120394ns and 2ns: Where We are Now
- Feb 1, 2009Two major findings occurred in deciduous azaleas since 2005.
Dr. Ranney determined that several species thought to be 2ns are in
Dr. Hall determined that the 4ns species share a common ancestor, the
2ns share a common ancestor, and that these ancestors are distinct. In
others words the 2ns form one clade and the 4ns form a second distinct
Now some edges (exceptions) exist. One R. occidentale which is a 2n and
is in the 2n clade has known populations of 4ns. Two R. canadense and
R. molle (most likely) are 2ns but belong to the 4n clade. Three R.
vaseyi a 2n belongs to neither the 2n clade or the 4n clade. Four there
are a few nature hybrids that give the appearance of being crosses
between 2ns and 4ns.
A few people who have done hand crosses have found that 4n members of
the 4n clade and 2n members of the 2n clade simply do not normally
interact to produce fertile offspring but instead normally produce
nothing or infertile 3ns which is consistent with the expected outcome
of crossing 2ns and 4ns based on simple generics.
My point is no matter what you think of the validity of any one of
these findings, the findings from Ranney, Hall, and the people doing
hand crosses support each other.
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