DIY Vegetable Breeding

9 minute read

A Highly Abbreviated (Pre-)History of Plant Breeding

Mention plant-breeding to most people, and they conjure up an image of scientists in white lab coats, peering through microscopes or pipetting substances into test tubes. With all the hype and hysteria around genetically modifying all sorts of plants and animals (and humans) the most common conception is likely this sort of laboratory-style of thing. A far cry from the reality of most plant breeding, in truth, and an even further cry from the way our food plants have been bred through most of history.

Ever since some innovative woman, wandering about the plains, digging stick in hand, gathering seeds and roots for the dinner pot decided to put some of those seeds into a patch of ground more conveniently close by her house, the overwhelming majority of plant breeders have been ordinary, grubby-fingered gardeners.

Our hypothetical hunter-gatherer lady would hardly have bothered to sow seeds from a plant that she did not hold in high esteem. She’d have gone for something that would be a family favourite. Perhaps some food that is quite a lot of trouble to harvest in its sparse natural distribution — stuff like Barley or Wheat. Much less work to gather the grain if there are lots of plants of that sort all bunched together. Or perhaps it was some highly sought after crop like Chiles that the birds tend to raid just a couple of days before their optimal harvest stage, so putting the crop close to hand where you can give it some protection (a small child wielding a stick) seems like a sensible thing to do.

I gloss over the fact that this singular act actually happened several times (probably many) in widely separated parts of the world. Clearly it seemed like a good idea to quite a lot of smart women. How it ever came about, you would hardly bother to grow plants that are easy to come by or are low value foods. No! You would plant the best you could find! So that very first act of gardening, an act that would, in time, lead us into the wild weirds of “agriculture” and “civilisation”, was also the very first act of plant breeding. The act of seed selection.

Ignorant (we assume) of any principles of genetics, and absent any lab coats or test tubes, the vast majority of the plants we eat were bred and developed by amateurs. Gardeners.

A Divergence of Ways

Thousands of years of patient growing, selecting for flavour, vigour, disease resistance and greater yield have given us this heritage of thousands of varieties of tasty, filling and nutritious vegetables. It is only in the past hundred years or so that this programme of adapting plants to our wants and preferences has been taken over by professional plant breeders. And their priorities are not our priorities.

At a minimum, a professional plant breeder is breeding vegetable varieties with the goal of profitting from the sale of seed rather than from the sale of the vegetable itself, and this immediately skews their priorities and makes their goals a little bit different from those of a gardener growing food for the table. The situation has become even more wildly divergent since the evolution of industrial-style agriculture – roughly speaking since the early 1900’s, but much more extensively since World War II – in which almost all of our vegetables are grown on large, highly mechanised and artificially fertilised farms, transported to distant markets and requiring extensive cold-storage along the way to keep the food in acceptable condition. The agri-industrialists’ demands of a vegetable variety are wildly different than a home gardener’s, to the point where they share almost nothing in common.

Now guess whose requirements are more likely to be prioritised by the professional plant breeder. The home grower who buys a few dozen or a few hundred seeds a year? Or the agri-industrialist who buys seed by the tonne? Follow the money.

By the way, this is not a moral judgement: I am not holding up one side as any better than the other, any more desirable or more virtuous. Not a bit. I’m simply pointing out that the plant breeding priorities of the one kind of grower is (must of necessity be) entirely different to the priorities of the other. And the one kind of grower represents an overwhelmingly larger proportion of where the profit lies. There’s no conspiracy to be found here, just a simple decision-tree dynamic that emerges as a natural consequence of how our vegetable foods get grown.

There are many examples of plant characteristics that are prized by gardeners that are utterly unimportant to the large-scale agri-industrialist, and vice-versa.

An Example

Some years ago I was privileged to visit the SAB Barley Breeding Institute, and was very graciously shown around the place – the greenhouses, the test beds and trial fields – by the breeders who run the whole show. It was a fascinating afternoon. The plant breeders were at pains to point out that their breeding priorities are entirely driven by the wants of the brewers who ultimately use the end-product of their painstaking work. Field-scale yields of Barley grain are important, so one of the attributes they’re constantly on the lookout for is plants with a resistance to lodging – the tendency for a stalk of grain to fall over in high winds. While we were being shown their evaluation beds – where they grow out literally thousands of strains of Barley, just one short row of each strain – they pointed to the many flattened rows of Barley stalks. The region had been blasted by strong winds just a few days before. One row, however, still stood proud, and one of the breeders showing us around got quite excited and started making notes in his little notebook that this strain should be selected as further breeding stock for just this one property. Back in their lab (yes, they do have one) they explained that among the attributes that do NOT bother about is resistance to rust funguses, a constant bane to Barley growers. The brewers’ and growers’ attitude is that they have very effective chemical fungicides to control the rusts to which Barley is prone, so it’s a solved problem, and one that needs no further effort to mitigate. An organic grower might beg to differ. Someone growing feed Barley for animal fodder might choose differently. But these good folk work for a global-scale brewing company. Different priorities, see?

