Agricultural/Bioengineering Greenhouse and Controlled Environment Agriculture 2

Question 1

CO2 enrichment in greenhouses is used to:

Accepted Answer

Increase photosynthesis rate and crop yield above levels supported by ambient CO2

Answer

Elevating CO2 to 800-1200 ppm in greenhouses increases the rate of photosynthesis, resulting in faster growth and higher yields compared to ambient 420 ppm.

Question 2

Integrated Pest Management (IPM) in greenhouses often uses biological control agents such as:

Accepted Answer

Beneficial insects like predatory mites and parasitic wasps to control pests

Answer

Greenhouse IPM uses beneficial organisms — such as Phytoseiulus persimilis for spider mites — to naturally suppress pest populations, reducing pesticide dependence.

Question 3

The growing medium perlite is widely used in greenhouse production because it:

Accepted Answer

Offers excellent drainage and aeration while being lightweight and inert

Answer

Perlite is a volcanic glass expanded by heat into lightweight, porous particles that provide excellent aeration and drainage while being chemically inert and disease-free.

Question 4

Heating degree days (HDD) are used in greenhouse engineering to:

Accepted Answer

Estimate seasonal heating energy requirements for a greenhouse in a given climate

Answer

HDD quantifies the cumulative temperature difference below a base temperature over a season, used to size and estimate costs for greenhouse heating systems.

Question 5

Electrical conductivity (EC) of nutrient solutions is routinely measured in hydroponics to:

Accepted Answer

Monitor total dissolved nutrient concentration and adjust feeding accordingly

Answer

EC measures the concentration of dissolved ions in nutrient solutions, serving as a proxy for overall nutrient strength that growers monitor and adjust continuously.

Agricultural/Bioengineering Practice Test

Agricultural/Bioengineering Practice Test

Agricultural/Bioengineering Greenhouse and Controlled Environment Agriculture 2