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Post by oxbowfarm on Nov 29, 2011 15:28:10 GMT -5
A commercial hybrid is a cross between two strongly inbred lines.In the most extreme case it's a cross between two lines that are 100% homozygote for all the genes. I think you are giving them to much credit, I'd bet they are only as inbred as they absolutely have to be to get the minimum desired result. Certainly not anywhere near 100% homozygous. I personally think commercial hybrids are perfectly acceptable parents for a homegrown variety or landrace, certainly if you are starting with a hybrid that is broadly adapted enough to produce seed in your location then you've got a good chance that the offspring will as well. Joseph has made some good points about the cytoplasmic male sterility issue however, I am not certain it matters for every crop. I still think a blanket anti-hybrid seed saving position is incorrect.
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Post by nuts on Nov 29, 2011 16:50:24 GMT -5
A commercial hybrid is a cross between two strongly inbred lines.In the most extreme case it's a cross between two lines that are 100% homozygote for all the genes. I think you are giving them to much credit, I'd bet they are only as inbred as they absolutely have to be to get the minimum desired result. Certainly not anywhere near 100% homozygous. I personally think commercial hybrids are perfectly acceptable parents for a homegrown variety or landrace, certainly if you are starting with a hybrid that is broadly adapted enough to produce seed in your location then you've got a good chance that the offspring will as well. Joseph has made some good points about the cytoplasmic male sterility issue however, I am not certain it matters for every crop. I still think a blanket anti-hybrid seed saving position is incorrect. If you're interested,look for doubled haploids.(there is a thread about it somewhere on this board). This technique results in 100% monozygote individuals. I agree that you must not be dogmatic about hybrids.By hybridisation you can extract genetic material from commercial hybrids. They are in general not very good material,because of their instability and because of their highly inbred origin,but you CAN do something with them. For landraces you have to take the risk that a selfing commercial hybrid will produce mostly rubbish,so I doubt if it's a good idea to incorporate a commercial hybrid in a landrace.Be sure you know what you're doing, Maybe some hybrids are less evil than others,find it out first. For landraces you better incorporate the ancestors of the hybrid than the hybrid itself. And indeed you must beware of all kind of lethal or sterilising genes,an other innovation that you'll find more and more often in commercial hybrid seed.
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Post by PapaVic on Nov 29, 2011 17:52:59 GMT -5
With regard to the last several posts in this thread, there have some very correct things said, and some very incorrect things said about modern hybrids.
There are so many hybrid tomatoes, for example, where the two parents are so nearly identical that the F2 progeny will be impossible to distinguish from one another by eyesight alone, unless the viewer is a very astute grower who happens to be intimately familiar with the two breeding lines that were inputs to the cross.
I could cite numerous examples. Here's one: Carolina Gold. The two parents are nearly identical both by sight and by heritage. Why then create a hybrid from the two parents? Well because one parent lends greater size and the other lends greater crack and weather check resistance basically. They both come from basically the same long, long lines of multiple inputs, including Mountain Gold, a previous open pollinated commercial release by the same breeder, and which is hardly distinguishable from the hybrid Carolina Gold. So why then grow the hybrid Carolina Gold rather than the open pollinated Mountain Gold? Well because Mountain Gold is susceptible to Gray Wall (a disorder common to yellow tomatoes) and Carolina Gold is resistant to Gray Wall (as are both its parents).
Point here is that 1) if you grow out Carolina Gold F2, I doubt you'd be able to distinguish much difference in the progeny unless some cracked and checked more than others, and 2) you'd probably get a "grex" of yellow (actually tangerine) tomatoes superior to any previous open pollinated yellow (or tangerine gene) tomato that was or is available on the market (such as Jubilee or Mountain Gold, both of which continue to be available and both of which are inputs into the breeding lines NC-1Y and NC-2Y that comprise the hybrid Carolina Gold).
And that is just one example of why I said earlier today I'd rather use hybrids to move forward than to beat my head against THE WALL. But that's just me.
Post script: There are many more example I could give of hybrid tomatoes where the two inbred parent lines are so similar in appearance that you could not tell the F2 progeny apart. Then there are cases where the differences would appear very slight to the casual viewer ... like one parent has jointed pedicels and the other parent has jointless pedicels so 1/4 or the F2 progeny will have jointless pedicels, for example.
