saving seeds for a food-secure future

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Saving Seeds for a Food-Secure Future Heidi Kratsch Area Horticulture Specialist

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Page 1: Saving Seeds for a Food-Secure Future

Saving Seeds for a Food-Secure FutureHeidi KratschArea Horticulture Specialist

Page 2: Saving Seeds for a Food-Secure Future

What is a Seed?

OProduct of sexual reproduction

OMaximizes genetic diversity

Page 3: Saving Seeds for a Food-Secure Future

Genetic diversity is decreasing

O95% of human food needs now provided by just 4 crops: rice, wheat, corn, potatoes.

OIndustrial agriculture focuses on only a handful of cultivars.

O75% of agricultural genetic diversity disappeared in the last century.

Page 4: Saving Seeds for a Food-Secure Future
Page 5: Saving Seeds for a Food-Secure Future

Wheat Stem Rust (Ug99)

OFirst identified in Uganda in 1999.

OHas spread through Africa into the Middle East.

O~90% of world’s wheat is defenseless against this virulent strain.

Puccinia graminis

Page 6: Saving Seeds for a Food-Secure Future

The Irish Potato Famine

Page 7: Saving Seeds for a Food-Secure Future

Panama DiseaseO1950s – ‘Gros

Michel’ – wiped out!

OToday – ‘Cavendish’- it’s dying!

OFuture – do we need a new cultivar?

Page 8: Saving Seeds for a Food-Secure Future

The Corn Monoculture

Page 9: Saving Seeds for a Food-Secure Future

Bringing back biodiversity

Page 10: Saving Seeds for a Food-Secure Future

Diversity is nature’s survival

wild card.

Plant and Save

Seeds!

Page 11: Saving Seeds for a Food-Secure Future

Step 1: Avoid growing F1 hybrids

OAlmost all corn seed

OMany varieties of cross-pollinated species

OMust buy new seeds every year

Page 12: Saving Seeds for a Food-Secure Future

Choose open-pollinatedOCome true to typeOThe easiest are self-

pollinated: beans, peas, tomatoes, peppers

OHeirloom varieties – saved through generations of families and neighbors

OHistory goes back 12,000 years!

Page 13: Saving Seeds for a Food-Secure Future

Step 2: Protect varietal purity

Page 14: Saving Seeds for a Food-Secure Future

Flower Structure

Page 15: Saving Seeds for a Food-Secure Future

Definition of Terms

OAnnual, biennial, perennialOPerfect flowerOImperfect flowersOVernalizationOMonoecious (single house)

plantsODioecious (two houses)

plants

Page 16: Saving Seeds for a Food-Secure Future

Self-Pollination

Page 17: Saving Seeds for a Food-Secure Future

Bagging self-pollinators

Bagging flowers on pepper plants

Page 18: Saving Seeds for a Food-Secure Future

Plants self-pollinate in the bag

Reemay bagsTreated paper bags

Page 19: Saving Seeds for a Food-Secure Future

Cross-Pollination

Page 20: Saving Seeds for a Food-Secure Future

Cross-pollination by insects

OCucurbitsOBrassicasOUmbelliferae

Page 21: Saving Seeds for a Food-Secure Future

Cross-pollination by wind

OCornOSpinachOBeetsOChard

Page 22: Saving Seeds for a Food-Secure Future

Isolate plants that readily cross-pollinate

ODistanceOTimeOBaggingOCaging

Page 23: Saving Seeds for a Food-Secure Future

Pollination Cages

OFrame:OWoodOWireOPlastic pipe OMetal tubing

OCovered with:OSpun

polyester cloth (Reemay)

OWindow screen

Page 24: Saving Seeds for a Food-Secure Future

Alternate Day CagingONeed a

minimum of two cages.

OAlternate days open to pollinators.

Kale and cabbage will readily cross pollinate.

Page 25: Saving Seeds for a Food-Secure Future

Caging with

pollinators

Page 26: Saving Seeds for a Food-Secure Future

1

4

2

3

Page 27: Saving Seeds for a Food-Secure Future

Step 3: Rogue plants for trueness to type

Page 28: Saving Seeds for a Food-Secure Future

Select desirable characteristics

OVigorOEarlinessODrought

resistanceOInsect resistanceOFlavorOLate bolting in

cool-season crops

Page 29: Saving Seeds for a Food-Secure Future

Ample population sizeOEspecially

important for cross-pollinating plants.

OSelect a minimum of 6 plants for seed saving.

OMore plants = more genetic diversity

Page 30: Saving Seeds for a Food-Secure Future

Questions?

