Squash seed v cucumber seed - floating technique?

[templeton]

Last year someone kindly put me on to the the float technique to separate good (sinkers) from infertile (floaters) cucumber seed. Works a treat. But I've just tried this with some good, mature Uncle Daves Dakota Dessert squash, and they all float.
The squash are a bit small, but properly mature. Are all my seeds infertile, or are floaters still viable? I've never really tried seed saving with squash before

T

[Drahkk]

The seed I saved from a Galeau d'Eyesines pumpkin and a Juan Canary melon last fall did the same thing. 100% floaters. I cracked open a few, and most seemed to be perfectly formed seeds that just had an air bubble inside the seed coat. I can't say for sure as I haven't replanted yet, but I'm guessing that if that an open cavity forms before the seed coats harden they can trap a gas bubble, making them float. Anyone with more knowledge and experience, please feel free to correct me.

MB

[Joseph Lofthouse]

The float technique works on Pepo and Moschata squash, but it doesn't work reliably on Maxima squash because the seed coat tends to be corky-like. Uncle Dave's Dakota Dessert squash is a Maxima squash.

You might get some separation if you try winnowing the dry seeds.

[templeton]

thanks for the info. Continue to be amazed (and thankful) at the knowledge base here.
T

[YoungAllotmenteer]

I did the sink swim test last year on a Buttercup squash' seed if I remember correctly. It seemed to work well, the ones that floated were hollow, sure may have lost the odd fertile seed but seemed a very good indicator for that seed.

[raymondo]

For very small numbers of maxima seeds, I use the 'squeeze-it-between-my-fingers' test. If it feels like there's an embryo within, I keep it. Otherwise, it's compost!

[templeton]

Tried a second squash, from my other UDDD plants, and the sink test or rather, neutral bouyancy test worked - and they were decidedly plumper than the first fruit.
So I've got some.
T

[bertiefox]

Would the sink or float method work with evaluating melon seed? I have quite a lot of fairly old seed, and as I'm still waiting for some of it to germinate I wonder if it is still viable. If anyone has used this for melons, I'd be interested to know.

[raymondo]

I use it on freshly harvested melon seeds and keep only the sinkers. Lots float and I'm sure there are viable seeds in among the floaters but I usually get some sinkers so I go with those. I haven't tried it on old seed to test for viability. A trick I have used on old melon seed is to (very) carefully crack open the outer shell and try to peel away what I can. Sometimes old embryos are very weak and they have a hard time forcing open their protective casing.

[flowerbug]

if i did the floating method for the melon seeds i have been getting this year i think i'd be discarding nearly 100%. winnowing once the seeds are dried well may be a better approach. at the moment i'm waiting for seeds to dry down all the way because i accidentally put seeds in a plastic container before they were fully dry and they started to mold. i think i caught it in time and washed and lightly bleached the seeds and will dry them much more now before i put them into a more sealed container.

one way of finding the hollow seeds in the melon is to drop them on a thin plastic tray and to listen to the sound they make. also sometimes dropping them in piles the ones that are more empty will roll off to the side further. you can also see through some seeds that are empty. sometimes the empty seeds will stick to your hands more than the full ones. etc. i've been finding all sorts of things out the past few weeks as i learn about how to grow these melons.

[xdrix]

I try to sow all the seeds formed and mal formed. Sometimes i have a seed malformed who germinate!
For me the floatted technique is not fiable.
I see the majority of the seeds able to germinate at the eye.
But i put the seeds malformed at an other placement than the seeds well formed.

[flowerbug]

i have way too many seeds to do that, i'll probably plant a dozen seeds next year and thin them down to two or three plants. i have about a liter of seeds already. plenty to give away.

[zeedman]

When using the float method for anything, I always stir the seeds very briskly with a wire whisk. This helps to knock away any clinging membranes, which can trap air bubbles - especially for cucurbits. For cucumbers & melons, I collect as much juice with the seeds as possible, and ferment the mixture for 2-3 days (same as for tomato seed). Fermentation helps to loosen the membranes, after which the stir & sink method works more reliably. Watch carefully, and immediately remove & dry the seeds if there is any sign of germination (which happened to me once with cucumber seed).

The float method is only effect when processing wet seed (seed from a fleshy fruit) immediately after removal. I would not recommend it for testing dry seed. Dry seed would need to re-absorb moisture before it could sink, by which point it would probably begin to germinate.

Freshly harvested squash seed may need to soak briefly before some of the good seeds sink, I observed that in my Tromboncino this year. As long as a good quantity of seed sinks, I am not concerned about any good seeds which may still float. Some references claim that the fermentation method can be used for squash seeds, but I have not tried that.

[flowerbug]

i like the dry method i use for squash seeds that have a slippery coat on the seeds. just squeeze them out of the flesh as much as possible and dry completely and then when dry you can rub the seeds to remove the shiny coat that is left. i just finished up some kabocha seeds a few minutes ago. no fuss, no waste of water, no smell of fermenting or results of that do deal with. just have to wait until they dry enough.

[zeedman]

I do the same thing, rubbing the dry seeds out of their "skins" and winnowing away the debris. The dry method works well for C. maxima (kabocha, hubbard, banana, buttercup, etc.) which is a good thing, since the float method works poorly for seeds of that species.