Proper plant population for seed preservation

[ottawagardener]

Real Seeds is a great link for info by the way as well as what looks like a great seed company.

[sandbar]

Hi Telsing ... am a little late in responding to your post ...

Do you have a link to "Real Seeds"?

A Google search for "real seeds" produced some interesting results ...

Thanks,
Steve.

[spacecase0]

is this it ?
www.realseeds.co.uk/

[canadamike]

yep space, this is it...

[honeydew]

I have read Seed to Seed (and re-read) and am currently reading Breed Your Own Vegetables, and if I get this right, say with squash, you can save from 1 or 2 plants, but ideally save from more to maintain a wider set of genes in your seeds.

That's what I got out of what was said here too. So, if I continue to get this right, you have two options:

1. Grow several plants and save from many plants, or
2. Grow what you can in your limited space, and save seed, but also use your original seed stock and grow out and save seed the following year too, thus increasing the genetics in your saved seed stock.

Do I have this right?

Ok, so apparently squash is unique in that even being an outbreeder, it doesn't really suffer from inbreeding depression. Does this apply to all squash - summer and winter?

Cucumbers and melons are the same - don't really suffer from inbreeding depression, correct?

I've also heard two schools of thought - one being that you make sure you have a minimum population of plants, and one being that you save seed from several fruits on less plants (say six fruit on six plants as opposed to a minimum of 20 plants).

Are both ways acceptable?

So if I have only 9 seeds left from a cucumber I want to save seed from, can I safely do it, saving seed from multiple fruit on as many plants as I select out? What should be the minimum plants I select?

[Joseph Lofthouse]

My strategy for the Charleston Gray watermelon that my family has been growing for decades is:

Collect all of the seeds from 4-6 great melons wherever they happen to come from in the patch. Add to that whatever seeds happens to get captured while eating melons for a meal. Swap seeds with my father that also grows this variety. These collected seeds become my main seed stock for the following year. So maybe 30 fruits are represented. I'm sure not going to engage in vine tracing to see if two fruits come from the same plant.

At planting time I include some 2 year old seed, some 3 year old seed, and once in a while a few seeds from other people that also grow this variety. So after all that the seeds of around 100 fruits may be represented in my planting.

To maintain diversity it's mathematically better to save from more plants than from more fruits on a limited number of plants. (Cousins are usually more diverse than half-siblings.)

I have no experience with inbreeding depression in anything... Don't know how it works or how it doesn't work. It's not something that I have tried to observe in my garden.

Go ahead and plant the cucumber seeds... If the offspring start growing poorly after a few generations then add some pollen from another variety. I grow land-races of everything I can possibly grow a land-race for. Never have to worry about inbreeding depression that way.

[sandbar]

Joseph, then are you only planting one variety of watermelon each year?

[Joseph Lofthouse]

Last year I grew two varieties of watermelon. Each in a different town.

The way I figure pollination, is that it essentially operates on an inverse square law, or even an inverse cube law, meaning for all intents and purposes that a plant is incredibly more likely to be pollinated by itself, or by it's closest neighbor than it is to be pollinated by the plant at the end of the row. So by the time I get to 100 feet of separation, I figure that even for extremely out-crossing plants that for all practical purposes I am growing isolated populations even if they are planted in the same field.

I grow in 3 huge fields, and also in a number of smaller isolation gardens so I have plenty of options for doing traditional isolation if I want to. I'm finding that less desirable all the time. (Don't let lack of garden space stop you from breeding your perfect variety. People are eager to participate in a breeding program.)

The cantaloupe land-race that I have been working on the last two years was so successful that this year I intend to create a watermelon land-race. I'll be planting around a hundred varieties of watermelon including three land-races and we'll see if any of the individual plants grow as well or better than what I have been growing. By the second or third year I will likely stop growing my traditional watermelons.

[MikeH]

It took a bit of digging to find a home for this. I've just come across an online version of Steve Solomon's Gardening When It Counts: Growing Food in Hard Times. By way of background, Solomon founded Territorial Seed Company.

It's loaded with lots of unusual commentary. Given his experience during his Territorial Seeds days, I'm inclined to listen and have ordered his book.

