Benefit of Greenhouse Production Flashcards
Quiz 2
Define sustainability
Able to be maintained at a certain level/rate conserving an ecological balance by avoiding depletion of natural resources.
Name the 3 pillars of sustainability
1) Environmental: ecological integrity maintained and resourced consumed at rate of replenishment
2) Economic: generates enough profit to ensure operations to continue
3) Social: communities and citizens healthy, safe and secure in relation to human rights.
Benefits of GH production
1) Potential for improved yields: by reducing plants exposure to harsh climates=higher output
2) Soilless production: improved land efficiency (don’t need acres of great soil), local production can lead to less transportation needed to get produce to people = lower carbon footprint.
3 Potential to provide alt.IMP (integrated pest management)
What are the 3 things that impact a pest/disease out break in a GH (Plant Pest Triangle)
*need all three for outbreak to occur, if u can stop/ change course of one it can be avoided.
1) Host/Crop
2) Environment
3) Plant/Pest
Provide 2 examples of optimal use of resources
1) Collect and use recirculated run off water and nutrient solutions by using a closed irrigation system
2) Improve structures and equipment, such as using thermal energy curtains to reduce heat loss at night (can reduce energy cost of GH 30-40%)
Name 5 of the things you should consider when doing GH production plans.
*5 of any of these
1) Sales and Marketing (need a market to sell the product, needs to be sellable to cover the costs)
2) Greenhouse Design and Facility Planning
3) Labour Planning
4) Maintenance Planning
5) Energy Planning
6) Future Planning
7) Financial Planning
6 Aspects that need to work together for successful GH production.
1) Type of production system and plant support.
2) Climate and growing strategies.
3) Structure and equipment (do purchases or arrangements need to be made?).
4) Irrigation systems (know crop requirements to make decision).
5) Substrate selection (strong iteration with water).
6) Environmental control systems (how accurate it is).
Define crop physiology
The study of the internal processes responsible for plant growth, development and the production of crop yields.
What is ‘Forcing’?
An attempt to grow a crop in a GH to produce a higher yield than normals or to produce a crop outside its normal growing conditions.
Explain Photosynthesis
-occurs in the chloroplasts
-the process in which light energy is converted to chemical energy in the form of sugars
Explain Respiration
-the opposite of photosynthesis
-occurs in the mitochondrion
-used for the process of growth and development in the plant
How does light intensity affect photosynthesis and respiration?
a) as light increases the rate of photosynthesis increases to a point of saturation
b) uses a wavelength of 400-700nm also know as PAR, most effective wave length for photosynthesis
What is Light Compensation Point?
lowest intensity needed, below which no growth occurs, indicates need for supplemental lighting
Explain Light Saturation Point
Light intensity that will maximize the rate of photosynthesis, indicates need for supplemental light or shading.
What does DLI stand for and what is it?
Optimal Daily Light Integral: ideal amount of light radiation in the PAR wavelength.
How does temperature affect photosynthesis and respiration?
As temperature increases the rate of photosynthesis increases to a max. but then decreases with further temp increases.
Temperature is also the primary influence on the rates of respiration. As temp increases the rate of respiration also increases.
What is a base temperature?
Lowest temp, below which plants can not grow, an indication for supplemental heating.
Max. Threshold Temperature?
The highest temp, above which plant is under heat stress and no growth will occur (plant will eventually die).
How does Carbon Dioxide Availability affect photosynthesis and respiration?
As the concentration of CO2 increases the rate of photosynthesis increases to a point of saturation. Ambient CO2
What is crop Phenology?
The study of changes in the timing of the life cycle events such as germination, seeding development, vegetative stage, reproductive stages.
Name three examples of Circadian Rhythms
1)temperatures
2)daylength/ seasonal
3)plant stress
What is photoperiodism?
Plant flowering response to length of day/night in a 24 hour cycle.
Short day plant vs. long vs. neutral?
Short day: requires shorter day length for flowering
Long day: requires longer day length, such as easter lily
day Neutral: irregardless will flower, typically tomatoes and cucumbers.
obligative response vs facultative?
Obligative: A plant that needs the exact correct day length otherwise will not flower.
Facultative: ***
