Can anyone help me understand the concept of hybrid?

Discussion in 'Gardening & Plant Propagation' started by -, Jul 19, 2003.

  1. Guest

    I'm not after a real technical explanation--but I am curious why, if I harvest seeds from a "hybrid" tomato which I like--such as the Santa Sweet grape tomatoes which came around this year--I am unlikely to get a similar tomato when I plant it next year. What am I likely to get? (I probably should have paid more attention in high school biology. . .)
     
  2. culpeper

    culpeper Well-Known Member

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    Seeds contain all the genetic material of the plant, dating back from the Year Dot. Those 'older' genes are more dominant than the newly introduced genes, which may not be reproduced in the 'new' plant. That's why, when you try to grow a lemon tree from the seeds of your fantastic modern lemons, you'll usually end up with a monstrosity, covered in thorns, and with inedible fruit like marbles. Also, with the advances in botanical science, it's possible to make seeds of a hybid sterile, so they won't reproduce. Such viable seed as you get, will have the genes of the original, back-to-basics plant.
     

  3. Idahofarmergal

    Idahofarmergal Well-Known Member

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    This is how I understand it: A hybrid is a cross between two genetically stable varieties (think "shepard" and "labrador retriever"). A first generation hybrid (the first crossing between two genetically stable varieties) results in uniform, vigorous hybrid plants (think a really awesome mutt with no hip dysplasia). But, when you cross a hybrid with a hybrid (like mating two mutts), you will get an assortment of different types of plants because the variety of genetics and other factors (recessive genes, etc.) that will make this explanation scientific mumbo jumbo. You can expect about 25% of the hybrid-hybrid cross to be truly amazing plants, about 50% to be similar to the parents of the hybrid, and about 25% to be really terrible plants. So, you can save seeds from hybrids if you are aware of this and are willing to cull the bad ones. You can breed back to close to the original parent plants genetics in a few generations if you know what to select for. Interestingly, you should not save seed from that really awesome 25% as their genetics are likely to be rather unstable and they won't breed true to type. You'll get really weird plants from them.
    Terminator seed technology has not yet been used on home garden vegetable varieties in this country. It is used for much bigger dollar items such as field corn and soybeans. If you order seeds from a reputable seed company that has taken the "Safe Seed Pledge" you will not have to worry about that or GMO's.
     
  4. Paquebot

    Paquebot Well-Known Member

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    Since the original question asked about Santa Sweet F1, the originator of that variety says that 99% of the F2s will bear true to the parent plant. The other 1% will produce a smaller round fruit And that's a lot better odds than many of the so-called heirloom tomato varieties which may have been developed 60-70 years ago. Culpepper's comments and subsequent mention of modified genes has no bearing whatsoever on Santa Sweet F1 nor any other tomato variety currently available.

    Martin
     
  5. becauseHElives

    becauseHElives Member

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    I don't know anything about hybrid seeds. But...I just read a bit a go that heirloom seeds (plants) resist disease and pests, and produce better than hybrid. Is this true? I read this on an heirloom seed site~not sure if is was a marketing ploy.
    Why would a person choose to use heirloom seeds over hybrid, or vice versa?
    Thanks
     
  6. Paquebot

    Paquebot Well-Known Member

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    Virtually every variety of vegetable available was hybridized many years ago for two qualities, production and disease resistance. Since this thread started with tomatoes, I will remain with them. 95% of all tomato varieties, however old, are hybrids. The remaining 5% are mutants from the other 95%. Originally, almost every tomato variety was the target for all sorts of diseases. By crossing with stronger plants, disease resistance was bred into the varieties. Case in point. The area where I live had a tomato cannery in the 1930s and '40s. So important was it that there were several times when all children were dismissed from school to pick the tomatoes following an early frost. But then a blight moved into the area and decimated the tomato crops. Horticulturists at the University of Wisconsin worked long and hard to develop a tomato resistant to blight. Eventually, the famous "heirloom" Wisconsin 55 resulted. The rugged Rutgers was developed by Campbell Soup Co. in 1928 from a cross using Marglobe and JTD and further refined by Rutgers University in 1943, again by crossing with disease-resistant varieties.

    On the opposite pole are some of the better old varieties which are absolute wimps but preserved as is because they are so good. If you can get one healthy Kellogg's Breakfast to the garden from 10 seeds, you are lucky. Then to have that seedling survive is even more luck than skill. But the harvest is worth the near total lack of any disease resistance in that variety. Many such varieties of tomatoes have been left that way since any crossing reduces the quality or taste of the fruit.

    So, to answer the question about heirlooms being hardier, it is often true since many were created to be hardier. To say that they are hardier than hybirds is 100% false since every single one of them WAS a hybrid at one point in time. For that very reason, you may plant 100 seeds of a certain variety and one or two may produce something quite different.

