You might be forgiven for thinking they are – hybrids have been blamed for everything from the lack of diversity our food system to the fall of civilization (I jest). Specifically, they are often blamed for the disappearance of heirloom varieties. The truth, though, is that practically every plant you’ve ever grown, heirloom included, was once a hybrid. If that were not the case, we’d still be stuck with tomatoes the size of currents, bitter greens, and corn that could chip a tooth. Sometimes by accident, sometimes with intent, we’ve selected for foods with more flavor and fewer toxins, flowers that were bigger, brighter, and bloomed longer, trees that grew shorter or had more interesting forms.
We use the term “hybrid” differently in the plant world than we do in the animal world. With animals, if we say hybrid, we mean a cross between two species – a lyger, a coy dog, a mule. With plants, the word hybrid may denote a cross between species, (this will be signified by an x in the binomial, as with Hamamelis x intermedia, the hybrid witch hazel) but it more often indicates a cross between stable phenotypes within a species – in animals, we call these breeds. So a hybrid beet, perhaps one bred from a parent which was bolt-resistant and another which had cool stripes, is no more evil than your Golden Doodle (your Golden Doodle may be poorly behaved, but it is unlikely to be actually evil).
Because they are a cross between two species, animal hybrids are generally sterile. But plant hybrids are not generally sterile, because they are most often a cross within a species (even the interspecific hybrids are usually not sterile, because plants are just amazing that way). That first generation of crossing – the F1 generation (F for filial) – will produce viable seed, but you’ll get a mixed lot from it. Some of the F2 generation will be just what you want, some will have stripes but no heat resistance, some will take August weather but be plain old red. So, over time, you can keep planting the seed from your heat-tolerant, stripey beet, you can rogue out the ones that do not have the characteristics you want, and eventually you’ll be producing seed that consistently gives you the plant you want. When you finally get to the place that most of the seeds produce the plant you are looking for, you’ll have what is called a “stabilized”, or standard, variety.
It’ll take time to get just what you are looking for, several generations at least. Did I mention that beets were biennial? Each generation takes two full years. Supposing you manage to stabilize your new variety in six generations, it’ll still take you twelve years to do so. Time is one reason we often stick with F1 hybrids; another is “hybrid vigour”. That initial out-crossing of genes creates a plant that grows bigger and is more productive than the parent plants – by a lot.
Here’s the total yield of a single sweet dumpling squash plant, a standard variety –
Here’s that sweet dumpling squash hybridized with a mini-pumpkin. These all came from a single F1 plant.
In addition to saving you years of patient breeding, and giving you plants that are consistently better producers for your three dollars per packet, plant breeders are doing us one more service when they maintain F1 hybrid lines. They are maintaining two lines of standard (heirloom, though that’s a fungible term) varieties every year, in order to have parents with which to produce those hybrids. They are protecting genetic diversity. Plant breeders, particularly small ones who specialize in regionally appropriate plants, are the good guys, and they deserve a hat tip.
A poem, from Wendell Berry, for seeds, those who coddle them, and those who plant them.
The Seeds
The seeds begin abstract as their species,
remote as the name on the sack
they are carried home in: Fayette Seed Company
Corner of Vine and Rose. But the sower
going forth to sow sets foot
into time to come, the seeds falling
on his own place. He has prepared a way
for his life to come to him, if it will.
Like a tree, he has given roots
to the earth, and stands free.
Wendell Berry’s “The Seeds” can be found in Wendell Berry, New Collected Poems, by Counterpoint Press. http://www.counterpointpress.com/dd-product/new-collected-poems/
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