Hi, Robert, thanks for very detailed report! It is really very interesting. I have similar observation in transgenic plants with altered hormonal balance. I can expect that some of the plants with abnormal flowers may be transformed by one of the soil bacteria and may have altered hormonal balance. Did this plants growth faster or have a bigger size to compere with the others? Thanks again for the interesting message!

Thank You, Vijay, for your answer and the interesting link to a really interesting article. >30 years ago, I learned that plants have multipotent stem cells (meristem) basically everywhere, which higher vertebrates should not have. Nowadays this view appears to change, with embryonic stem cells in mice 20 years ago, many human tissue stem cells - and a few years after I was searching for something like the metastasis originating cell, my former lab at Stanford brougth the idea of a cancer stem cell into the field, probably most pathologists may find very interesting.

So, my photo of that flower shows some kind of dysregulation of the usual morphology of that species - I agree this is a very wide step from cancer stem cell research to plant evolution...

Hi, Robert, thanks for the interesting observation! This is not surprisingly for me because all meristematic cell can undergo temporary de-differentiation under certain conditions. But thereafter were able to recover back with formation of new organs. How often have you observed such phenotype?

Hi, Robert; "dysregulation of the usual morphology": the molecular biology of floral development is being unraveled thanks to many mutants like yours. There are plenty of literature on this regard. Changes in floral meristem of palms make them produce new shoots instead of flowers is another example (I saw)...

Thanks, Taras, Luis and Vijay for your answers.

I originally observed this phenotype in one single plant out of hundreds in my parents garden a few years ago - never shave seen this in this species, but other asteroid "garden flowers" seem to have that phenomenon naturally. I recovered the seeds and could grow about 8 plants with only 5 flowering the next season - with the same phenotype (more or less, differing in the low number and medium lenght of the secondary flowers). Over the years I selected the most striking examples; meanwhile, they have many more secondary heads as originally, but now extending longer. I now grow some plants over the second winter (!!!) in a tomato house - well, not heated, so I lost most of them during two winters... but one primary flower will open this week (with snow almost everywhere in Germany). I didn't know this species can hibernate.

What estonishes me mostly: The phenomenon comes in ALL descendants, meanwhile I could find flowers in yellow, as well as in orange color - with or without brown or yellow/orange in the middle of the flower - all combinations, but always with this striking phenomenon - meanwhile sure seen thousands of my "medusa-like" flower heads.

Hi, Robert, thanks for very detailed report! It is really very interesting. I have similar observation in transgenic plants with altered hormonal balance. I can expect that some of the plants with abnormal flowers may be transformed by one of the soil bacteria and may have altered hormonal balance. Did this plants growth faster or have a bigger size to compere with the others? Thanks again for the interesting message!

Thanks, Taras, for your question. The original plant appeared to be much smaller as the usual, but the first daughter generation appeared to be normal. Later generations appeared to be quite normal, sometimes I had the subjective impression they grew faster, bigger, but since I did not want to "dilute" those genes, I did NOT grow any other (normal) plants around. I tried to rule out bigger effects from soil or light. Well, with N,P,K salts the plants grow slightly better, but the phenomenon appears to be independent of how much sun or salts the plants receive (this is not a real scientific experiment, I don't have the grounds for that - so, I am happy with the results).

Surprisingly, only the outer row of seeds in a primary flower head appears to "transform" into secondary flowers (with green foil, i.e. like a complete plant), but so far, no tertiary heads appeared... but it was so surprising for me that the secondary flower heads produced fully fertile seeds.

Last year I observed the first half seed, half flower heads within the secondary heads... so, it is reasonable to assume they are monoclonal without recombination...

Thanks, Robert, the observation you made is really interesting and very important! I am almost sure that there are alteration in hormonal balance in these plants, which became pretty visible on the flowers stage. It is very logical because reproductive stage is much more sensitive to any hormonal dis-balance, to compare with quite large leaf or stem. I think that the reason of the phenotype is a horizontal gene transfer between one of the soil bacteria (Agrobacteruim, for example) and plants. Once bacterial gene were integrated in genome, they will come the the next generation. I am attachnig the picture of the flowers form plants with altered hormonal production. Under certain conditions one can see such flowers.

