Hydroponic Agriculture

1
Hydroponic Agriculture

• Controlled Environment Agriculture

2
Hydroponics

• Hydroponic farming is a method of growing plants
  in water instead of soil.
• Why Hydroponics?
• Toxic Soil
• Nutrient Poor Soils
• Greater Yield
• Scientific Applications
• Used to test how different nutrients affect a
  plant.
• Better control of nutrient feeding.

3
Germination

• When a seed starts to grow, we say it germinates.
  
• The cotyledons store food for the baby plant
  inside the seed.
• When the seed starts to germinate, the first
  thing to come out is the main root.
• The skin starts to split and the tiny shoot
  straightens, carrying the cotyledons with it.
• To grow, the seed's growing conditions usually
  have to be damp, warm, and dark.
• A dry seed will stay dormant unless it soaks in
  some water. Then it will start to germinate.

4
(No Transcript)
5
Plant Nutrition

• The method of nutrition common in plants, some
  bacteria, and all algae is called ____________.
• photosynthesis
• These organisms are called ____________.
• autotrophs
• The raw materials ______________combine with
  sunlight to produce glucose a.k.a simple sugar.
• carbon dioxide water
• The glucose made is used as an ______ ______
• energy source
• Most ________in the air results from
  photosynthesis.
• oxygen

6
The Chemistry of Photosynthesis

• Photosynthetic Pigments are needed to trap
  light energy.
• Chlorophyll a
• Beta-carotene (function not understood)
• Chemical Equation for Photosynthesis
• CO2 H2O light energy chlorophyll a C6H12O6
  H2O O2
• Light energy absorbed by the Chlorophyll a is
  converted to _______ __________.
• chemical energy (ATP).
• Photosynthesis in land plants occurs in the ____
• leaves.

7
Plant Physiology

• Roots
• Anchor the plant.
• Absorb raw materials needed for growth.
• Stem
• Supports the leaves.
• Contains the tissue used for transporting
  materials throughout the plant.
• Xylem phloem (like arteries veins)

8
Physiology Continued

• Leaf
• Thin, flat which provides maximum surface area
  for the absorption of light.
• Epidermis protects the inner cells.
• Cuticle waxy coating on some leaves.
• Palisade Cells tall cells containing
  chloroplasts which are filled with chlorophyll.
• Autotrophic nutrition occurs in the Palisade
  cells.
• Spongy Layer Loosely arranged cells separated
  by interconnected air spaces used for storing
  gases.
• Stomate micro openings on the leaf which allow
  for the exchange of gases.

9
The Mineral Needs of Plants

• Plant growth requires more than sunlight, carbon
  dioxide, chlorophyll, and water.
• Many plants require mineral substances derived
  from the decomposition of rock.
• Hydroponics is a method of growing plants in
  water enriched with mineral substances.
• Ten elements are essential to plants calcium,
  hydrogen, magnesium, oxygen, potassium, carbon,
  iron, nitrogen, phosphorus, and sulfur.
• Other trace elements are needed like manganese,
  zinc, copper.

10
Movement of Minerals into Plants

• Plant cells absorb minerals in two major ways
• Simple exchange through the cell membrane
  (diffusion)
• Reversible
• Moves from high concentration to low
• Happens quickly
• Active transport - the movement of a substance
  against its concentration.
• Irreversible
• Happens very slowly

11
Advantages of Hydroponic Gardening

• No weeds to pull means less competition.
• 2. No soil borne disease.
• Grow more plants in a smaller space.
• Plants grow more rapidly and produce larger
  yields.
• Produce is higher in nutritional value than field
  grown crops.
• 6. YOU CAN GARDEN ALL YEAR!       

12
Maintaining Greenhouse Conditions

• Temperature
• Regulates germination, growth, flowering,
  fruiting, longevity.
• - 75/65 F generally will work for most species.
• Humidity
• 50-90 RH generally
• Plants, wet soils and floors provide humidity.
• Mostly worry about disease promotion.
• Vent or heat or both if condensation lingers on
  glass past mid-morning.
• Pre-dawn venting

13
Continued

• Watering
• Quality--test clear water before growing your
  first plant. Direct yourself to do it regularly
  for clear water and fertilizer.
• QuantityDo not over water plants by putting on
  too much water at one time.
• Frequency--depends on weather, pot, soil,
  species, age.
• Application method--should be automated whenever
  possible.