I think this is why so many people who grow tomatoes or concentrate on growing only tomatoes think the seed companies are marketing stable varieties as "hybrids" just to keep people from growing the F2 seeds out. I personally don't think that is the case. I personally think most professional breeders are ethical individuals who spend many many long hours for many many long years developing highly specialized inbred parent lines that carry specific traits (such as specific disease resistances, color traits, genetically encoded nutritional traits, etc.) that are then used to combine those traits into viable hybrid germplasm that delivers superior results.
For example: in order to get beta carotene, and even more critical to get high-delta carotene, in a tomato, you have to have specific genes in one of the parent lines and then introduce specific genes from another parent line in order for the one set of genes to work on the other set of genes to convert lycopene into beta- or delta-carotene. Yes, you can capture the gene combos in the progeny of the hybrid, but first you got to select the correct parents to create the initial hybrid (one input is L. hirsutum in origin).
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Post by PapaVic on Nov 29, 2011 18:31:32 GMT -5
Here's another issue that I think is misunderstood or misrepresented: "lethal or sterilizing genes."
Again, I'll use tomatoes for the example. Yes, there are genes in some tomato lines that cause male sterility. That would mean that a plant with the male-sterile gene(s) will not produce viable pollen to self-pollinate the female components of the perfect flower (tomatoes have perfect flowers, containing both male and female parts in the same blossom).
An example of a hybrid tomato that carries a male sterility gene (ms-10) is Plum Regal, a very good determinate plum saladette that is tomato spot wilt virus resistant (TSWV) and Late Blight resistant. One parent to the hybrid contributes the ms-10 male sterility gene. The gene is tied to another gene, in this instance, called green stem (aa) which is a "marker gene." Yes, the dreaded marker gene!
But is it so terrible? No, because with the aa green stem marker tied to ms-10 male sterility, one can spot the sterile progeny in the seedling stage due to the glassy green stems devoid of anthocyanin. So, you know pretty immediately which plants are sterile.
Well, they're not really completely sterile, just male sterile - they don't produce viable pollen. Is that a horrible thing? No, because you can use the male sterile plants to RECEIVE pollen from other parent lines. And they can receive and use the pollen without you having to emasculate the flowers, right? Oh boy! That eliminates a whole lot of tedious, time consuming, meticulous hand work. Yes, now all you have to do is collect pollen from another parent line, and apply the pollen to the exherted stigmas on the male sterile plants. Voila! more hybrids.
And since ms-10 male sterility and aa green stem marker both are recessive and linked to each other in this case there will be only 25% of the total F2 progeny to express both traits in recombination.
Why do I defend hybrids like Plum Regal? Well because when the two parents of the cultivar are combined, the resulting hybrid carries resistance (attained in some cases separately from each parent) to TSWV, late blight, gray wall, cracking, and intermediate resistance to bacterial spot. The hybrid also carries high crimson gene resulting in increased vitamin content in the fruit. We all realize of course that if tomatoes such as these did not exist, there would be many people in many countries who would not have the nutritional benefit from the fruit of these plants because the plants would not survive to bear fruit due to climatic and disease pressures.
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Post by grunt on Nov 29, 2011 19:17:32 GMT -5
Thank you Bill. I have to admit I was thinking primarily of tomatoes with my comments on hybrids. I hadn't considered the cytoplasmic male sterility issue = I saw "hybrids" and replied, with primarily tomatoes in mind.
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Post by nuts on Nov 30, 2011 16:57:23 GMT -5
Thanks papavic for all those clarification. You explained that most commercial hybrid tomatoes were from a practical point of view close to stable varieties. That you can find genes in hybrides that you can't find elsewhere. That male sterility is very usefull (as I understand for producing tomatoe "hybrid" seed) That markers are very usefull for getting rid of the male sterility. That some results you can only get with hybridisation. That plantbreeders are ethic persons That hybrids contributed to human well being.
