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The chicken or the egg?


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Hi all.

Many years ago I obtained an S. purpurea ssp purpurea from Mike King (pp6) only to discover the flower had been open pollinated so I subsiquently germinated and grew on the seed that produced 25% anthocyanin free plants.

What I discovered was after some questions and a bit of homework was that the parent plant (MK-pp6) was heterozygous.

For those of you that are unfamiliar with this term it is explained in the following link.

http://anthro.paloma...el/mendel_1.htm

The thing that has sprung to mind is that if the heterozygous plant is derived from a hybrid of two forms with one being anthocyanin free and the other being a dominant parent. Where did the anthocyanin free parent come from?

And why are these forms not popping up more often in nature?

Let me know what you guys think.

Cheers.

Ian.

Edited by Ian Salter
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Hi Ian, its a long time since i did biology at school,but aren't some plants in Ireland the veinless form.

Could one of these be the gene carrier?

As for why they don't occur more in nature,

I think they do,but don't survive. I think they get out competed by other normal seedlings.

I grow a few antho free plants,and some from seed.I find some of them are very slow from seed,especially whilst small.

some don't even seem to want to survive,the seed looks good,they germinate o.k and the cotyledon leaves open or try to,then they just seem to run out of energy and die.

Not all are like this,some plants now are producing good seed,that germinates and grow well although still slowly whilst small.

All this is down to a few growers who are spending their time and effort into a long term project.

ada

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A lot has been learned since Gregor Mendel published his findings on simple genetics in Sweet Peas, but there are a lot more complicated things that are involved such as modifier genes, sex related/influenced genes, and of course, the plasmid organelles such as mitochondria, chloroplasts, and centrioles, all have their own unique prokaryotic DNA and are inherited by the (female) egg. We are still learning how they influence the nuclear DNA.

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but aren't some plants in Ireland the veinless form.

Could one of these be the gene carrier?

The site near me is predominantly veinless. For the last 2 years I have looked for a yellow flower among the sea of red, but never seen it...I have selfed some flowers and hopefully something might come from it.

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  • 2 weeks later...

Hi all.

Many years ago I obtained an S. purpurea ssp purpurea from Mike King (pp6) only to discover the flower had been open pollinated so I subsiquently germinated and grew on the seed that produced 25% anthocyanin free plants.

What I discovered was after some questions and a bit of homework was that the parent plant (MK-pp6) was heterozygous.

For those of you that are unfamiliar with this term it is explained in the following link.

http://anthro.paloma...el/mendel_1.htm

The thing that has sprung to mind is that if the heterozygous plant is derived from a hybrid of two forms with one being anthocyanin free and the other being a dominant parent. Where did the anthocyanin free parent come from?

And why are these forms not popping up more often in nature?

Let me know what you guys think.

Cheers.

Ian.

Hi Ian,

From what I saw when I went round some of the bogs in Ontario I suspect that the Green anthocyanin form of S. purpurea (i.e. S. purpurea ssp purpurea f. heterophylla is quite common in nature. Some bogs I visited had a few of the f. heterophylla plants, some many and some none at all. I found one f. heterophylla plant in one bog where none had been found before. All this leads me to believe that the form occurs quite often in populations independantly and spontaneously. That is, the forms in the various populations are unrelated genetically. Also the original description of the form made by Eaton was from a site in New York State. Presumably the site no longer exists (the form was described some 200 years ago) and is certainly no where near the sites where I found the plants.

There may well be evolutionary advantages for the f. heterophylla plants. Generally yellow/green flowers are better reflectors of UV light and especially in low light conditions of winter appear much brighter, particularly to insects viewing in the UV spectrum. The advantage to a plant that attracts insects are obvious, particuarly in the more northerly regions where S. purp ssp purp grows. This is all theory of course though I can say that the f. heterophylla are pretty easy to spot in an open sphagnum bog. The plants are almost fluorescent! It would be fairly easy to carry out counts of trapped insects in red and f. heterohylla plants of course.

