Landrace versus grex

[terracotta]

Here is a breeding method for you to consider

With out-crossers I am growing an open pollinated crossing population with tremendous genetic diversity with F1 show up each year. In addition I can expect to be growing some percentage of F2, and F3 etc segregating crosses from previous seasons.

Then Divide the plants into about 4 seed groups based on their use/phenotype. In addition, it's very possible for varieties to switch between seed groups from year to year.

Is this the formula for making a landrace or a grex? Is something more needed for a landrace

[circumspice]

Truthfully, I don't know enough about the subject to cast a vote.

[terracotta]

thanks for letting me know I was trying to keep it impartial. here's some definitions to help

grex: A group name for all plants derived from crossing the same two or more parent species; the herd or hybrid swarm.
glossary.gardenweb.com/glossary/grex.html

landraces
1.Crop cultivars or animal breeds that evolved with, and has been genetically improved by, traditional agriculturalists, but has not been introduced in modern breeding practices.
glossary.gardenweb.com/glossary/grex.html
2. a variety grown in a region and that evolves somewhat "naturally" rather than through conscious, intensive selection. (seed savers exchange)
3. While landrace populations are variable,
diversity is far from random. They consist of mixture
of genotypes all of which are reasonably well adapted
to the region in which they evolved but which differ
in detail as to specific adaptations to particular conditions
within the environment. They differ in reaction
to diseases and pests, some lines being resistant or tolerant
to certain races of pathogens and some to other
races.

www.semencespaysannes.org/bdf/docs/landracereview-euphytica1998.pdf

[12540dumont]

Okay, I'm confused too.

That's okay, I've been that way since August.

Let's talk about squash for a minute. Say I have a field of 20 types of squash, "pepo's, moschatas, maximas, and a mixta if I can find one that tastes good". I have been growing and saving the seeds of all of these for 15 years.

Do I have a grex or a landrace? I started with a grex, but is it a landrace now? Does one evolve into the other? (I'll just say that those Pepos have been having random sex). I saw some pretty weird things come up in the chicken coop this year.

[terracotta]

Nov 30, 2012 14:38:45 GMT -5 12540dumont said:

Okay, I'm confused too.

That's okay, I've been that way since August.

Let's talk about squash for a minute. Say I have a field of 20 types of squash, "pepo's, moschatas, maximas, and a mixta if I can find one that tastes good". I have been growing and saving the seeds of all of these for 15 years.

Do I have a grex or a landrace? I started with a grex, but is it a landrace now? Does one evolve into the other? (I'll just say that those Pepos have been having random sex). I saw some pretty weird things come up in the chicken coop this year.

This is what I was trying to get at. When does someone have a landrace?
After a enviromental bottleneck such as this?

" Due to frost, the plot was harvested 88 days after sowing. Approximately 25% of the plants produced mature fruits and seeds. Many plants had not even set immature fruits in that time though they may have contributed some pollen."

garden.lofthouse.com/open-pollinated-butternut-moschata.phtml

[DarJones]

1 bottleneck a landrace does not make. I would say you need a period of years with a composite group of plants being affected by the same bottleneck repeatedly. This would result in a geoadapted landrace.

DarJones

[Joseph Lofthouse]

My Moschata squash growing season in 2010 was 88 days long. The 2012 frost free season was 84 days long... I don't know if I have the data recorded for 2009 and 2011, but it would be around 100 days or less, (notes not required for plant selection in my garden). The 2010 season, when I trialled so many new varieties sure thinned out the genepool, [around a 75% failure rate]. All of the 2012 moschatas were descendants of the 2010 population. I didn't actually measure it this year, but nearly every moschata in 2012 produced fruits and seeds. And so it goes year after year after year: my moschata landrace is drifting further and further away from the "mainstream" average moschata sold by The Company. I love seed swaps, but it gets increasingly difficult to find anything in any species that grows as well in my garden as my own seeds considering that my garden is non-average.

I sometimes wonder if every garden is non-average?

[bunkie]

Nov 29, 2012 21:53:07 GMT -5 @terracotta said:

Here is a breeding method for you to consider

With out-crossers I am growing an open pollinated crossing population with tremendous genetic diversity with F1 show up each year. In addition I can expect to be growing some percentage of F2, and F3 etc segregating crosses from previous seasons.

Then Divide the plants into about 4 seed groups based on their use/phenotype. In addition, it's very possible for varieties to switch between seed groups from year to year.

Is this the formula for making a landrace or a grex? Is something more needed for a landrace

i would consider it a grex. i think the thing missing to make it a landrace would be you picking for a new variety (out of your results) that is well productive in your area/zone. that's what i thought a landrace was more or less, creating/producing plant varieties that grow well in your own area.

[Joseph Lofthouse]

Historically, a grex has been defined as the offspring of an interspecific or intergeneric cross, and the back-crosses and hybrids of those crosses with each other and with the parent species. Historically, it would not be appropriate to describe as a grex: the cross between two cultivars of the same species.

