longevity of seeds

[Hellmanns]

Originally Posted by carolyn137

Sorry but there is no 1/2 life for tomato seed.

The oldest tomato seeds that were ever germinated and documented, which is important, were 50 years old and that happened when the precursor to the USDA station in Ames, IA opened and the Cheyenne, WY place had to send all their seeds to Ames, IA where germination testing was done.

And the seeds in Cheyenne were stored in regular filing cabinets at ambient temps. Nothing special,

The oldest tomato seed I ever was able to wake up were seeds of September Dawn which were 22 yo, but then I had to use special methods to wake up seed even younger than that since seeds of heart varieties, for instance, do not have the same longevity as non hearts do.

Hope that helps,

Carolyn

Respectfully, Carolyn,
I do know that heat and moisture destroy germination rates but, I did read exactly what I said, "Somewhere" over the years that tomato seed have a half-life and that was 100 years. It was not read on the internet, it was in a garden magazine, book, seed catalog, or publication many years ago. Now that I am thinking about it, it could have been a publication on preparing seed for long term storage, or, that seed have a half-life when properly stored? Did Jeff McCormack write such an article?

The seed I germinated were properly stored by ME in 1989. If my math is right, that makes them 26 years old. They were the last of 4 varieties to germinate this spring by 3 days, but when they started they were all up within 24 hours with no helmet heads, or weak seedlings! They were fermented, then dried to very low moisture via color indicating silica gel and sealed in heat-seal foil packets, and were stored in the freezer.

[carolyn137]

Originally Posted by Hellmanns

Respectfully, Carolyn,
I do know that heat and moisture destroy germination rates but, I did read exactly what I said, "Somewhere" over the years that tomato seed have a half-life and that was 100 years. It was not read on the internet, it was in a garden magazine, book, seed catalog, or publication many years ago. Now that I am thinking about it, it could have been a publication on preparing seed for long term storage, or, that seed have a half-life when properly stored? Did Jeff McCormack write such an article?

The seed I germinated were properly stored by ME in 1989. If my math is right, that makes them 26 years old. They were the last of 4 varieties to germinate this spring by 3 days, but when they started they were all up within 24 hours with no helmet heads, or weak seedlings! They were fermented, then dried to very low moisture via color indicating silica gel and sealed in heat-seal foil packets, and were stored in the freezer.

Jeff McCormack wrote two articles about saving seed and yes, I know Jeff very well, one of those articles is still at SASE and I have it in my faves. The other one he wrote he did so b'c he got a grant to write several articles, one of which was about tomatoes and pretty much the same as what he wrote for SSE about NCP ( natural cross pollination), etc.

No, Jeff never said anything about half life of tomato seeds.

Half life refers to the time it takes for radioactive decay to occur, and here's a link explaining that:

https://www.google.com/?gws_rd=ssl#q...+and+half+life

If half life referred to tomato seeds it would mean that starting from zero, all seeds germinate, that after 100 years only half of them would.

I don't know about you but I know I'm not going to live that long, being 76 right now.

Carolyn

[Tormato]

At five years, I sometimes do start to run into problems. It can take seeds much longer to germinate, and some seedlings turn up headless. Storage in a cool dry place will likely help reduce any problems.

[rwsacto]

A bit beyond the subject, but I found this article intriguing.

http://phenomena.nationalgeographic....tes-and-nazis/

Rick

[Hellmanns]

Originally Posted by carolyn137

Jeff McCormack wrote two articles about saving seed and yes, I know Jeff very well, one of those articles is still at SASE and I have it in my faves. The other one he wrote he did so b'c he got a grant to write several articles, one of which was about tomatoes and pretty much the same as what he wrote for SSE about NCP ( natural cross pollination), etc.

No, Jeff never said anything about half life of tomato seeds.

Half life refers to the time it takes for radioactive decay to occur, and here's a link explaining that:

https://www.google.com/?gws_rd=ssl#q...+and+half+life

If half life referred to tomato seeds it would mean that starting from zero, all seeds germinate, that after 100 years only half of them would.

I don't know about you but I know I'm not going to live that long, being 76 right now.

Carolyn

Carolyn, and again, respectfully..
I know that most educated people think the term half-life refers to the exponential decay that radioactive material undergoes where the decay is constant over the whole life of the decay process. But, the term half-life can also be used for non-exponential decay processes, just as the unknown author of the article I read about preserving the germination rate of tomato seeds did many years ago. Even though the decay rate varies in non-exponential decay. I even noted in the link you provided that you used the search terms "radioactivity" along with "half life", when just the term "half-life" would have been sufficient.

[carolyn137]

Originally Posted by Hellmanns

Carolyn, and again, respectfully..
I know that most educated people think the term half-life refers to the exponential decay that radioactive material undergoes where the half-life is constant over the whole life of the decay process. But, the term half-life can also be used for non-exponential decay processes, just as the unknown author of the article I read about preserving the germination tomato seeds did many years ago. Even though the decay rate varies in non-exponential decay. I even noted in the link you provided that you used the search terms "radioactivity" along with "half life", when just the term "half-life" would have been sufficient.

Yes, I did do the word half life with the Google search as you can see.If I do a Google search just using the words half life as you suggest, this is what I get

https://www.google.com/?gws_rd=ssl#q=half+life

I think it's time for us to agree to disagree.

Carolyn

[Hellmanns]

Originally Posted by carolyn137

Yes, I did do the word half life with the Google search as you can see.If I do a Google search just using the words half life as you suggest, this is what I get

https://www.google.com/?gws_rd=ssl#q=half+life

I think it's time for us to agree to disagree.

Carolyn

Your right, Carolyn, I think it's time for us to agree to disagree, though Wikipedia explains Half-life in non-exponential decay pretty well..

[Worth1]

https://www.google.com/url?sa=t&rct=...Zoz_XWxZ_mhO2Q