12 March 2012

Summer seed production

I've just harvested the five F1 growouts I tried as an experiment to see if I could sneek an additional generation into the growing year, and shorten my generation turnover time.
A bunch of seed didn't germinate - I think due to soil borne disease or rot. Lucky they were my excess 'wrong way' crosses.
Of the five plants that I grew in pots, I got 26 seed for one of the crosses from 3 plants, and 19 seed from two plants for the other cross. Not  a huge haul, but useful. Powdery mildew  struck the plants over the last few weeks, and the last of the pods on the plants were fertilised, but failed to develop. I was too busy to spray with potassium bicarbonate.

These F2 seeds will get sown in the next few days, with a potential F3 crop in 3 months. The odds that my purple snowpea is going to show in the F2 is a bit low.
From my PurplePod X PurpleFloweredMammoth cross, both carry A, that turns on purple, so that's covered. But I'm also looking for purple in the pods, that needs  Pu_Pur_ (doesn't matter at this stage if they are heterozygous), and ppvv the two recessive genes for non-fiberous pods (so they need to be homozygous) so the probability is 3/4 X 3/4 X 1/4 X 1/4 = 9/256, say around 1 in 30 for any given plant, and I've got 26 seeds. Twice that number of seeds would have been useful, but the chances aren't too bad.

My PurplePodded X MeltingMammoth has less seeds and is also less likely since MM doesn't carry A. So the odds for a purple snow from any one of the F2 seeds is 9/1024, or around 1/100. With only 19 seeds my chances aren't too good in this generation.

None of these parents were powdery mildew resistant, so I will either have to cross in a subsequent generation, or hope that one of my other crosses (which I'm only growing the F1s of this autumn) carries the genes for that trait.

With a bit of luck, some of the PP X PFM F2s will also inherit the double flower gene from the PFM parent.

On a side note, the Purple Flowered Mammoth was a mis labelled plant that came up in a Melting Mammoth batch - I might have interplanted it with some seed I got from a 'net buddy (Jayendra) to fill in some gaps in the patch, but I didn't keep good records that day, so it will remain as Purple Flowered Mammoth (but I suspect it's really some of Jay's Yakumo line - but Jay's seed is a different colour to my purchased Yakumo, so I don't know what's going on. Doesn't matter, it was a nice snow pea with big pods).

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