I'm working on early lines bred from old standard, heat-setting, Midwestern university varieties. So far the results are 2-1/2" to 3" red canners, slicers, or "salad" tomatoes. The earliest so far are 120 days from direct seed to full ripe average in the first fruits, or about 66 days DTM from transplanting 7-week-old starts.
I started with a determinate cultivar from University of Missouri that has an 80 DTM from transplant average every time I've grown it, and crossed to a heat setting indeterminate from University of Nebraska said to have a 70 DTM from transplant.
The F1 in 2010 made full color in about 72 days from transplant. Then this year, several of the F2s made a 65 - 68 day trip from transplant to full ripe.
The heaviest yielding, earliest, and longest yielding F2s were all what I would call semi-indeterminate with regular, uninterupted sets of 3 and 4 fruit per truss every second or third internode. I'm calling it semi-ind. because most of the sets were in the 2nd internode, while some of the sets were directly opposite the 3rd leaf node above the previous set. The fully determinate F2s were a bit disappointing in the yield department.
After asking a couple of people who should know, I was told it's not unusual for the offspring to go earlier than either parent. I don't know if this is a result of hybrid vigor, or if the earliness will persist down thru subsequent generations when open pollinated. However, this year I outcrossed the F2s to an even earlier subtropical determinate from IFAS to try for 60 - 65 day F1s next summer.
|