Split Tetraploid any Opinions

General Discussion
1

c

2

? R. virginiana X Moderns would produce a split tetraploid (3+1)

I missed it. Where, what’s a split tetraploid and why in the world wouldn’t virginiana, which is tetraploid, obey the standard rules?

3

I was going through some of Hurst’s septet theory. Maybe I should not have bought it up.
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4

Well, can you explain it according to Hurst then?

5

Warren,

I have read everything I can find on Hurst’s “Septet Theory” but cannot see any reason why a cross between two regular tetraploids would give an irregular tetraploid hybrid. In fact, when irregular polyploids are crossed with species that have regularly paired chromosomes, the “Caninae system” tends to break down.
http://bulbnrose.x10.mx/Roses/breeding/Durham.html

Karl

6

Forgive me Don for not using the correct terminology ( Split -unbalanced) does it really matter.