12/9/2016 1 Why and How to Save Seeds: Seed Saving Ethics and Techniques Andy Waltke, M.S. Creighton University Common Soil Seed Library Lecture Series Intro to Seeds • People have been collecting, growing and saving seeds for thousands of years. • Domesticated varieties of crops found in grocery stores today are massively different from the plants they were originally selected from. • Thus, each time you grow a pack of seeds you are adding to the continuum of plant breeding that has been ongoing for thousands of years.
Transcript
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Why and How to Save Seeds: Seed Saving Ethics and Techniques
Andy Waltke, M.S.
Creighton University
Common Soil Seed Library Lecture Series
Intro to Seeds
• People have been collecting, growing and saving seeds for thousands of years.
• Domesticated varieties of crops found in grocery stores today are massively different from the plants they were originally selected from.
• Thus, each time you grow a pack of seeds you are adding to the continuum of plant breeding that has been ongoing for thousands of years.
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Angiosperm Life Cycle
• Seed grows plant
• Plant flowers
• Fertilization occurs (pollen to stigma)
• Fruit and seeds develop in female flower parts• Ovules within the ovary
• Seeds dispersed to regrow again• Through eating fruits, wind, etc.
Flower Anatomy
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Flower Types
• Monoecious:• Perfect – has male and female parts in same flower
– Example: Tomato
• Imperfect – has male and female parts in different flowers but on same plant – Example: Many squashes
• Dioecious – different sexes of plants, one plant has only male flowers and another has only female flowers (kiwi, pawpaw, several palms, etc.)
Asteraceae
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Ray vs Disk Florets in Asteraceae
Pollination
• Cross Pollinating: pollen to another flower• By Wind: Grasses or Brassicas (beets, spinach)
• By Insect: Most vegetables and crops
• Self Pollinating: Happens before the flower opens (tomato)
• The critical step to achieve fertilization between pollen and receptive flower to ensure fruit production.
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Fruit Production From Fertilized Ovary
Open Pollinated vs Hybrid
• Seeds labeled as Open Pollinated simply mean that is occurred naturally without human intervention.
• OP plants will grow like their parents and are stable varieties
• Hybrid seeds are created through controlled crosses of different parent plants within the same species• Creates a new combination of characteristics that will grow out in first generation
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Hybridization
Hybrid Vigor
• Getting the “optimal” gene set from both parents
• Seen in selected hybrid seed for monoculture
• Also “naturally” evidenced by the Liger & Tigon.
Lion dad with
Tiger mom
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Phenotypes
• Phenotype is the expressed form in which the plant grows. It could be ‘tall’ or ‘short’ or any other set of characters.
• These are varieties of the same set of genes expressed in different ways.
• These show examples of tolerance to conditions or pests, or fruit size, or any number of traits.
• It shows the influence of the growing environment and produces unique characteristics among the same species.
Growing to Save Seed
• Limit insect cross pollination to breed true crops
• One cultivar per space if possible, and one member per genus is possible
• Separate them by at least 30‐50 ft typically
• In one garden, you may grow several types of different plants and save seed from them all.• Just not when five basil varieties are right next to one another for example
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What veggies do not need pollinators?• All leafy greens• Brassicas: broccoli, cauliflower, cabbage, etc.• Below ground root veggies and tubers:
beets, turnips, rutabagas• Most legumes including peas and beans• Corn• Many culinary herbs• Celery• Onions and leeks
Isolation Nets
• These may be placed over plants or flowers to allow for airflow but limit insect access to the plant
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Selection of Seeds• Mass Selection – plant an overabundance of one seed type, and select best individuals• Rouging = removing inferior plants before flowering
• Positive Selection – select for a certain trait and save seeds from that plant/fruit for next year• For best flavor, fruit size, plant shape, fruit storage, color of plant or fruit, timing of flowering…any number of characteristics
Crop Ancestors are Evidence of Selection
• Banana Tomato
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Corn Ancestor• Corn domestication occurred in modern day Mexico from teosinthe
• Selection for kernel size
• Selection for cob size
• Selection for plant size
• Etc.
Crop Diversity in One Species
• Plants of Brassica oleraceae have been selected for different plant parts in the past to now have hundreds of varieties of 6 major crops!
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Importance of Biodiversity• Natural resilience! Each variety has a story and different capacities.
