Cold tolerant tomatoes, right down Joseph's alley.

[Joseph Lofthouse]

2016-03-07: Sprouting today in the cold/frost tolerance test are: Current tomato from last year's cold tolerant trial, Brad my long term earliest tomato, and LYC 2822 another S. peruvianum accession.

[Joseph Lofthouse]

2016-03-08: Matina is sprouting in the cold/frost tolerant trial. It was one of my favorites from the original cold/frost tolerant trial that I did a few years ago. It wasn't particularly frost tolerant, but it grew well in cool weather, and set fruit early. It was overshadowed by Jagodka's productivity during the second growing season, so I used Jagodka for making crosses.

2016-03-09: HX-9 is sprouting. It has Jagodka and Hillbilly (or Virginia Sweets) as ancestors.

[steev]

I must admit to being more concerned with squirrel-resistant varieties than cold; I fear I'm becoming cold-deficient.

[Joseph Lofthouse]

Mar 9, 2016 22:45:08 GMT -5 steev said:

I must admit to being more concerned with squirrel-resistant varieties than cold; I fear I'm becoming cold-deficient.

If I ever get around to working on squirrel-resistance, I have the perfect field to run trials. The only time I ever grew tomatoes in that field, every fruit was picked green: when about the size of a shooter-marble.

[Joseph Lofthouse]

2016-03-10. Sprouting are; Tomatillo, Wild-X Orange, Blue Beauty.

2016-03-11. Sprouting are; Early Appple, Joseph's Landrace, Lyc 2885 (S. habrochaites), LX-10 (descended from Jagodka and unknown pollen donor), Cold Hardy Slicers from last year's trial, HX-13 (descended from Jagodka and Hillbilly or Virginia Sweets).

[samyaza]

Joseph, I'm glad to hear of Matina. It's been on the "best of the both worlds" side for me for about 20 years. Just a bit too small, to my opinion.

[Joseph Lofthouse]

Today I potted up two sets of plants from the cold/frost tolerant trial. There were a total of 16 plants in each set. I added S. habrochaites, and S pennellii which I have been growing separately. That filled up the 18 cells in my trays. I'm intending to keep one set of plants alive through the summer, so that regardless of whether I get 100% kill rates, I still have samples of the varieties that germinated in the coolest weather. I chose the largest plants in each variety, which roughly corresponds with the first to germinate.

The forecast is for about 14F in about 5 days. It won't get that cold in the greenhouse, but it will get colder than freezing. The forecast shows progressively colder each night till then, so I may just watch, and add protection after about 1/2 the plants die?

[samyaza]

Mar 13, 2016 22:32:47 GMT -5 Joseph Lofthouse said:

The forecast shows progressively colder each night till then, so I may just watch, and add protection after about 1/2 the plants die?

Of course it will give a clue of a frost tolerance, but I suppose transgressive segregation could accumulate more :
1 - Make a cross for every combination of accessions.
2 - Grow these (uniform) F1 seeds.
3 - Cross them in every combination again.
4 - Select hard for frost resistance, leaving only a fraction of them go to flower.
5 - Repeat 3 and 4 until you can't accumulate more resistance.
6 - Stabilise your new variety to keep it true to type, while maintaining selection pressure. It'd be a shame to let it get lost.

The more accessions you recombine, the more plants you grow beginning from point 4, the more recombinations you'll get. And the more chances of finding a superior recombinant you'll have. Of course, you'll need a huge number of plants. And this is only for frost resistance. You'll also have to select for yield, quality and agricultural suitability. You'll get tons of poor yielders, horrible tasting and unmanageable plants during the process.

[Joseph Lofthouse]

Mar 14, 2016 4:01:10 GMT -5 samyaza said:

The more accessions you recombine, the more plants you grow beginning from point 4, the more recombinations you'll get. And the more chances of finding a superior recombinant you'll have.

The more I work on the cold/frost tolerance project, the more apparent it becomes to me that it should eventually be merged with the promiscuous pollination (semi-outcrossing) project, and eventually into the self-incompatible (mandatory-outcrossing) project. This will allow the plants themselves to auto-generate huge quantities of randomized genetics. It's easy to trial lots of seedlings. It's lots of trouble to keep records of what has been crossed with what. My plant breeding strategy is almost always to skip the record-keeping, and the manual crossing steps: To arrange things so that the plants themselves tell the story and make the crosses.

So my manual crossing goals for this year are to focus on crossing the most frost tolerant lines with the most promiscuous lines. Eventually, I expect to stop growing any variety that doesn't have open flowers. It was painful when I stopped growing potatoes that failed to produce fruit. But today, I sure am happy with that decision.

I'm also planning on putting in a crossing block of all the self-incompatible species that I have acquired, and letting them mix things up by themselves. I expect to plop some domesticated tomatoes with open flowers into the middle of those plants. Be interesting to see what random crosses might occur. Sungold F2+ will be among those varieties, since some of the descendants already combine good cold tolerance with exerted stigmas.

[samyaza]

I remember reading about self-incompatibility in wild tomatoes species. I experimented it myself in a cross with S. habrochaites ; self-incompatibility is a dominant trait. The single F1 hybrid I tested needed manual pollinisation to give fruits, because it was the only outbreeder around.

[reed]

It hasn't been cold here like it should be but still not near warm enough for tomatoes (at least in my experience) but about twenty or so came up in a pot of dirt that I was using as a stop to hold a log in place. Yesterday morning there was a light freeze and about 1/3 of them croaked completely, the rest look perfectly fine. The dirt in the pot came from the compost pile and apparently must have had seeds in it from last falls clean up. Have no way to know what they might be but I grew several of Joseph's last year. Maybe they will be turn into the earliest tomatoes I ever had.

[kazedwards]

Not that I'm doing a cold tolerance test or anything but yesterday I potted up some of my tomatoes. The seedlings that were extra I planted out by the compost. I figure with the unusually warm spring they might have a fighting chance. It has been getting below freezing a night or two every week and lows in the 30s-40s otherwise.

[Joseph Lofthouse]

I put the flat of tomatoes for the cold/frost tolerance test outside into a snowstorm for 8 hours today.



And a high resolution photo.:

[steev]

And the result of tough love is?

[darrenabbey]

I had a flat of tiny tomato plants survive that sort of snow-fall, but I assumed it was because I immediately took them in for thawing.

I do wonder exactly what would be needed in terms of equipment to do such selections in a less haphazard way than depending on the weather.