Author Topic: Clever tricks for dealing with low populations of corn ?  (Read 2072 times)

spacecase0

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #15 on: 2020-07-14, 10:47:57 PM »
I dont understand how this works, can you explain please.
so what I said in reply #6 of this thread was not clear enough...

let me try to do better
silks from the lower part of the cob show up before the ones from the upper part of the cob,
so, you are selecting for sooner or later if you save the seeds from the ends of the cobs

Joseph Lofthouse

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #16 on: 2020-07-20, 10:16:02 AM »
silks from the lower part of the cob show up before the ones from the upper part of the cob, so, you are selecting for sooner or later if you save the seeds from the ends of the cobs

The other half of the equation would be that, presumably, some of the later appearing silks might be pollinated by other plants that tasseled later, and thus lengthening the days to maturity.

But it wouldn't matter for those seeds which are selfed, because they have the same mother and father. And it wouldn't matter for highly uniform varieties where the whole population tassels at the same time.

Yaz

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #17 on: 2020-08-05, 08:05:37 PM »
My fussing aside, looks like I got corn cobs after all.
Interestingly, a lot of the first to tassle plants were last to silk, and a couple silked before tassling. Combined with some other weirdness in morphology, I can confidently say that the Painted Mountain corn plants dont read internet articles on the stages of corn formation :) I am shocked by how tall it got, the tallest is maybe 7-8 ft, way taller than the local commercial corn.

I counted 62 cobs today, not counting the couple of stalks that have fallen over. Most have 2 cobs/stalk, or none. Several ears have overshot the husks. 

I really need to have a bigger population size to work with. I would like to cull probably 30% if possible. Instead, I detassled 3 or 4. Surviving/producing/not falling over is the only other selection I have done.  I do have beans climbing some of them, and doing well and holding things up.

Plan for next year is definitely to increase the size of the corn patch assuming I use the flour,  I am enjoying growing them. Maybe also use the smaller spacing of the two I trialed, I am not yet seeing any difference in productivity between the two spacings. 

S.Simonsen

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #18 on: 2020-08-06, 01:10:03 AM »
One way to avoid inbreeding depression in small population sizes would be to form a small group of growers that regularly exchange seed. That keeps the effective population size larger (and also provides some insurance against one person losing the strain).

Yaz

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #19 on: 2020-09-01, 11:41:28 AM »
Well... all my flour corn is harvested now. Not sure if I would call it a success.

 I got maybe 25 cobs off the patch, the local wildlife probably got a similar number. I have saved seeds into 4 seperate identical jars/copies, using the criteria of saving one seed to each batch for every cob, and 2 seeds if it was a particularly impressive cob. I chose to save seeds from the bottoms of the cobs in an atempt to encourage earlier maturity, it would ideally be nice two beable to grow 2 varieities  (flour corn and a popcorn) seperated by time, and this variety started drying down almost 2 months before first frost date, 

Notes/lessons learned
-  I think I need to move towards a uniform harvesting/ripening date. As is, it took a month with a few cobs drying down while others were still silking, which was plenty of time for the local wildlife to find out and invite their friends to the feast. Later maturing cobs had far more predation. Later cobs also had disappointing pollination. Don't regret overseeing a second batch, but will over plant in the future to avoid it.
- Beans climbing the corn was disappointing. By the time the beans have begun to mature, the corn stalks are almost dead, so the beans are pulling them down, might work for a longer seasoned variety. No difference earlier in lodging between my rows with beans and rows without. Got far better production in the shaded corn of beans than in my normal bean area.
- i tried a few different spacings/plantings. Larger spacing didn't seem to make much of a difference, except that those in grew in clumps were not as successful as those grown in rows.
- many overshot corn husks, but I think those were somewhat selected against as those were the birds favourites

I am hoping to try a bigger patch next year with a mix of saved and purchased seed, and see if my saved seed does better than the purchased, which would be encouraging, I would also consider bringing in another variety or at least another seed source into the mix.

Plantman

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #20 on: 2021-02-13, 05:16:19 AM »
Documenting here, as I tend to lose garden journals.

Currently have aproximately 64 corn plants growing, mostly short/small - hard to tell in some cases if things are a tiller or another corn plant since I planted in clumps. It's been a drought here (more than a month since last rain) and unseasonably hot since I planted, and I've not watered enough, probably. Every time I water, the corn seems to jump 6" overnight. Tallest corn is now chin height (on my 5'4 self), most (likely the second batch) is probably waist height or shorter. The biggest corn has been tasselling for a few weeks now, but I see no signs of silks forming, but the beginnings of cobs on some of the largest plants. Oh, and there are definitely bugs crawling in the smaller corn cobs.

My corn does look nicer than the commerical corn I see while driving - farmers don't typically irrigate here, so the corn is less than waist high (maybe knee high), and I suspect from the close spacing most is grown for silage.

