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to the Organic Broadcaster: "The Seed We Need:
Breeding plant varieties for organic agriculture" Why plant organic seed? As organic growers, our answer to this question goes much deeper than supporting organic agriculture or following the National Organic Program rules. If we are looking for plants that produce good crops despite cold soils, drought, weed pressure or excessively wet conditions, we need to encourage organic plant breeding systems. Basically, a seed produced organically has already proven itself capable of thriving on our own organic farms. "We are breeding for the challenges of organic cultural techniques," said organic seed breeder John Navazio, the director of seed grower development and seed research at the Abundant Life Seed Foundation. Navazio is also the co-founder of Seed Movement, an organic seed company "devoted to regional testing under less than ideal conditions." Breeders and farmers with Abundant Life and Seed Movement collaborate to develop varieties for seedling vigor, cold soil tolerance, efficient nutrient uptake, durable resistance to disease, and good seed-producing ability. Another company dedicated to organic farmer-breeder collaboration is Seeds of Change. Micaela Colley, the manager for the Seeds of Change New Mexico research farm, notes that "oftentimes with commercial breeding they get so focused on certain traits--size, yield, uniformity--and it's not a real holistic method." For example, regarding traits important to organic growers in May and June--seedling vigor, competitiveness at a young age, or disease resistance--Colley said "(commercial seed breeders) have answered those questions by forming an alliance with the pesticide industry. You get your coated seed and you don't have to worry about damping-off at an early stage. So it's a matter of the focus of what you're breeding; most of the breeding in the last fifty years is focused on what's desirable for large-scale industrial agriculture." John Navazio notes that, because vegetable seed is a very high value crop, conventional seed growers use a lot of chemicals to make sure they get a marketable yield. "They baby it with fungicides. A lot of seed production fields are fumigated with methyl bromide. Once you hear about conventional seed production, you'll never want to buy another conventional seed again," he said. "They have really created varieties that have been selected and bred to excel under high-input chemical systems." Navazio sees this as a great advantage for people who want to select seed for organic production. "The seven or eight large transnational seed companies want to grow organic seed for the money, but they have no commitment to organics," he said. " They aren't thinking, 'how will this variety fit into an organic production system.' They're thinking 'where's the new organic rules? What kind of stuff can I put in the spray tank under those rules?" So small seed producers can prosper by developing better varieties than the large companies offer. "What we're doing is like David and Goliath," he said. "But I think if we do a good job, breeding things that work well in organic systems and producing good quality seed, hopefully there will be a market. It's like a lot of organic marketing: 'give a face to the people who are really doing the work.' Get people to know who it is producing the seed, and tell the story of how it is produced." A new paradigm
in seed breeding As an example of plant architecture, Navazio discussed his work with carrot varieties. "We've seen a huge difference in how fast carrot tops grow from different varieties," he said. "One old carrot variety, 'Western Red', from Queensland, Australia, is persistent, very thick and tall, and puts on growth really quickly." The "architecture" of quickly-established, tall, thick foliage creates an advantage in competition with weeds for sunlight. "You only have to do one weeding early, and then you don't have to weed again," Navazio said. He noted noted tremendous potential for labor saving, as even large organic producers in California now do two hand-weedings for carrots, with migrant crews. Another old
"workhorse", 'Golden Jubilee' sweet corn, is still important
to large-scale organic producers because it provides reliable natural
resistance to damping-off. "Because it is not narrowly inbred,"
Navazio said, "it has more genetic variation for cold soil
tolerance." Navazio noted agronomy professor Bill Tracy's research
at the University of Wisconsin has found a lot of variation in corn
varieties for ability to emerge from cold soils and ability to grow
vigorously early in cool conditions. "We can breed for nutrient
uptake in cold soil. Phosphorus is really hard to get ahold of early
for heat-loving plants," Navazio said. "There is also
not as much available nitrogen, so it's really hard to get your
stand caught up." This creates problems during processing,
when uniformity is necessary. Each mutation of the disease is called a race. "Last time I checked, in soybeans we are on the 28th race of resistance to phytophtora that soybean breeders are dealing with," Navazio said. "What happens is you've set up a 'race race', where breeders spend 3/4 of their time getting a new gene of resistance to the new race that has overcome the old resistance. That's vertical resistance-you keep stacking one new gene for resistance on top of the other because the disease keeps overcoming." By contrast,
"horizontal resistance" is "the equivalent of a good
immune system in the response (to disease)," Navazio said.
