrids https://en.wikipedia.org/wiki/F1_hybrid https://en.wikipedia.org/wiki/F1_hybrid ... first generation crosses between different parent strains. If you sow the seed from F1 hybrids (F2) they don't have a consistent phenotype