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Seeds: The Future of Our Food

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1 Seeds: The Future of Our Food
Seeds are the first step in the food chain, upon which all life depends. It is important that we value seeds and work to protect this living heritage for our survival. Vocabulary highlighted in bold will be important for students to take note.

2 The Potato Famine ~1845-1850 Potato disease—late blight
Wide-spread hunger and disease Potato monocultures In Ireland, land was divided up so that rich families had optimal farm land—large plots with healthy soils. Poorer families were forced onto smaller, marginal pieces of land with poor, rocky soils. Because of this unequal land distribution, these poorer families had to rely on the potato as their main source of food, as potatoes grow well in poorer soils. The richer land was being used for grazing cows, whose meat feed the British demand. Take note that the good land was being exported, it was not feeding the countries own people. When the potato disease—late blight—arrived, it easily spread throughout these potato monocultures. Why do you think it spread so quickly? Monocultures are fields of the same crop—mono means one. How might this have been prevented? Had there been more diversity in these gardens and their diets, the disease of the potatoes would not have had such widespread consequences.

3 Corn Blight 1970 Fungus: Southern Corn Leaf Blight
Attacked the cytoplasm of the hybrid corn: T-cytoplasm 80% of U.S. corn in 1970 was this hybrid variety = 46 million acres Monocultures In summer of 1969, farmers in the mid-west began to notice that certain corn varieties were susceptible to the disease, one that they had never seen before. Ears of corn were rotting in their husks and stalks fell to the ground. Farmers didn’t pay much attention to it and figured that it was a fungus that would die off in the winter. However, in 1970, farmers in Florida began reporting a similar disease, and it was not long before it had spread to Mississippi, Alabama, Louisiana, and Texas. Carried by the wind, and accelerated by the unusually warm, moist weather of that summer, the disease began to wage a full-scale war with farms throughout the country, including the Corn Belt—Illinois, Indiana, and Iowa—where 85% of all U.S. corn is grown. Identified as "race T" of the fungus Helminthosporium maydis, it soon became known as the Southern Corn Leaf Blight. This fungus had the ability to take out an entire stand of corn in just 10 days. This blight was so serious and threatening, because corn is a major U.S. export, as well, corn supplies feed to domestic cattle, swine, and poultry. Additionally, corn is used in domestic food production. Therefore, the blight had far reaching consequences on the economy. The blight could also be transmitted in corn seed, and a year later, it was found in Japan, the Philippines, Africa, and Latin America. So how did this fungus have such devastating effects? This fungus was a mutation that specifically targeted the cytoplasm, or the watery material that surrounds the cell nucleus. At the time, plant breeders and seed companies had developed the “Texas male-sterile cytoplasm” or “T-cytoplasm”, named after a Texas variety of corn in which it was discovered. This T-cytoplasm was bred to be resistant to the most common corn diseases. This T-cytoplasm allowed breeders to crossbreed and pollinate large numbers of plants more easily, eliminating the time-consuming, labor-intensive, and economically expensive step of hand de-tasseling corn plants. This man-made change in corn plant was revolutionary in plant breeding, however, it was a change that was made without complete knowledge of the potential consequences. This variety did not have genes for resistance to a previously unimportant strain of a fungal disease; the southern corn leaf blight. At least 90% of the of hybrid corn planted in the U.S. contained this T-cytoplasm. The USA in 1970 had 46 million acres of corn with Texas male sterile cytoplasm. Had there not been such a monoculture, the fungus would not have been able to spread as rapidly, as it would have encountered barriers of genetically resistant plants—plants that are naturally adapted to fight different diseases and pests. for more information.

4 Heirloom vs. Hybrid HYBRID (F1) HEIRLOOM The result of artificially crossing two plants together Seeds do not produce “true to type” plants like the parents Bred for industrial traits. Reduce genetic diversity Open pollination Adapted to particular places Saved for their adaptive benefits Greater genetic diversity Often, these monocultures are planted with hybrid varieties, that are created by scientists and seed companies, as in the case of the Texas cytoplasm corn. Hybrid seeds are the result of artificially crossing two plants. If you save the seeds of these plant, they do not necessarily produce ‘true to type’, which means they will not necessarily come out like their parent plants. This is similar with people—just because your mother and father have blue eyes, they may have recessive genes from brown eyes, so you are not guaranteed to have blue eyes too. These hybrids are breed for reasons that appeal to industrial farms—mechanical handling, high yield, uniformity, and pest control. This genetic mixing reduces genetic diversity—recall in the game that diversity is important in order to respond to changes. The seeds must be purchased, because saving seed is not guaranteed, so farms across the U.S., and the world, begin using all the same varieties. There are fewer varieties available then, and these varieties will not necessarily thrive in all the different environments of this world. Heirloom seeds are open pollinated—which means they will grow “true to type” and produce plants like their parents from seed. They are adapted to a particular place and its climate, soil, growing conditions, and are often more resistant to the local pests and diseases. People save these seeds for this adaptability and for culinary and flavor preferences. Because heirlooms are adapted to a particular place, this reduces the need for using pesticides and herbicides, and other inputs, because the seeds will naturally do well here. Moreover, heirlooms increase the genetic diversity, because each seed changes and adapts to a particular place. What would heirloom seeds from Flagstaff be like? What qualities would they need to have to grow in this climate and place? –short growing season; can tolerate extreme temperatures between day and night; can do well at a high elevation