    It still tickles me when I hear someone say that they will not grow any hybrids in their garden. Such a garden would be the easiest to maintain as there'd be absolutely nothing in it!

    Martin
     
  7. pepper

    pepper Well-Known Member

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    M~i~ss~i~ss~i~pp~i !
    oh mr. martin if i only could have had you there at the organic growers conference when i got into a 'disscussion' with one of our state representatives on how 'healthy' hybrids vs. 'heirlooms' were!

    she seemed to believe that hybrids had lower nutritional value because they were all sterile!, she also went on about how some were even harmful to eat no less. *sigh* i tried my best to give her a little botanical science lesson but she had ignored others better than i for years , so it was to no avail. she claimed her main source of info as mr. Whealy founder of the seed savers exch.

    i'm sure my eyes googling in wonder at her mumbo jumbo talk did not help my cause, but at 2 of the sychophant types she had hanging on talked to me later when she was not around to ask more questions, so it was not a hopeless cause.

    they at least saw the logic of plant breeding & not spontainiously appering in the garden as edibles!
     
  8. Guest

    Paquebot is right. Since it's an F1, I would tell you to experiment and save a small batch of seeds and plant them next year away from your other tomato varieties and see what you get. You should be very pleased with the results.

    Friends of mine who had family in the ag business used to experiment alot with F1s and had tremendous success with 2nd and even multi-year plantings of saved seeds.

    I remember them laughing especially over some of their follow-up year F1 cantaloupes -- great melons that had acclimated well on the coast but it was a variety unknown.

    Just as an aside, it's also fun to grow some of the experimentals the seed companies are developing and participate in their tests. We always had fun with that. Our plots weren't big enough to be part of the official testing (we were on suburban lots) but our ag friends would give us handfuls of test seeds for us to play with. They never had names, just numbers. (This was Burpee before the big corporate buyout).

    If you ever want to do that, just contact the bigger seed companies like Stokes, Park, Johnny's, any who are actively involved in development of new varieties -- they're usually happy to let you tag along with the big boys. Sometimes Johnny's will even put out an invitation to participate in their catalog.
    BW
     
  9. Sedition

    Sedition Well-Known Member

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    I’ve never found Kent Whealy to make asinine statements like “hybrids are sterile” or harmful to eat. My understanding is that he does feel that heirlooms are healthier, and I think that is because he believes selecting for hybrid vigor selects against nutritional value. In other words, we select most fruits based mostly on sugar content and yield, because they taste better and are easier to grow – but they loose the “bitter” taste, which is associated with highly nutritious foods. The nutritionist sounds like she’s Berkley educated, and has learned to drop names to try and support her outlandish statements. You can’t win arguments with folk like this, they are fanatical and not open to reason.

    Paquebot – I’ve got some questions. The first is about the history of hybridization. Now, I know that the bulk of commercial crops and most garden crops were hybridized after the process, based on the “newly” found work of Gregor Mendel, was formalized in the mid-20’s. Tomatoes in particular were subjected to heavy hybridization, probably the 2nd most hybridized crop after corn. But, what about varieties like the Brandywine family, which dates back to the 1850’s – well before hybridization? Wouldn’t any tomatoes selected from this or the other “ancient line” OP families would by definition have innate disease resistance, not hybridized?

    Also, I’m curious what you know about the “true” Grape Tomato (not the often confused Cherry tomatoes)? Is it not still pretty much the wild tomato plant? Great disease resistant, early fruit, and just barely more sweet tasting than Huckleberry Tomato. But with low yield, and a rather sour taste.

    And I sure can grow a garden with absolutely ZERO hybrids in it. Easy as pie. I’ll plant garlic, shallots, Jerusalem artichoke, potatoes, rhubarb, alpine strawberry… Ok, I know what you are going to say. Even cloning plants are based originally on hybrids (except non-seeding plants like garlic). Well, that is somewhat true, but is also seems we are getting into “Clintonese” to accept your definition that all plants are hybrid.

    The common definition of hybridization is the “mechanical, sexual cross pollination of two dissimilar plants of the same species, for the express purpose of producing Hybrid Vigor”. As you stated with your hybrid analogy, nearly all plants are hybrids, which is somewhat true. But your definition is closer to the “sexual cross pollination of two separate plants.” To use your definition, each one of us as a human being is actually a Hybrid Animal – as cross of two “separate” parents. While the accepted hybridization definition limits hybrid animals to creatures such as the Mule, or better yet, the cross of a Cocker Spaniel and a Poodle – the infamous Cockapoo.

    I’m not really trying to argue. It is just that your statements seem to be using a loose definition of accepted horticultural science, rather than the accepted tenants. I have trouble changing my own opinions without a good method of reasoning to back them up, and I am curious as to the what your opinions are based on?
     