"The cuticle of the leaf surface is a little bit thicker, the
biochemistry of the leaf is a little different; the disease will
grow very slowly compared to a really susceptible plant. Sometimes
the lesions never sporulate and make disease." Instead of selecting
a specialized gene for a specific disease, breeders can choose an
array of general-purpose "housekeeping genes". Housekeeping
genes determine structures and functions like cell wall, leaf cuticle,
stomates, leaf hairs, etc., all of which can help determine how
susceptible or how resistant a certain plant is to a disease. "It's
whole organism plant breeding," said Navazio, "and the
most beautiful part is it's durable; it doesn't break down when
a new race comes along. It holds its resistance to all races of
a pathogen." With horizontally-resistant varieties, growers need to accept that their plants may suffer a low level of disease. "We have been so conditioned to look at resistance as being complete immunity," Navazio said. He presented slides of his work developing spinach varieties, which showed a thick bed of spinach plants that he had infected with downy mildew--light green to yellow leaves, with fluffy gray fungus on their undersides. Navazio judges individual plants on a disease rating scale of one to nine, with one being "hammered" and nine being no disease. After several generations of selecting and breeding he is able to reliably grow "sevens", under heavy disease pressure, which have small, intermittent lesions on their leaves--good enough even for salad mix. "I'd love to give you immunity, but if you have downy mildew, that's darn good," he said. Stepping
forward into the past--farmers breeding seed Podoll notes that most modern wheat varieties have been unable to maintain vigor or yields for longer than five years, due to their narrow genetic base. "Even certified seed seems to run out," he said. "The breeders start selection pressure too fast and don't allow recombination to happen (with other varieties) when they do cross-breeding." As with vegetable varieties, conventional breeding conditions for wheat exacerbate the problem for organic wheat growers. "Very few new varieties are coming out that meet the quality criteria demanded by farmers and the organic industry," said Podoll. "When (earlier) varieties failed we began to recognize that they have been selected and bred under high-input conditions--a lot of fertilizer, herbicide, and pesticide use. They're very dependent on perfect weather conditions and supplies of readily soluble nitrogen. It just stands to reason that we should instead be breeding under the environment in which the grain is being grown." Podoll said that organic farmers have managed to keep some older varieties going. He raises 'Coteau', a 1978 release that stands well under drought conditions. "It's a tall wheat with a deep root system, so if it's dry out I can plant that seed three or four inches deep and it'll come out of the ground. Its coleoptile length genetically will allow it to break the soil surface. Whereas modern dwarf wheats have a coleoptile that can grow no longer than a couple inches, so if you plant it deep it doesn't have the genetic capability of emerging." Podoll illustrates his ideal for a grain "workhorse" variety by telling about a proso millet, 'Crown', that his family has grown and saved every year since 1953. When it was developed around 1939, Podoll says, it yielded fifty bushels per acre. "This was almost unheard of at that time, that any grain--even corn--could produce that quantity." He says that the millet can still yield the same amount today. "It is unaffected by disease," he said. "It produces a quality grain no matter what; if it doesn't rain and you only get six bushels per acre, it still produces a 56 pound bushel. If it gets hailed on in the middle of July and regrows to six inches, it's still going to produce 56 pounds or more per bushel. I've had it kill Canada thistle on my farm, it's so vigorous." Podoll sees this millet as a model for breeding today, because selection for yield has not diminished the plant's natural hardiness. "It has an inherent toughness, hardiness, and integrity," he said, "that can withstand whatever Mother Nature can throw at it, not only in a given year but also over fifty, one hundred, and two hundred years. That's what I'd like to see in wheat, corn, oats, barley and other grains. It's really, in my mind, the perfect mix between wild qualities that you'd find in a wild grass and what we need for our domestic use." Podoll and other organic farmers in North Dakota are now assessing oat and wheat varieties in field trials, but they will need to find funding before they can begin actual breeding. "Selfers (self-pollinating grains) require an extreme amount of handwork," he said, "because there's only a two percent to three percent natural outcrossing." Besides the grain trials, Podoll and his family produce and develop organic vegetable seed for Seeds of Change. Over the last seven years they have gradually increased the vegetable seed crops which work well for their farm: tomatoes, corn, beets, pumpkins, cucumbers, and watermelons. "It's good for a small farm like us," he said, "because it's all handwork and there's very little overhead--it's just our labor and the land." Over the years, Seeds of Change has developed a network of farmers across the country to produce and develop their seed. Micaela Colley sees this network as the heart of their company. "Our approach to breeding has always been on-farm," she said. "It's on real organic farms that you are going to have the kind of selection pressures you need to develop organic varieties. If you've got weed competition, (you want) the ones that are vigorous enough to overcome that. If you have a damping-off disease situation, the half that survive are going to have some pre-disposition to handling those conditions. So we feel that just by having all of our varieties grown year after year after year on organic farmer's fields in different regions, over time they start to develop characteristics that make them better adapted to an organic environment." Colley also sees important social and agricultural advantages for farmers in seed breeding. She suggests that friends and neighbors develop local exchanges, similar to the one David Podoll is involved in, where they can divide the breeding work and share information. "It's a real opportunity for growers to be part of a holistic management of their organic farm--developing, or at least trialing, varieties for their area," she said. "Growers are going to have a lot higher success rate the more they work with each other to provide feedback--what worked for you, what didn't, how do you set up a field trial--and exchange germplasm." For their part,
Seeds of Change, John Navazio's Seed Movement, and Abundant Life
seeds want to work with more growers to breed and produce seed for
organic agriculture. "We're always looking for people, said
Colley. "Especially as we expand into the bulk market, our
need for different types of growers in different areas and scales
of production is going to become more necessary."
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