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Post by honeydew on Nov 28, 2010 10:30:05 GMT -5
This may sound like a really dumb question, but I only recently heard the term landrace, and I don't quite get what it is. I tried to look it up on the net, but I didn't even quite get the explanation.  Can someone please explain it simply? TIA Marie |
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Post by johno on Nov 28, 2010 10:46:12 GMT -5
No such thing as a dumb question.
I'm not convinced yet that I fully understand the term, either, but my working definition at present goes something like this: a variety or collection of interbreeding varieties that were developed in a specific location with selection based more or less on survival of the fittest for that location. Examples might include many traditional native varieties (which may or may not yield multiple forms of the fruit), or modern day examples by forward thinking amateur breeders like Joseph Lofthouse and others on this forum or elsewhere.
Somebody please tighten up this definition!
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Post by Alan on Nov 28, 2010 10:57:48 GMT -5
No such thing as a dumb question. I'm not convinced yet that I fully understand the term, either, but my working definition at present goes something like this: a variety or collection of interbreeding varieties that were developed in a specific location with selection based more or less on survival of the fittest for that location. Examples might include many traditional native varieties (which may or may not yield multiple forms of the fruit), or modern day examples by forward thinking amateur breeders like Joseph Lofthouse and others on this forum or elsewhere. Somebody please tighten up this definition! Johno, you essentially have the jist of it. Traditionally a landrace refers to both a type of breeding and preservation of native seed varieties. In most cultures around the world the conventional method of plant improvement involved creating a genepool of material, combining multiple varieties of one crop in the seed sack, planting them out, selecting for certain traits to be uniform such as DTM and growth habbit while still maintaining phenotypic diversity (though not always). In modern terms, most of my projects start out as genepools, grexes, or mixes of multiple varieties of one crop. After growing and selecting for those traits which perform best in my climate and reaching some apex of intergression the grex then becomes a locally adapted landrace, differing both from the original mix and from anything else out there. As an example Johno, your version of Astronomy Domine is no longer a genepool, but a landrace, differing from my own and everyone elses. Still usable in other locations around the globe, but less diverse than the first couple of generations.  |
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Post by Joseph Lofthouse on Nov 28, 2010 11:46:53 GMT -5
Here's my attempt at a definition for landrace.
A landrace is a food crop with lots of genetic diversity which contributes to it's ability to survive new pests, new diseases, or changes in cultural practices or in the environment.
In the case of mostly self-pollinating plants like peppers, tomatoes, beans, wheat, and peas a landrace may be thought of as many distinct varieties growing side by side.
In the case of out-crossing plants like cantaloupe, squash, or corn, a land-race can be thought of as an open pollinated population with tremendous genetic diversity. Many of the seeds in an out-crossing land-race end up being unique F1 hybrids.
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Post by Joseph Lofthouse on Nov 28, 2010 12:05:11 GMT -5
As an example Johno, your version of Astronomy Domine is no longer a genepool, but a landrace, differing from my own and everyone elses. Still usable in other locations around the globe, but less diverse than the first couple of generations. I'm planning on sinning if not next spring then the spring after. I'm going to add genetic material to my Astronomy Domine..... Gasp. Polluting a "pure" variety... Giggles. Sweet corn seeds from my Indian corn crosses with sweet corn are just becoming available. I figure I'll grow out and taste the offspring cobs before I add them into Astronomy Domine. Technically I already sinned by planting a Bodacious sweet corn patch only three feet away from Astronomy Domine, but that is inadvertent not deliberate so it doesn't seem like so much of a sin. And it doesn't seem like a sin to deliberately de-tassel Astronomy Domine and pollinate it with sugary enhanced pollen since (I think) I won't call that AD. |
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Post by Alan on Nov 28, 2010 13:02:58 GMT -5
the word landrace means a preservation of native varieties? Wouldnt that just be called preservation? There are both varieties preserved, and landraces by my understanding. The land races being the groupings where there is a wide expression of genetic variance, and attributes. Varieties of course being those selected down to more specific traits. And wouldnt breeding just be called breeding? Often just by trading for seed from other locations and people, and including it right into their fields along with what they all ready had. but still often being rather selective in final traits, within a range. Others by my understanding purposely left things rather diverse, and selected their crops mainly by survival, more then anything else. and those diverse groupings of trait representation being referred to as landraces. Landraces, though diverse, still represent a population which is true breeding in certain aspects; days to maturity, climatic adaptation, ect, thus I still consider them varieties, albeit in a much wider sense than a fixed variety. Yes, a landrace includes the preservation of genes otherwise not fixed in a selected variety, if you save seed you are preserving genetics as well as altering genetics, including in landrace varieties. Anytime one crop crosses with another crop and you make selections you are effectively breeding, this includes work with landraces. The status quo of plant breeding throughout the course of most of human civilization has been Landrace breeding. Grouping like types of plants of multiple varieties together and saving them together while allowing for genetic drift and saving fromt he best of each generation, ocassionally a specific selection is made and line breeding begins giving rise to a pure variety. |
