In the 1980s Frank Morton began as a farmer of mixed salad greens with a budding interest in saving seeds when he discovered one red lettuce among many flats of seedlings of green leaf lettuce. This unintentional cross of red romaine and green oakleaf piqued his curiosity and launched a lifelong vocation of innovative classical seed breeding. Frank and his wife Karen have since moved on from the salad business to devote themselves full-time to Wild Garden Seed, which provides organic, open-pollinated salad greens and vegetable and flower seeds bred specifically for organic farming systems. Frank Morton has bred over 100 unique plant varieties. In this interview with Arty Mangan of Bioneers, Morton offers insights into the fascinating world of seed breeding and explains why classical seed breeding has an evolutionary biological advantage over genetic engineering and gene editing.
ARTY MANGAN: When breeding seeds for new traits such as flavor, resistance to pests, resilience to weather extremes, etc., what are some of the fundamental considerations?
FRANK MORTON: Whenever people have had to move from a favorable climate to a harsher one, they have had to adapt their seeds to that new climate. If you want to breed seeds for some trait or resistance to stress, then you’ve got to have the environment to breed it in, and so in some sense you’re always a little bit behind the curve, unless you’re able to think ahead and do your breeding under a stressful situation that mimics the stresses you are anticipating will prevail in your environment in the future. I’ve always believed that the best way to grow and breed plants is under low-input conditions in which the plants are under a little bit of stress, so they are forced to use their genetic potential to survive, so, for example, if you want to know which plants have resistance to disease, you grow them in a nursery that’s full of disease. If you want to know which plants can do well under low-input, high-stress conditions, you breed them under those conditions, such as a lack of irrigation or minimal irrigation, or intentionally not having your breeding ground be fertile, or any number of similar parameters. In that way you’re breeding for resilience to stress.
ARTY: How does that approach differ from the way genetic engineering breeds new varieties?
FRANK: The biotech seed companies claim that by using genetic engineering and inserting a new gene aimed at a particular trait, they can produce plants resistant to specific stressors. I don’t think a single gene can accomplish that in the overwhelming majority of cases. Genomes are incredibly complex, and nearly all of a living organism’s responses are polygenic, i.e., they involve multiple genes. As a plant breeder, you should be selecting the whole organism. That’s my opinion, and I know there are a lot of plant breeders who would agree with me.
ARTY: Genetically engineered GMOs have been controversial for a number of reasons, one of which is that they are approved without having to conduct long-term safety trials. Now with newer gene-editing technologies such as CRISPR, the promise by the biotech industry is that it their new methods are more precise and safer.
FRANK: What hasn’t changed at all, even in light of CRISPR, is the falseness of that promise. Much to the surprise of CRISPR fans, it is emerging that often changes to “a single gene” in a plant have unexpected impacts that are way off target. For example, in the case of sweet corn breeding, there is a gene involved in conversion of sugar to starch. In the CRISPR mindset, this is a target gene to “knock out” in pursuit of sweeter corn that doesn’t get starchy after harvest so that it can be shipped long distance without losing the sweet crispness of fresh picked corn. It turns out, though, that the plant has multiple copies of this gene functioning in different tissues of the plant, and it is essential that most of those copies continue to function for the plant to be healthy. “Knocking out” that specific gene turns out to not be nearly as clean as it sounds, because you may want to “edit” it out of the developing seed tissues for the desired effect, but not from the leaves, stems, and elsewhere. That requires a much more accurate “address” for editing than first impressions of the technology would suggest. Plant genetic function is much more complicated than CRISPR proponents wish to concede. Years into it, those researchers are still babes in the genetic woods, but, meanwhile, traditional plant selection still works very well to improve plant performance, as long as we engage with plants as partners in the process and do it in the real world. That’s the time-tested method.
ARTY: Miguel Altieri of UC Berkeley, one of the world’s longtime thought leaders in the field of Agroecology, has said that some genetic engineering interventions could result in unintentionally “turning off” other genes and actually reducing plants’ capacity for resilience and adaptability.
