This spring I found many diploid pollen grains on one plant of Hawera and three plants of Fairy Chimes. These species hybrids were transformed with Oryzalin from diploids to tetraploids or mixoploids. More information you will find in the PDF file The generation of fertile allotetraploid hybrids of narcissus species by chromosome doubling or on the website ‘www.theo-sanders-daffodils.de‘.
Theo