I am considering if I should introduce another/different flour corn into the mix next year for diversity (Cherokee White?), possibly one developed for the hot/humid climate of the east, rather than the cooler/drier climate of Montana. It gets tricky, as the growing season here is still short. I'd prefer not to "lose" this year of corn selection for my climate, but also don't want to kill it with inbreeding. Or perhaps just presoak the seeds, and start it earlier when there is (usually) more water/cooler temps.

Yaz, do you honestly believe that you will inbreed your corn to the point you will kill it?

If you are only breeding one strain, then of course you are going to suffer some inbreeding depression.
The corn you have chosen was created by a very talented breeder from something like 60 varieties.
There is a lot of genetic wealth in your seed.

Here is a strategy you may wish to follow.
Grow your corn.
As much as yoir space and efforts will allow
If you notice some inbreeding depression, then introduce a new batch of the same corn.
If yours is truly inbred to the point of lower vigour, it would give you hybrid vigour with the new corn, but maintain the same general genotype

If you do want to add a completely new line to your patch, Puruvian morado will enjoy a cooler climate, or even Montana lavender clay that is also bred by the same guy as your painted mountain.
Both have a good amount of anthocyanin, so will be nutritious as well as attractive.

Combining different generations of your same seed is a sound technique, but I don't understand why the 200 plant minimum.
The Feroes island horse breed was repoulated from only 5 inbred individuals.
« Last Edit: 2021-02-13, 05:51:27 AM by Plantman »

reed

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #21 on: 2021-02-13, 06:30:27 AM »
I believe the 200 plant minimum comes from the book "Seed to Seed" by Suzanne Ashworth. I also believe it mostly pertains to grossly inbred varieties. Painted Mountain was bred from many lines but I wonder if the 200 rule might still apply. I wonder that because the very specific mountain environment where it was bred might have quite rapidly reduced it to some very specific traits. It does not do well at all here in Indiana, nearly all ears overshoot the husks badly. Carol Deppe's manna series is selected from PM and also has that problem but not quite as bad.

I've heard it said that as long as the original patents represented a wide enough cross, that is different in many ways, that a single ear or even a single kernel could give rise to a new variety. I haven't been quite that limited, but that's the path I've taken and seems to be working very well, even in small populations.
« Last Edit: 2021-02-13, 06:32:43 AM by reed »

Andrew Barney

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #22 on: 2021-02-13, 07:37:08 AM »
That isn't a bad idea anyway if you are looking for genetic diversity.  Ordering from multiple seed sellers may offer a different genetic mix.

This. I always do this for new corn seed. I also like to at least double up the seed order from each company if possible as well. A tiny little seed packet wont necessarily have much genetic diversity from the population and some seed companies may have started with only a packet of seed to grow themselves. I also like to bet against shady seed sellers in case they are lying about the seed they sold me. Buying the same variety from multiple sellers gives me peace of mind.

For my purple foliage corn population i like to periodically add in new seed from new varieties into the mix.

An example is i want to someday grow glass gem corn and add it to my population. But i also want as much genetic diversity within glass gem as possible. Does anyone know which seed company first introduced glass gem? They probably have the most diversity of that variety i would expect, so i should probably order from them.

Plantman

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #23 on: 2021-02-13, 08:09:19 AM »
This. I always do this for new corn seed. I also like to at least double up the seed order from each company if possible as well. A tiny little seed packet wont necessarily have much genetic diversity from the population and some seed companies may have started with only a packet of seed to grow themselves. I also like to bet against shady seed sellers in case they are lying about the seed they sold me. Buying the same variety from multiple sellers gives me peace of mind.

For my purple foliage corn population i like to periodically add in new seed from new varieties into the mix.

An example is i want to someday grow glass gem corn and add it to my population. But i also want as much genetic diversity within glass gem as possible. Does anyone know which seed company first introduced glass gem? They probably have the most diversity of that variety i would expect, so i should probably order from them.

It's a good idea to buy from multiple supliers. If thet have held their stock for more than a couple years you should get some degree of heterosis from the *outcross* to a population of the same line.

Breeding your purple corn as a type, rather than a variety is something more people should consider.
A seed permaculture centre (drylands.org.au) near to me only sells blends of peas, so first year saving is an F1.

From what I see from the glass corn a few ppl are breeding their own types, so you should be able to find good quality inbred populations to play with.
If it wasn't a popcorn I'd jump in.  It's so pretty.

« Last Edit: 2021-02-13, 09:32:20 AM by Plantman »

Plantman

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #24 on: 2021-02-13, 08:27:49 AM »
I believe the 200 plant minimum comes from the book "Seed to Seed" by Suzanne Ashworth. I also believe it mostly pertains to grossly inbred varieties. Painted Mountain was bred from many lines but I wonder if the 200 rule might still apply. I wonder that because the very specific mountain environment where it was bred might have quite rapidly reduced it to some very specific traits. It does not do well at all here in Indiana, nearly all ears overshoot the husks badly. Carol Deppe's manna series is selected from PM and also has that problem but not quite as bad.