But language evolves, and today, at least on this forum, and for followers of the work of Alan Kapuler, "grex" has come to mean the non-locally-adapted and/or not phenotypically stable offspring of a cross between cultivars of the same species. I think of my [landrace sweet corn X inbred sugary enhanced sweet corn] crosses as greges. Because while they are locally adapted and descended from a landrace, they are not harmonious enough in phenotype for me to call them a landrace. [The percentage of non se+ corn is still too high.]

[petitvilaincanard]

I like to use the term "population".It's neutral and generic.
For anything you can use "population" + description of genetic history of the population.No confusion possible.
You can invent a name for a population obtained by a certain method if it doesn't exist allready.
In your case you shouldn't call it landrace or grex because these terms apply to existing different situations.

[12540dumont]

One more question, do any of you find that starting with a landrace increases good results in your area? What about starting with a grex?

I know that I am blessed with normally good conditions and a long season. Most things will grow for me IF the seed is not too old and was mature when it was harvested. I have my failures, many times by not knowing what something looks like in the juvenile stage (zealous weeding, tsk tsk); planting in the wrong location - needed shade/sun/more heat; planting at the wrong time. In my climate, somethings that should be planted in June really need to be planted in May because after that it is just too hot.

Davida suffered some of this with beans that I have sent him. He should have planted earlier than what I recommended. Going forward, he will adjust my recommendations based on his experience with his own garden.

There are some things that just do not do well here. Edamame/soy beans. I cannot grow them for love nor money. They are a lost cause.

I have planted many of the grex's from AK and from LI and they have done well here. Landrace corn and beans from Native Seed Search have done very well on my farm, even though the conditions are substantially different. New Mexico is much more like Utah than California.

Joseph's Utah tomatoes were a stand out in my mater patch, but so was one of those from Tom Wagner in Oregon and one from Lieven in Belgium. Each of these outperformed ALL heirloom tomatoes, regardless of whether they were new to my farm, or replanted from my own seeds. Dar is sending me some of his heirloom seeds and I can't wait to trial his tomatoes. So, the location where the seeds came from appear not to be as important one would think, but all of these have come from the within a certain degree of latitude. Seeds from the Tarahumara are from a latitude much further south and have taken 2 years to really produce in my garden. I received few seeds the first year, and a bumper crop the next.

Questions, always more questions, always more to learn.

[castanea]

Oddly enough, Native Seed Search's Guarijio Red corn did extremely well for me this year. It was one of the most productive corns I have grown here.

[Joseph Lofthouse]

Dec 2, 2012 14:16:36 GMT -5 12540dumont said:

One more question, do any of you find that starting with a landrace increases good results in your area? What about starting with a grex?

I like starting with landraces or greges because it lets me screen more genomes with less effort.

If I start with named cultivars, then I have to acquire each cultivar, and plant each separately, and I have to grow enough of them that I have one to kill by my sloppy weeding, and one for bugs to kill, and one for the deer to step on, etc... And it gets pricey and labor intensive to grow-out so many named cultivars. For many out-crossing crops, I am going to end up chopping out most cultivars anyway before they set seed. My success rate varies by species. I have about a 95% success rate importing Swiss chard cultivars into my garden, but about a 95% failure rate with tomatoes, even when they are advertized as short-season. Failure rate on importing spinach, cantaloupe, and moschata cultivars is about 75%. The rate of success on pepos is about 50%, and it is 0% for arygrospermas.

But if I import a grex or a landrace, then I can plant one row of the new material, and select individuals from it that thrive in my fields. When I imported Alan's Tomato landrace into my garden, I discovered two useful plants, but the two rows I planted was equivalent to trialling dozens of cultivars, and the cost was for one packet of seeds.

Watermelon has been the most striking example of this: I have around a 99.9% failure rate when importing named cultivars of watermelons. Even when I imported Alan's watermelon Mass Cross, I had a 99.2% failure rate... But some local growers, and some Internet collaborators in cooler climates have been collaborating with me on developing watermelon for cooler short-season gardens. We took that 0.8% success and are building on it. When I import my collaborators proto-landraces, germination is still difficult, but nearly every plant that survives the early spring goes on to produce mature fruit.

[terracotta]

Dec 2, 2012 11:43:00 GMT -5 petitvilaincanard said:

I like to use the term "population".It's neutral and generic.
For anything you can use "population" + description of genetic history of the population.No confusion possible.
You can invent a name for a population obtained by a certain method if it doesn't exist allready.
In your case you shouldn't call it landrace or grex because these terms apply to existing different situations.

like adaptivar? it's on his website.

[petitvilaincanard]

Dec 2, 2012 21:03:18 GMT -5 @terracotta said:

Dec 2, 2012 11:43:00 GMT -5 petitvilaincanard said:

I like to use the term "population".It's neutral and generic.
For anything you can use "population" + description of genetic history of the population.No confusion possible.
You can invent a name for a population obtained by a certain method if it doesn't exist allready.
In your case you shouldn't call it landrace or grex because these terms apply to existing different situations.

like adaptivar? it's on his website.

You got me