REPRODUCING PLANTS

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REPRODUCING PLANTS

• CHAPTER 8
• AGRISCIENCE AND TECHNOLOGY

Modified by Georgia Agricultural Education
Curriculum Office
July, 2002
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TYPES OF PLANT REPRODUCTION

• SEXUAL REPRODUCTION - Involves using seed to
  propagate plants. Flowers are important because
  they contain the reproductive organs.
• ASEXUAL REPRODUCTION - Involves reproducing
  plants by using vegetative parts of the plant.
  Results in clones (genetically like their
  parents).

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KINDS OF SEED

• MONOCOT - Plants having seed with one seed leaf,
  known as a cotyledon. Examples are corn, wheat,
  rice and all grasses.
• DICOT - Plants that have seed with two cotyledon.
  Examples are tomatoes, beans, petunias and
  carnations.

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PARTS OF A BEAN SEED

• EXTERNAL
• Seed coat - Outer covering of the seed
• Hilum - Where the seed was attached in the pod.
• Micropyle - Tiny opening near the seed scar where
  the pollen entered the ovule to form the seed.

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PARTS OF A BEAN SEED

• INTERNAL
• Cotyledons - Bean seed has two contain food for
  the embro.
• Radicle - Becomes the root system of the plant.
• Hypocotyl - Connects the radicle and the
  cotyledons.
• Epicotyl - Forms the stem of the plant.
• Plumule - Develops the above-ground part of the
  plant (embryonic leaves).

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PARTS OF A MONOCOT SEED CORN

• EXTERNAL
• Seed coat - Protects the embryo.
• Seed scar - Where the corn grain was attached to
  the cob.
• Silk scar - Opposite side of the grain from the
  seed scar.

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PARTS OF A MONOCOT SEED CORN

• INTERNAL
• Endosperm - Where the food is stored for the
  embyo.
• Radicle - Becomes the root system.
• Hypocotyl - Connects the radicle with the food
  source.
• Epicotyl - Forms the stem.
• Cotyledon - Does not store food absorbs food
  from the endosperm.
• Plumule - Develops into leaves.

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PARTS OF A COMPLETE FLOWER

• Sepals - Outer part of the flower covers the bud
  and protects it as it develops.
• Petals - Located just inside the sepals attract
  insects which help with the fertilization
  process.
• Stamens - Male part of the flower contains an
  anther that produces pollen, or sperm.
• Pistil - Female part of the flower contains the
  stigma

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FLOWERS

• PERFECT FLOWERS - Contain the stamen and pistil
  in the same flower.
• IMPERFECT FLOWERS - Flowers that lack either the
  stamen or pistil.
• Exception Monoecious plants may have both male
  and female imperfect flowers on them. Corn is an
  example.

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POLLINATION

• Transfer of pollen from an anther to a stigma of
  a flower of the same species.
• Pollen may be moved by wind, insects, birds and
  other natural means.
• Cross-pollination - When two different plants are
  involved.
• Self-pollination - Involves flowers on the same
  plant.

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TYPES OF FRUIT

• FLESHY FRUIT - Have large fibrous structures
  surrounding the seed apples, pears,
  blackberries, oranges and grapes are examples.
• DRY FRUIT - Fruit develops as a pod or in a hull
  beans, peas, peanuts and cotton are examples of
  dry fruit. Pecans, acorns, corn, oats, wheat, elm
  trees are examples of hulls.

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GERMINATION TESTING

• When a number of seeds sprout out of a set amount
  is called a germination test.
• Helps in determining the number of seeds to
  plant.
• Soil is the most widely growing medium however
  greenhouses usually use artificial media.

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CONDITIONS FOR SEED GERMINATION

• MUST HAVE THE FOLLOWING
• MOISTURE
• TEMPERATURE
• OXYGEN

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BENEFITS OF VEGETATIVE PROPAGATION

• True traits of parents - Assures that the new
  plant is identical to its parents.
• No seed - Some plants do not produce seed an
  example is seedless grapes.

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EXAMPLES OF VEGETATIVE PROPAGATION USING BELOW
GROUND PARTS

• Potatoes are cut into sections with buds (eyes)
  and planted.
• Bulbs or corms are planted multiply and new
  bulbs are pulled apart and planted separately.

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METHODS OF ABOVE GROUND PROPAGATION

• LAYERING - Involves getting roots to grow from
  the stems of plants
• CUTTING - Involves using a short section of plant
  stem for propagation.
• BUDDING - Involves taking a bud from one plant
  and moving it to another.
• GRAFTING - Involves placing a section of the stem
  of one plant onto another plant.

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QUALITIES OF GOOD SEED

• Purity - Contains only seed intended.
• Contamination - Free of trash
• Percent germination - Should be 90-100
• Uniformity - Same size and shape
• Damage - Seed coats should not be cracked
• Free of disease - Healthy
• Treatment - Treated to prevent disease
• Reputation of grower and dealer