Agronomy Basic 4 — Questions and Answers
Question 1: What does the 'dormancy' period of a seed mean?
- The seed is dead and will not germinate
- The seed is alive but will not germinate under current conditions (Correct answer)
- The seed has been treated with fungicide
- The seed coat has been removed
Correct answer: The seed is alive but will not germinate under current conditions
Seed dormancy is a survival mechanism where a viable seed will not germinate even under otherwise favorable conditions until specific requirements are met.
Question 2: In a standard NPK fertilizer labeled 10-20-10, what does the middle number represent?
- Nitrogen percentage
- Phosphorus (P₂O₅) percentage (Correct answer)
- Potassium (K₂O) percentage
- Sulfur percentage
Correct answer: Phosphorus (P₂O₅) percentage
The middle number in an NPK label represents the percentage of available phosphate (P₂O₅) in the fertilizer.
Question 3: Which type of irrigation delivers water directly to the root zone with minimal evaporation loss?
- Flood irrigation
- Sprinkler irrigation
- Drip irrigation (Correct answer)
- Furrow irrigation
Correct answer: Drip irrigation
Drip irrigation delivers water slowly and directly to the root zone through emitters, greatly reducing evaporation and water waste.
Question 4: What is the term for plants that complete their life cycle in one growing season?
- Perennial
- Biennial
- Annual (Correct answer)
- Ephemeral
Correct answer: Annual
Annual plants germinate, grow, flower, set seed, and die all within a single growing season.
Question 5: Which soil horizon is typically referred to as the 'topsoil'?
- O horizon
- A horizon (Correct answer)
- B horizon
- C horizon
Correct answer: A horizon
The A horizon is the topsoil layer, rich in organic matter and biological activity, and most important for crop production.
Question 6: What is 'integrated pest management' (IPM)?
- Using only chemical pesticides to eliminate all pests
- A strategy combining biological, cultural, and chemical controls to minimize pest damage economically (Correct answer)
- Releasing large quantities of beneficial insects to replace all pesticides
- A government program for regulating pesticide sales
Correct answer: A strategy combining biological, cultural, and chemical controls to minimize pest damage economically
IPM uses a combination of biological, cultural, mechanical, and chemical methods to control pests while minimizing environmental impact and costs.
Question 7: Which gas is fixed by nitrogen-fixing bacteria in legume root nodules?
- Carbon dioxide (CO₂)
- Oxygen (O₂)
- Atmospheric nitrogen (N₂) (Correct answer)
- Methane (CH₄)
Correct answer: Atmospheric nitrogen (N₂)
Rhizobium bacteria in legume root nodules convert atmospheric nitrogen gas (N₂) into ammonium, a form plants can use.
Agronomy Basic 4
What does the 'dormancy' period of a seed mean?