Fun Fact: Seeds with no seed coat

[Nan_PA_6b]

I was cleaning seeds a bit too enthusiastically and rubbed the seed coat off of two of them. I planted the two which had no seed coat and they sprouted exactly the same as the rest of the seeds.

I don't recommend it, as I'm sure the seed is vulnerable without the coat, but you can be sure you won't get helmet heads!

Nan

[ginger2778]

That's pretty interesting.I just learned.

[ContainerTed]

Now that's just weird. It is also an "AHA" moment. But I think missing or damaged seed coats should be planted ASAP or the germ plasm will dry out and quickly die.

[Nan_PA_6b]

Originally Posted by ContainerTed

But I think missing or damaged seed coats should be planted ASAP or the germ plasm will dry out and quickly die.

I planted them immediately after rinsing.

Ted, we go to such lengths to dry our seeds, do you really think drying coatless seeds would do them in?

I sense a scientific experiment coming on...

Nan

[carolyn137]

Originally Posted by Nan_PA_6b

I planted them immediately after rinsing.

Ted, we go to such lengths to dry our seeds, do you really think drying coatless seeds would do them in?

I sense a scientific experiment coming on...

Nan

Ted, I'm not, but first, how do you clean tomato seeds such that you rub off all the outer coats and yes there is more than one coat.?

And yes,if that did happen you would expose the embryo, and that's not good at all IMO, and yes,IMO if you dried the embryos,pffftt, there they go as in RIP.

Carolyn, who forgot the link

https://www.google.com/search?hl=en&....0.eA4qmTmB9_A

[Nan_PA_6b]

Originally Posted by carolyn137

Ted, I'm not, but first, how do you clean tomato seeds such that you rub off all the outer coats and yes there is more than one coat.?

I was rubbing the seeds against the fine mesh of a strainer. I wasn't doing it that hard. It really surprised me that the coats rubbed off as easily as they did. Maybe they were defective?

Nan

[carolyn137]

Originally Posted by Nan_PA_6b

I was rubbing the seeds against the fine mesh of a strainer. I wasn't doing it that hard. It really surprised me that the coats rubbed off as easily as they did. Maybe they were defective?

Nan

Yes, I know that there are some who rub the seeds in a strainer, and some use oxidative methods as well, but for the oxidative methods no one I know, including me,has ever found any data to indicate that that helps.

I'm one of many who always used fermentation since it's gentle, doesn't destroy seeds at all if done correctly, and the heart varieties especially have few seeds and I wanted every single seed I could get for both my SSE listings at the time as well as for seed offers.

Thank,for getting back to me,

Carolyn

I ferment all of mine as well ( learned from you and Craig, I believe, Carolyn - thank you for sharing!) but then they all go through the mesh scrub once they're done, and I've never noticed any coats coming off - that's very interesting Nan, and cool that you thought to plant them, too!

Does the outer coat contain any nutrients or perform any other function other than protection? And I gather from Carolyn's post that there are more than one (several?) coat? Always something new to learn!

[ginger2778]

I found this about the tomato and pepper seed anatomy. Didn't know the seed coat was called the testa until today. This shows only a seed coat, but not the layers I am looking for to learn. http://www.seedbiology.de/structure.asp#pepper1

Carolyn, can you find a better link showing the layers of seed coat, I think many of us want to learn.

Thanks Marsha!

Here's another link: http://horticulture.oregonstate.edu/...oresearch.html

So it seems that certain enzymes are needed to break through the endosperm, particularly the micropylar region which is the endosperm cap near the radicle. I don't see anything about more than one coat here, but it is noted that the endosperm is quite hard so perhaps that is what Carolyn meant? Outside the endosperm is the testa as you mention, Marsha. Very interesting stuff, tomatoes!

I wonder if those enzymes weren't even necessary in your case, Nan, since you scrubbed those (defective?) coat(s) right off?

Hmmm...

[Nan_PA_6b]

I clicked on Carol's link and from there went off on a search about weak seed coats. This link & others:
https://books.google.com/books?id=IM...tomato&f=false
talk about one of the wilty genes "sitw" which makes tomato seeds have a very thin (1 cell thick as opposed to 3-4 cells thick) testa. Such seeds have reduced Abscisic acid, something that inhibits germination.

These seeds' female parent was Anna Maria's Heart, which in addition to being wispy, was also oddly wilty. And the seeds did germinate quickly.

Nan

Originally Posted by MdTNGrdner

Here's another link: http://horticulture.oregonstate.edu/...oresearch.html

So it seems that certain enzymes are needed to break through the endosperm, particularly the micropylar region which is the endosperm cap near the radicle. I don't see anything about more than one coat here, but it is noted that the endosperm is quite hard so perhaps that is what Carolyn meant? Outside the endosperm is the testa as you mention, Marsha. Very interesting stuff, tomatoes!

I wonder if those enzymes weren't even necessary in your case, Nan, since you scrubbed those (defective?) coat(s) right off?

Hmmm...

Good find, Nan! So the immediate, practical takeaway is "no scrubbing seeds of wilt-type tomatoes"!
(Unless, of course, you wanted to experiment! )

[Nan_PA_6b]

Originally Posted by MdTNGrdner

Good find, Nan! So the immediate, practical takeaway is "no scrubbing seeds of wilt-type tomatoes"!

Yes! Although it's probably not something most folks have to worry about, because wilty and wispy are two different things. There are several different genes that cause a plant to show an increase in wilting of leaves under stress. (ref: https://www.ncbi.nlm.nih.gov/pmc/art...00627-0198.pdf ) It's not the same as the genes that make a heart or paste, for example, wispy. I think Carolyn has made this point before.

(Unless, of course, you wanted to experiment! )

I was sooo tempted to scrub away and get a bunch of bare-nekked seeds to experiment on, except the seeds in question were a limited number, of a deliberate cross I'd made. I do hope the resulting new variety won't have a problem with weak seed coats!

Nan

[carolyn137]

Originally Posted by ginger2778

I found this about the tomato and pepper seed anatomy. Didn't know the seed coat was called the testa until today. This shows only a seed coat, but not the layers I am looking for to learn. http://www.seedbiology.de/structure.asp#pepper1

Carolyn, can you find a better link showing the layers of seed coat, I think many of us want to learn.

Marsha, I went on a Google search last night and yes, I found several links to show the anatomy of a tomato seed,the importance of nitrate ion in priming a seed to develop and germinate,etc,but I think others below have given similar links, but I won't know until I have the time to read them.

Carolyn