Monday, October 7, 2013

A Few Terms Defined

Big fat lettuce flowers getting ready to open up and show off
their yellow petals before the seeds ripen up.
The term “organic gardening” when it was first becoming a household word, took a lot of flak for being 'inaccurate' because “all of life is organic” and therefore it meant nothing, or so the critics said. Of course, whether or not it was accurate, the term stuck and today, no one would bother to challenge it.

Today, we talk about 'open-pollination' and hybrids and we have the terms slightly off-kilter. Wet talk of open-pollination as being the opposite of hybrid, but that's not necessarily the case. Let's start at the beginning to unravel these terms.

In the very beginning of agriculture, the selection of wheat strains from wild plants into cultivated plants produced immediate changes to the plant, including larger seed heads, larger seeds, and seeds that shattered – ripened and easily removed from the plant – occurred rapidly once the plants were being selected by humans. Over the years these changes became stable traits in the selected plants. Grown over time and having minimal assistance from humans, possessing a variety of genotypes and phenotypes (the genetics inside the plant and the physical appearance of the plant, respectively) these plants are called landraces. A good definition of landrace would be:
“... a variety with a high capacity to tolerate … stress, resulting in a high yield stability and an intermediate yield level under a low input agricultural system.” A “low input agricultural system”is the agricultural systems that are not the American mechanized, chemical stew, environment destroying agriculture and is the agricultural system of most of the world. Older strains of wheat are 'landrace wheat' – in Canada that is 'Red Fife,' in southwest America, 'Sonoran' wheat is the landrace as two examples. Landraces are the only truly 'open-pollinated' seeds grown.

The landrace might be selected by a farmer over and over again to arrive at a variety that is special to that farmer. He begins a process of 'closed-pollination' to ensure the cross is stable. Once he has a stable hybrid, we begin to call it an 'open-pollinated,' abbreviated 'op' although it probably isn't op – but it is the term we commonly use to indicate that this variety is NOT a hybrid.

But a 'hybrid' is just a cross of two different parents. Usually when we say 'hybrid,' though, we mean an unstable hybrid or a hybrid cross that has just been made. When two lines of plants are crossed, the first generation is called the “first filial” generation, abbreviated F1, a subsequent generation would be F2 and so on.

Still these are the terms you'll find in seed catalogs. OP means it is a stable variety. Hybrid means it is probably an unstable variety. A stable variety will come true if you save the seeds of that variety meaning that the subsequent plants will be very much like the parent generation. Saving seed of an unstable variety will not breed true – the resultant population will include off types that reflect the different lines of the original parent plants.

I hope this explanation helps a little bit in learning more about seed saving. I've been studying the new book by John Navazio, The Organic Seed Grower. Written for commercial organic seed production, in a world where no such book has existed, this is not a light-reading book, but boy is it chockful of information that has caused more thinking and a much deeper understanding of the vagaries of seed production. The copy I am using will eventually become a part of SLOLA's book library and I'll buy own copy – it's not cheap, but it is worth the money.


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