Back to Our Roots

Home growers and small-scale market gardeners are an extremely lucrative market for seed producers. Profit margins are exceeded only by certain kinds of black market trade. So an important priority for plant breeders aiming to sell seed into that market is to produce varieties that are minimally suited to the widest possible range of growing conditions. So where I live, I see Onion seed for sale that I know for a certainty will not be much of a success where I live – Onion varieties that are adapted to a growing at much lower latitudes than here. But the seed companies will tell you they’re perfect for everywhere. They’re lying, of course.

Actually, there’s little to no chance of any present-day seed-seller engaging in breeding work especially for the small-scale grower. All commercial vegetable breeding is for the huge-scale commercial agri-industrial grower, and some of those varieties might make their way into small packets for the gardener. Whether they’re suitable for market gardens is often open to question. The breeding priorities include attributes like uniformity of the fruit, tough skins to better withstand machine harvesting, sorting and transport, good shelf-life, shortest time to harvest, post-harvest ripening so that the fruits can be harvested while still quite green, and predictable and simultaneous fruit production – all plants fruiting at the same time so that the entire field (or greenhouse) can be harvested all at once, washed, packaged and shipped.

Did you notice anything about flavour or nutrition among those attributes? Not a priority for the agri-industrial grower. Anything about growth characteristics under organic growing conditions? Pest or disease resistances? Nope. All handily dealt with using artificial fertilisers and pesticides.

And those will be the cultivation priorities that professional vegetable breeders will reflect in the varieties they develop.

Me? I certainly don’t want a couple of dozen Cauliflowers all heading at once, thank you, even though I do love Cauliflower. Especially home-grown Cauliflower which can in no way be compared with commercially grown Cauliflowers for flavour. I’d much rather have a variety of Cauliflower that comes to heads in fits and starts, one today, another next Thursday, and another the following Saturday. That way I can more easily cope with cooking or processing the crop without developing ‘Cauliflower Fatigue’. Similarly for almost any vegetable I can think of.

And, since I grow everything by quite stringently organic means, disease and pest resistances, pollinator attraction, and above all nutrition and flavour are all really important to me.

So if anybody is going to work on developing new varieties for the small grower, it’s going to have to be me. And all the other gardeners who share my priorities. Just the way it’s been since the very first gardeners planted the very first Beans.

And anyway, the moment you start selecting the best seed for planting next year, you’re engaging in small-scale, amateur level plant breeding, whether you know it or not. “Best” encompasses a wide range of ideas, and we won’t always agree on what’s the “best” attribute we should breed for, but it scarcely matters! Conditions in my garden, in my part of the world, are certainly different from the conditions in your garden. So we should be selecting for different criteria, and in time creating varieties that are highly adapted to local weather, local pests, local diseases or local food preferences and traditions.

Baboon-proof Carrots

For example, I doubt whether any gardening book ever published has ever considered how to deal with that notorious Carrot Thief, the local Baboon. They’ll all talk about White Fly and root rot fungus, but I’ve never encountered one that talks about pest control in relation to Baboons. And likely it’s not a concern for you. I, however, suffer from Occasional Baboons. By sheer luck I managed to breed a Baboon-resistant Carrot! It wasn’t something I was aiming for when I cross-pollinated a whole bunch of Carrots, nor was it something I was likely to deliberately plan. Who would think of such a thing, and, moreover, who else would even care? But it happened. (The secret is a Carrot with a weak stem that breaks when you try to pull them from the ground. It means the Carrots have to be dug to be harvested, but it does mean you actually get a harvest after the local Baboon has come a-raidin’.) I greatly doubt that Baboon-resistance is something any professional plant breeder is likely to prioritise.

Now if I could just come up with a way to breed Chilli varieties that get shunned by Cape Bushbuck,…

It’s All Up To Us

The point is that if we gardeners want better varieties of veg, more nutritious and tastier and better suited to our local growing conditions, we’re going to have to do the job ourselves, just as we’ve been doing for the past eight or ten thousand years. And we’re going to have to help each other, with seed stock, with knowledge and with the reasons why. Certainly the commercial seed industry is not going to help us.