This is an area that has long interested me. The genetics are unlikely to be simple (they rarely are). In some Sarracenia species for instance there appears to be a link between anthocyanin plants and lack of vigour. The Green S. minor (now S. minor var. viridescens) is one example of this and is almost certainly an indication of different genetics than with certain other Sarracenia species. Again this might be completely circumstantial but it does seem that species that normally produce red flowers do not have a problem with lack of vigour when a chance anthocyanin free form occurs, whereas species that produce yellow flowers mostly do - possibly with the exception of S. alata? It does seen possible to breed out the lack of vigour - the antho form of S. minor was crossed with S. minor var. okeenfenkiensis for instance and most of the offspring are perfectly vigorous. What that says about the genetics is way beyond the limits of my knowledge!!

Phil

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Interesting stuff.

Just had a nosey about anthocyanin production here.. http://en.wikipedia....iki/Anthocyanin

where I also found thefollowing text that is a basic condensed version.

"Any even minor disruption in any of the mechanism of these enzymes by either genetic or environmental factors would halt anthocyanin production. While the biological burden of producing anthocyanins is relatively high, plants benefit significantly from environmental adaptation, disease tolerance, and pest tolerance provided by anthocyanins."

I read further to see they have produced 'blue' tomatoes and the benefits of anthocyanins in the fight against cancer that seem hopeful (although far more effective if your a rat).

Either way it is a good read and might point in other directions for reasons for the apparent weakness in anthocyanin free plants and the fabled blue Sarracenia Mike was telling me about.

Cheers.

Ian.

Edited by Ian Salter
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Further reading here... http://www.charlies-web.com/specialtopics/anthocyanin.html

Very interesting that the anthocyanin free forms grown in cultivation may just need sun screen lol, as It reads that anthocyanins offers protection from UV that can damage DNA and halt cell division and protein production.

This might be one reason for the apparent slow growth in these forms or the disruption in the anthocyanin production may mean other elements? are not produced.

Ian.

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Further reading here... http://www.charlies-web.com/specialtopics/anthocyanin.html

Very interesting that the anthocyanin free forms grown in cultivation may just need sun screen lol, as It reads that anthocyanins offers protection from UV that can damage DNA and halt cell division and protein production.

This might be one reason for the apparent slow growth in these forms or the disruption in the anthocyanin production may mean other elements? are not produced.

Ian.

Interesting stuff!

There is certainly something in the idea of red colouration being produced as a sort of sunscreen. Certainly some HV and all red S. flava forms need plenty of sunlight to produce their best colouration. There is a site in the Florida panhandle with many extremely dark forms of S. flava yet seeds collected from this site and grown in cultivation in the UK rarely if ever produce anything like the same degree of redness. The inevitable conclusion is that the plants are reacting in some degree to the high levels of sunlight in their natural habitat. As usual the case is not clear. S. flava var. rugellii produces no red colour in its pitchers no matter how much sun you give them and indeed there is an argument that redder pitchers could be less efficient at digesting insects. A yellow pitcher will reflect more sunlight so in theory the contents could stay slightly cooler and may be less susceptible to bacterial and fungal infections. There's a PhD for someone there!

I'm not sure that it follows that plants that produce no red colour are weak growers because of damage to their cells from high UV levels. If that were the case then they should grow much better in northern Europe I guess. What might be the case though is that plants growing in more northerly lattitudes benefit from having no red in their pitchers because they are able to make the maximum use of every photon of sunlight.

Phil

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I'm not sure that it follows that plants that produce no red colour are weak growers because of damage to their cells from high UV levels. If that were the case then they should grow much better in northern Europe I guess. What might be the case though is that plants growing in more northerly lattitudes benefit from having no red in their pitchers because they are able to make the maximum use of every photon of sunlight.