Page 31: Saving Seeds for a Food-Secure Future

Step 4: Harvest Seeds

Page 32: Saving Seeds for a Food-Secure Future

Overwintering Biennials

OSeed-to-seed method

vs.OSeed-to-root-to-

seed method

OBiennials include:O Carrot, celery,

parsleyO Beet, chardO Leek, onionO Rutabaga, turnip,

parsnipO Broccoli, kale,

brussels sprouts

Page 33: Saving Seeds for a Food-Secure Future

Root Cellarin

g

Page 34: Saving Seeds for a Food-Secure Future

Onions (Allium cepa) Cepa group

OBiennial, cross-pollinating (insect)

OOverwinter in ground or lift bulbs.

OBulbs – harvest seed first season

OSeed – harvest seed second season.

Don’t wait too long to harvest seed or the seed heads will shatter!

Page 35: Saving Seeds for a Food-Secure Future

Broccoli (Brassica oleracea)

OBiennial, cross-pollinating (insect)

OWill cross with all other plants of this species.

ODo not eat plants grown for seed.

OUse cold frame, small hoop house to overwinter.

Page 36: Saving Seeds for a Food-Secure Future

Beets and Chards (Beta vulgaris)

Biennial, cross-pollinated (wind) – bag or cage

Up to 4 feet tall!

Page 37: Saving Seeds for a Food-Secure Future

Spinach (Spinacia oleracea)Male plant with flowers

Female plant with seeds

Dioecious, annual, cross-pollinating (wind)

Page 38: Saving Seeds for a Food-Secure Future

Lettuce (Lactuca sativa)

OSelf-pollinating annual

OBolts in response to lengthening days

OHead-lettuce types need to be slit to allow seed stalk to emerge.

O Seeds ripen 12-24 days after flowering

Page 39: Saving Seeds for a Food-Secure Future

Squash (Cucurbita pepo)Acorn, yellow crookneck, scallop, zucchini

OMonoecious, cross-pollinating (insect) annual

OCut fruit from vine and let sit for 3 weeks or longer before harvesting seed. Male flower Female flower

Page 40: Saving Seeds for a Food-Secure Future

Pea (Pisum sativum)OSelf-pollinating

annualOAllow pods to dry

on the vine.OFreeze pods in

airtight container for 3-5 days to kill weevil eggs. Peas and beans are easy

for beginning seed savers.

Page 41: Saving Seeds for a Food-Secure Future

Carrot (Daucus carota)OBiennial, cross-

pollinated (insect)OUse seed-to-root-

to-seed method OUmbels can be

left to dry on the plant, or

OCut and air-dry.ODe-bearding is

unnecessary.

Page 42: Saving Seeds for a Food-Secure Future

Corn (Zea mays)OCross-pollinated

(wind) annualOTassels vs. silksOGrow in blocksOSusceptible to

inbreeding depression

ODry ears on the stalk, or remove and dry under shelter

Page 43: Saving Seeds for a Food-Secure Future

Step 5: Clean seeds

ODry processing

OWet processingOFermentingORinsingODecanting

Page 44: Saving Seeds for a Food-Secure Future

Dry processing – threshing, winnowing

Page 45: Saving Seeds for a Food-Secure Future

Wet processing

ORemove seeds from fruit

OWash and rinse

OAir-dryOFerment –

tomato, cucumber

Tomato seeds must be fermented to remove gelatinous coating.

Page 46: Saving Seeds for a Food-Secure Future

Fermentation

Page 47: Saving Seeds for a Food-Secure Future

Step 6: Store seeds

OExcellent storage produces vigorous seeds.

OTwo enemies:OHigh

temperatureOHigh moisture

Page 48: Saving Seeds for a Food-Secure Future

Long-term storage

OCool, dry conditions

OEnvelopesOMoisture-proof

container or freezerOMust be “very

dry.”

Page 49: Saving Seeds for a Food-Secure Future

Getting to “very dry”

OFan/air conditioner

OFood dehydrator

OSilica gelOCheck daily

until between 5-7% moisture

Page 50: Saving Seeds for a Food-Secure Future

Testing for Dryness

OWeigh before and after drying slowly in an oven at low temperature.

OSeed moisture content (%) = fresh seed weight – dry seed weight ÷ dry seed weight × 100%

Page 51: Saving Seeds for a Food-Secure Future

Long-term storage

OFrozen seeds last up to 10 times longer

OStore in paper envelopes with silica gel “dessicant” for one week.

OAllow frozen sealed jar to reach room temp before opening

Supplies:OSeed Savers

Exchange – www.seedsavers.org

Page 52: Saving Seeds for a Food-Secure Future

Keep good recordsOKeep a card for

each variety.O Plant and varietyO Source, date

obtainedO Germination %O Date storedO Accession numberO Last year grown

Page 53: Saving Seeds for a Food-Secure Future

Veggies generally not grown from seed

OPotatoOGarlicOArtichokeOAsparagusOSweet potatoORhubarb

Page 54: Saving Seeds for a Food-Secure Future

Questions?