I don't agree with all of it. And what's true for tomatoes is not nessecerily true for other crops I was rather thinking of corn and such. I'm not an ayatolla anti-hybrid.A headbanger??...maybe My jihad is directed against seedcompanies. ;D ;D The systematic use of hybrids is just one of the symptoms of the evil
A small comment The male sterility thing seems really crucial for producing commercial tomatoe hybrid seed. And I don't see how a breeder. can do without except by emaculating hundreds of flowers by hand. So if a hybrid don't have this gene there can be doubt if he used the typical procedure for producing commercial hybrid seed. Indeed maybe he call it hybrid for the reason you mentioned or,I think it can be because "hybrid" sounds so innovative.Of course he can change his mind if he becomes aware that many of his potential clients are suspicious about hybrids. I don't see anything unethical in that,he is not a lyer . because every plant is a hybrid.
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Post by PapaVic on Nov 30, 2011 18:27:25 GMT -5
Nuts, I don't think you and I are very far apart on what's "good" or what's "bad" about seed companies and corporate greed or corporate self-preservation or all that's involved in pleasing the shareholders or satisfying the CEO's insatiable need for bonuses, whatever else along those lines.
I do think we are way far apart on our individual understanding of a few of the issues or some of the specifics. But yes, I know the extent of Roundup Ready grain cropping especially in corn and soybeans. After all I live right smack dab in the middle of it. And I understand that when a neighbor is growing Roundup Ready corn or beans, and spraying his field borders, turn rows, fence lines and ditch tops with Roundup, it's awful hard to avoid employing Roundup Ready seed in your nearby fields. And yes, I know even if you are able to resist using Roundup Ready seed, you still get the pollen drift that contaminates your seed and makes you liable for what I too consider unnecessary, excessive, oppressive and unethical legal abuse by Monsanto or whomever else. Yes we can agree on lots of things like that.
And the use of male sterile tomato lines for breeding hybrids is very limited really. But when it is used, it does save a hell of a lot of time and labor. You know how expensive hybrid tomato seed has become, especially that which is produced in greenhouses or in countries where labor costs are relatively high. I was just giving an example of how something that has been demonized actually can be a benefit. Just an example, not an excuse for corporate abuses.
And while we are on corporate abuses, how lucky are we not to be poor barefoot serfs in some southeast Asian backwater slogging through malarial climates producing seed for hobby gardeners in the richer nations? I wonder sometimes how we can relax in front of a computer and carry on like spoiled children about how miserable life has become for us due to mental anguish caused by the corporations that feed, clothe, medicate, shelter, employ, and enrich us Americans.
But back to plant breeders who work for the corporations ... hey, I can hardly blame them after attaining advanced degrees in their chosen field when they hire on to a company that provides the labs and facilities in whch they can pursue their careers in horticulture.
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Post by jonnyyuma on Nov 30, 2011 19:58:45 GMT -5
Good point Papavic. It is interesting that markers have been around forever for phenotypic traits. It is only in the last 30 years, and more importantly the last 10-15 years that they have become commonplace, and cheap enough, in laboratories and not the field. It is essentially the same process and same idea just one appears on the plant at a certain maturity stage and the other marker appears in the lab on a data printout or gel. Genetic markers and phenotypic markers work the same way and suffer from the same issues (i.e. crossing over and not working). Thanks Jonny
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Post by jonnyyuma on Nov 30, 2011 20:54:01 GMT -5
Personally I am not a big population improvement person. I much prefer pedigree type breeding and single plant selections verse adding a bunch of stuff together and letting it shake out. I am not saying it is not a good way of doing things, just not my preferred way. With that said you still need hybridization to take place to get population breeding to work. If you don't have strong inter-crossing in your population, it is difficult to improve the population and you will suffer from drift badly and you may loose the diversity you set out to achieve. Being a pedigree orientated person I like commercial F1 hybrids because I can get recombinants w/o the hassle of having to make the hybrid myself.
