Certified Crop Advisor Exam Practice Questions
And Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. Which of the following is the primary macronutrient
required in the largest quantity for plant growth?
a. Iron
b. Zinc
c. Nitrogen
d. Manganese
Nitrogen is a primary macronutrient essential for vegetative
growth and is required in the largest amounts by plants.
2. The pH of a soil primarily affects:
a. Soil texture
b. Nutrient availability
c. Organic matter content
d. Soil depth
Soil pH influences the solubility of nutrients, affecting plant
uptake and potential deficiencies or toxicities.
3. Leguminous crops improve soil fertility mainly through:
a. Photosynthesis
b. Irrigation
c. Nitrogen fixation
d. Weed suppression
Legumes form symbiotic relationships with Rhizobium
bacteria, which convert atmospheric nitrogen into forms
plants can use.
, 4. Which of the following is considered a micronutrient?
a. Nitrogen
b. Phosphorus
c. Potassium
d. Boron
Boron is required in very small quantities but is essential for
cell wall formation and reproductive growth.
5. The term “field capacity” refers to:
a. The soil moisture when the soil is completely dry
b. The point of wilting
c. The amount of water remaining after excess has
drained
d. Total precipitation
Field capacity is the water content held in the soil after
gravitational water has drained, available for plants.
6. Which practice reduces soil erosion most effectively?
a. Tillage
b. Cover cropping
c. Overgrazing
d. Removing crop residue
Cover crops protect soil from wind and water erosion and
improve soil structure.
7. The main purpose of a soil test is to:
a. Determine soil texture
b. Assess nutrient levels for fertilization decisions
c. Measure soil depth
d. Identify soil organisms
,Soil tests help determine nutrient deficiencies or excesses
and guide fertilizer applications.
8. Which irrigation method is considered most water-
efficient?
a. Flood
b. Furrow
c. Drip
d. Sprinkler
Drip irrigation delivers water directly to the root zone,
minimizing losses from evaporation or runoff.
9. The C:N ratio in compost affects:
a. Soil pH
b. Rate of decomposition
c. Soil texture
d. Pest resistance
A high carbon-to-nitrogen (C:N) ratio slows decomposition,
while a low ratio speeds it up.
10. Which of the following is a symptom of nitrogen
deficiency?
a. Purple leaf edges
b. Yellowing of older leaves
c. Leaf curling
d. Necrotic spots on young leaves
Nitrogen is mobile in the plant, so deficiency symptoms
appear first on older leaves as chlorosis.
11. Which tillage practice minimizes soil disturbance
and helps retain organic matter?
a. Conventional plowing
, b. Strip-tillage
c. No-till
d. Deep ripping
No-till reduces soil erosion, preserves soil structure, and
maintains organic matter.
12. Phosphorus deficiency is most likely to show as:
a. Yellowing of lower leaves
b. Wilting
c. Purpling of older leaves
d. Leaf curling
Phosphorus is relatively immobile in plants, and deficiency
often causes dark purple coloration in older leaves.
13. Potassium is important in plants primarily for:
a. Chlorophyll synthesis
b. Water regulation and enzyme activation
c. Nitrogen fixation
d. Root hair development
Potassium helps regulate water balance, stomatal function,
and activates enzymes critical for growth.
14. Which soil texture holds the most water?
a. Sand
b. Clay
c. Silt
d. Loam
Clay soils have small particles and high surface area,
allowing them to retain more water than sandy soils.
And Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. Which of the following is the primary macronutrient
required in the largest quantity for plant growth?
a. Iron
b. Zinc
c. Nitrogen
d. Manganese
Nitrogen is a primary macronutrient essential for vegetative
growth and is required in the largest amounts by plants.
2. The pH of a soil primarily affects:
a. Soil texture
b. Nutrient availability
c. Organic matter content
d. Soil depth
Soil pH influences the solubility of nutrients, affecting plant
uptake and potential deficiencies or toxicities.
3. Leguminous crops improve soil fertility mainly through:
a. Photosynthesis
b. Irrigation
c. Nitrogen fixation
d. Weed suppression
Legumes form symbiotic relationships with Rhizobium
bacteria, which convert atmospheric nitrogen into forms
plants can use.
, 4. Which of the following is considered a micronutrient?
a. Nitrogen
b. Phosphorus
c. Potassium
d. Boron
Boron is required in very small quantities but is essential for
cell wall formation and reproductive growth.
5. The term “field capacity” refers to:
a. The soil moisture when the soil is completely dry
b. The point of wilting
c. The amount of water remaining after excess has
drained
d. Total precipitation
Field capacity is the water content held in the soil after
gravitational water has drained, available for plants.
6. Which practice reduces soil erosion most effectively?
a. Tillage
b. Cover cropping
c. Overgrazing
d. Removing crop residue
Cover crops protect soil from wind and water erosion and
improve soil structure.
7. The main purpose of a soil test is to:
a. Determine soil texture
b. Assess nutrient levels for fertilization decisions
c. Measure soil depth
d. Identify soil organisms
,Soil tests help determine nutrient deficiencies or excesses
and guide fertilizer applications.
8. Which irrigation method is considered most water-
efficient?
a. Flood
b. Furrow
c. Drip
d. Sprinkler
Drip irrigation delivers water directly to the root zone,
minimizing losses from evaporation or runoff.
9. The C:N ratio in compost affects:
a. Soil pH
b. Rate of decomposition
c. Soil texture
d. Pest resistance
A high carbon-to-nitrogen (C:N) ratio slows decomposition,
while a low ratio speeds it up.
10. Which of the following is a symptom of nitrogen
deficiency?
a. Purple leaf edges
b. Yellowing of older leaves
c. Leaf curling
d. Necrotic spots on young leaves
Nitrogen is mobile in the plant, so deficiency symptoms
appear first on older leaves as chlorosis.
11. Which tillage practice minimizes soil disturbance
and helps retain organic matter?
a. Conventional plowing
, b. Strip-tillage
c. No-till
d. Deep ripping
No-till reduces soil erosion, preserves soil structure, and
maintains organic matter.
12. Phosphorus deficiency is most likely to show as:
a. Yellowing of lower leaves
b. Wilting
c. Purpling of older leaves
d. Leaf curling
Phosphorus is relatively immobile in plants, and deficiency
often causes dark purple coloration in older leaves.
13. Potassium is important in plants primarily for:
a. Chlorophyll synthesis
b. Water regulation and enzyme activation
c. Nitrogen fixation
d. Root hair development
Potassium helps regulate water balance, stomatal function,
and activates enzymes critical for growth.
14. Which soil texture holds the most water?
a. Sand
b. Clay
c. Silt
d. Loam
Clay soils have small particles and high surface area,
allowing them to retain more water than sandy soils.
