Asplenium scolopendrium: spore seedlings

[Véronique Macrelle]

I picked a leaf with sori, left it a week in an envelope to dry: the spores fell in the envelope, then I sowed on hot potting soil: prothalles germinate in 2 weeks, but grow very slowly.
 currently the prothalles are 3 months old and the blades are 5 mm wide.

[Véronique Macrelle]

that's it, there was fertilization! baby ferns are starting to develop.

I send a mist of water a few times to wet the surfaces of the prothalles. (male gametes swim in water)

and a first little fern leaf appears! top right, it is 5 mm wide and 1 cm high.

on the magnification we see:
a crater, no doubt, the place of fertilization.
we can clearly see 3 fern shoots around.

[Anders]

Hi Veronique

Great and inspiring fotos. Picked a few leaves of A. rute-muraria and A. trichomanes this morning to try to germinate the spores.

Anders

[Véronique Macrelle]

thank you Anders

this is how i installed the fern spores

[Carolyn]

Anders,

I am not a fern expert, but I have grown a few ferns from spores. I think you will find that the spores are ripe in late summer - do correct me if I am wrong! Here are some photos of my attempts from early last September.

1.  Adiantum pedatum has made a good potful. I will let these get slightly bigger and then pot them up. They have spent the winter enclosed in a plastic bag on a shady windowsill.
2.  Sphenomeris chinensis BSWJ6108 - I am hopeful that this is what is growing. It always starts by looking like an unpromising mass of liverwort! Sown 8th Sept 2019
3.  Athyrium vidallii, sown 29th Aug 2019

[ruweiss]

Amazing to watch growing ferns from spores

[Véronique Macrelle]

Carolyn
you are more expert than me! it is successful ..
because I’m doing this for the first time.

now that i see prothalles and small leaves, i'm proud, but i didn't know if it would work ...

and transplanting, is there a method, a period?

Anders
put your leaves to dry for a few days in an envelope, you will see if spores still fall from it ... it must be like dust ...

[Carolyn]

Veronique,
I just wait till the little plants are big enough to handle (maybe 1 - 2cm tall?) then transplant them to small pots with ordinary multi-purpose compost. I keep them wet and shady - enclosed in a plastic bag for a while. Et voila!

i have no idea whether this is the best procedure, but it seems to work!

[Anders]

Carolyn, you are right. Only empty sporangia on A. trichomanes. But there were still a bit of spores left in the sporangia on A. rute-muraria  and A. scolopendrium. I wonder if they can be crossed if I mix the spores in one of the pots.

Anders

[Carolyn]

Anders,
Interesting that you still found some spores - I wonder how long they remain viable? I have no idea of the answer to your query about crossing. We need a fern expert! Anyone?

[annew]

I think the usual method for hybridising ferns is to sow the spores together, then make sure the prothalli are kept at high humidity (enclosed in a polythene bag) this is to make sure that there is a film of moisture for the male gametes to swim through. If the male (antheridia) and female (archegonia) structures are studied with a hand lens or microscope it can be seen when they become ripe, then the pot can be submerged in warm water, so that the water level just rises through the prothallus mat. This makes it easier for the sperm cells to swim from one species' prothallus to that of the other species.
It is worth noting that if prothalli are very crowded, they will not produce sexual organs, so if you have sown very thickly you will need to 'patch out' small sections of the mat onto fresh sterilised compost, leaving space between them, then place again in a bag or box. This will often induce production of the sexual organs. Keep the young plants with fronds in the closed plastic bag/box for a while then when they look ready to pot on, gradually open up the bag over 2-3 weeks to get the plants ready to take the lower humidity outside.
Good luck!

[Maggi Young]

As if by  magic, one  of  our  fern experts  appears - thank you  Anne! 

[annew]

As if by  magic, one  of  our  fern experts  appears - thank you  Anne! 

The magic that is Maggi Young 

[Véronique Macrelle]

again i try to sow fern spores.

but it is long to come. on 7 species sown at the end of October/beginning of November, only 3 seem to germinate since 1 week:
Dryopteris sieboldii
Dryopteris wallichiana
and maybe the beginning of Coniogramme emeiensis... the latter only makes a few spores at a time under its leaves. we can't even really see a sporangium... with a magnifying glass some spores seem to pearl out of the leaves..., spread out in time. strange.

in short, 2 to 3 months for germination at 15/18 °C, seems like a long time! it should be warmer?

 today, i discovered spores of Woodwardia ungemminata on the old unfrozen leaves. it's the first year that it makes me some.


 I sow and I think maybe the emergence could be accelerated by misting to stick the spores to the substrate?

How do you do it? At what temperature?

I know this post goes back a long way, but Anders, did you get results with your "slightly old" spore seedlings?

Translated with www.DeepL.com/Translator (free version)

[Carolyn]

Patience, Veronique, I think your remaining spores may germinate in the next 2 or 3 months. I keep mine cool (maybe 15 - 16C) and moist and wait…..