Saving seeds from X number of plants

jmsieglaff · February 27, 2015

In a recent thread I saw this link posted (http://www.savingourseeds.org/publications.html) and was reading about saving tomato seeds (a good read BTW). Anyway, it reminded me about reading in various books and in within threads here about the proper way to save tomato seeds--specifically about saving seeds from a fairly large number of plants to maintain genetic diversity.

So my question is how many people when they save seeds are saving them from a large number of plants or at least the 'minimum' number of plants? The diversity of tomato growers here is large, from backyard gardeners to backyard breeders, to market growers, to full scale commercial breeders, so the answers will vary substantially I believe.

I am a backyard gardener who has started saving seeds. I enjoy trying new varieties and don't have space to grow multiple plants of each variety, I'd rather grow one plant of 8 or 10 varieties than 4 or 5 plants of 2 varieties. Am I doing a disservice to the tomato world by saving tomato seeds from one plant? Obviously when breeding a tomato you need to save seeds from single plants based on the traits you are looking for, but that's not what I'm talking about here. I'm talking about saving seeds of stable OP varieties.

I've done a lot of reading about tomatoes, but one thing I do not quite understand fully is the concept of maintaining genetic diversity for inbreeding plants like tomatoes. If an heirloom has been grown for decades or even 100 years and over that time nearly all loci have become homozygous, where is this genetic diversity? Or is the genetic diversity related to so many (thousands of loci??) that there are still a few heterozygous loci and some segregation going on an this somehow results in vigor/production (lack of inbreeding depression)?

Maybe I've opened a can of worms, but I want to understand the concept fully. I have found saving seeds enjoyable and wonder if my growing setup (one plant of most varieties) is an issue with saving seeds.

KarenO · February 28, 2015

I save my seed from the best, healthiest most productive plant. I never save seed from weak or diseased plants.
Survival of the fittest and genes from the best plant to pass down. My seeds are for my own use or for trading. I do not sell seed.
KarenO

Darren Abbey · February 28, 2015

It really depends on the type of plant. Some plants show significant inbreeding depression if you don't have a diverse enough population. Tomatoes and squash generally don't show this problem, while corn definitely does.

drew51 · February 28, 2015

You are assuming too much. Crosses happen and may not show much change, but over time do. Also all genes are not homozygous, just look at Brandywine and all the strains or sub-strains. The hard thing to do is keep a heirloom from changing.
I myself don't care if some of mine cross either. I don't isolate blossoms and bees visit mine all the time. Inbreeding is not really a good term, it has more social meaning than anything. Some organisms produce asexually, so talk about inbreeding!
I was interested in growing Indian Stripe, it originated from Cherokee Purple. Seemed to grow better, I now have Indian Stripe potato leaf, and Indian Stripe heart, all variations within the same heirloom, no genes are not that stable, everything is a hybrid.

**carolyn137** · February 28, 2015

The orignal suggestion from years ago when I first started saving seed was to plant out no less than 4 plants of a single variety in a row and save seeds from only the middle ones.

Of course that didn't take into consideration what might be planted in the rows on either side which could often be a source of cross pollination.

For many years I was growing many hundreds of plants and varieties in a single season, mostly for my SSE listings and seed offers which I started doing back in about 1990.

To help preserve genetic diversity within a variety, and it does exist, I never saved seeds from a single plant if I could help it. Saving seeds from two plants is much better, etc.

Of course all of this is also related to when you save seeds as to the frequency of pollinators in your own area. For me they were most active early in the season so I saved seeds from fruits that developed later in the season.

The Brandywine situation is not one of instability at all. Which brings up the issue of what a strain is and there are two ways of looking at it. Many of the Brandywines were first SSE listed by the name of the person who last grew it and listed it, so we have the Sudduth/Quisenberry one, Glicks, and many more like that with a personal name attached and those who have grown out many of such strains find little difference between them.

The other kind of strain is when there's an actual difference from the original yet the strain can still be IDed as being from the original, and an example of that is Brandywine Yellow, Platfoot strain.