Thanks Jonny
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Post by littleminnie on Dec 8, 2011 12:35:34 GMT -5
I hadn't noticed this thread before. I just got home from my eye exam and was going to just check email because my eye hurts. Now I have had to read this whole thread! If you don't mind going back to the original subject. (and this is going to be long) I have been hot on this topic lately! In fact I just emailed a local certified organic grower who has a large CSA farm I toured once to ask him how his conscience allows him to grow Seminis varieties. He said he had to make a living and they are reliable. He also said we all buy gas from the bad oil companies. Well we have to buy gas, we don't have to buy Seminis hybrids. Plus when you are growing to sell, and to sell certified organic at that, you have to consider what your customers expect. I get sick of farmers or markets essentially hiding things from customers. They infer everything is local for one and many farmers infer and dupe IMO the average customer into thinking they use no chemicals be it herbicide or fertilizer or pesticide, when in fact they do. So customers' naivety is taken advantage of, badly. I doubt this farmers' customers, who are paying for certified organic, would appreciate the fact that he buys a lot of Seminis hybrids and so their money is going to Monsatan. A couple years ago when I my eyes were opened to all of this, I talked with some of the big seed catalog companies to ask, as many people did, for them to remove Seminis seeds. Pinetree's answer is a good example. They said they had been working with the fine people at Seminis for many years and wouldn't leave those people now. Boo hoo. I am sure they are fine now with mother Monsanto. Other companies said they couldn't find worthwhile replacements. Well Fedco has removed all of Seminis seeds and often write about it in their catalog. They say this variety is a replacement of Seminis ____ variety. Way to go Fedco. So this is my position and extent of knowledge at this time. What scares me is that I will learn more about things I believe to be safe and then realize I have been naive. It reminds me of that episode of Seinfeld when Elaine wanted the Mexican style shoes and clothes but the cashier made her angry so she shopped at the other Mexican store and at the end she found out they were both owned by the same person, Gladys Mayo. That is what i don't want to happen to me and all the people I have informed on the subject!
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Post by littleminnie on Dec 8, 2011 12:39:26 GMT -5
Side point: when you bring this subject up on less informed forums you get many people who don't understand the difference between having a moral issue with buying Seminis hybrids and the money going to Monsanto vs buying GE seed. Most people are afraid of buying GE seed and think they have to avoid certain companies to be "safe." We are not talking about GE seeds, only giving money to the company who makes many of them. Customers are very confused about this and there is a great deal of inaccuracy online, like this link: www.garden-of-eatin.com/how-to-avoid-monsanto/
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Post by paquebot on Dec 8, 2011 16:06:28 GMT -5
Well, just about every vegetable we grow has been genetically engineered. There aren't many whose genes have not been manipulated by Man. Thus using GE as a scare tactic is totally wrong and merely a sales gimmick or some ulterior motive. This is especially true since the GMO vegetable thing has flown about like a lead balloon. Those who use the non-GMO vegetable seed line to promote their products are unable to point to which GMO vegetable seeds they are supposedly protecting us from. May as well advertise that all of a company's seeds are produced on Earth. That would be just as meaningful as advertising all non-GMO vegetable seed.
Martin
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Post by jonnyyuma on Dec 10, 2011 23:26:48 GMT -5
Hello Minnie, I find it interesting that Fedco has removed Seminis varieties from their catalog, but seem to have no problem selling varieties from Syngenta (the worlds second largest GMO company and marketer of some pretty strong chemicals as well). Fedco has made it a point of marketing to their customers that they do not carry Seminis. Is this a dishonest position to take? I don't know, it is their choice to make, but it brings me back to the same question. Is it the act or the actor? It would seem to me that it is the actor and not the act as Fedco carries seed from Rogers (Syngenta owned) who has marketed BT sweet corn for at least 10 years if not 15.
I am interested in what others thoughts/comments are as well. Thanks again to all!
Jonny
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Post by Joseph Lofthouse on Dec 10, 2011 23:57:16 GMT -5
I have adapted the world view that I am going to source ALL of my seeds, for the rest of my life, from small growers. Fedco, Syngenta, and Monsanto are all synonyms to me: Big corporations that I believe cause harm to me, my family, and my biosphere. I call them The Company in day-to-day conversation so that I don't single out any one corporation, and also so that I don't inadvertently forget to include one.
It is time consuming and inconvenient to avoid buying from The Company, but the seeds sure seem to grow better when they have been raised by human beings that know each parent plant as an individual.
I haven't singled out the seed companies for special treatment. For example, all of the electricity for my home is generated by solar panels so that I don't have to make monthly payments to The Company. It will be a very happy day for me when i can grow all of my own food and don't have to get any from The Company. I guess I could do it the same way I did with seeds. Just make a decision to stop supporting those whom I believe are harming me and make whatever adjustments are necessary. It's very easy for example to buy non-USDA meat on the black market.
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Post by keen101 (Biolumo / Andrew B.) on Dec 12, 2011 0:20:14 GMT -5
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