I've had a nice surprise with one of the F3 generation strains of the Dr. Wyche's Yellow x German Red Strawberry cross I did in 2009. Strain #4, which was a very oblate large pink with excellent flavor in the F2 generation last year - seems to be an EARLY-bearing variety, or mid-season at least.
That surprises me because both those original varieties are late-bearing, and the F1 hybrids I first grew from them in 2010 were pretty late - about 85 days from transplant into the garden to the first ripe tomato. I really couldn't tell about any of these last year as our temps went over 90 degrees in late spring and stayed there, and I didn't get a ripe tomato of any variety until 95+ days after transplanting. I've assumed these new strains were all late-bearing, and had no reason to think otherwise.
But, boy, Strain #4 this year. This early in the season, at least, it's showing a clustering characteristic - very large blossoms in clusters of 7 or 8, AND I've got little green tomatoes set on all plants of that strain. The little tomatoes are very flat/oblate as the F2's of this strain were, and I'm hoping the flavor of the F2 has carried through as well. This is only the 29th day after transplanting to the garden, and I've got no tomatoes set on plants of any other variety including mid-season ones like Big Beef.
Does anyone here know how the early/late characteristic works in tomato genetics? Apparently it's possible to cross two "late" varieties and come up with a strain that bears much earlier than either of the originals. That's news to me, but I'm pretty happy about it.
Ozark, this will be quick b'c I just haven't had the time to post here about the other genetics so here we go.
It's the genes in the DNA that determine if a particular variety is an early or midseason or late season variety.
When you do a cross, or there's an accidental cross, the two parents cross and their DNA gets contributed to the F1.
Then when you select plants from those saved F2 seeds some of parent A and some of the DNA of parent B start to segregate and we've talked about that here before and I think I gave you the link to Keith Mueller's superb website on that.
OK, so far.
Almost all genes have what are called alleles, or alternatives, such as the C gene being the gene that is a dominant gene that results in RL plants, but it's allele is c, so a variety with CC is RL, Cc is also RL and cc is PL.
So when the genes segregate and now I'm not talking about leaf form, you have the possibility of making a selection that has more genes/allels that determine earliness than what you started out with and I think that's what you're seeing.
Could two indet parents of a late midseason to late season ultimately give rise to a selection that matured earlier? Yes, I think it could and that may well be what you're seeing.
Fascinating stuff. Probably very basic to you, I'm sure, but to me it's like being in the midst of an incredible discovery. I always look forward to what my OZ x's will bring, though this year I ended up with several strange mutants, and only 2 seedlings. It will be exciting following the line and seeing what else to look for on the plants I am growing out.