The same situation also exists with most of the mortgage Lifter versions, most were listed with the name of the person who last grew it and SSE listed it, but one, for instance, the Mortgage Lifter, Estler, is, in the opion of many, including me, far better as to yield, taste, etc, than other Mortgage Lifters.

Hope that helps,

Carolyn, who almost forgot to mention that tomatoes are not inbreeders so do not show inbreeding depression as do corn, etc.

jmsieglaff · February 28, 2015

Thanks for the comments thus far. A few specific comments/questions remain.

Quote:

Originally Posted by KarenO

I save my seed from the best, healthiest most productive plant. I never save seed from weak or diseased plants.
Survival of the fittest and genes from the best plant to pass down. My seeds are for my own use or for trading. I do not sell seed.
KarenO

I'm with you on those accounts Karen! I more ask the question for the sake of knowledge. I enjoy saving seeds and trading with others, so I will continue to do that.

Quote:

Originally Posted by carolyn137

To help preserve genetic diversity within a variety, and it does exist, I never saved seeds from a single plant if I could help it. Saving seeds from two plants is much better, etc.

I guess there is something related to genetics that I do not understand yet. If a variety has been successfully saved without crossing for decades, most (hard to definitively say all) loci have become homozygous. So where does the genetic diversity come from?

Quote:

Originally Posted by carolyn137

Of course all of this is also related to when you save seeds as to the frequency of pollinators in your own area. For me they were most active early in the season so I saved seeds from fruits that developed later in the season.

So is the idea of saving seed from multiple fruits from multiple plants to reduce the possibility one could unknowingly maintain an OP variety with a cross that in the outward appearance was too subtle to notice? A specific example of what I'm getting at is say I grow 1 plant of variety X in year 1 and save seed from a couple fruits. Say a few of those seeds within those fruits were cross pollinated while most were self pollinated. In year 2 if I grow 1 plant from the saved seed lot and I happen to grow a plant from a crossed seed two things could happen. 1) I can tell it is a cross, identify it as such and do not save fruit from that plant as the OP variety or 2) The outward appearance of the tomato isn't really different enough to suggest a cross pollination and I save seed from that plant as the OP line and I have now have saved seed of Tomato X but it really isn't. I suppose in this example growing more than 1 plant of from a saved batch of seeds could allow me to see differences between a crossed seed (that only very subtly appears different) and non-crossed seeds that I wouldn't have noticed otherwise.

**carolyn137** · February 28, 2015

[QUOTE=jmsieglaff;453852]Thanks for the comments thus far. A few specific comments/questions remain.

I'm with you on those accounts Karen! I more ask the question for the sake of knowledge. I enjoy saving seeds and trading with others, so I will continue to do that.

I guess there is something related to genetics that I do not understand yet. If a variety has been successfully saved without crossing for decades, most (hard to definitively say all) loci have become homozygous. So where does the genetic diversity come from?

So is the idea of saving seed from multiple fruits from multiple plants to reduce the possibility one could unknowingly maintain an OP variety with a cross that in the outward appearance was too subtle to notice? A specific example of what I'm getting at is say I grow 1 plant of variety X in year 1 and save seed from a couple fruits. Say a few of those seeds within those fruits were cross pollinated while most were self pollinated. In year 2 if I grow 1 plant from the saved seed lot and I happen to grow a plant from a crossed seed two things could happen. 1) I can tell it is a cross, identify it as such and do not save fruit from that plant as the OP variety or 2) The outward appearance of the tomato isn't really different enough to suggest a cross pollination and I save seed from that plant as the OP line and I have now have saved seed of Tomato X but it really isn't. C

&&&&&&&&&&

The main reason for saving seeds from several plants is to lessen the probability that an off type will appear. I've saved a couple of thousand seeds of a variety and distributed up to a thousand of them for SSE listings and seed offers before even ONE offtype would appear, and you'd know it was an offtype since it would bear no resemblance at all to the original.

All it takes is ONE blossom that has been X pollinated to introduce contaminated seeds to the batch.

Home gardeners saving much less seeds than I did, may or may not see an off type depending on all the variables I mentioned above.