5 Examples of heirloom crops
Examples of heirloom crops. Notice the diversity of crops—color, shape, and if we could eat them they would have different flavors.

6 More examples… Moon and stars watermelon, bright lights swiss chard, zebra tomato. Again, notice the variety and diversity.

7 Values of Heirloom Crops
DIVERSITY TASTE ADAPTATION Gardens that use heirloom seeds value diversity (Of both crop species and genetic diversity), taste, adaptation to a particular place and its unique growing conditions (like this cactus is adapted to the desert), and the cultural traditions of the people planting the seeds (these seeds provide the ingredients for traditional dishes). CULTURE

8 Seed Saving One of the oldest traditions of civilization
Keeps alive traditional agricultural and culinary practices, essential for the stability of cultures Must be open pollinated Enhances biodiversity Throughout the history of agriculture, farmers have been breeding or selecting crops. Each farmer had a different taste preference and different needs for their individual farm and its soil, climate, and pests. As such, the seeds of a particular farm were unique to that place and person. Farmers often traded some seeds and bought some in times of shortage or to plant and experiment with new varieties, but most of the time they saved their own from the previous year's crop. This process resulted in an incredibly wide range of crop varieties in traditional agriculture. This age-old tradition is now being controlled by companies, where seed selection and breeding happens not on the farms, but in laboratories and university research centers. Because the hybrid varieties do not reproduce ‘true to type’ , farmers become dependent on buying new seed each year, instead of controlling their own fields and crops. This trend has consequently depleted the genetic diversity of crops, as many unique and adapted varieties are no longer being grown and saved. Instead, the only available seeds are those that the companies decide to market. Because GMO genes are patented it makes it illegal for farmers to save seed, or liable for lawsuits if GMO genes drift into their fields and plants . These patents and practices that discourage or even make it impossible for farmers to save seed infringes on their seed sovereignty. What do you think this phrase means? What does sovereignty mean? Seed sovereignty is the ability to grow, save, and pass on seeds within a community without outside influence.

9 Photos of seed saving practices—
covering flowers works to prevent bees and birds from cross pollinating; leaving beans to dry in order to collect seeds; drying ears of corn; scooping out tomato seeds and washing seeds.

10 GMOs Genetically Modified Organisms (GMOs) Biotechnologies
Genetic engineering / Gene transfer 1992: FlavrSavr Tomato Terminator genes Bt: New Leaf Potatoes GMOs are those plants, animals, and bacteria whose genetic makeup has been altered by way of a special set of technologies. These technologies, termed ‘biotechnologies’, combine the genes of one organism into another for the reason of highlighting a particular trait. Gene transfer or genetic engineering is the process of taking a selected gene from one organism and inserting it into another. Unlike traditional forms of crop breeding, genetic engineering allows the transfer of genes across species and even kingdom boundaries. In 1992, Calgene developed FlavrSavr, the first commercially GMO food to be granted a license for human consumption. The FlavrSavr was not required to be labeled GMO. While the tomato did poorly, and was off the market by 1997, the tomato drastically changed the direction of GMOs Terminator genes implanted in genetic code make for sterile seeds after one generation. Farmers are unable to save seeds for the next season. New Leaf Potatoes were developed by Monsanto, a major agricultural company that makes pesticides, fertilizers, and GMOs. Potato leafs are introduced with genes from soil bacterium Bt, found naturally in the soil. When the common pest, Colorado Potato Beetle, eats the leaves, it eats this natural bacterium and dies. Potatoes not managed by FDA, because they are considered by the government to be pesticides. Another example of GMOs include tomatoes that have been crossed with fish genes. Scientists have created this frost-resistant tomato by adding an antifreeze gene from a cold-water flounder fish.

