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12/9/2016
1
Why and How to Save Seed: Wet 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 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, several palms, etc.)
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.
Classification
• Classification allows us to differentiate species to show relationships but also number organisms and take future inventories on natural life!
• Further within species are then ‘cultivars’ or ‘varieties’
• These cultivars are most important for seed saving and show distinct lines of each species (phenotypes)
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Limiting Insect Cross Pollination
• To breed true varieties we want to limit cross pollination, so members of the same crop or genus are isolated (or hand pollinated)
• This means growing a single variety of each crop in one location, or with large distance between them.
• If grew 5 basils in one bed then bees would spread pollen between all varieties and the subsequent seeds will not have the original traits of parents to breed true into the future• Will be a new combination of genes
Minimum Isolation Distances
• Lettuce = 20 ft
• Pepper/Tomato = 10‐20 ft
• Peas = 50 ft
• Beans = 100+ ft ideally, or 20 ft
• Corn = 1000‐2500 ft, to ½ mile• Light, wind adapted pollen
• Beets, Spinach, Brassicas = ½ mile or more• Wind adapted pollen and insect cross pollination
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Isolation Nets
• These may be placed over plants or flowers to allow for airflow but limit insect access to the plant
Hand Pollinating (Cucurbits)• Tie shut a male and female flower before they open
• Then remove the petals from a male flower (on left) and rub the stamen over each portion of the female flower
• Then seal the flower shut
• Then save seeds from the resulting melon/fruit
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Block Planting and Barrier Crops
• To save seed, it is beneficial to plant in blocks and not rows to limit pollen contamination• Then select seeds from the middle of the block
• Barrier crops are grown around the crop of interest for seed saving• These are densely planted, usually taller than crop plant, and with showy flowers• Add physical protection and distract pollinators• Sunflowers, amaranth, asters, etc.
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
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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 would harvest in the garden so seeds reach full size.
Cleaning and Storage
• At the end of this presentation will be a demonstration of how to clean seeds from wet sources like berries or fruits.
• The process is similar for a tomato, melon, etc.
• Seeds are dried then best stored in a cool, dark, and dry environment. • Paper envelopes or glass jars are superior to plastic bags
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Wildcrafting or Harvesting
• When harvesting berries or fruits from wild areas or public areas, it is important to never remove all fruits from a plant.
• Ethical seed saving would save at least half or more of the fruits/flowers on any wild plant!
• This ensures that it will survive in its habitat beyond your harvest
• Also, never harvest from a plant you do not know the identity of!!!
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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Hot Spots of Global Domestication
• klklk
Selection, Dedication and Time
Seed Savers Exchange has an estimated 20,000 varieties in its collection
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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.
Loss of Crop Varieties in 100 years
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Shown by…
Importance of Seed Saving
• To retain biodiverse and locally adapted crop varieties before they go extinct
• Returns autonomy to families and communities by allowing access to seeds
• 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!
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And to Have Options!
And because it is illegal…• Seed saving and exchanging through seed libraries could be considered technically illegal in many or most states.
• Because the seed lots are not put through rigorous testing like commercial seed providers, they could pose a risk to agriculture.
• 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!
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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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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.
Tomato Seed Saving
• Remove seeds and pulp from a selected tomato and place in a bit of water for several days until it become rotten on top
• Then the excess flesh and immature seeds will be poured off and the sunken seeds screened out
• Push seeds against the screen slightly to remove the jelly covering around the seed while rinsing
• Leave these to dry on a paper towel and ensure they are labeled with all important information
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Common Soil Lecture Series
• September: Why and How to Save Seed: Dry Seed Saving Ethics and Techniques (Asters)
• October: Prepping the Garden for the Winter, and Planting Perennial Seeds Outside
• 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
Online Resources
• Seed Savers Exchange –
http://www.seedsavers.org/learn
• Living Seed Library –
http://www.livingseedlibrary.net/seeds/seed‐saving/
• Seed Alliance –
http://seedalliance.org/uploads/publications/Seed_Saving_Guide.pdf
• And many more…