Phil

Correct Phil, which is why only S. purpurea has naturally occurring populations of all-green plants in the form of heterophylla.

For all the rest of the species, it's just one more negative attribute due to their location. And is naturally selected against being maintained or promoted in these southern populations.

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Dear Ian,

Could explain your seedlings in more detail? Are they hybrids? Or just S. purpurea purpurea?

I'm thinking the easiest place for a heterozygous (for all-green) plant to find a heterozygous partner is with itself... Which would give you 25% all-green plants (homozygous for all-green), 75% regular looking plants of which 25% would be homozygous for regular color and the other 50% would be heterozygous. Rich's statements have to due with more complicated genetic operations and don't really apply in this scenario.

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Correct Phil, which is why only S. purpurea has naturally occurring populations of all-green plants in the form of heterophylla.

For all the rest of the species, it's just one more negative attribute due to their location. And is naturally selected against being maintained or promoted in these southern populations.

Hi Dave,

I did hear a long time back that some populations of S. rubra ssp jonesii contained a proportion of antho free plants but I've never had that confirmed. Any thoughts?

I'd agree with your comment about antho free plants being naturally selected out in the more southern locations were it not for plants like S. flava var. rugellii which are predominantly green apart from the throat of the pitcher of course. I wonder if these plants still have red pigmentation even in the green parts of the plant which is not strong enough to be visible but acts as a sunscreen.

Phil

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Dear Ian,

Could explain your seedlings in more detail? Are they hybrids? Or just S. purpurea purpurea?

I'm thinking the easiest place for a heterozygous (for all-green) plant to find a heterozygous partner is with itself... Which would give you 25% all-green plants (homozygous for all-green), 75% regular looking plants of which 25% would be homozygous for regular color and the other 50% would be heterozygous. Rich's statements have to due with more complicated genetic operations and don't really apply in this scenario.

I possibly was not clear enough in my first post.

The parent was S. pupurea ssp purpurea (MK-PP6) a vigorous clone.

Although it was open pollinated it is clear it has just selfed and not crossed and all the seedlings are indeed S.purpurea ssp purpurea in the ratio's you mentioned above.

What I am really trying to work out is if the anthocyanin form developed independantly and became intergrated into normal strains as an inter species cross.

From what I understand, if we cross a typical (homozygous) with an anthocyanin (homozygous) I assume it would produce heterozygous offspring.

One could also assume that where there are populations containing anthocyanin free forms there will also be typical looking homozygous and heterozygous plants.

Now my mind has taken another turn assuming what I said above is correct.. What happens if one crosses an anthocyanin free S. purpurea (homozygous) with S. purpurea (heterozygous) ???

I will dig deeper and get a better understanding of genetics me thinks.

Thanks for the input guys.

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Hi Dave,

I did hear a long time back that some populations of S. rubra ssp jonesii contained a proportion of antho free plants but I've never had that confirmed. Any thoughts?

I'd agree with your comment about antho free plants being naturally selected out in the more southern locations were it not for plants like S. flava var. rugellii which are predominantly green apart from the throat of the pitcher of course. I wonder if these plants still have red pigmentation even in the green parts of the plant which is not strong enough to be visible but acts as a sunscreen.

Phil

We at least assume the anthocyanin production either is not there or has gone faulty in the heterozygous form, other compounds are produced durin the process of producing anthocyanins (that also are reported to have antioxidant properties) so it could be a lack of something else.

Maybe they are just genetically weak also.

It would be interesting to know where all the other anthocyanin forms of Sarracenia have turned up and Darlingtonia for that matter.

Cheers all.

Edited by Ian Salter
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Another thought.

If anthocyanin free forms have been discovered in cultivation then they are either mutations or from a selfed heterozygous parent.

This means there may be heterozygous plants in peoples collections and the owner is unaware lol.

I should go to work i,m late.

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Another thought.

