28 November 2011

Just went and checked the green seed from drying pods off my Melting Mammoth that I sowed a few days ago - one of the peas has already sprouted! Most pleased - I have just picked the fully developed pods from my first crosses in the first few days of November, so am thinking of sowing some tomorrow or in a couple of days. Have put the pods in the dehydrator this morning - on very low -  to hasten the process, but I'm not sure that I should have...
If I sow tomorrow or the next day, I should have emerging plants before I go away 2nd week of December, then leave them on the watering system in big pots to grow until I get back. Cut a few weeks out of the cycle.

I've spent the weekend musing on strategies now that I've actually got some material to work on.

Of my early crosses I got full pods from the first 5 crosses or so (the later pods are very incompletely filled, so that material will probably have to wait until late summer for sowing - I can't afford to take risks with it). These were hangover crosses - being a bit under the weather, I used recessive pollen on dominant mothers, so I won't be able to tell from the F1 plants whether my crosses were successful or if the seeds are from self pollinations. I also wrote down the names wrong citing Oregon Snap as the pollen donor - except there is no Oregon Snap parent - and a few days later when I re-read the labels, I couldn't remember whether I had used Sugar Snap Bush or Oregon Spring pollen. At least they are both white flowered,multi flowered, powdery resistant, dwarf, edible podded - just that Sugar Snap Bush also carries the n gene for thick pods.

I've got 3 full pods of these mislabelled crosses, so i could potentially have 18 or so seeds. I can probably afford to experiment with half, say 9 seeds.

However, the Lost Seed Co variety of purple podded (PP(LSC)) only developed 4 full pods on each plant. At say 6 peas per pod, that's only 24 F2 seeds per F1 plant - not a lot for a grow out. But I could get ~ 500 seeds at the F3, enough for a substantial grow out of say half, with half put aside to delve into if nothing turns up in the first F3 batch. So this week I might sow half the seed from these first crosses (which were 'wrong way' crosses), 12 weeks to seed harvest (that's what the first generation took) takes me through to the end of February, sow all the F2s to have them flowering at the end of April, with seed for sowing at the start of May. If I get about 12 seeds from each of these summer grown peas (Rebsie suggests seed number and quality is poor from hot weather plants), I could potentially have ~100 F2 seeds for late February sowing.

The F2s will have segregated and various traits will have been expressed, so I might have some stable recessive lines - dwarfism or powdery resistance or uncoloured leaf axils to select from. I'm not going to be able to tell about the low fibre pod characteristics without sacrificing some pods, which I'm not willing to do. Since I'm after purple podded snows, I would put the seed from the uncoloured leaf axil plants to one side, and grow out the rest (depending on number) - purple axil colouration seems to be linked tightly with A the anthocyanin gene which I need for purple pods - at least according to Mendel. Since it is dominant, if the plants were carrying even one copy (heterozygous) it would be expressed, so no purple axil, no A.

I've also crossed Purple Podded (Select Organics) with Yellow Podded, looking for a red pod. For a red podded I need purple pods (A_Pu_Pur_) over yellow pods gpgp. Yellow Podded already carries A, so all the progeny of the crosses will be AA. So to get a red podded in the F2 generation I need Pu_Pur_gpgp, the odds of which are 3/4 X 3/4 X 1/4 = 9/64 or about 1 in 7 - if the genes are independent.

So I might also sow some of the PP(SO)XGP F1s this week - since the outcome is not really a huge target for my program, the seed is a bit expendable, and it might be encouraging to see how it segregates next autumn. And I might just turn up something interesting...

Ditto with my Yellow Snow crosses, trying to turn up a half decent yellow snow pea. I've crossed Golden Podded with Oregon Spring and Delta Louisa, both dwarf double flowered snows. I should have a few seeds to spare, so I might try a few out.
(I'll come back and put some pics in this post a bit later)

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