Thanks, Tree,
The problem with selfing out hybrids is always numbers. Tim Peters and I have both gotten around the numbers game by growing the segregating populations in very small pots.
By growing in small containers, 2", 3", 4" and up, one can get a plant to grow quite healthily to the first bloom or two. Once one fruit begins to grow, the plant stunts inself in order to finish off the fruiting process. Pinching off any other buds or even topping the plant speeds in this procedure. The smaller the container, the more apt you will be selecting for earlier and smaller fruit. I grew out a lot of seedlings in those 72 cell trays this year and in the past. The plants literally die the cell before the fruit sometimes ripens, but give them time to cure, you can easily extract seed from a mini fruit that has at least a few seed. Hopefully, you will have enough color and shape to select for but probably not for flavor and size factors. I try to let the tray root into the ground for extra life of the seedlings.
The F-2 seedling year is important to grow out 100 or more tomato plants. With a very few exceptions, most of those F-2 plants will have a majority of their traits heterozygous, with just a few genes in the homozygous line up. It takes an educated guess as to which ones to keep. Most folks just keep seed from the most unusual types, moving away from what the F-l fruit looked like. Starting with the F-3 generation, one can grow as few as 10 plants per selection descent and do pretty well, but one should grow at least 4 plants per filial generation just to witness variation. If all four plants within whatever generation begin looking identical , you are on your way to stabilizing the prototype.
Tom Wagner
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