(The outward appearance of the tomato isn't really different enough to suggest a cross pollination and I save seed from that plant as the OP line and I have now have saved seed of Tomato X but it really isn't. C)

Yes, as I said above the off type would not resemble the original in any way.

(I guess there is something related to genetics that I do not understand yet. If a variety has been successfully saved without crossing for decades, most (hard to definitively say all) loci have become homozygous. So where does the genetic diversity come from?)

I never undderstood this myself until Keith Mueller pointed out to me that within each variety there are subtle differences that do show up for those who have eyes to see. And I put out many plants of a variety and yes, I did see, issues such has subtle differences in leaf form, internode distances, time to first fruits, etc. Whether this is due to subtle mutations, I think so myself and whether all stable varieties are completley homozygous, I doubt it.

I have grown many varieties that have maintained the original descriptions going back to the mid 1800's such as Trophy, Livingston varieties and many more. So perhaps some varieties are more susceptible to those subtle mutations.

Hope that helps, and if I haven't addressed some of your questions clearly, where there are answers, please ask again.

Carolyn

frdlturner · February 28, 2015

So what if I was to plant 4 plants in a square and plant a fifth one in the middle of the 4 would the fifth have a better chance of not crossing since it is in the middle.

jmsieglaff · February 28, 2015

Thanks Carolyn I think that answers things in my mind. The concept of all loci becoming homozygous is likely oversimplifying nature especially when mutations are considered.

Your point about subtle differences, how ever they appear, are things that one probably only notices when plants are side by side and not from memory from year to year.

Now spring needs to come!

Justin

drew51 · February 28, 2015

I grow mostly paste tomatoes and sauce tomatoes, I'm not that concerned about crosses. Some look alike, so i doubt I could tell with some pastes. I will trade seed, but let person know always a chance of a cross. I'm doing some isolating of other flowers so i might try bagging some of the tomato flowers this year for fun and non-profit.

joseph · February 28, 2015

I think that it is better to save seeds than to not save seeds.

I think that many people get so fearful about saving seeds wrong that they let the fear inhibit them from saving seeds. As far as I am concerned, the important thing is to be saving seeds, not to be worrying about isolation, or pollination, or diversity, or names, or history, or purity, or stability. Seed saving is magical. It is revolutionary. It is spiritual. It is built into our DNA. Sure, seed saving has had a rational/scientific overlay imposed on it. But fundamentally, seed saving is a visceral activity that has been practiced by animals since before the origins of our species. Seed saving is built into the core of our beings. I think that it doesn't matter what techniques we use -- if we are saving seeds we will be more connected to ourselves and to the world around us.

If we are worried about maintaining genetic diversity, then we can maintain more genetic diversity by saving seeds from one plant of 6 different varieties than we would get from saving seeds from 1000 plants of a stabilized (near clonal) variety.

To me, saving seeds is magical... It connects me with the world around me. The seeds become part of my family as I steward them year after year, and they get more and more attuned to my taste preferences and ways of doing things.

**carolyn137** · February 28, 2015

Quote:

Originally Posted by frdlturner

So what if I was to plant 4 plants in a square and plant a fifth one in the middle of the 4 would the fifth have a better chance of not crossing since it is in the middle.

What you are talking about is basically a Japanese ring structure type of growth;

https://www.google.com/?gws_rd=ssl#q...o+ring+growing

And I doubt that your center one would be protected from X pollination by those around it.

Look at it this way. If the pollinator version of the FAA resticted those insects to flying only at a certain altitude and in a straight line so they would first make contact with the outer ones one, that might help, but that's not the way things work.

The pollinators can go anywhere they want to whenever they want to and do so.

And pollinators are also known to be able to fly more than a mile in pursuit of pollen, so there's that as well.

Carolyn

JamesL · February 28, 2015

Quote:

Originally Posted by joseph

I think that it is better to save seeds than to not save seeds.

Seed saving is magical. It is revolutionary. It is spiritual. It is built into our DNA.

"Like button" to this Joseph!
I would agree with many of the other comments, but this strikes a particular chord with me.

**carolyn137** · February 28, 2015

Quote:

Originally Posted by joseph

I think that it is better to save seeds than to not save seeds.

