Time for an update on this project as we are a month and a half ahead in time.
I have made a series of attempts at what I described in the above post.
I have varied in several aspects, but never with too many parameters at once.
I rescued ovules at 4 days, 5 days, and 6 days, even though the literature is clearly indicating 5.
The other aspect where I have varied is the amount of MS Medium, the amount of sugar, and agar.
To be completely honest, after trying different things a handful of times without any result, I decided to give in for now.
I am moving to a different apartment in a few weeks/months and wanted to terminate all tobaccos I had growing.
I have a pretty bad flea beetle infestation so I need to rest the soil a bit before moving and setting up again.
That includes discarding the remaining rustica and tabacums for the above experiment.
Even though I did decide to get rid of the plants, I did not yet throw out the petri dishes.
I had not seen any development apart form some mold in a few of them.
But I also couldn't get myself to completely abandon the project just yet.
Today, before going to work, I had a quick look at the petri dishes.
And to my complete surprise, find something "green looking" under the parafilm.
At first I thought it must be some kind of mold developing, but upon closer inspection, we have a single ovule that started developing.
Now of course its very tempting to upon up the dish, but I will refrain from that now.
The medium should have sufficient nutrients to continue to grow for a bit.
I have now placed the dish in a room that has some more indirect sunlight, which should help.
Within the petri dish there is no sign of any contamination, so it should be a safe space for now.
This is very encouraging and unexpected. Will keep you posted!
Below a series of foto's.
* The almost abandoned collection of petri dishes

* The first notion of something green growing inside, hardly visible because of the parafilm

* After pulling away the parafilm, a better visible sprout

* Difficult to see, but it has its first two true leafs and a little root sprouting