Agronomy Basic 5 — Questions and Answers
Question 1: What is 'salinization' in agricultural soils?
- The addition of organic matter to improve soil structure
- The accumulation of soluble salts to harmful levels in soil (Correct answer)
- The process of lowering soil pH with sulfur
- A method of seed treatment before planting
Correct answer: The accumulation of soluble salts to harmful levels in soil
Salinization occurs when evaporation leaves behind soluble salts that accumulate to concentrations toxic to most crops.
Question 2: Which practice is used to reduce soil erosion on sloped farmland by plowing across the slope?
- Strip cropping
- Contour farming (Correct answer)
- Terracing
- Wind breaks
Correct answer: Contour farming
Contour farming involves tilling and planting across the slope rather than up and down, slowing runoff and reducing erosion.
Question 3: What does 'germination rate' measure in seed quality testing?
- The speed at which seeds absorb water
- The percentage of seeds that sprout under standard conditions (Correct answer)
- The weight of seeds per unit area planted
- The depth at which seeds should be planted
Correct answer: The percentage of seeds that sprout under standard conditions
Germination rate is the percentage of seeds in a sample that successfully sprout under controlled, optimal conditions.
Question 4: What is the primary function of potassium (K) in crop plants?
- Building plant proteins
- Regulating stomatal opening and improving disease resistance (Correct answer)
- Providing energy for photosynthesis
- Stimulating root nodule formation
Correct answer: Regulating stomatal opening and improving disease resistance
Potassium regulates stomata to control water use, activates enzymes, and strengthens cell walls, improving overall stress and disease resistance.
Question 5: Which of the following is an example of a C4 crop plant?
- Wheat
- Soybean
- Corn (maize) (Correct answer)
- Rice
Correct answer: Corn (maize)
Corn (maize) is a C4 plant, using a more efficient photosynthetic pathway that reduces photorespiration and performs well in hot, sunny conditions.
Question 6: What term describes the ability of soil to allow water to move downward through its layers?
- Field capacity
- Permeability (Correct answer)
- Wilting point
- Bulk density
Correct answer: Permeability
Soil permeability (or hydraulic conductivity) refers to how easily water can flow through the pores between soil particles.
Question 7: In agronomy, what is meant by 'yield potential' of a crop variety?
- The average yield achieved on a typical farm
- The maximum yield achievable under ideal growing conditions with no limiting factors (Correct answer)
- The yield expected after accounting for typical pest losses
- The minimum yield required for the crop to be economically viable
Correct answer: The maximum yield achievable under ideal growing conditions with no limiting factors
Yield potential is the theoretical maximum output a crop variety can produce when grown without resource limitations such as water, nutrients, or pests.
Agronomy Basic 5
What is 'salinization' in agricultural soils?