If anthocyanin free forms have been discovered in cultivation then they are either mutations or from a selfed heterozygous parent.

This means there may be heterozygous plants in peoples collections and the owner is unaware lol.

I should go to work i,m late.

To date, all the all-green plants in cultivation have been collected directly from the wild as plants or as seed. Or they were made by breeding regular colored plants with those wild collected all-green plants.

There could be heterozygous plants in many collections, but you'll never know until you self 'em or cross it to another heterozygous plant and grow out the seeds.

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Hi Dave,

I did hear a long time back that some populations of S. rubra ssp jonesii contained a proportion of antho free plants but I've never had that confirmed. Any thoughts?

I'd agree with your comment about antho free plants being naturally selected out in the more southern locations were it not for plants like S. flava var. rugellii which are predominantly green apart from the throat of the pitcher of course. I wonder if these plants still have red pigmentation even in the green parts of the plant which is not strong enough to be visible but acts as a sunscreen.

Phil

They do and the buds tend to be pink, but loose the coloration as they expand.

Any population which sports an all-green individual almost certainly has several more normal looking individuals with heterozygous genomes for being all-green. I think these plants were poached. :(

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To date, all the all-green plants in cultivation have been collected directly from the wild as plants or as seed. Or they were made by breeding regular colored plants with those wild collected all-green plants.

There could be heterozygous plants in many collections, but you'll never know until you self 'em or cross it to another heterozygous plant and grow out the seeds.

I have always been a firm believer that you should self pollinate a variety or form at least once in its lifetime just to find out what the potential is.

There are many growers who argue that selfing plants will lead to weak offspring but it's always an avenue that should be explored if not only to see the latent abilities.

Part of me is wondering if the anthocyanin free forms are an older part of evolution that was less successful but still persistant in the gene pool of the more prevalent anthocyanin producing forms.

Who knows, I don't have the answers and that's why I'm posting here.

Anyone else who can give this thread some input will be very welcome no matter how small (the input that is).

Regards.

Ian.

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I possibly was not clear enough in my first post.

The parent was S. pupurea ssp purpurea (MK-PP6) a vigorous clone.

Although it was open pollinated it is clear it has just selfed and not crossed and all the seedlings are indeed S.purpurea ssp purpurea in the ratio's you mentioned above.

What I am really trying to work out is if the anthocyanin form developed independantly and became intergrated into normal strains as an inter species cross.

From what I understand, if we cross a typical (homozygous) with an anthocyanin (homozygous) I assume it would produce heterozygous offspring.

One could also assume that where there are populations containing anthocyanin free forms there will also be typical looking homozygous and heterozygous plants.

Now my mind has taken another turn assuming what I said above is correct.. What happens if one crosses an anthocyanin free S. purpurea (homozygous) with S. purpurea (heterozygous) ???

I will dig deeper and get a better understanding of genetics me thinks.

Thanks for the input guys.

Ian,

Yes if you cross a Red plant with a Green one then the resulting offspring will appear to be red but 25% of the plants will be heterzygous for the anthocyanin free form. This is because the faulty gene responsible for the lack of red pigmentation is recessive. Genes form new pairs at fertilisation and if one of the genes in the pair is faulty and is paired with a functional gene then that functional gene will override (i.e. correct) the faulty one. I'm trying to use my terms very carefully here!

It is only when two recessive genes are paired together that the genetic fault becomes apparent. If you pair up a plant with one faulty gene (heterzygous for antho free) with a plant that has both genes working correctly then the product will be heterozygous for antho free but all the plants will appear to be normal. If these plants are grown to maturity and then crossed with each other then the resulting plants will be produce (I think!) in the following proportions. 25% normal red plants, 25% anthocyanin free plants and 50% heterozygous for the antho free fault.

There is probably a lab test to detect heterzygous plants but there is no way from simple observation of the plants to tell these apart from normal plants. And again, as far as I know, there is no way to tell if your plant became sponteneously heterzygous or if it was an inhertited condition.

