The Tropical Fruit Forum

The precocious flowering of yuzu seeds have been known for quite some time.

See..... Precocious flowering of Citrus seedlings and its use for determination of cultivars generating male sterile progeny

Thank you for posting the video of this tree. It is amazing, and the scientist seem to be very  egger about the possibilities that this tree  could provide additional information concerning greening.

NapAp22,  that Kishu is not my tree, it is Brian tree.  He does a fantastic job with his citrus trees.

The internal eatable part of the fruit should still be fine.

A citrus fruit can have up to 6 seeds and still be sold as "seedless" in the United States. This is based on USDA regulations.  I don't know about Europe's regulations, or if they even have regulations on seed content.  Your Nordmann was probably a correct variety.

I agree with  Galatians522 that it is rust mite damage.  Spray with soapy water, or a horticultural oil or neem.

Ideal pH for citrus growing medium is 6.5.   However, any  soil between 6 and7 should be fine.  Just be sure to be under 8.

Dosen't look like mites or thrips to me.  Looks to be leaf fungal diseases

I am confused why so many people have such a difficult time controlling spider mites.   For me,  a strong water spray once or twice gives excellent control.

I think it also has fertilizer issues.  Organic fertilizers do not work well in container grown trees, as there is not enough micro organisms to brake  down organic fertilizers into a usable forum.  Also, using an excellent fertilizer like Jacks once (a month ago) is also not a proper fertilizer schedule.

Yes, the higher up on the tree the twig will have a higher node count to start it out.

Yes you can repot when fruit are present.

Clearly looks  like it just comes from the rootstock.