PCA PLANT PATHOGENS EXAM LATEST

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PCA PLANT PATHOGENS EXAM LATEST 2025 / 2026 |

COMPLETE QUESTIONS AND VERIFIED DETAILED

ANSWERS/ LATEST EXAM!!!

7. The nonliving components of an ecosystem are called:

• Biotic compounds
• Abiotic compounds
• Mineral components
• Environmental components - Answer-B. Abiotic

compounds

• Which of the following ecological concepts is illustrated

in a food web?

• Population equilibrium
• mutualism
• Biogeochemical cycles
• Competition - Answer-B. mutualism

• What is a limiting factor?
• A biotic factor that stops the growth of a plant of animal 1 / 4

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• A factor that is required for the growth and survival of an

organism

• One of many soil nutrients that regulates the growth of

a plant

• An action made by a consumer that limits the

population size of a species - Answer-B. A factor that is required for the growth and survival of an organism

• The mean population level around which a species'

characteristic abundance fluctuates is the species?

• Density dependence
• Equilibrium position
• Population density
• Abundance level - Answer-B. Equilibrium position

• Many agricultural pest species such as foliar

pathogens, aphids, mites and small seeded weeds are

considered:

• S strategists
• K strategists
• R strategists
• C strategists - Answer-C. R strategists 2 / 4

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• In general, how does the amount of biodiversity in an

agroecosystem compare to that of a natural, more mature

ecosystem? Biodiversity level is:

• Equal among most ecosystems
• Lower in an agroecosystem than a natural system
• Higher in an agroecosystem than a natural system
• Not measureable in agroecosystems - Answer-B. Lower

in an agroecosystem than a natural system

13. The goal of pest eradication is generally:

• To eliminate newly invading pests
• Aimed a eliminating exotic pests from a given county
• To reduce existing pest populations
• To discourage damaging pest populations form

occurring in a given area - Answer-A. To eliminate newly invading pests

14. Secondary pests are pests that:

• Damage crop plants but do not kill them
• Become prevalent after control actions have been taken

to control key pests 3 / 4

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• Damage the crop plant but do not damage the

harvested part

• Harm crop plants but never cause enough damage to

be economically important - Answer-B. Become prevalent after control actions have been taken to control key pests

• What is the relationship between a treatment threshold

and an economic injury level?

• A treatment threshold is always higher than the

economic injury level

• An economic injury level is always higher than the

treatment threshold

• Economic injury levels are equal to treatment

thresholds

• Economic injury levels have been determined for all

classes of pests buy treatment thresholds have not. - Answer-B. An economic injury level is always higher than the treatment threshold

• What is the "aesthetic injury level"?
• The population level of a pest at which foliar damage

will occur

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