I, too, am interested in this discussion and would like to know if such interdivisional crosses are easier at the 4N level. I am not aware of any tetraploid OA hybrids, but there are some tetraploid LOs, LTs, LAs and OTs I know of:
Chiara VIII LO
Easter Morn VIII LT
El Condor VIII LO
Faith VIII LA
Longicanda VIII LA
Longida VIII LA
Longiklara VIII LA
ML's Ortega VIII OT
Northern Dazzle VIII OT
Pink Champers VIII OOT
Pink Heaven VIII LO
Regal Star VIII OT
Santa Rosa VIII LO
Tanita VIII LO
Tetra Black Beauty VIII OT
Vendella VIII LO
I've been compiling a list of known ploidies here (I also list the source of my information so you can double-check it if you'd like):
Excel:
https://docs.google.com/spread...
PDF:
https://docs.google.com/spread...
