20 Multiple Choice Questions on Agriculture with Answers and Explanations

1. What is the primary purpose of crop rotation?

A) To increase soil fertility
B) To reduce pest and disease buildup
C) To improve water retention
D) All of the above

Answer: D) All of the above
Explanation: Crop rotation helps maintain soil fertility, prevents pest and disease cycles, and improves soil structure and water retention.

2. Which of the following is a Rabi crop?

A) Rice
B) Wheat
C) Cotton
D) Maize

Answer: B) Wheat
Explanation: Rabi crops are winter-season crops, sown in October-November and harvested in April-May. Wheat is a major Rabi crop.

3. What is the main component of organic farming?

A) Chemical fertilizers
B) Pesticides
C) Manure and compost
D) Hybrid seeds

Answer: C) Manure and compost
Explanation: Organic farming avoids synthetic chemicals and relies on natural fertilizers like manure and compost.

4. Which gas is primarily responsible for the greenhouse effect in agriculture?

A) Oxygen
B) Carbon dioxide
C) Nitrogen
D) Hydrogen

Answer: B) Carbon dioxide
Explanation: CO₂ is a major greenhouse gas contributing to global warming, affecting agricultural productivity.

5. What is the ideal pH range for most crops?

A) 3.0 - 4.5
B) 5.5 - 7.5
C) 8.0 - 9.5
D) 1.0 - 2.0

Answer: B) 5.5 - 7.5
Explanation: Most crops thrive in slightly acidic to neutral soil (pH 5.5-7.5).

6. Which irrigation method is the most water-efficient?

A) Flood irrigation
B) Drip irrigation
C) Sprinkler irrigation
D) Furrow irrigation

Answer: B) Drip irrigation
Explanation: Drip irrigation delivers water directly to plant roots, minimizing wastage.

7. What is the primary function of nitrogen in plants?

A) Enhances root growth
B) Aids in chlorophyll production
C) Improves fruit sweetness
D) Strengthens stems

Answer: B) Aids in chlorophyll production
Explanation: Nitrogen is essential for chlorophyll, which is crucial for photosynthesis.

8. Which of the following is a Kharif crop?

A) Barley
B) Mustard
C) Rice
D) Peas

Answer: C) Rice
Explanation: Kharif crops are monsoon-dependent and include rice, maize, and cotton.

9. What is the process of converting atmospheric nitrogen into plant-usable form called?

A) Nitrification
B) Denitrification
C) Nitrogen fixation
D) Ammonification

Answer: C) Nitrogen fixation
Explanation: Nitrogen fixation converts atmospheric nitrogen (N₂) into ammonia (NH₃), usable by plants.

10. Which soil type has the smallest particle size?

A) Sand
B) Silt
C) Clay
D) Loam

Answer: C) Clay
Explanation: Clay has the finest particles, leading to high water retention but poor drainage.

11. What is the main benefit of agroforestry?

A) Increases monoculture farming
B) Reduces biodiversity
C) Combines trees and crops for sustainability
D) Depletes soil nutrients

Answer: C) Combines trees and crops for sustainability
Explanation: Agroforestry integrates trees with crops, improving soil health and biodiversity.

12. Which pesticide is banned due to its harmful effects on bees?

A) Glyphosate
B) Neonicotinoids
C) DDT
D) Malathion

Answer: B) Neonicotinoids
Explanation: Neonicotinoids are linked to bee population decline and are restricted in many countries.

13. What is the primary cause of soil erosion?

A) Overgrazing
B) Deforestation
C) Heavy rainfall
D) All of the above

Answer: D) All of the above
Explanation: Soil erosion is accelerated by human activities like deforestation and natural factors like rain.

14. Which crop is known as the "Golden Fiber"?

A) Cotton
B) Jute
C) Silk
D) Hemp

Answer: B) Jute
Explanation: Jute is called the "Golden Fiber" due to its shiny, golden-brown color and economic value.

15. What is hydroponics?

A) Soil-based farming
B) Water-based farming without soil
C) Organic composting
D) Traditional crop rotation

Answer: B) Water-based farming without soil
Explanation: Hydroponics grows plants in nutrient-rich water solutions instead of soil.

16. Which Indian state is the largest producer of sugarcane?

A) Punjab
B) Uttar Pradesh
C) Maharashtra
D) Karnataka

Answer: B) Uttar Pradesh
Explanation: Uttar Pradesh leads in sugarcane production due to favorable climate and irrigation.

17. What is the main purpose of the Green Revolution?

A) Promote organic farming
B) Increase agricultural productivity using HYV seeds
C) Reduce chemical fertilizer use
D) Encourage traditional farming

Answer: B) Increase agricultural productivity using HYV seeds
Explanation: The Green Revolution introduced high-yielding varieties (HYV) to boost food production.

18. Which microorganism helps in decomposing organic matter in soil?

A) Viruses
B) Bacteria
C) Algae
D) Fungi

Answer: B) Bacteria
Explanation: Soil bacteria break down organic matter, enriching the soil with nutrients.

19. What is the primary use of a combine harvester?

A) Plowing fields
B) Harvesting and threshing crops
C) Spraying pesticides
D) Irrigating fields

Answer: B) Harvesting and threshing crops
Explanation: A combine harvester performs harvesting, threshing, and cleaning in one operation.

20. Which farming practice helps in carbon sequestration?

A) No-till farming
B) Excessive tilling
C) Overuse of fertilizers
D) Monocropping

Answer: A) No-till farming
Explanation: No-till farming reduces soil disturbance, helping store carbon in the soil.