Our Blog

Seeds of Truth

February 2015

Seed Basics

  • A Seed is a single cell
  • Monocotyledon vs. Dicotyledon
  • Monocot – single cotyledon (baby) leaf – “grasses”
    • grass, banana, palm tree, corn, etc.
    • new growth from center of plant
    • plant doesn’t get thicker with age
  • Dicot – double cotyledon (baby) leaves – “plants”
    • all other plants
    • new growth at ends and outside of plant
    • plant gets taller and thicker over time

 

Seed Dissection

  • remove the protective coating
  • find the cotyledon leaves
  • find the root growth tip

 

Seed Dispersal Mechanisms

  • How a seed chooses to spread itself. All plants want to spread and use different mechanisms for distribution
  • Exploding seed pod
    • Seeds grow in pod that “blows up” spreading seeds around plant
    • beans, peas, legumes, california poppies, many wildflowers
  • Parachute Seeds
    • seeds come with individual parachute that spreads seed by wind
    • dandelion, chicory, thistles, artichoke
  • Stickers
    • Seeds come with spines that attach to animal fur
    • carrots, celery, other carrot family plants
  • Fruits
    • Seed is surrounded by fleshy, good tasting fruit that encourages animals to eat seeds and spread them through poop
  • Bird Seed
    • Seed itself is tasty, providing nutrition to animals and birds. Undigested seed sprouts from poop
    • Sunflower, millet, wheat, sesame
  • Human
    • Seed produces a plant with characteristics desired by humans. Humans spread the plant through travel and trade
    • all domesticated plants

 

Seed Coatings & Scarification

  • Seed coatings are often designed to withstand a specific “scarification” process, which breaks down the seed coating and allows the seed to germinate
  • Examples:
    • sunflower seed coatings are designed to withstand a birds digestive system, and germinate BETTER after being digested
    • large, heavy seeds often need to ROLL down a hill, being scratched by soil on the way down, before germination is possible
    • redwood tree seeds REQUIRE exposure to smoke to become scarified. They are designed to germinate after a fire.

 

Seeds and life – CoEvolution

  • Seeds are constantly evolving, developing new ways to spread themselves
  • The Sloth and the Avocado
  • Humans are the plants we farm have Co-Evolved, we are dependent on one another

 

Conventional Seed Breeding

  • Humans have been breeding seeds since the beginning of agriculture
  • Breeding refers to the act of saving seeds from plants which exhibit wanted characteristics and removing plants with unwanted characteristics
  • Seeds that can no longer survive in the wild without human intervention are known as “domesticated”
  • First domesticated plants: wheat, barley, rye, rice, gourds
  • Process of breeding:
    • Plant seeds
    • Select plants with wanted characteristics: height, strength, disease resistance, seed size, fruit size, etc.
    • Save seeds from these plants. Eat or otherwise remove seeds from plants with unwanted charcteristics
    • Plant saved seeds. Again further select for wanted characteristics..
    • Repeat process until seeds reliably produce seeds with wanted characteristics
  • Seed breeding is always a process of trade-offs
    • “whatever you don’t breed for is lost”
    • breed only for sweetness, and disease resistance will be lost
    • breed only for color, and flavor/nutrition will be lost
    • breed only for transportability, and color/taste will be lost

 

Types of Seeds

 

  • Wild Open Pollinated Seed

 

      • Large genetic diversity to be able to survive in large variety of conditions and withstand rapid changes in growing conditions
      • Seeds do not produce plants similar to parents
      • Each seed has a wide variation in characteristics: height, vigor, disease-resistance, heat-tolerance, salt-tolerance, wind-tolerance, etc.
      • Strong seed dispersal method

 

  • Domesticated Heirloom/Open Pollinated Seeds

 

      • Technical definition for Heirloom is simply a open-pollinated seed that has been grown since before WWII. Heirloom and Open-Pollinated are often used interchangeably
      • Open Pollinated seeds reliably produce seeds with similar characteristics when pollinated with same variety of seed
        • Example 1. Pollinate Black Krim Tomato with Black Krim Tomato and you get Black Krim Tomato
        • Example 2. Two French people have kids, their kids will have characteristics of French people
      • Open Pollinated seeds are “in-bred”. They lack the genetic diversity of their wild relatives because they have been bred to have a limited set of characteristics