FRANK: That’s a good point. In organic plant breeding, when breeding for durable resistance, one strives for “horizontal resistance,” the opposite of “vertical resistance” (which is single gene resistance). With vertical resistance, for example, there’s one gene that prevents downy mildew from making lettuce sick. That gene corresponds to a gene in the downy mildew; in fact, it’s called “gene for gene” resistance, but when downy mildew evolves around the one resistance gene, then the whole organism becomes susceptible as soon as that one gene is overridden or gone-around by evolution. So, if you had used genetic engineering to insert this one vertical resistance gene to prevent downy mildew, that disease organism might evolve to bypass that gene, and you wind up with a weaker plant than if you hadn’t intervened at all. Horizontal breeding, on the other hand, involves breeding for polygenic disease resistance. It’s aimed at strengthening the whole plant and its entire complex genome, not just one gene to support resistance to a specific disease. As a traditional plant breeder, I select the whole organism because many genes contribute to resistance, so pests can’t evolve around the defenses as easily.
ARTY: When you select a plant for certain traits how does that affect its future generations?
FRANK: Rutgers University did a study some years ago with radishes that were genetically identical. One population of radishes was exposed to leaf-eating caterpillars, and the other population was not, and they saved seeds from each population. The offspring of the plants that had suffered herbivory in the parental population germinated with hairs on their leaves and with higher levels of anti-feeding chemicals in their sap. Some genes had obviously been turned on in the parent generation, and the offspring germinated with those genes functioning.
ARTY: So, the response to the stress carries forth to the next generation?
FRANK: Yes, and as long as the stress continues to be a part of the environment, then that gene will carry on expressing that obvious trait in the organism. If that stress goes away over time, selection will direct the organisms to turn that gene off and save energy. Making protein for the genes takes energy, so not all genes are expressed all the time.
ARTY: Would you say that plants have a kind of genetic toolbox that allows them to respond to environmental conditions?
FRANK: Plants have always been flexible. There’s something about the way plant genetics work that’s a little different than the way animal genetics work. Animals (including humans) don’t have as much untapped potential that they can turn on in a stressful situation. We’re just not the same in that way. We express most of the useful genes that we have, whereas plants don’t express most of their genes. Plants typically only express about a third of their genetic potential under normal conditions.
ARTY: Does that mean that plants are able to respond evolutionarily more rapidly than animals, including humans?
FRANK: Well, they have to respond without changing location because they can’t. They have to stay where they are and use their genetic potential to adapt in place. Animals, more typically, move south or north or up or down in elevation, when under stress, so the mechanisms of adaptation are different.
ARTY: Much of the general public has lost touch with natural processes and is unaware of the genetic information and potential contained in something as small as a seed.
FRANK: Most people just don’t know where seeds come from. When my sister-in-law found out that I was growing lettuce seed, her response was: “Lettuce has seeds? Where are the seeds in the lettuce.” She’s trying to imagine where inside her iceberg head the seeds are. That’s where a lot of people are at. They just have never thought about the fact that nearly every plant they eat, every plant they come in contact with, all come from a seed. Weeds just appear. People don’t realize that weeds come from seeds. Imagine a world in which, when the ground was made bare, nothing sprouted. If there weren’t weed seeds in the soil, we would be in so much trouble. I think weeds are a blessing, and they are a great job creator. I think of weeds as nature-enforced cover-cropping, and I use them that way.
Most of our food comes from seeds. The creation of agriculture depended on the domestication of seeds. Being able to collect and store the seed and to plant it next year, was the first agricultural act after the time of hunter-gatherers. People had to learn how to select and store wild seeds. One of the next challenges was the elimination of dormancy in seeds. Take wild lettuce for example: if you plant wild lettuce, it doesn’t sprout like lettuce. It’s dormant, just like all wild plants. If you take any domestic lettuce and plant it, it grows right up. If you ever work with native seeds, you’ll find that it’s nothing like gardening. It’s really a puzzle to get native seeds to germinate when you want them to. The whole history of agriculture is based around the domestication of the seed and the plant that produces the seed, making it something that fits your lifestyle and provides the kind of food you want to eat and survive on where you are living.
