Grow Your Own, Nevada! Fall 2012: Saving Seeds from Your GardenPresentation Transcript
Saving Seeds for aFood-Secure FutureHeidi KratschArea Horticulture Specialist
What is a Seed?O Product of sexual reproductionO Maximizes genetic diversity
Genetic diversity is decreasing O 95% of human food needs now provided by just 4 crops: rice, wheat, corn, potatoes. O Industrial agriculture focuses on only a handful of cultivars. O 75% of agricultural genetic diversity disappeared in the last century.
Wheat Stem Rust (Ug99)O First identified in Uganda in 1999.O Has spread through Africa into the Middle East.O ~90% of world‟s wheat is defenseless against this virulent Puccinia graminis strain.
The Irish Potato Famine
Panama Disease O 1950s – „Gros Michel‟ – wiped out! O Today – „Cavendish‟- it‟s dying! O Future – do we need a new cultivar?
The Corn Monoculture
Bringing back biodiversity
Step 1: Avoid growing F1 hybridsO Almost all corn seedO Many varieties of cross-pollinated speciesO Must buy new seeds every year
Choose open-pollinatedO Come true to typeO The easiest are self-pollinated: beans, peas, tomatoes, pepper sO Heirloom varieties – saved through generations of families and neighborsO History goes back 12,000 years!
Bagging self-pollinators Bagging flowers on pepper plants
Plants self-pollinate in the bag Treated paper bags Reemay bags
Cross-pollination by insects O Cucurbits O Brassicas O Umbelliferae
Cross-pollination by windO CornO SpinachO BeetsO Chard
Isolate plants that readily cross-pollinateO DistanceO TimeO BaggingO Caging
Pollination CagesO Frame: O Covered with: O Wood O Spun O Wire polyester cloth O Plastic pipe (Reemay) O Window O Metal tubing screen
Alternate Day CagingO Need a minimum of two cages.O Alternate days open to pollinators. Kale and cabbage will readily cross pollinate.
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Step 3: Rogue plants for trueness to type
Select desirable characteristicsO VigorO EarlinessO Drought resistanceO Insect resistanceO FlavorO Late bolting in cool-season crops
Ample population sizeO Especially important for cross-pollinating plants.O Select a minimum of 6 plants for seed saving.O More plants = more genetic diversity
Step 4: Harvest Seeds
Overwintering BiennialsO Biennials include: O Carrot, celery, pars O Seed-to-seed method ley vs. O Beet, chard O Leek, onion O Seed-to-root-to-seed O Rutabaga, turnip, p method arsnip O Broccoli, kale, brus sels sprouts
Onions (Allium cepa) Cepa groupO Biennial, cross- pollinating (insect)O Overwinter in ground or lift bulbs.O Bulbs – harvest seed first seasonO Seed – harvest Don‟t wait too long to seed second harvest seed or the seed season. heads will shatter!
Broccoli (Brassica oleracea)O Biennial, cross- pollinating (insect)O Will cross with all other plants of this species.O Do not eat plants grown for seed.O Use cold frame, small hoop house to overwinter.
Beets and Chards (Beta vulgaris) Up to 4 feet tall!Biennial, cross-pollinated (wind) – bag or cage
Spinach (Spinacia oleracea) Male plant with flowers Female plant with seedsDioecious, annual, cross-pollinating (wind)
Lettuce (Lactuca sativa)O Self-pollinating O Seeds ripen 12-24 days after flowering annualO Bolts in response to lengthening daysO Head-lettuce types need to be slit to allow seed stalk to emerge.
Squash (Cucurbita pepo) Acorn, yellow crookneck, scallop, zucchiniO Monoecious, cross- pollinating (insect) annualO Cut fruit from vine and let sit for 3 weeks or longer before harvesting Male flower Female flower seed.
Pea (Pisum sativum)O Self-pollinating annualO Allow pods to dry on the vine.O Freeze pods in airtight container for 3-5 days to kill Peas and beans are easy for weevil eggs. beginning seed savers.
Carrot (Daucus carota)O Biennial, cross- pollinated (insect)O Use seed-to-root-to- seed methodO Umbels can be left to dry on the plant, orO Cut and air-dry.O De-bearding is unnecessary.
Corn (Zea mays)O Cross-pollinated (wind) annualO Tassels vs. silksO Grow in blocksO Susceptible to inbreeding depressionO Dry ears on the stalk, or remove and dry under shelter
Step 5: Clean seedsO Dry processingO Wet processing O Fermenting O Rinsing O Decanting
Dry processing –threshing, winnowing
Wet processingO Remove seeds from fruitO Wash and rinseO Air-dryO Ferment – tomato, cucumTomato seeds must be fermented to remove gelatinous ber coating.
Step 6: Store seedsO Excellent storage produces vigorous seeds.O Two enemies: O High temperature O High moisture
Long-term storageO Cool, dry conditionsO EnvelopesO Moisture-proof container or freezer O Must be “very dry.”
Getting to “very dry”O Fan/air conditionerO Food dehydratorO Silica gelO Check daily until between 5-7% moisture
Testing for DrynessO Weigh before and after drying slowly in an oven at low temperature.O Seed moisture content (%) = fresh seed weight – dry seed weight ÷ dry seed weight × 100%
Long-term storageO Frozen seeds last Supplies: up to 10 times O Seed Savers longer Exchange –O Store in paper www.seedsavers.org envelopes with silica gel “dessicant” for one week.O Allow frozen sealed jar to reach room
Keep good records O Keep a card for each variety. O Plant and variety O Source, date obtained O Germination % O Date stored O Accession number O Last year grown
Veggies generally not grown from seedO PotatoO GarlicO ArtichokeO AsparagusO Sweet potatoO Rhubarb