It is a reasonable assumption that there are populations containing heterzygous plants though it should be easy enough to confirm this by examination of seedlings on the site since a proportion will be antho-free even if they don't survive very long.

Now my mind has taken another turn assuming what I said above is correct.. What happens if one crosses an anthocyanin free S. purpurea (homozygous) with S. purpurea (heterozygous) ???

You will get 100% heterozygous plants. You can work out these genetic crosses using a simple table. I'll show you sometime!

Phil

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As it yet been proven that simple mendelian genetics applies to this situation? Im not doubting it just questioning if any research has been carried out. In reality its not quite as simple as one gene determining one characteristics. The characteristic is usually controlled by a number of genes.

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Ian, i think people believe selfing is bad for plants because they relate it to livestock and or people.

It is true,it can produce weak offspring,but this is due to concentrating the genes if you like(for a better term)But this can also lead to better plants for the same reason.

This could result in larger/better coloured plants or even antho free plants,if the gene mix is right.

Line breeding or back crossing is similar,you are keeping the gene pool smaller in the hope of magnifying the good characteristics being passed on to the next generation.

Phil, remember sending me some (F1)? P.V.B Luteola seedlings. These crossed together would produce antho free offspring,you said.

With in days of getting them,two turned out to be antho free.

Can you remember which was the seed parent? Could they have been selfed seeds from the original antho free p.v.b.l?

Or could the red parent be a gene carrier for the antho free trait?

search your memory for me,

ada

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As it yet been proven that simple mendelian genetics applies to this situation? Im not doubting it just questioning if any research has been carried out. In reality its not quite as simple as one gene determining one characteristics. The characteristic is usually controlled by a number of genes.

Phil Sheridan has carried out quite a bit of research on the matter and it does seem to be a case of simple Medelian genetics. For instance some years ago he bred the antho free S. minor with a regular S. minor var okeefenokiensis plant, then crossed the offspring and sold the seed. I bought a packet and they came up 1:4 antho plants to reds which is exactly as expected. I've made a few crosses myself too and the same thing occurs. That's not to say that it's always going to be the same of course but as far as I'm aware none have occured to date.

Here's a link to a paper co-authored by Phil with more details.

http://hortsci.ashspublications.org/content/33/6/1042.full.pdf+html

Phil

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Ian, i think people believe selfing is bad for plants because they relate it to livestock and or people.

It is true,it can produce weak offspring,but this is due to concentrating the genes if you like(for a better term)But this can also lead to better plants for the same reason.

This could result in larger/better coloured plants or even antho free plants,if the gene mix is right.

Line breeding or back crossing is similar,you are keeping the gene pool smaller in the hope of magnifying the good characteristics being passed on to the next generation.

Phil, remember sending me some (F1)? P.V.B Luteola seedlings. These crossed together would produce antho free offspring,you said.

With in days of getting them,two turned out to be antho free.

Can you remember which was the seed parent? Could they have been selfed seeds from the original antho free p.v.b.l?

Or could the red parent be a gene carrier for the antho free trait?

search your memory for me,

ada

Adrian,

I'm slightly confused - isn't the PVB luteola antho free anyway? I'm pretty sure the seedlings I sent you originated from Christien Klein though not directly from him so they wouldn't actually be luteoa anyway since this is a cultivar. I may be wrong of course! Christien had a chance appearance of antho free seedlings in his greenhouse. I'm pretty sure the seed was from his own plants though I can't be certain of this. Also I've no idea whether the plants in question had produced normal seed before or if they are/were in fact heterozygous for antho free.

Jumping to one of Dave's posts - this is one of a number of reported spontaneous occurances of antho free Sarracenia that has occured in cultivation here in Europe. There is one other grower in the UK who found an antho free S. flava though as I understand it, it came in with a batch of other plants from an unnamed/unknown grower.

Phil

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