When I was around 5 years old, I was in West Virginia, and the biggest treat that I remember was watermelon, and I knew that watermelon came from watermelon seeds, and the damn thing was full of them. It occurred to me that I could have all the watermelon I wanted if I just kept those seeds and planted them. Where the hell that impulse came from, I have no idea, but that was my first seed impulse. So, I went out and I tried to plant those seeds out by the garage. It was my first agricultural act. Of course, they didn’t grow past seedlings. It was the middle of summer and no way was it going to work, but it didn’t matter. The next year my dad helped me plant a garden.
I think that seeds are something that traditionally we humans pretty well understood, but in our modern world, the seed is the most mysterious part of our agriculture. Nobody thinks about it—where it comes from, how it’s grown, what’s important to know about it. In commercial seed production, there’s a lot of arcane knowledge that only the people who do it know. It’s like a secret order of knowledge, almost, because so few do it anymore, but there must have been a time when everybody kept some seeds, if only for their garden.
ARTY: The place of origin of seeds is also something the general public knows little about. From ancient times, seeds were exchanged farmer-to-farmer, region-to-region and ultimately globally.
FRANK: The geography of seeds is an interesting question. Spinach, for example, started in the Middle East in Iran, and some varieties went east and some went west. The ones that went via the Afghan/China route and eventually ended up in Japan look quite a bit different than those that went the other direction and ended up in Amsterdam and then in the United States. The leaves are a different shape. The Western style is like our Bloomsdale spinach; it’s dark green and has sort of rounded leaves that are under-cupped and very thick. The seeds are round, not at all spiked to the touch.
The seeds that went the other way that ultimately ended up in Japan, the leaves of those plants are much larger and flatter. They’re a lighter shade of green. They’re way more productive. Each plant makes more spinach. They don’t have the same flavor. They’re not as meaty as western Bloomsdale types that have a very thick texture. The Japanese and Asian varieties are thinner; they’re more “lettucey.” Interestingly, the seeds are spiked with spines all around the seed. If you had a handful of them and squeezed them, they would hurt your hand. They are precisely the same species as Bloomsdale, and yet the seed itself and the human hands that selected them are so different. I wonder why the Asians put up with all those pokey seeds that hurt. Maybe it has to do with seed predation by birds; the spikes may act as a deterrent. It’s just so interesting. The carrots that went through Europe to Amsterdam are orange and crisp, and we often eat them raw. The carrots that ended up in the Far East are not that good raw. They’re chewier. They’re not crisp and crunchy. They’re excellent when they’re cooked. Think about the cultures that selected them. In China, when these crops were being developed, nobody ate raw vegetables. Farmers used nightsoil (composted human manure) as fertilizer, so their public health realities encouraged the cooking of food.
It’s not that way when you go the other direction around the globe. Everybody eats raw vegetables, and if there’s E. coli in your soil, people get sick. It’s interesting the way the culture and the plants interplay, and it’s still going on today. Chefs make a lot of what is possible and successful for the organic farming community. The chefs understand different varieties and the excitement of new flavors and textures and possibilities of food. And plant breeders get it too. Plant breeders work with seeds, and have the fun of breeding new forms, flavors, and colors. They also understand the agronomic advantages of certain traits, such as a carrot that can grow without splitting or that has a top that is strong enough so that you can pull it out of the ground by the top. That’s an important trait if you don’t want to harvest carrots by digging them all up.
All of that is mediated through the seed. Why does the seed express a trait? It expresses it because the people working with that seed want a certain thing, and they select for it. And often, the plant naturally provides a diversity of choices, so the answer to the question “where do seeds come from?” is to a large extent that they come from our desires. What does Monsanto/ Bayer want in a seed? Total ownership, total profits. But what do you and I want in a seed? We want freedom, the freedom to operate, the freedom to grow our own food, to be happy and not obliged to anybody to eat want we want, so what’s in the seed is actually a reflection of the values of the culture that created it.
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