According to RHS, 65 registered grexes have Mimi as the pod parent, and 5 as the pollen parent. I don't know the ploidy of this clone, and it appears that some Mimi clones can breed as if tetraploid. When visiting a colleague's greenhouse earlier this week, I was shown another Mimi clone which was half the size of 'Mary Bea', flowers and all, which made me think that his clone may be the diploid form. Regardless, given the intense raspberry jam colors, I can see why many have used this grex for additional breeding.
However, a curious thing happened during flower development. While most inflorescences yielded normal-looking flowers, one spike gave rise to flowers in which the posterior (lower) half of the lateral sepals partially transformed into the lip! Not all flowers on this spike show the transformation, and the degree of transformation varies between flowers.
Note the transformation to callus ridge.
From my previous profession as a research scientist, such homeotic transformations (the transformation of one body part into another body part) immediately indicate to me that the interactions between at least two transcription factors that specify the different flower parts are impaired. However, I studied animals, not plants, so I need to browse the plant literature. I expect the plant developmental biologists already have a working model to explain this phenomenon.
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Obviously a 4n mutation of the original. Tbne ventral peloricism is possibly the result of overcloning. The fact that it is not on all flowers suggests it is unstable.
That is a sepal peloric mutation and many people consider it desirable. In some plants it is stable and will breed pelorics. Do a google on cleo's melody 'freakout' or ison's wild thing. There are also stable petal pelorics like vidar 'harlequin'. They do not breed pelorics.
It would be interesting to self-polinate one of your peloric flowers or cross two of the peloric flowers. Mary bea is supposed to be a diploid that often breeds like a tetraploid.
...i love Cymbidium Mimi 'Mary Bea'...divided my original into six and sold four...my two are currently in bloom...i'm happy to run across another owner...
...p.s., isn't george hatfield a pleasant person to be around?...i attended his lecture at the san francisco orchid society mtg and bought six seedlings...
I like Cym. Mimi 'Mary Bea' for it's ease of flowering and nice color. It would rank higher for me if it had some fragrance, something akin to tracyanum, sinense or mastersii.
I divided the plant once the sprays were beginning to fade, discarding those pseudobulbs that gave rise to the defective flowers. I simply don't have the space to ascertain if the pelorism is heritable, e.g. when selfed. Mimi has been used so much as a parent that while I might be tempted to use it as a parent, I first need to evaluate my Cyms to see what might be a novel cross, and worth my space constraints.
I enjoy George's company, too. I've found him to have a genuine interest in helping Cym growers improve their orchid husbandry skills, and I appreciate his generosity. It was very helpful to see how George grows his plants, thereby giving me some visual imagery to model my own practices.
Hi Kevin,
I just came across your blog with the sepal peloric variation of your Cym. Mimi 'Mary Bea'. I have seen this as well on mine and other people's normally non sepal peloric cymbidiums. I believe this to be more related to weather conditions - we are in the San Francisco Bay Area. But it did happen on a Cym. Crackerjack 'Midnight' and a friends's orange cym. Neither plant has bloomed in subsequent years with sepal peloricism. If you wish to do some hybridization for the genetic trait of sepal peloricisim, I would recomend using Cym. Cleo's Melody 'Freakout' progeny. 1st and 2nd generation progeny have produced several registered hybrids. Although Cym. Ison's Wild Thing is a first generation progeny of CM 'FO', it has not produced viable seed from a few hybridizers, theorizing that IWT may be a 3N, while CMFO is believed to be a 4N. However, there are probably some seedling cyms that bloomed with genetically sepal petals - it would be interesting to see if it has the suscess of passing on that unique gene.
Pelorism is generally recognised as a heritable trait affecting homeotic genes. "Sepal pelorism" seems to occur in about 50% of the progeny when bred against a non-peloric parent. When two peloric clones are bred together there appears to be more severe pelorism. It's avoided in breeding phals and catts as the distortions become "unaesthetic". Pelorism seems to fall into a pattern of "incomplete dominance" and most are bred using one non-peloric parent. I have often wondered if the "instability" noted in some cases is due to chimerism where only some of the cells carry the mutation so only part of the raceme is affected or it varies from year to year depending on which cells give rise to the flowers. Such chimeric tisse may die out if not carried on into the meristem in the next growth cycle.
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