• Massive human element in seed varieties with the amount of knowledge and care that went into their preservation over the long term!
• In the face of disease and climate change, old heirloom varieties hold the genetic richness to find traits like disease resistance or plants that grow well in a challenged environment like drought or heat.
Harvesting Fruit/Seeds
• For fleshy fruits, you want to select fruit from the height of the flowering period, and select overly ripe or grown fruits.
• This ensures the seeds reach maturity.
• Pick tomatoes when a bit soft after they were a firm fruit.
• Let cucumbers or squash get large beyond what you wouldharvest in the garden so seeds reach full
size.
• For flowers, cut off heads and let dry for many weeks
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Seed Saving from Wet Sources
• Remove or scrape seeds from fruit like in a tomato or watermelon.
• Rinse well with water and submerge for a few minutes. Any floating seeds are typically immature and not viable.
• For tomato, soak seeds in water for several days until it becomes rotten. Dump off the water and floating seeds/flesh. Then strain the seeds out and scape off the jelly covering. Let the seeds air dry several days.
Dry Seed Saving: How To
• Harvest seed pods and dry for many weeks • keep out of excessive heat and humidity
• Thresh – break it up the pods to free the seeds
• Sieve – use mesh screens to filter out seeds
• Winnow – let chaff and plant material blow away or separate from the seeds
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Seed Cleaning – Thresh/Sieve
• Use a pillowcase or thick trash bags
• Beat seeds out of pods
• Rub them
• Use sticks
• Walk on them
• Then use screens or colander to sieve out seeds
Seed Screens
• Order from Strictly Medicinal Seeds, Inc.
• Previously known as Horizon herbs
• Set of 8 seed screens for cleaning
• Or make your own!
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Winnowing Seeds• Use moving air to clean seeds
• Roll and fly – rolling seeds in a box and blow air against the direction of roll
• Pour seeds from container to container in front of a fan
Storing Seeds
• Humidity and temperature are bad
• Keep in manila/paper envelopes vs plastic bags
• Keep in glass jars instead of plastic bag
• Best in fridge for long term storage
• Best to use seeds quickly, if have excess donate them to the seed library!
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Importance of Seed Saving
• To retain biodiverse and locally adapted crop varieties before they go extinct (‘ecovars’)
• Returns autonomy to families and communities by allowing access to seeds for healthy foods
• Improves community relations and allows for social engagement
• Supports seed library and swap ventures so seeds produced by one may be accessed by many
• Its what we have always done as humans and becoming a lost skill!
Loss of Crop Varieties in 100 years
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Tallgrass Prairie• Estimates of 1‐4% of this ecosystem exists
• Only remains where it was too rocky to plow
• Fertile soils versus shortgrass prairie
• Coveted by the plow of pioneers
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Seed Libraries: Legal Seed Exchanges
• LB544 in Nebraska passed in 2015 to exempt seed libraries from commercial seed laws.• Only of its kind in the US and thanks to the hard work of Betsy Goodman of Common Soil Seed Library!
• Sept 2016 – California passes AB 1810
• Only Minnesota, Pennsylvania, Nebraska and now California have these protective laws.
Svalbard Seed Vault
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Ease of Seed Saving
• Easy = beans, lettuce, peas, pepper, tomato
• Intermediate = corn, cucumber, melons, squashes, and radish
• Difficult = onions, brassicas and apiaceae (carrot family)
• Easy plants will self pollinate and need less isolation distance but also have easy to process seeds.
• From there more distance is needed to keep purity in seed lines or more work to process some seeds.
Checklist for Seed Saving
• Identify crops or varieties you are interested in
• Find organic, open pollinated seed
• Create a journal and make notes on attributes and relevant dates• Record variety, planting date, flowering date, etc.
• Determine flower type and if need to hand pollinate or bag plant/flowers• What are considerations for that plant to save seed
• Is the plant an annual, biennial, perennial or what is its life cycle?
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Common Soil Lecture Series
• October: Prepping for the Winter, Planting Perennial Seeds, and Fungi in the Garden
• November: : Medicinal Plants, Herbs for Teas, Natural Dyes and other Garden Plant Uses. Intro to Research Resources
• Then…
• February 2017: Starting Seeds and Prepping the Garden
