Re: 'Tid-bit' - I. pallida cengialtii?

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Been away for a few days.  Playing catch-up again.

 

Some of this is probably obvious and not anything new for many of you, but here'goes anyway.

 

No such thing as a dumb question (well, maybe I've heard a few, but rarely one out of genuine curiosity).

 

Due to science fiction usage, all the media hype about cloned sheep, and so on, the definition of "clone" in many people's mind has been twisted slightly off kilter.  Yes if you grow a new human by cutting off part of another, the new individual would be a "clone", but in the sense most botanists use the word, the original and the copies would represent the same clone (as would identical twins).  The main qualifications is that they are genetically the same, from the same pair of original gametes. 

 

When I say clone in relation to plants, I mean a group of plants derived from a single seed.  Any plants vegetatively propagated from a plant originally from a single seed are the same clone.  [[Rare exception: sometimes there are seeds that enclose twins, which produce two plants, not necessarily identical twins.  Technically if they are identical twins, they would still be the same clone, but not if they are paternal twins derived from separate male gametes.]]  Nearly all registered Iris cultivars are single clones, but so is any vegetatively reproduced individual of any pure species  (i.e. all plants of I. pallida cengialtii Loppio' are a single clone, but all individuals of I. pallida cengialtii are not). 

 

For all practical purposes, a clone is to a botanist as is a cultivar to a horticulturalist (but the definition of a cultivar is sometimes a bit looser).

 

There are also single clones that are actually registered as more than one cultivar.  Most examples of this involve a sport that is registered as a new cultivar.  Even though it looks different, it is still the same clone as the original, in many cases the sport can even revert back to the original form again.  Thus, 'Madonna' is the same clone as 'Albicans', even though it is a different color and registered with a different cultivar name; same thing for 'Florentina' and 'Elsie Crouch Diltz'; 'May Allison' is the same clone as 'Celeste'; same for 'Beverly Sills' and 'Beverly in White'; and so on.

 

My suspicion that 'Tid Bit' is a clone of I. pallida cengialtii is based on the morphology of it's offspring.  Since I haven't actually seen the plant itself, I am only making (I think) an educated guess.  I might be wrong (but I'll bet it has I. pallida cengialtii as a strong part of its background, even if it isn't pure).  The photo Laetitia sent actually reminds me a lot of I. pallida "cengialtii" 'Mostar', but 'Tid-bit' appears to be darker.  'Mostar' is a bit different from my other two clones of cengialtii, 'Munich Blue' and 'Loppio' in different shape and proportions to the flower, and in having more veining near the base of the falls; also, 'Mostar' is lighter in color than these.  'Loppio' comes from a different area than cengialtii is supposed to be from too.  A sample of three is not much to go on though!

 

As for Sturtevant's introductions, I have suspicions about a few of her introductions' parentage, I don't know that many 'Sturtevant' cultivars, but most of the ones I find suspect are listed as having a clone of I. pallida as one parent and a tetraploid as another.  One would need to count chromosomes to be sure, but these appear to be pure I. pallida and to be diploid based on every detail of plant behavior and morphology.  Among these are 'True Charm' and 'Prince Charming'.  Parentage is not given for 'True Delight', but it appears to likely be from the same parentage.  I suspect that the plicata I. pallida parent self-pollinated, or crossed with another I. pallida in her gardens, and that the pollen intestinally used (or thought to be used) on the flower did not actually produce these seeds.

 

I do not think that mistaken registered parentage diminishes Sturtevant's work, it is just an example of the fact that any cross-pollination made where insects (or even wind) can move pollen around can be diluted from pollen from other flowers.  I don't know Sturtevant's methods, but if she was like most early hybridizers, she probably didn't bag her flowers, and likely didn't even remove the stamens.  Of course I'm just guessing.

 

The only way to be certain of purity is to remove the anthers before they are mature, and to keep the flower totally isolated from any animal life (most especially flying insect pollinators, but even things such as mites and thrips!).  I'm sure that in most cases the intended parentage is correct, but there are exceptions, and it can happen to even the most careful hybridizer (I've gotten some pretty weird hybrids from what was thought to be careful pollination of several types of plants in the past, and I'm quite careful - some desirable, most garbage).

 

There are many registered Iris cultivars that are pure species, yet that were never registered nor recognized as such.  Many we can never be positive about, but we can be pretty sure from things like morphology, behavior, and cytology.  These are most often not field collected plants, but rather seedlings grown in cultivation; or, they are field collected, but field data has been lost.  No matter how many generations they have been in cultivation, if they are of pure species parentage, they are still individuals of that species. 

 

It seems to me that there are more I. pallida and I. lutescens than any other species that were registered without recognition as actually being pure species.  However, I'm sure there are plenty of others that I just am not recognizing. 

 

I. x germanica has a fair number, but is is a hybrid "notho species" as apposed to a true species.  It has a number of clones (cultivars) that are registered under cultivar names and rarely recognized as species.  For example 'Crimson King', 'Nepalensis', 'Susa', 'Vulgaris', 'Florentina', 'Elsie Crouch Diltz', 'Kotchii', etc.  Also, in my mind, 'Albicans' and 'Madonna' are probably I. x germanica, as are likely a number of the older "created" Intermediate Bearded (44 chromosome) cultivars.  However, in the case of the "created" cultivars, they can't be referred to I. x germanica with any confidence until the actual parentage of the "wild" I. x germanica is known.  [Anything with the same parentage, whether occurring naturally or in a garden is still referable to the same "notho"species name.]

 

I can't help being suspicious that a number of MTB's are still pure I. variegata, but almost none are registered as such.  I realize that the majority are not, and for many there are big gaps in the known early pedigrees, so it is impossible to be certain for many (except perhaps some day through genetic analyses). 

 

It is even possible to get a pure species offspring from a mixed ancestry, though the odds of chromosomes pairing up just right for this to happen are usually extremely low; however, as long as the parents carry a full set of chromosomes from the same species in both the mother and the father, it is possible.  Problem is, it would be very difficult to know for sure, without being able to actually identify all the chromosomes, and without being able to know for sure that there were no crossovers or other events that have altered the original chromosomes.

 

Another good example of a cultivar that is clearly a wild species is 'Amas', a wild collected TB tetraploid.  This and similar plants have been given several names, often in the form of a species, occasionally as cultivars.  They probably represent relatively few or perhaps even only one wild biological species.  Some do bear species names such as cypriana, mesopotamica, ricardii, trojana, varbossiana, etc., while others such as 'Amas' are not referred to a species name, even though they are clearly derived from wild populations.

 

There is a philosophical question were we might ask how much change in "captivity" is needed before the domestic creature is considered a new species.  To me, as long as the "captive" plants [or animals] can breed with the wild, they are the same species.  We call wild cats, dogs, horses, cattle, chickens, and many other animals by different species names from their domestic derivatives.  Personally I think this is silly, a dog is still a wolf, even though it looks a bit (or even a lot) different, and chickens breed freely with jungle fowl when they meet (as is rampant in Hawaii), but regardless, these animals have been "domesticated" for many many many (thousands of) generations.  Iris have not.  A few things that cannot be traced with certainty to wild ancestors, or that are so different that they are hardly comparable to their ancestors do exist, such as corn, wheat, etc., but there aren't too many things this totally changed by captive breeding (yet).

 

Sort of got off on a tangent there.  Fuel for all sorts of debate I fear.

 

Dave