11 GMO crops—you cannot really notice any remarkable difference, these crops look healthy. You can notice the uniformity of these crops—they are perfect in appearance, which is something that scientists try to breed—a uniformity to attract the customer at the grocery store.

12 Values Efficiency Industrialization Output Uniformity
Instead of valuing diversity, taste, adaptation, and culture, as heirloom seeds do, these GMOs represent the values of industrial agriculture, including monocultures, efficiency, industrialization and technology, high output, and uniformity.

13 GMOs around US and the World
GMOs are now grown in 42 countries on 6 continents Currently, over 1 billion acres of land contain GMO crops. 2/3 of this acreage is in USA. 70% of products on grocery shelves in USA contain GMO ingredients “Fun” facts about GMOs

14 GMO Crops Soybeans Corn Cotton Tomatoes Potatoes Rapeseed (Canola Oil)
Sugar cane Sweet Corn Rice This graph shows an increased use of GMO crops in U.S. farms. Notice almost 90% of all soybeans planted are GMO, and about 40% of all corn planted is GMO. The trend of using this crops is increasing. This is a list of the most genetically modified crops throughout the world.

15 The Potential Risks of GMOs to People and Environment
PROS CONS Reduced pesticide use initially Convenient Short term resistance initially Initial higher yield Unknown risks to human health and environment Long term resistance Cross pollination with non-GMOs Loss of biodiversity Ethical considerations Loss of ability to save seed What do you think are some of the Pros and Cons of using GMOS? Brainstorm these on the board first as a class… they see how the class list compares. Pros: Reduce pesticide use: Not necessary true, as an overwhelming number of GMO crops require the use of heavy chemicals such as the widely used Round-Up Ready line of crops produced by Monsanto. The company not only benefits from the seed profit, but from the world’s most widely used herbicide Round-Up manufactured by Monsanto. Convenience: Farmers do not have to save seeds or decide among a wide variety of herbicides. With Bt crops farmers do not have to monitor pest levels and decide if and when to apply pesticides, and they don't have to spray as often. The pesticide is automatically produced by the plant. Resistance: Several weeds have begun to develop resistance to the types of herbicides commonly used. However, little is know about this GMO technology, so resistance could still develop. Cons: Unknown Risks: GMOs are such a new technology, that it is impossible to know the longer term affects to human health and the environment. It took us a long time to know the harm of tobacco, pesticides, and heavy metals. GMO foods do not have to be labeled in the US, so it is hard to track and study the long term health effects of these products. What happens if a plant is crossed with a peanut and someone with a nut allergy eats this plant? Long term resistance: While in the short term, pests may not be able to compete with this crops, in the long term, nature develops resistance to these measures, and thus we are left with “super pests” and “super weeds” that can withstand these assaults of GMOs and pesticides. Cross pollination: Genes can ‘escape’ and find there way into species. What would happen if the herbicide-resistant genes found their way into weeds? This cross pollination is a serious threat to biodiversity, as we are introducing genes into the environment without knowing the full effects. Loss of Biodiversity: GM crops could compete or breed with wild species threatening biodiversity. What happens to the birds, insects, and other wildlife that come in contact with and eat these GMOs? Ethical Consideration: Intrinsic values of nature are not considered when we, humans, take control and modify species. Seed Saving: An age-old tradition that maintains farmers self sufficiency and independence is threatened when they become dependent on seed companies. STOP SLIDE SHOW HERE. WILL SHOW LAST SLIDE DURING DISCUSSION.

16 CSAs and Farmers Markets
Alternatives to GMOs Seeds of Trust Native Seed/SEARCH Community Seed Banks Seed Exchanges CSAs and Farmers Markets Community Gardens GMO labeling Seeds of Trust, based in Cornville, AZ, a seed company specializing in heirloom, high altitude varieties, and seed saving lessons. Native Seed/SEARCH, based in southern AZ, a seed company specializing in heirloom, native crop varieties. Community seed banks and seed exchanges lets gardeners exchange seeds that are grown and adapted to that place’s particular climate and culture. Reduces dependency on large seed companies CSAs and Farmers Markets—buy crops that are from local farmers, who use native and heirloom varieties Community gardens—grow plants adapted to your place and share the seeds! GMO labeling—It is in debate right now whether or not products should be labeled if GMOs are used. All of the European Union nations, Japan, China, Australia, New Zealand and many other countries require the mandatory labeling of foods that contain genetically engineered ingredients. If the US required labeling, perhaps people would not purchase this food, and simple supply and demand would force farmers to change their seeds.

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