  10. Rebekah

    Rebekah Active Member

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    It used to be that plant breeders stabilized their hybrids so that they would come true to seed, before releasing them to the public. Read some of Luther Burbank's writings for more about this, they are a wealth of information! This is where we got our open pollinated pants from; they were hybrids that had been bred until they were pretty consistent. In order to keep OP varieties that way, seed savers need to cull out the plants that are not true to the variety, or the consistency will be lost.

    This can still be done today, but it takes a lot of work, a lot of time, and a lot of money. With consumer demand changing so quickly and people who (for the most part) don't care if the seeds comes true or not, and the proprietary control over a hybrid, there just isn't as much motivation to do it anymore.
     
  11. Paquebot

    Paquebot Well-Known Member

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    I'll quickly point out some inaccuracies concerning some statements about tomatoes. Development and hybridization was going on well over 200 years ago. The only current variety which may date back to the time when Thomas Jefferson was toying with crossing them would be Red Pear. The first SMOOTH red tomato was not released until around 1860 and that was Trophy. Red Brandywine came out in 1895, not 1885 as erroneously reported in some writings. Also, no variety, hybrid or otherwise, is totally resistant to any disease no matter what seed salesmen would tell you.

    The mention of a mule was made to point out one of very few sterile hybrids and to debunk the statement that hybrids produce only sterile seeds. Cockapoos are just like any other hybrid unless there has been a complete split in the canine family that I had not heard of!

    Yes, you could have potatoes in your garden which are not hybrids but you'd have to search deep into South America to find the seed and you'd not eat very well from the resultant harvest. If you look at the history of every potato variety, they were "developed" somewhere. They weren't the result of some expedition deep into the Amazon! The latest popular potato is Yukon Gold. That was developed by Canadian researchers barely 40 years ago.

    Even the mentioned rhubarb has been tinkered with to create better varieties than what existed somewhere as a wild plant at one time. Any plant which produces a flower and seed can and has been toyed with over the ages, either by Man's hand or Mother Nature. We'd have quite a time trying to live as hunter-gatherers. Hybridization began when Man first starting planting seeds instead of just eating them. One of the few varieties which still exist in a wild form is elephant garlic and even that is considerably different than what we now grow in our gardens.

    Martin
     
  12. pepper

    pepper Well-Known Member

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    M~i~ss~i~ss~i~pp~i !
    my dear state representative was definitely 'educated' mr.sedition. but not in any type of science or logic that 's for sure. i also told the dear lady that i had never read anything by mr. whealy that would make me think he was ignorant of how his favorite heirlooms came to be. but you are right she was whaked & could not listen with an open mind to a different view. but since she was in a position of power i felt compelled to attempt a little education....*sigh*

    granted some heirlooms are sports that were bred back to the original sport &/or culled of undesired traits. but the majority came from a farmer observing her beets were bigger but the neighbor had a more marketable blood red colour so she gets to work on crossing the best specimins of her crop with the neighbors crop!

    mr. mendals work was a great help in education & scientific orginization, but he was by no means the first to hybridize or breed plants!.
    every region & many families had at least one 'famous' type of beet-cabbage-turnip-carrot-barley-rye, due to growing conditions, selection and breeding for the locally desirable traits. [drought tolerent,cold soil tolerant,hulless,etc.]
    many people smuggled ,at risk to their lives , 'famed' seed from one area/state/nation/ to another for profit.

    i have had plenty of neighbors who are illiterate [i don't mean didn't attend college, i mean illiterate, this is mississippi.] but know how to grow some great tomatoes from their own seed. anyone who is interested & obsevant with their plants can educate themselves on how to hybridize and select for desirable traits in plants.
    it is my understanding that brandywine tom. has good fruit size & disease resistance in the midwest, but down here i feel real proud when i get more than 3 fruit from a vine! taste reigns supreme in the brandy genetics i do belive.
     
  13. Sedition

    Sedition Well-Known Member

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    What it really comes down to I think, is that I strongly disagree with the use of the term “hybrid” where it does not agree with the accepted scientific definition. The technical meaning of hybrid is, “an offspring of genetically dissimilar parents or stock; especially offspring produced by breeding plants or animals of different varieties or breeds or species.”

    In terms of what a hybrid is, when marrying stable identical species to itself, even if both parents are a hybrid, the offspring would not be. That is because the parents must be dissimilar for the offspring to be a hybrid plant. In other words, the popular opinion of most of the organic growing crowd would be that a hybrid is any plant which exhibits hybrid vigor and does not breed true to type. This is because recessive traits are replaced with superior dominant genes.

    The dreaded cockapoo is an example of a hybrid. When you mate two cockapoo’s, the offspring are an oddball mix of Cocker Spaniel and Poodle. Some have curly hair, while others are long and straight. They did not breed true to type, and as such, the cockapoo is a hybrid. Two Poodles will however have another Poodle as an offspring. But the Poodle itself was a hybrid at one time, but by breeding many successive generations, the animal itself took on it’s own, distinct traits. Now, the Poodle, like any stable open-pollinated plant, is not a hybrid. Open pollinated basically means, “breeds true to type”.

