No one is saying that the information in the Flora of North America is wrong. I was just making a point of semantics that even though a species had an ancient hybrid origin, at some point we no longer call it a hybrid but use the term species.
"Sean A. Zera" <zera@umich.edu>
Re: [iris-species] I. versicolor
Apparently I can't trust the Flora of North America at efloras.org,
which states "E. Anderson (1936) showed rather conclusively that Iris
versicolor arose as an amphidiploid between I. virginica (n = 35) and
I. hookeri (I. setosa var. canadensis) (n = 19)." Needless to say,
though, I wasn't just making that up.
Having just checked the reference, Anderson actually described var.
interior because only plants from that region of Alaska fit his
careful morphological predictions of what the setosa parent of
versicolor should look like.
Anderson points out that allopolyploidy explains why there are no
albino versicolors. I. virginica is already an ancient tetraploid, so
in order to be albino both sets of chromosomes must possess the
mutation. It's even worse for versicolor, which has three sets of
ancestral chromosomes.
Sean Z
Quoting Robert Pries <r*@embarqmail.com>:
> Iris virginica is not a hybrid. It is a species of hybrid origin.
> That origi n is believed to have occured ten thousand years ago
> during the last ice age. The parent was not hookeri but Iris se tosa
> interior whose range was pushed south by the ice sheet. The
> researcher who i nvestigated this was Edgar Anderson director of the
> Missouri Botanical Gardens and most of his papers on this are found
> published in the Missouri Botanical Gardens A nnals. Anderson was a
> great friend of the Iris Society and h ad an iris test garden at
> MoBot. He was also the author of Iris xrobusta which IS a hybrid as
> denoted by the x in its name. R obusta is a fairly commonly grown
> plant with several selected cultivars, Gerald Darby being one of the
> best known. Nature is constantly evolving but generally species are
> no longer considered hybrids after having found a niuche in the
> natural world for thousands of years. Many Irises like the Pacific
> Coast Natives are still in the process of speciation. Some authors
> would say that all the more or less 10 species of PCN are all one
> species that is constantly separating and coming together. O thers
> sort out the 10 species and note that perhaps as many plants growing
> in this region are hybrids as there are pure species. N ature does
> not have semantics that is a human invention.
>
> ----- Original Message -----
> From: "Sean A. Zera" <z*@umich.edu>
> To: i*@yahoogroups.com
> Sent: Thursday, October 6, 2011 9:51:50 AM
> Subject: Re: [iris-species] I. versicolor 'Murrayana'
>
>
>
>
>
>
> I believe the current assumption is that versicolor is a hybrid
> between virginica and hookeri (a.k.a. setosa v. canadensis). Not
> counting hookeri, the nearest setosa is in southern Alaska, thousands
> of miles away from versicolor or virginica.
>
> Since virginica and versicolor (and probably Ãrobusta) are mixed up or
> simply not distinguished in the nursery trade, and are planted in
> large numbers in wetland mitigations and restorations, I'd be
> surprised if there aren't lots of populations established outside
> their original ranges.
>
> Sean Z
>
> Quoting Chuck Chapman < i*@aim.com >:
>
>> I just looked at article on Murrayana.
>>
>> Very interesting.
>>
>> A couple of observations. The offspring of Murrayana X vesicolor
>> sound very much like offspring of crosses of virginica x versicolor
>> Except that the "Robusta" plants are usually fertile.
>>
>> Also versicolor were produced from a natural cross of setosa x
>> virginica. And hokerii is very closely related to setosa. Hookeri
>> and versicolor are both native to Newfoundland.
>>
>> I found Cast Ashore (a robusta) in an area that has versicolor but
>> no virginica. so you can have plant relics or hybrid relics in
>> strange locations.
>>
>> Chuck Chapman
>>
>> Sometimes
>>
>>
>>
>>
>>
>> -----Original Message-----
>> From: Eleanor Hutchison < e*@mymts.net >
>> To: iris-species < i*@yahoogroups.com >
>> Sent: Wed, Oct 5, 2011 10:31 pm
>> Subject: [iris-species] I. versicolor 'Murrayana'
>>
>>
>> Todd, I rec'd this iris today, so looked up a bit more information
>> about it and came across your interesting article at Dave's Garden,
>> "The Story of Iris versicolor 'Murrayana'".
>>
>> I hope I planted it at the correct depth, as it had roots heading
>> up one of the stems.
>>
>> El, Ste Anne, Manitoba, Canada
>>
>>
>>
>>
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>>
>>
>
>
>