I think that many people get so fearful about saving seeds wrong that they let the fear inhibit them from saving seeds. As far as I am concerned, the important thing is to be saving seeds, not to be worrying about isolation, or pollination, or diversity, or names, or history, or purity, or stability. Seed saving is magical. It is revolutionary. It is spiritual. It is built into our DNA. Sure, seed saving has had a rational/scientific overlay imposed on it. But fundamentally, seed saving is a visceral activity that has been practiced by animals since before the origins of our species. Seed saving is built into the core of our beings. I think that it doesn't matter what techniques we use -- if we are saving seeds we will be more connected to ourselves and to the world around us.

If we are worried about maintaining genetic diversity, then we can maintain more genetic diversity by saving seeds from one plant of 6 different varieties than we would get from saving seeds from 1000 plants of a near clonal variety.

To me, saving seeds is magical... It connects me with the world around me. The seeds become part of my family as I steward them year after year, and they get more and more attuned to my taste preferences and ways of doing things.

Joseph, what you do works for you since you don't sell seeds or make large seed offers, or list seeds in for instance the SSE yearbooks, but for many of us it doesn't work.

And I will gently disagree with with what you said above that I bolded. That is, that saving seeds from one plant of 6 different varieties preserves genetic diversity better than saving seeds from a clonal variety. And I know it's clonal varieties you prefer to work with, you've made that very clear, but I have a hard problem seeing how your clonal ones are doing a better job of it.

Granted they might, but not known for sure as I see it.

Carolyn

joseph · February 28, 2015

Carolyn: I belong to a tribe. Within my tribe we share seeds widely, both commercially, and by ad-hoc methods. We are perfectly content that the seeds don't have names or pedigrees. Our seeds have phenotypes: Cherry tomatoes, cold tolerant tomatoes, Red Slicing Tomatoes. It works for my tribe. It may not work for other peoples.

My apologies for confusing you... When I write about a "near clonal variety" of tomato, I am referring to stabilized varieties. Those would be a typical heirloom tomato variety, or a typical commercially available F1 hybrid. Sure, they have a teeny-tiny amount of genetic diversity within them, but even if we grow out a field with 1000 plants of a single variety, there is very little genetic diversity within that field... I'm pretty sure that if a person grew 6 different (stabilized or hybrid) varieties of tomatoes and ran DNA analysis, that the combined DNA would contain much more genetic diversity than a whole field of a single stabilized (or as I call them near-clonal) variety.

I do not grow stabilized varieties of tomatoes. There is nothing near-clonal about what I grow. I grow mongrels, creoles, etc... I'd take my previous statement one step further, and speculate that there may be more genetic diversity within the offspring of any single plant from my promiscuously pollinating tomato project than there is within a field containing 1000 plants of a single stabilized variety.

As far as I can tell, we preserve more genetic diversity by saving seeds from (even a single fruit of) several different varieties than we do by saving seeds from more plants of a single stabilized or hybrid variety.

February 27, 2015	#1
jmsieglaff Tomatovillian™ Join Date: Jan 2014 Location: Southern WI Posts: 2,742	Saving seeds from X number of plants In a recent thread I saw this link posted (http://www.savingourseeds.org/publications.html) and was reading about saving tomato seeds (a good read BTW). Anyway, it reminded me about reading in various books and in within threads here about the proper way to save tomato seeds--specifically about saving seeds from a fairly large number of plants to maintain genetic diversity. So my question is how many people when they save seeds are saving them from a large number of plants or at least the 'minimum' number of plants? The diversity of tomato growers here is large, from backyard gardeners to backyard breeders, to market growers, to full scale commercial breeders, so the answers will vary substantially I believe. I am a backyard gardener who has started saving seeds. I enjoy trying new varieties and don't have space to grow multiple plants of each variety, I'd rather grow one plant of 8 or 10 varieties than 4 or 5 plants of 2 varieties. Am I doing a disservice to the tomato world by saving tomato seeds from one plant? Obviously when breeding a tomato you need to save seeds from single plants based on the traits you are looking for, but that's not what I'm talking about here. I'm talking about saving seeds of stable OP varieties. I've done a lot of reading about tomatoes, but one thing I do not quite understand fully is the concept of maintaining genetic diversity for inbreeding plants like tomatoes. If an heirloom has been grown for decades or even 100 years and over that time nearly all loci have become homozygous, where is this genetic diversity? Or is the genetic diversity related to so many (thousands of loci??) that there are still a few heterozygous loci and some segregation going on an this somehow results in vigor/production (lack of inbreeding depression)? Maybe I've opened a can of worms, but I want to understand the concept fully. I have found saving seeds enjoyable and wonder if my growing setup (one plant of most varieties) is an issue with saving seeds.