    I can understand your point that many garden varieties are originally from hybrid stock. Although I’ll be honest, it is a challenge to my understanding of the history or horticulture to say that tomatoes were being actively hybridized 200 years ago. Can you point me to someplace where I can better read up about this?

    I know that you’re an alium pro as well as tomatoes. Is there a garlic variety that is a hybrid? I’m no pro myself, but my understanding is that not only is the land-race which cultivated garlic evolved from extinct, but modern horticulturalists are still puzzled over how so many different varieties were brought from it. Also, I’ve never grown elephant garlic, but I understand that it is a bulbing leek. Leeks are about the easiest alliums to gather true to type seed from, so does the elephant garlic not set fertile seed heads?
     
  14. Guest

    http://lamar.colostate.edu/~samcox/Tomato.html

    http://search.csmonitor.com/durable/2000/04/05/p12s2.htm

    http://plantsdatabase.com/go/55019/
     
  15. Paquebot

    Paquebot Well-Known Member

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    Hmmmmmmm! Elephant garlic sets viable seed in addition to cloves and corms? I think that I must fly to Spain and check out the reproduction habits of Los Mols Wild Leek!

    And all of our giant tomatoes came from the crosses of tiny little afterthought fruits of 7 or 8 perennial wild things in the length of South America? Even now, there may be yet one more added with one or more possibly distinct wild strains from the Galapagos being studied. Entire original wild populations of tomatoes were never much bigger than a marble. Cross and back-cross and we end up with 5# Delicious or Big Zac or but a puny 2# Omar's Lebanese. Those varieties didn't fall out of the sky or discovered growing in a compost pile, they were created by Man using the 24 chromosones which all of the original varieties contain. Disregarding Mother Nature's experiments with chance mutants, just using the original 7 or 8 known wild varieties, the possibilities are 24 to the 24th power compounded to 24 to the 24th power for each subsequent result and so on. And that would only involve 2 compatible species. And tomatoes are simple as everything results in a seed-filled fruit of differing appearance but recognizable as a tomato. And when you finally sort that out, figure out how kohlrabi, cabbage, cauliflower, and broccoli are the same plant but a few chromosones different.

    Martin
     
  16. Sedition

    Sedition Well-Known Member

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    So, is that a "yes they do" or a "no they don't" to my question?

    And you are exactly right on the tomatoes. Open-pollinated plants are often created by man, just like the entire motley brassica family. By selecting for a trait and in-breeding the variety, instead of hybridizing, you can end up with an entirely new variety (or even plant!) over the course of dozens or hundreds of generations.

    The difference between open pollinated varieties and a hybrid, is that with the hybrids the “weak” traits of the each variety have been somewhat replaced by the “strong” traits of the other variety. This is what hybrid vigor is. You can do the same with open pollinated inbreeding, but it takes many more generations to accomplish.
     
  17. Paquebot

    Paquebot Well-Known Member

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    Allium ampeloprasum can and does reproduce from seed and has become naturalized on many old homesteads throughout the SE and Atlantic Seaboard states.

    Martin
     
  18. Sedition

    Sedition Well-Known Member

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    Thank you. I'll make sure and avoid planting it then. I've grown King Richard leeks as both a perennial and from collected seed for years, and I'd hate to cross them. Aside from my grandmother's rhubarb I started growing when I was a young child, my leeks are my longest personally propogated plant.
     
  19. Paquebot

    Paquebot Well-Known Member

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    Ah, but you can plant both. Don't allow the elephant garlic to make a seed head. Elephant garlic is grown for the large cloves that it produces. In order to get them, the seed stalk is cut off as soon as it appears. Otherwise most of the energy goes into making a seed head while the underground growth would consist of 3 or 4 loose cloves not much larger than garlic would produce.

    King Richard is indeed a good variety to grow for the stems. My variety is simply "Por", probably similar to Varna. (Por being Cesky for leek and I got it from the Bohemian part of what is now the Czech Republic.) Very tall and slim and grown more for the long delicate leaves than for the stems.

    Martin
     
  20. Guest

    Hybrids come from a cross of two inbred lines. Each line has a genetic makeup where the given members are very similar. By crossing these lines expected phenotypes(physical charateristics) are known such crossing a dwarf wheat with a high yielding. The resulting hybrid is dwarf and heavy yielding. Thes offspring of this generation could take its height gene from either inbred and the same for the yielding qualities.

    I think everyone is forgetting that outcrossing is not hybridization. The key to hybridization is that the parents are inbred with genetic uniformity that is not as narrow as cloning, i.e. the inidividuals are not clones.