Healthy soil and sustainable growing

[yarrow@sfo.com]

Title: Re: [Livingontheland] hybrids

At 8:57 PM -0600 2/7/10, Emery Mitchamore wrote:

This  note caused me to realize that I don't understand the difference between hybrids that don't produce viable seeds, those whose viable seeds don't reproduce the characteristics of the parents, and the products of (often many generations of), cross-breeding, such as mentioned below, that DO reproduce the desirable characteristics of their parents.  Can anyone explain this to a non-botanist?

>>

What I know from growing tomatoes (open-pollinated as well as a few generations of hybrids) and reading tomato-growing forums:

-- open-pollinated (OP) tomatoes will breed true from one generation to the next. They may have come about as a selection (look! this one tastes the best! let's save the seeds!) in a field, or as a random mutation, or as an intentionally created hybrid that was then dehybridized (see below). But at the same time, random mutations can occur, and if you're growing a lot of one OP tomato variety and see one plant that stands out for some reason, you can save its seed, select plants from the next generation, and create a new OP tomato variety. (I think this is how the Wild Boar Farms tomatoes came to be -- lots of wild color patterns.)

-- according to many tomato experts, it's a myth that hybrids don't produce viable seed or won't produce good tomatoes. I believe the standard gardeners' reference on this is a book by Carol Deppe on growing your own vegetable varieties.

-- it's possible to dehybridize tomatoes, that is, grow a hybrid, save the seeds, select the best ones (that is, the ones whose qualities you want) each season, repeat 3-4 times. The hybrid seed and the first crop of fruit is the F1 generation. Seeds saved from an F1 tomato are the F2 generation. So you plant the F2 seed, and if you like what you get, then from the F2 fruit you harvest F3 seed. By F5 or F6, you start to get some stability, which means they breed true.

If you're looking for an OP version of a hybrid, then you grow the F1 seed each year, too, so that you can compare each generation of saved seed to the "goal." If you're simply looking for a good-tasting tomato, you can make your selection based on size, color, earliness, disease resistance, etc.

Someone else at the community garden grew several dozen Sunsugar F2 seeds last year, thinking they'd breed true (the F1 is a gold cherry tomato), and I heard that most of the people who grew them got spitters, some of which were red. But an OP version of SunGold F1 is being developed in Germany.

I've grown several F2-F3 seeds from other tomatoes, and gotten good but not great results so far. For some tomatoes, the F2 is close to the F1. For others, it can be anything. Lots of segregation occurs with the F3 (meaning, you can grow 5 plants and get lots of variety). I grew a few plants of an F3 last year and got one plant that produced overly seedy fruit with a so-so flavor, and one plant that produced pretty good tomatoes, so those were the seeds I saved.