Saving seeds for next year

F4 Photo updates

Only a genetics nerd...

... would do a Bayesian on this...

From my 28D3 F4s, (red cherries) none have the gf phenotype.  What are the odds that any are gf/+ and thus might have some gf/gf progeny next year?  Bayesian analysis to the rescue...

The F1 plant was gf/+.  F2 plant 28D was not gf phenotype; therefore it's prior probability of being gf/+ was 2/3.    Four F3 plants were grown last year; none had gf phenotype either.  28D3 was one of these.  What are the odds that 28D3 still could be a gf/+ carrier?

Hypothesis	Assume F3 = carrier	Assume F3 = non-carrier
Prior	4/9	5/9
Conditional (prob that all 3 F4s are non-carriers)	27/64	1
joint	0.141	5/9
posterior	(0.141)/(0.141)+(5/9)=0.202

Therefore the posterior probability that the F3 plant,  28D3, was a gf/+ carrier is 0.202.

Given this, the probability that any particular one of the 28D3 F4 plants is also a gf/+ carrier is = 0.202 x 2/3, or ~ 0.135 = 13.5%.    

Notes on F4 plants, etc. 7/24/18.

Passing the peak phase.   While the F4 plants at the farm pretty much accomplished my goals, it was interesting that those plants really struggled to grow large this season. None of the “beefsteak” F4s there – these were 8A, 46A, 55A, 10B - grew taller then about hip height; many of them are sort of dying off, and no so much catastrophically wilting but simply failing to grow while the rest of the plant kinda dies naturally; the growth was really limited.   I think it's mainly due to the late start.  Weather has been hot, but not overly dry.   Nevertheless, I got fruit, and saved F4 seeds from several 55A and 10B subline plants. In contrast, the 28D3’s (cherry size fruit) grew into very vigorous plants with lots of fruit.  Also saved seeds.

So.  Sublines 8A turned out to have no purple, so I am not pursuing these any more.

Sublines 55A has pretty strong purple, mostly, and good size, so I am saving several of these plants.

Subline 46A2 has similar phenotype to the F3.  Have two at home in containers, both of which had nice fruit set and I have saved seeds from the first one with ripe fruit.

Line 10B1 was interesting for a few reasons.  This F3 was not gf, but was large and purple so I saved it.  Turns out it was definitely gf/+, as one of the three F4’s is gf/gf, and so this one will compete with the 55A sublines as having gf/gf ; purple ; large size.    One F4 was large and ripe but had no mature seeds (!); later fruit from same plant had some, but few, seeds despite a nice beefsteak.  And one F4s turned out to be y/y as well as purple    So I have saved these too.

The two 46A2 plants in containers at home did MUCH better than at farm and are still going.  The 55A7 in a hay bale died of wilt, but grew to about 6 ft first and had good fruit set, though most fruit did not ripen before the whole plant died.   

The 28D3 F4 plants were interesting for their slight differences. All three were red cherries like the F3 parent.  However, #2 had more cracking and diseased fruit than #1 and 3, which were pretty much crack-free.  #1 and 2 avg. about 10 g, while #3 is ~12g.  #1 and 2 have no visible purple but #3 has just a tiny bit.  So 28D3.3 is the one to pursue.

Other notes:

The container plants are much better in terms of health and disease protection than hay bales or in-ground.  But the fruit was prone to end-rot.  Flamme and Green Zebra were most prone to this problem. Fruit set on KB and CG was poor.   

GDZ really seems just like RT to me.   GDZ is advertised as having fruit that mature more consistently than RT, but I’m not really convinced.

"Pink" fruit, epidermis pigmentation - the y gene

I've not really tracked the pink epidermis gene in my crosses, but I've realized that I should.  Here is a link to the outstanding Frogsleap Farm web page that explains it in detail.

"Pink" tomatoes are homozygous recessive for mutations in the y gene, which is necessary for yellow pigment accumulation in the fruit's outer epidermis.  Classic "tomato" colored tomatoes are wild type.  "Pink" varieties are slightly pinker than the standard red ripe tomato, which is a little orange-red.  It's pretty useless to really compare online images of pink and regular red tomatoes unless they are together side-by-side in the same photograph.

Frogsleap farm reports that Cherokee Purple, Green Zebra and Brandywine are y/y.    (A few years ago I grew Pink Ping Pong, but found it unremarkable.)   Since CP is y/y though, this suggests that "pink" was segregating in my IR x CP F2s, but sadly I did not pay attention to it, and I don't know yet if any of my saved F2s were y/y.   I think the answer is no.  However, there's a decent chance that the y allele was still kicking around in the F3s, so some of my F4s might be y/y.

Example below of +/+ and y/y skin:   A 28D3 fruit is clearly +/+, vs "Carbon" which is y/y (just ripe today).

Crossing progress update

As of about July 7, I counted 11 growing fruit from successful cross-pollinations.  3 others had end rot or broke off accidentally.  Total attempts to date: about 71 I think though not all got assigned serial numbers.  So the success rate is about 20%.

Three places for tomatoes

Comparison: week of July 4, 2018.
Patio containers; bales; farm plot. Lush; wilting; and slow but steady.

Harvest season starts. F4 generation fruit.

Finally seeing some ripe F4 fruit.  Still seeing clear phenotypic variation within progeny of individual F3s.