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In the F3 Golden Sweet x Bijou (GsxB) grow-out, I'm getting mostly small pods, which tells me the allele for large pods is recessive. Several plants have produced some beautiful, large, lemon-yellow pods and I'll certainly be saving their seeds. This is exactly what I wanted from this cross.

BSxB02

It's not all roses though; the hybrids don't seem to have inherited the fresh, lemony flavour of GS pods (edit: one of them, YBO03/03, has lemon in its flavour profile - yayness and W00t!). Hopefully that's something I can rectify by backcrossing the next generation with GS, re-introducing GS flavour genes. I'm not too worried at this stage though; the pods I've tasted had a pleasant mangetout flavour. I don't want to eat too many pods; I'd rather the candidate plants produced lots of F4 seeds!

Earlier in May I noticed two plants had produced, on a single node, one normal-coloured flower and one with lighter-coloured standard petals (the ones at the back). Alas the flowers later darkened to their usual pinky-purple, so this must have been environmental rather than genetic. Ah well..

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GSx Bflowers1


My new experiment, a cross between Golden Sweet and Shiraz, has worked. I mentioned in my last post I thought I'd mixed up the GsxS F1 seeds with some GS; I'm now certain I did. The golden pod (gp) allele that stops plants making chlorophyl in the pods is recessive and can't express itself unless its dominant counterpart is absent. Since the F1s received one allele from each parent, and since one of those parents has green pods, the F1s have one functional copy of the dominant GP allele.

But Shiraz is a purple-podded variety, which in peas requires the production of anthocyanin in the pods. Golden Sweet has the dominant, 'master switch' allele A that switches on antho production but neither of the alleles that cause antho producion in the pods. Cross them and the result is this:

GSxB01


In peas, both green pods and purple pods are dominant traits, causing some interesting colour effects. My plants are producing some almost fully purple pods, and some with a piebald streaking of purple over green. I'm hoping the next generation will produce at least one fully purple-podded plant.

BsxB02 0


Shiraz is a semi-dwarf variety, reaching 3-4 feet, whereas GS easily reaches 5-6 feet, which the hybrids have done. Tallness in peas is a dominant trait, thus my F1 plants are all tall and I know my cross worked (yay!). I also know I'll be roguing out unwanted dwarf types from the F2 generation. Shiraz has another weakness; it's sold as a mangetout and although the young pods are edible, they soon become tough and leathery with none of the finesse of Golden Sweet, a true mangetout. I really think the breeders could have done a better job and I know I'll be roguing out shelling peas if the F2 generation. But it'll be worth if if I can get those purple-pod genes into Golden Sweet!
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