 

  • Hybrid Seeds

 

      • Hybrids are the result of the cross pollination between two distinct “open-pollinated” in-bred lines.
        • Example 1. Cross Pollinating an Oxheart Tomato with a Yellow Pear Tomato
        • Example 2. A French person and Chinese person have a kid
      • For unknown reasons, many hybrid plants express “hybrid vigor” – extreme vigorousness, productivity and health
      • Can  you save hybrid seeds?
        • Yes, BUT most children of hybrid plants will not be similar to parent plants
        • Example 1: 100 French-Chinese couples have children. All of these children will reliably have similar characteristics – they will all be 50% and 50% Chinese(known as F1 hybrids in plant breeding). However, if these 100 children were to have kids, the 2nd generation children would all look different: some would be mostly French, some would be mostly Chinese, and some would look mixed like the 1st generation.
      • Open Pollinated Seeds can be created from hybrids after many generations of breeding:
        • Example: Sun Gold cherry tomatoes are hybrids that are very sweet, and the plants are vigorous. Save 100 seeds each from 100 sun gold plants and plant them all out; this first generation would mostly be very different from the original Sun Gold, but some plants would be similar to Sun Gold. Save the seeds from plants similar to the original Sun Gold. Plant those seeds out, and again select seeds from plants similar to Sun Gold. Repeat this process for several generations, until your seeds all produce plants similar to Sun Gold. These seeds would be Open Pollinated Sun Gold Tomatoes.

 

  • GMOs

 

    • A departure from natural selection techniques
    • Genes are manipulated on an individual level, and genes can be moved across species barriers through modern biotechnology
    • How GMO’s are developed?
      • Wanted genes (along with a “marker” gene) are isolated and forcibly inserted into DNA of plant tissue either using a gene gun or virus in an imprecise way
      • Most tissue will die off because gene was inserted into a bad position, scrambling the plants DNA
      • A few plants will survive and plant tissues are then multiplied through tissue culture to reach a mature state
      • Resulting plants are tested for characteristic of inserted gene, and then bred to produce a commercially viable seed
    • GM plants can be bred with non-GM plants and retain the GM characteristics
    • New GM techniques are more precise. Scientists can now target where they want to insert new genes. This has greatly increased the speed at which GM crops can be developed.
    • GMOs are also being developed to produce sterile seed, to prevent farmers from being able to save seed

 

The Good, the Bad, and the Ugly

 

  • Open Pollinated Seeds

 

      • Most seeds we use to grow today were selected and adapted for different climates and soils
      • Very few seeds have been adapted or developed specifically for LA’s growing conditions
      • These seeds have been eaten historically, and were developed for flavor, nutrition, beauty, and other valuable characteristics
      • OP seeds cannot be patented or owned, yet

 

  • Hybrid Seeds

 

      • Seeds have been developed for commercial viability: transportation, color, appearance, rather than characteristics we desire in food
      • Seeds can be protected by Copyright and method of developing seed held secret
      • Most fruit trees are hybrids
      • NOT necessarily bad or unwanted. Hybrid seeds CAN be developed with desirable characteristics
      • Seed production cannot be done at a home scale

 

  • GMOs

 

      • Health effects unknown
      • ecological effects known
      • Possibility for Genetic Pollution
      • Corporate control of seed, Full Seed Patenting allowed
      • No actual benefits seen yet

 

  • Our Approach – WILD SEED

 

    • Open Pollinated seeds are great, but their genetic diversity has already been limited by years of breeding in different growing conditions
    • Seeds need to be “re-wilded” and then new varieties can be selected for from a genetically diverse seed set
    • How to achieve?
      • Grow many different varieties of the plants you want to grow
      • Allow those varieties to cross-pollinate (or even manually cross-pollinate) and then save seeds
      • Interbreed plants for multiple generations, until genetic diversity is achieved
      • Leaves seeds in this “wild” state OR
      • Select for locally adapted and developed varieties from these wild seeds