Last year when I was podding some Golden Sweet for seed, I noticed some with solid purple seeds. I saved the seeds and have grown some of them on this year.
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Purple Golden Sweet and regular Golden Sweet
From what I have found on the net it is a mutation/variation which may be due to environmental factors. Unfortunately it is unlikely to produce more purple seeded pea seeds, but I couldn't resist trying.
Beans as well as peas can do a similar thing, has anyone successfully grown out and reproduced any of these variations?
I have always taken it for granted that some pea varieties have different colour seeds and not really thought about it. Thank you Jayb for showing this interesting mutation. Where it happens seems to be with purple flowered varieties. But on the other hand there are purple flowered varieties that don't have variable seeds. Golden Sweet here have exactly the same variation in seed.
Yes I have seen this that with beans as well. What usually happens is an inverted seed pattern. This happens with the 'Pinto' type of beans quite often. The term 'pinto' is used very loosely here.
Here is a url that shows this phenomenon:
http://farm4.static.flickr.com/3006/3364309090_23c8b3928e_o.jpg
This is basically a white bean with a red swirl and spot pattern. This picture shows nicely that some beans are red with white pattern. It gets more complicated because the invesion is not complete. The swirls (tiger stripes) in the pattern stay the same colour and do not get inverted, but the spots and the background colour do.
Anyway, if one of the odd coloured beans is grown, the resulting beans are the usual colouring again (with very few inverted ones). Did you mean this Jayb?
Another bean that produces different colour seeds is Ukrainian Comrades. Here is a picture:
http://www.heritageharvestseed.com/pages/bean_thi.html
Third one down
These are not crossed, the are genetically pure, yet have different colours. Fascinating subject!
Facinating JayB and galina ;D
Reminds me of Rebsie's Blog http://daughterofthesoil.blogspot.com/
I'm sure there is a part where she discusses some peas she has been sent and their colours.
I will be facinated to here how the experimental grow turns out. :)
Okay heres a little bit of genetics to help
most traits such as being purple have two bits of code on the dna (one from each parent)
xx say.
now traits are either dominant that means that it occurs if either parent has the right code
for instance if little p is green and big P is purple
any pea that has either Pp, pP or PP will be purple and only those that are pp are green
or they are recessive which means they only occur if both codes are the P
So peas could be any of these PP Pp pP or pp
So if purple is dominant and your pea parents were both Pps
then you might get a mixed bag of offspring where
3/4 would be purple and 1/4 would be green.
So maybe you can see that if a trait is dominant then the parents dont have to be "genetically pure" to be purple and can produce green offspring and only in rarer case where a trait is recessive and therefore both parents only have the PP would all offspring be truely pruple and only give rise to purple offsping themselves.
Its a back of a f*g packet explanation but mendel the father of genetics actually did his experiments on the pea familiy.
I know to many pps
:)
x sunloving
There has to be a gene that codes for anthocyanin expression in the seed, as some varieties do have reddish seeds. The coloured seeds in Goldensweet turn up in a far smaller proportion than the 25% we'd expect if your idea is correct, so something else has to be at work as well.
It's likely, incidentally, that goldensweet is one of Mendel's varieties. There aren't any other old, yellow-podded mangetouts he could have used.
Interesting post Galina, those beans are stunning. Yes that is what I was meaning, because as much as I would love purple peas, I don't think it is going to happen from my mutants. I suppose I'm just interested to understand how/why peas and beans can throw colour mutations and then no greater occurrence in future generations of their progeny. I think there may be a common gene in the purple flowered varieties as I had 5 solid purple Purple Podded too.
I'm no expert in understanding genetics but I agree with Robert that there is more happening than pure genetics. However I would be happy if that is the case, there should be some evidence of this in the grow outs I'm doing. Depending on what harvests and the space available, I may try and grow a late crop from the offspring.
Although having just written the above I'm thinking of that awfully long list I remember reading about codes and recessive traits in tomatoes. So much to learn, I feel I have not got out of preschool yet!
Is it possible for several recessive genes to be at work to produce/allow purple seed? If this is the case can the rate of purple seeds from these seeds as opposed to an average mix of Golden Sweet be calculated?
I'm looking forward to finding out too ;D Mortality, I'll post later in the year.
Anthocyanin seems to be fairly straightforward, but there are all sorts of environmental effects which influence the expression of genes. Most goldensweet seeds evidently have the anthocyanin switched off, but sometimes something switches it on.
Quote from: Robert_Brenchley on April 27, 2010, 10:07:04
There has to be a gene that codes for anthocyanin expression in the seed, as some varieties do have reddish seeds. The coloured seeds in Goldensweet turn up in a far smaller proportion than the 25% we'd expect if your idea is correct, so something else has to be at work as well.
It's likely, incidentally, that goldensweet is one of Mendel's varieties. There aren't any other old, yellow-podded mangetouts he could have used.
I don't know about purple seed, but in the case of pods there are three dominant genes involved. You need the dominant form at all three loci in order to see purple pods. I think the way it works is one gene stimulates anthrocyanin production in the stalks, one the flowers the third the pod, if any are the recessive form then the anthrocyanin chain is broken and you get non-purple pods.
Perhaps there is something similar in play with purple seed, maybe a few recessive genes combined witha dominant, or some such.
I'm not convinced by the environmental line.