questions and CORRECT answers
Soilless Substrate Components - CORRECT ANSWER Peat
Perlite
Vermiculite
Bark
Coir
Rice/Coconut Husk
Chemical Selection Criteria of Substrates - CORRECT ANSWER C:N Ratio
AEC
pH
CEC
Alkalinity
Salinity
EC
Physical Selection Criteria of Substrates - CORRECT ANSWER Air Holding Capacity
Water Holding Capacity
Low bulk density
Inert
Uniform
Stable
(+ cost and availability)
Environmental Factors Controlled in Greenhouses - CORRECT ANSWER Water
Air Composition
Ventilation
, Nutritional Needs
Light
Humidity
Temperature
Ventilation
People Working
Disadvantages of Greenhouse - CORRECT ANSWER Moisture Control
Insects/Pests
Disease
Cost of Structure
Temp/Ventilation Control
Roles of Water in Plants - CORRECT ANSWER Solvent
Structure
Transport
Cooling
Food/Photosyn.
Pump/Pressure Control
Why SOIL is NOT used in GH system - CORRECT ANSWER 1. Low water holding
cap.
2. Low air cap.
3. Not ideal pH
4. Soil's high EC
5. Soil is not easily controlled
6. Soil is a valuable Resource