I've heard it said that as long as the original patents represented a wide enough cross, that is different in many ways, that a single ear or even a single kernel could give rise to a new variety. I haven't been quite that limited, but that's the path I've taken and seems to be working very well, even in small populations.

Thank you.
So someone says something like, with an inbred population it would be good to have at least 200 individuals to maintain diversity, and a little down the track people start thinking they can't breed with less than 200.
Bit further down the track people start believing that anything less than 200 and the population will collapse.

I appreciate how you are using smaller batches. It allows closer observation, better care.

I only bought 100  Hopi pink and 100 Hopi turquoise to go with 100 Hopi blue to start some flour corn up.
They won't all germinate and I will cull plants before they throw pollen.

I wonder if you had a really small amount of corn, it would be worth neutering half the plants.
If you only repopulated a depressed population with the seed from the neutered corn there would be no self pollinated seed planted, at least
You could introduce the other half of the seed crop in later season.
« Last Edit: 2021-02-14, 01:53:03 AM by Plantman »

Jeremy Weiss

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #25 on: 2021-02-13, 09:10:20 AM »
I find this all very useful since I am ALWAYS dealing with less than 200 plants (I only have room for 100, max, and have less than that of most seed lines).

I suppose it also depends on what one is trying to do with the corn.  For a lot of my stuff, a fair amount of inbreeding is desirable, since I am trying to "clean up" random corn selected by appearance in order to make a line that has that appearance consistently (for example, getting the floury kernels of a flour/flint with mostly flint corn to get to a point where it is mostly to ideally ALL floury.)

MOST of my corn lines are, or start single ear or two  since that is what I find. I get the idea of landraces and grexes but these seem to be for when you are trying to get yield for a region, not for any given appearance. If I tried to do a landrace with my stuff, I'd probably get junk of no use for any further breeding.

Andrew Barney

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #26 on: 2021-02-13, 09:46:05 AM »
My purple corn population has traditionally been planted in a roughly 10ft x 10ft square,  so 100 plants each season and I think it is doing okay.

I think the key is that you do what works for you. I think landrace or grex could still work for you,  but it would be with only the traits you want. You could only plant flour types for example or only those with some other trait. You could still potentially be mixing lots of varieties, but they would be carefully chosen parent varieties.

You could try the detasseling idea. I like it. It also could help if you detasseled all the flints and that way they would back cross to the flour types quicker.

Jeremy Weiss

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Re: Clever tricks for dealing with low populations of corn ?
« Reply #27 on: 2021-02-13, 12:22:20 PM »
Technically, the flour corn is ALREADY a grex, as the kernels (unlike most of my corns) came from many many cobs. I just selected and kept those kernels that met my requirements and discarded the others, which has resulted in a seed sample that LOOKS like it all came from one solid white ear (all of the ears were multicolored to start with, but for reasons I don't quite understand there were few that showed full soft starch AND color of either aleurone or pericarp, So the sample looks all white, with the odd pale yellow kernel). That and being miniature corn is all they have in common.  The stuff is actually probably heterogeneous for pretty much everything else including such fundamental things as ear shape (some are probably normal "carrot" shape some are likely the stubbier shape a lot of the early accessions were.  I'm just hoping that with a few generations of pollinating each other, the number of floury kernels (which probably wasn't above twenty per ear on any) goes up (if the colors come back that will be kept as well, since I can't see any use for this or most of my corns except ornamental purposes.) I actually still have three colored ones that passed (two red one speckled) that I will add in once the flour is better esablished.

Besides this I also have

Accession 2: miniature dent, 24 rows, gourdseed kernels stubby cob, white yellow and pink remnants of one ear (about half or 200 or so kernels)

Accession 3: miniature dent  16 rows, possibly gourdseed shape (it's sometimes hard to tell with miniature corns, whose kernels are often longer and thinner than full size anyway) normal cob, white yellow pink magenta and purple  probably about 200 again.

Accession 4: miniature red dent  rice type kernels stubby cob. Almost certainly the result of a strawberry/field corn cross. two ears worth (maybe 300 kernels)

Accession 5-6 miniature sweet corn, small (maybe 20-30 kernels) from two ears (one with wide loaf shaped kernels and stubby cob, one with narrow ones and long cob)

Full sized dent corn with strong stippling 2 ears 100 or so kernels total  (one ear is a little wider kernelled than the other) white yellow and purple

Full sized stippled flint corn wider color mix than above so being added for improved color (has blue and pink and the yellow back red brown and black)

And then of corse there is the bottle where I toss any sweet kernels I find in ears of Ornamental corn and a little named stuff (like some Volta White)