February 28, 2015	#3
Darren Abbey Tomatovillian™ Join Date: Jun 2012 Location: Minnesota Posts: 586	It really depends on the type of plant. Some plants show significant inbreeding depression if you don't have a diverse enough population. Tomatoes and squash generally don't show this problem, while corn definitely does. __________________ http://the-biologist-is-in.blogspot.com

February 28, 2015	#5
carolyn137 Moderator Emeritus Join Date: Jan 2006 Location: Upstate NY, zone 4b/5a Posts: 21,169	The orignal suggestion from years ago when I first started saving seed was to plant out no less than 4 plants of a single variety in a row and save seeds from only the middle ones. Of course that didn't take into consideration what might be planted in the rows on either side which could often be a source of cross pollination. For many years I was growing many hundreds of plants and varieties in a single season, mostly for my SSE listings and seed offers which I started doing back in about 1990. To help preserve genetic diversity within a variety, and it does exist, I never saved seeds from a single plant if I could help it. Saving seeds from two plants is much better, etc. Of course all of this is also related to when you save seeds as to the frequency of pollinators in your own area. For me they were most active early in the season so I saved seeds from fruits that developed later in the season. The Brandywine situation is not one of instability at all. Which brings up the issue of what a strain is and there are two ways of looking at it. Many of the Brandywines were first SSE listed by the name of the person who last grew it and listed it, so we have the Sudduth/Quisenberry one, Glicks, and many more like that with a personal name attached and those who have grown out many of such strains find little difference between them. The other kind of strain is when there's an actual difference from the original yet the strain can still be IDed as being from the original, and an example of that is Brandywine Yellow, Platfoot strain. The same situation also exists with most of the mortgage Lifter versions, most were listed with the name of the person who last grew it and SSE listed it, but one, for instance, the Mortgage Lifter, Estler, is, in the opion of many, including me, far better as to yield, taste, etc, than other Mortgage Lifters. Hope that helps, Carolyn, who almost forgot to mention that tomatoes are not inbreeders so do not show inbreeding depression as do corn, etc. __________________ Carolyn

February 28, 2015	#7
carolyn137 Moderator Emeritus Join Date: Jan 2006 Location: Upstate NY, zone 4b/5a Posts: 21,169	[QUOTE=jmsieglaff;453852]Thanks for the comments thus far. A few specific comments/questions remain. I'm with you on those accounts Karen! I more ask the question for the sake of knowledge. I enjoy saving seeds and trading with others, so I will continue to do that. I guess there is something related to genetics that I do not understand yet. If a variety has been successfully saved without crossing for decades, most (hard to definitively say all) loci have become homozygous. So where does the genetic diversity come from? So is the idea of saving seed from multiple fruits from multiple plants to reduce the possibility one could unknowingly maintain an OP variety with a cross that in the outward appearance was too subtle to notice? A specific example of what I'm getting at is say I grow 1 plant of variety X in year 1 and save seed from a couple fruits. Say a few of those seeds within those fruits were cross pollinated while most were self pollinated. In year 2 if I grow 1 plant from the saved seed lot and I happen to grow a plant from a crossed seed two things could happen. 1) I can tell it is a cross, identify it as such and do not save fruit from that plant as the OP variety or 2) The outward appearance of the tomato isn't really different enough to suggest a cross pollination and I save seed from that plant as the OP line and I have now have saved seed of Tomato X but it really isn't. C &&&&&&&&&& The main reason for saving seeds from several plants is to lessen the probability that an off type will appear. I've saved a couple of thousand seeds of a variety and distributed up to a thousand of them for SSE listings and seed offers before even ONE offtype would appear, and you'd know it was an offtype since it would bear no resemblance at all to the original. All it takes is ONE blossom that has been X pollinated to introduce contaminated seeds to the batch. Home gardeners saving much less seeds than I did, may or may not see an off type depending on all the variables I mentioned above. (The outward appearance of the tomato isn't really different enough to suggest a cross pollination and I save seed from that plant as the OP line and I have now have saved seed of Tomato X but it really isn't. C) Yes, as I said above the off type would not resemble the original in any way. (I guess there is something related to genetics that I do not understand yet. If a variety has been successfully saved without crossing for decades, most (hard to definitively say all) loci have become homozygous. So where does the genetic diversity come from?) I never undderstood this myself until Keith Mueller pointed out to me that within each variety there are subtle differences that do show up for those who have eyes to see. And I put out many plants of a variety and yes, I did see, issues such has subtle differences in leaf form, internode distances, time to first fruits, etc. Whether this is due to subtle mutations, I think so myself and whether all stable varieties are completley homozygous, I doubt it. I have grown many varieties that have maintained the original descriptions going back to the mid 1800's such as Trophy, Livingston varieties and many more. So perhaps some varieties are more susceptible to those subtle mutations. Hope that helps, and if I haven't addressed some of your questions clearly, where there are answers, please ask again. Carolyn __________________ Carolyn

