Bernard, it looks like you are off to a good start.
Some others are threaten by fungi, esp. the cotyledons, particular the damaged areas
I have had success eradicating this type of white fungus using tebuconazole (Bayer Advanced 3-in-1) at the standard rate of application. Just mix up a small amount and apply it with a spoon to wet the seedling, repeat after a week.
I usually wait two or three weeks before transplanting the seedlings into soil. This gives time for the roots to form.
Don’t give up. Es ist noch kein Meister Vom Himmel gefallen.
Why are some of your embryos stained yellow (are you applying fungicide to them)?
George, I’ve no fungicede used. It was the only one germ with this pale yellow colour. I was first assuming that it is possibly an albino. Later, when exploring it closer I found a kind of skin covering the embryo, maybe a part of the inner testa ? But it was still to late (morituri te salutant)
Don, thank you for your recipe. Your German is great!
I just realised that in your first photo (on your blog) there is a cotyledon part with no radicle that you seem to have included in the culture. I would personally not include this, as it will only ever die, and will cause fungus in the culture.