Oxalis Pes caprae, different flower morphology

[MWP admin]

I met this flower at Mosta. It looks like Oxalis pes caprae but flowers are smaller and more pale. Is it a new species / sub species or just a one in a million defect of the plant?

[jackpot]

very interesting

[MWP admin]

nother example met at Mistra

Flowers slightly larger but definitely paler. (compare the yellow of the normal flowaer at the background)

[jackpot]

still interesting- have not yet noticed the variable colours

[MWP admin]

Usually I am over optimitsic as you know me by now, but this time I have the feeling that we are looking at some defect or mal-nutrition or disease, not a new species. I remembered to check the leaves of this plant and it was alike the normal Oxalis pes-caprae.

Still, its prone to investigation. They are very rare to encounter.

[Adriano]

I've noted the different morphology of the oxalis yesterday at Fawwara. Pitty I didn't take any pictures. The petals appear to be 'bleached', i.e. the petal colour is washed out. I didn't think it would be so common.

I wouldn't think it is malnutrition. Other oxalis pes-caprae around the specimen I've seen looked pretty much normal. It was only this oxalis which was different from the rest.

[MWP admin]

Same observations. The malnutrition suggestion as you said does not really hold that well, but I was firing possible biological explanations of what could be seeing. For the same explanations it is unlikely to be a parasite, or intoxification.

The 2 most possible explanation that I arrrive for the moment is either a new variety of oxalis pes-caprae or some recessive gene with that phenotypic characteristic. Not much literature about it.

In the second time that I met the specimen, I noted that the leaves are identical to the normal-flowered specimen.


Thanks for posting your observations (observing is the talent of the scientist) and hope you got the last email from mwp admin about 'green bad deeds'

[MWP admin]

I have found another population of this 'pale variety' of Oxalis pes-caprae. This time these where not found as individual plants but a rather numerous populatio at Dingli, at the wall of a field. They do not seem to suffer any malnutrition. Photo taken in April (still back-loged for difficult IDs!)

The pics explain many details and differences from the normal form. The obvious question is - WHAT IS IT ??? Should it be considered as O. pes-caprae period!

I think this is food for the experts only!

Oxalis pes-caprae profile on the link below:
http://www.maltawildplants.com/OXIL/Oxa ... arpes.html

[Edwin Lanfranco]

Such variants do occasionally arise in Oxalis pes-caprae. It would be interesting to cultivate such variants to see if the same happens the following year. That would establish whether the variant is genetic or due to some stress being suffered by the individual plant[/i]

[MWP admin]

This case, which is over 1 year pending, is finally solved!

Edwin, regards your experiment, I have a good idea where to locate this population and so next Jan, I will give a look and report back here. In the prev specimens (2006), I found a single plant, amongst a big pop of typical Oxalis p.c. so, I would lean towards the genetical reason rather than the environmental one. On the other hand, the latter maybe someone tossed some 'poison' on that patch and affected their phenotype. Who knows??!

Thank once again for you input.

[IL-PINE]

I still think your dog has caused some mutation, mwp

[RB]

I have one q.

If Oxalis reproduces purely vegetatively, are not all the plants in Malta and Gozo genetically identical and technically just parts of the same plant?

If correct, then the specimen/s above may just be having a bad day. But being in the company of other "normal" Opc this seems unlikely. Is it possibly a hybrid with a seeding Oxalis sp.?

Ie the product of a seeding Oxalis which assumed most of the characteristics of Opc, including the vegetative only repro.



RB

[Edwin Lanfranco]

It is not a hybrid since local Opc seem unable to cross-fertilise. However there are such things as somatic mutations which occasionally arise in clonal populations. Then remember that we have two distinct clones of Opc: the normal one and the flore pleno variety. Where they imported separately?

[RB]

I can definitively state that the reason for the smaller, discoloured flowers with varying shades of white (from completely to partly) is stress. Reason being that I inadvertently "created" a fair number of these variants.

I cleaned up several patches of Oxalis using a herbicide, around a month ago, and at the immediate periphery of these patches, many of the plants which only got some "overspray" and did not die, now producing these types of flowers. There are no other of these differently coloured/sized flowers anywhere else but in the immedate proximity of the treated areas.

In nature stress can obviously come from other factors not to mention that human induced stress is often a case, by other means rather than mild herbicide poisoning.

RB

[MWP admin]

[quote="MWP admin"] On the other hand, the latter maybe someone tossed some 'poison' on that patch and affected their phenotype. Who knows??!
quote]

Dear RB,

I fully agree with your conclusions, which were one of my thoughts some time ago, and now I have leaned to be the most plausible reason of this phenomenon. Recently, I experienced a clearing of a small area most probably by application of a broad herbicide (and not-surprisingly for creating a new bird trap site from its rectangular affacted area) and there where several specimen of pale-yellow Oxalis pes-caprae.

If it was an incidental genetical mutation, it would have a random distributed occurence, but as we know, we rarely see such variants in undisturbed populations. So, like RB, I think that chemical stress causes these pale yellow variants.

[Glimbo]

Interesting ... shows how tough the little blighters are! g

[RB]

The effectiveness of glyphosate on Oxalis is very much dependent on timing. If the timing is right, the effectiveness is nothing less than 100%, and permanent. If not, they can seem to simply enjoy the sprinkling. Close to flowering time has worked for me unfortunately I did not keep records of when it did not, but later in the season seems less effective from memory.

RB