With regard to squash, he says:


Aside from planting fresh each year from the original seed packet, can I not keep genetic diversity for a long time by crossing saved seed with original seed and saving it (assuming that the starting package of seeds is genetically diverse)? I'm not attempting to breed but rather keep output up without having to constantly be dependent on buying seeds.

Regards,
Mike

[oxbowfarm]

I have to say that I have not seen remotely the same thing when growing winter squash. I have never noted any inbreeding depression effect so far, and I am more than a few generations in. I have never even come close to 25 plants of any one variety either. I'd try it and see how far you get, just because someone says it in a book doesn't mean its true. Not trying to knock Mr. Solomon, I've heard good and bad reviews of that book. I'm sure there is some good stuff to be gained from it.

[MikeH]

I'm sure that Solomon gets good and bad reviews. ;D




I often wonder how much of one's gardening expertise is a function of where one lives. What works/doesn't work for me may not work/work for you simply because we live in two different places and have different conditions. Obviously, there are some constants but there are a helluva lot of variables. I think I'll hedge my bets by buying seeds each year as a fallback in case my saved seeds lose vigour.

Regards,
Mike

[oxbowfarm]

I think the best thing to do with gardening (perhaps all of life) is to scrupulously avoid all dogma. I've read and own a lot of gardening and farming books (although I don't own Mr. Solomon's yet). They all usually have something in them that will look like dogma, but it probably does work at least for them in their micro-climate where they garden or farm. Otherwise I'd hope they wouldn't print it. But one thing I've noticed a lot of especially in gardening books is that stuff gets reprinted as received wisdom when I've found the opposite to be true. Especially in regards to transplanting, I've read how this or that crop "cannot be transplanted" when in my experience almost every crop can quite easily be with minimal care.

[Joseph Lofthouse]

Nov 19, 2011 6:40:09 GMT -5 MikeH said:

Aside from planting fresh each year from the original seed packet, can I not keep genetic diversity for a long time by crossing saved seed with original seed and saving it (assuming that the starting package of seeds is genetically diverse)? I'm not attempting to breed but rather keep output up without having to constantly be dependent on buying seeds.

My strategy, rather than buying fresh seeds, is to swap seeds with the neighbors that are also growing the same variety. That keeps the local adaptation strong, and it widens the genetic base of our crop. I'm generally not opposed to planting seeds from a packet, because they also may widen the genetic base, but I've never had a problem with inbreeding depression in any crop that I've grown. I wonder if it's another of those myths propagated by The Corporation in order to frighten people into buying fresh seeds every year, or in this case at least every other year....

[castanea]

I'm not even sure that some of these people are experiencing inbreeding problems. If you keep planting squash on the same land year after year, you're going to deplete some nutrients in the soil and your squash will do more poorly every year. This is true even if you fertilize with N, P and K. Watermelon growers are very aware of this. I've seen corn growers plant corn every year for 10 years and use only N, P and K fertilizers. Eventually when they have problems they realize that the soil is "played out".

[castanea]

Nov 19, 2011 7:42:23 GMT -5 oxbowfarm said:

I think the best thing to do with gardening (perhaps all of life) is to scrupulously avoid all dogma. I've read and own a lot of gardening and farming books (although I don't own Mr. Solomon's yet). They all usually have something in them that will look like dogma, but it probably does work at least for them in their micro-climate where they garden or farm. Otherwise I'd hope they wouldn't print it. But one thing I've noticed a lot of especially in gardening books is that stuff gets reprinted as received wisdom when I've found the opposite to be true. Especially in regards to transplanting, I've read how this or that crop "cannot be transplanted" when in my experience almost every crop can quite easily be with minimal care.

I think that some people are poor observers. Others may observe well generally speaking but because of preconceived ideas ignore some things and tend toward preconceived notions. Part of my appreciation for Luther Burbank arises out of his ability to observe very well and to be disinclined toward preconceived ideas.

I've read Solomon and while I appreciate many things he says, I suspect he has many preconceived ideas and looks for evidence to confirm those ideas. That leads him astray occasionally.