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Post by Alan on Nov 28, 2010 13:06:02 GMT -5
As an example Johno, your version of Astronomy Domine is no longer a genepool, but a landrace, differing from my own and everyone elses. Still usable in other locations around the globe, but less diverse than the first couple of generations. I'm planning on sinning if not next spring then the spring after. I'm going to add genetic material to my Astronomy Domine..... Gasp. Polluting a "pure" variety... Giggles. Sweet corn seeds from my Indian corn crosses with sweet corn are just becoming available. I figure I'll grow out and taste the offspring cobs before I add them into Astronomy Domine. Technically I already sinned by planting a Bodacious sweet corn patch only three feet away from Astronomy Domine, but that is inadvertent not deliberate so it doesn't seem like so much of a sin. And it doesn't seem like a sin to deliberately de-tassel Astronomy Domine and pollinate it with sugary enhanced pollen since (I think) I won't call that AD. When it comes to seed that came from Hip-Gnosis there is no sinning or polluting, simply only expanding the exploration of both outer and inner space. Thats why I bred Astronomy Domine, so it would fall in the hands of guys like Joseph and Johno where it could evolve or be involved in the evolution of new, bio-regionally adapted, varieties, landraces, grexes. ext. |
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Post by Alan on Nov 28, 2010 13:08:01 GMT -5
Alan, can you add grex to the glossary of definitions as well please? If I understand it correctly, it is the selection of seed or genetic material before the a trial has self selected or been culled of inferior types for that region or condition? Once some generations have been selectively culled , then it evolves to being more of a landrace variety ? Sure will, gotta go to work on the barn first but thats the jist. Essentially the mixing of seeds of multiple varieties of one crop in such a way that they are bound to integress with one another. After you have selected against what you don't want but have included and selected for diverse phenotypes then you have a landrace essentially. |
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Post by Alan on Nov 28, 2010 13:09:57 GMT -5
I should include that landraces are not "static" they do evolve and you can add genetics. Regardless, over time you end up selecting based on averages due to dominant genes occuring in the landrace which may or may not represent themselves visually.
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Post by mnjrutherford on Nov 28, 2010 13:27:41 GMT -5
So, the peanuts we are working on, are essentially "landrace". I have no idea what variety they are, but we've been selecting 2 years for pea size. As of this year we will be selecting for both the size of the pea and the number of peas per pod.
Right on or right off?
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Post by Alan on Nov 28, 2010 14:09:11 GMT -5
I certainly never meant to say no variables were selected for. Just the point that I always thought of breeding as breeding, and a landrace as a descriptive word for a type of a variety. A variety class. As opposed to a descriptive word for a type of breeding. I know how breeding is done, and how it was done in the past as well. Yes, but if your breeding goal involves creating a landrace then landrace breeding as a term makes sense. Jo, if you've mixed multiple varieties together and selected in a general direction that involves close to uniform maturity but alows for diverse phenotype, then yes. |
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Post by Joseph Lofthouse on Nov 28, 2010 14:31:14 GMT -5
Thats why I bred Astronomy Domine, so it would fall in the hands of guys like Joseph and Johno where it could evolve or be involved in the evolution of new, bio-regionally adapted, varieties, landraces, grexes. ext. This winter I sent significant quantities of Astronomy Domine sweet corn, Mendon Colorful Strain to a seed company in Europe, and to a farm co-op in Pakistan. Smaller quantities were distributed across the usa. I left the Astronomy Domine label on them so we'll see if it shows up in Europe or Asia. In a year or two when it's fully acclimatized, I intend to offer seed to my local garden seed sellers. |
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Post by honeydew on Nov 28, 2010 16:01:45 GMT -5
Okay thanks! That makes a lot more sense now....and opens up a whole new world. My idea of deliberate seed saving to this point included saving the purity of named varieties or improvement of said varieties.
So the same would go for other plants - say flowers?
Marie
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Post by littleminnie on Nov 28, 2010 17:46:55 GMT -5
From what did the term originate? asks the etymologist. I looked it up and it refers primarily to swine and then there is the pronounciation -I had no idea.  |
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Post by johno on Nov 28, 2010 18:07:48 GMT -5
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