Hybrid Opuntia with Cylindropuntia?

[Charles]

Hello,
Is it possible to cross Opuntia with Cylindropuntia?

Note: this is a great forum. I like the spell check. But how difficult would it be to add the cactus names in the spell check too?

[A. Dean Stock]

I guess there is always a remote possibility but it is likely very difficult, if not impossible) to cross Cylindropuntia with Opuntia. The two groups are actually not as closely related at past taxonomic arrangements suggested. While no direct genetic evidence appears to be available from chromosomal comparisons, it is likely that the two genera have developed quite different sets of chromosomal pericentric inversions and translocations, making them incompatible. DNA sequence comparisons demonstrate considerable differences between the two genera. On the other hand, most of the species within these two genera generally cross freely with other species they contact. This is somewhat less so in Cylindropuntia than in Opuntia.
Dean