February 28, 2015	#11
joseph Tomatovillian™ Join Date: May 2013 Location: Cache Valley, N/E of The Great Salt Lake Posts: 1,244	I think that it is better to save seeds than to not save seeds. I think that many people get so fearful about saving seeds wrong that they let the fear inhibit them from saving seeds. As far as I am concerned, the important thing is to be saving seeds, not to be worrying about isolation, or pollination, or diversity, or names, or history, or purity, or stability. Seed saving is magical. It is revolutionary. It is spiritual. It is built into our DNA. Sure, seed saving has had a rational/scientific overlay imposed on it. But fundamentally, seed saving is a visceral activity that has been practiced by animals since before the origins of our species. Seed saving is built into the core of our beings. I think that it doesn't matter what techniques we use -- if we are saving seeds we will be more connected to ourselves and to the world around us. If we are worried about maintaining genetic diversity, then we can maintain more genetic diversity by saving seeds from one plant of 6 different varieties than we would get from saving seeds from 1000 plants of a stabilized (near clonal) variety. To me, saving seeds is magical... It connects me with the world around me. The seeds become part of my family as I steward them year after year, and they get more and more attuned to my taste preferences and ways of doing things. Last edited by joseph; March 1, 2015 at 12:51 AM.

February 28, 2015	#2
KarenO Tomatovillian™ Join Date: Oct 2012 Location: Vancouver Island Posts: 5,931	I save my seed from the best, healthiest most productive plant. I never save seed from weak or diseased plants. Survival of the fittest and genes from the best plant to pass down. My seeds are for my own use or for trading. I do not sell seed. KarenO

February 28, 2015	#4
drew51 Tomatovillian™ Join Date: Dec 2013 Location: Sterling Heights, MI Zone 6a/5b Posts: 1,302	You are assuming too much. Crosses happen and may not show much change, but over time do. Also all genes are not homozygous, just look at Brandywine and all the strains or sub-strains. The hard thing to do is keep a heirloom from changing. I myself don't care if some of mine cross either. I don't isolate blossoms and bees visit mine all the time. Inbreeding is not really a good term, it has more social meaning than anything. Some organisms produce asexually, so talk about inbreeding! I was interested in growing Indian Stripe, it originated from Cherokee Purple. Seemed to grow better, I now have Indian Stripe potato leaf, and Indian Stripe heart, all variations within the same heirloom, no genes are not that stable, everything is a hybrid.

February 28, 2015	#8
frdlturner Tomatovillian™ Join Date: Mar 2011 Location: Galena, MO Posts: 215	So what if I was to plant 4 plants in a square and plant a fifth one in the middle of the 4 would the fifth have a better chance of not crossing since it is in the middle.