In tissue culture treatments, it is possible to see these types of abnormalities. I have also so many pictures from different species produced in vitro. I also agree Prof. Pasternak, since generative organs are higly subjected to the phthohormonal imbalancing as seen. This picture claims how evolution acts on plants as Vijay's comment. Not only totipotency but also plasticity of the such organs such as flowers emerged from one-head might provide a new insight for diversity as a new adaptive characters. Even it seems little bit bizarre to our eyes :)

Thanks, Taras, I see the mixed organs of the flowers in your foto - I remember that I've observed similar mixing of organs in at least one tulip (over several years) in my parents garden (i.e. at the same location where I also found the very first original plant of the "medusa-like phenotype" in the other plant species, so that could be related to similar infection of the two plants and hormonal dysregulation. I only found last year the (in my view) corresponding irregular mix of half seeds and half secondary flower heads (or any different ratio of both), but couldn't find those rare fotos yet, but with different qualtities of deranged rudimentary flower heads - but in all earlier years that never happened.

But in my original examples and most of those cases the flower heads are very regular, I am still thinking of some clonable mutation within some segmentation responsible gene or something. But I should exclude some bacterial (or also viral), or non-flower DNA. (Just in case I once may get the time and ressources of starting something with that). On the other hand, if bacterial infection can change the hormone state within plants, it is reasonable to conclude that human cancer could have (many) similar origins due to bacterial infections... (not only the human papilloma virus somehow related to cervix cancer, or also the bacteria Helicobacter pylori related to stomach cancers, but many more.... But I was more hoping to get some new clues for stem cell research...

Attached just another, but smaller, typical example from earlier last year.

And here is one example of the NEW generation: 5 "secondary" flower heads grew out of the border of their primary flower head (which already produces new seeds) - same phenotype, i.e. this new generation is now very stable ! This example is the only one I grew with almost no direct sunlight (north window); usually I allow the plants to grow on a south balcony with direct sunlight all day long. Now I can basically exclude this is an effect of light exposure. The other surprise to me, the mother plant of this example is now over three years old (same phenotype but bigger plant now) - I couldn't beleive that Calendula officinalis (German: Ringelblume) can survive several years (it usually does not, and does not need to, since the seeds grow easily from year to year - but this is not related to this phenotype).

I still beleive it would be interesting to look which genes are involved in this phenotype.

I notes since 2004 mutation of the yarrow plant,achillea millefolium,schafgabe?,up here Yukon & Alaska.< I-cing >

BIG SURPRISE: germline mutation "deleted"? (see no. 3)

Well, after finding the first slight "mutation" and randomly selecting over years for the "most mutated" phenotypes, I should point out:

1) The original "secondary flowerheads" did not produce any seeds; later generations produced somehow empty seeds; only recently such secondary flowerheads produced fully fertile seeds about 2-12 per secondary flowerhead; I assumed these fertile seeds very likely should be of clonal origin with their mother plant (BUT this is only an assumption! I have no genetic proof or so, just the single flowers appear to produce immediately seeds...

2) Only very recently, I found a few plants with even "TERTIARY flower heads" - i.e. from some of the secondary heads another round of heads developed, usually only very few, like 2-4 per secondary head. (I assume again those should be clonal!!!)

3) THIS spring I managed to grow two plants of the seeds of such a tertiary flower head: the first plant grows at normal speed and looks TOTALLY NORMAL, i.e. absoluteley NO SECONDARY flower heads!!! The second plant is growing slowlier and is still too small for flowering.

QUESTION:

Is my assumption wrong?

Or - more interesting - if my assumption is right and the seeds from tertiary flower heads are clonal, then how could it happen, that the postulated germline mutation got lost and the plant looks totally normal - after several years of selection for the phenotype of secondary flowers. Is there a "repair mechanism" in plants which can delete unnormal mutations?

I always think of the phenomenon of "atavism", when for example Digitalis plants develop on top of the plant (rarely) a fully (ralidally) symmetric flower, called Peloria (in contrast to all other flowers there) - which is interpreted as an ancestral program in their evolution and derivation from such plants with those radially symmetric flowers...