Crop Production and Management – Short Answer Type Questions
Class 8
Science
Chapter 1
Crop Production and Management — 50 Short Answer Questions (Topic-wise)
CBSE Class 8 Science – Chapter Wise Study Materials Based on NCERT
CBSE Board Examinations — Chapter Presentation (Systematic):
- Unit Focus: Agricultural practices, crop classification, soil health, irrigation, pest control, harvesting and storage.
- Question Style: Short Answer (2–4 marks) — detailed but concise answers suitable for school and board tests.
- Exam Tip: Provide definitions, list steps, and give a short example where applicable to fetch full marks.
These Short Questions with Answers are designed strictly as per the NCERT syllabus, making them ideal for CBSE Class 8 board exams standard.
Topic 1: Basics of Crop Production (Questions 1–6)
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Q1: What is crop production? Briefly explain its importance.
A1: Crop production is the cultivation of plants for food, fibre, fuel and other uses. It is important because it provides food for humans and animals, raw materials for industries, and employment for a large population. Efficient crop production ensures food security and economic stability.
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Q2: Define agriculture and mention two objectives of agriculture.
A2: Agriculture is the practice of growing crops and rearing animals for human use. Objectives include (1) producing food and raw materials, and (2) earning livelihood and income for farmers.
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Q3: Explain what is meant by 'cropping season'.
A3: A cropping season is the period of the year when a particular crop is grown, determined by climatic conditions. Examples include the kharif season (monsoon crops) and rabi season (winter crops).
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Q4: Differentiate between kharif and rabi crops with examples.
A4: Kharif crops are sown with the onset of monsoon and harvested in autumn (e.g., paddy, maize). Rabi crops are sown in winter and harvested in spring (e.g., wheat, gram). Kharif needs more water; rabi needs cooler temperatures during sowing.
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Q5: What is mixed cropping? Give one advantage.
A5: Mixed cropping is growing two or more crops simultaneously on the same field. Advantage: It reduces the risk of total crop failure and can improve overall yield and soil protection.
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Q6: What is crop rotation and why is it practiced?
A6: Crop rotation is growing different crops in succession on the same land. It helps maintain soil fertility, reduces pest and disease build-up, and can improve crop yields over time.
Topic 2: Soil, Manure and Fertilizers (Questions 7–14)
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Q7: Describe the composition of soil and its role in crop production.
A7: Soil is made of mineral particles, organic matter, water, and air. It supplies nutrients, water and physical support to plants. The topsoil is rich in organic matter and is most fertile, supporting root growth and microbial activity.
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Q8: What is organic manure? List two examples.
A8: Organic manure is decomposed plant and animal waste added to soil to improve fertility and structure. Examples: farmyard manure (FYM) and compost.
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Q9: What are chemical fertilizers and why are they used?
A9: Chemical fertilizers are inorganic compounds that supply specific nutrients like nitrogen (N), phosphorus (P), and potassium (K) to plants. They are used to meet immediate nutrient deficiencies and boost crop yields.
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Q10: Compare manure and fertilizers (two points).
A10: Manure improves soil structure and releases nutrients slowly; fertilizers provide specific nutrients quickly. Manure is organic and eco-friendly; excessive use of chemical fertilizers may cause soil and water pollution.
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Q11: Explain how adding organic matter benefits soil.
A11: Organic matter improves soil texture, increases water retention, supports beneficial microbes, and slowly releases nutrients, leading to healthier plant growth and sustained fertility.
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Q12: Define soil erosion and mention one control measure.
A12: Soil erosion is the removal of the topsoil by wind or water. Control measure: Planting cover crops, building terraces, or using windbreaks to reduce runoff and wind speed.
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Q13: What is vermicompost and how is it prepared?
A13: Vermicompost is nutrient-rich compost produced using earthworms. Prepared by layering biodegradable waste with soil and adding earthworms in a moist environment; worms decompose the waste into rich humus.
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Q14: Why is testing soil important before applying fertilizers?
A14: Soil testing reveals nutrient deficiencies and pH levels, helping to apply the right type and amount of fertilizer, avoiding wastage and preventing soil degradation or pollution.
Topic 3: Steps in Crop Production (Questions 15–24)
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Q15: List the main steps involved in crop production.
A15: Main steps: selection of seeds, preparation of soil (ploughing and levelling), sowing, adding manure and fertilizers, irrigation, weeding, harvesting, threshing, winnowing and storage.
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Q16: Explain the purpose of ploughing.
A16: Ploughing turns and loosens the soil, buries crop residues, and helps mix organic matter. It improves aeration, root penetration and water infiltration, preparing the seedbed for sowing.
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Q17: Describe two methods of sowing seeds.
A17: Broadcasting: scattering seeds by hand over the field; simple but uneven. Dibbling/line sowing: placing seeds at regular intervals in rows using a dibbler or seed drill for uniform growth and easy weeding.
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Q18: Why is levelling important after ploughing?
A18: Levelling ensures uniform water distribution, prevents waterlogging or dry spots, and makes sowing and irrigation more effective.
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Q19: What is seed treatment and when is it done?
A19: Seed treatment involves treating seeds with fungicides or bio-agents before sowing to protect them from soil-borne diseases and pests, improving germination rates.
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Q20: Explain the processes of threshing and winnowing.
A20: Threshing separates grains from stalks by beating or machines. Winnowing separates lighter chaff from heavier grains using air flow or a winnowing fan after threshing.
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Q21: What is the role of weeding in crop production?
A21: Weeding removes unwanted plants that compete with crops for nutrients, water and light, leading to better growth and yields for the main crop.
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Q22: How does timely harvesting affect crop yield?
A22: Timely harvesting ensures crops are collected at optimum maturity, reducing losses from shattering, pest attack or lodging, and preserving quality and yield.
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Q23: Why is proper storage necessary after harvesting?
A23: Proper storage protects produce from insects, rodents, moisture and fungal growth, maintaining quality and preventing post-harvest losses.
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Q24: Mention two modern tools/machines used in agriculture.
A24: Tractor (for ploughing and transport) and combine harvester (for harvesting and threshing combined in one operation).
Topic 4: Irrigation Techniques (Questions 25–30)
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Q25: What is irrigation and why is it necessary?
A25: Irrigation is the artificial supply of water to crops when rainfall is inadequate. It is necessary to ensure growth, prevent drought stress and achieve good yields in dry periods.
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Q26: Describe drip irrigation and its benefits.
A26: Drip irrigation delivers water slowly and directly to the plant root zone through pipes and emitters. Benefits include water conservation, reduced weed growth and efficient nutrient delivery.
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Q27: Explain sprinkler irrigation and when it is preferred.
A27: Sprinkler irrigation sprays water over crops like rainfall using pipes and rotating sprinklers. It is preferred on uneven land, orchards, and areas where water application needs to be uniform over the field.
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Q28: Name two traditional water sources used for irrigation.
A28: Canals and wells/tube wells are traditional sources. Canals distribute river water; wells tap groundwater.
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Q29: How does over-irrigation harm crops?
A29: Over-irrigation can cause waterlogging, root rot, nutrient leaching and reduced oxygen in soil, leading to poor plant growth and increased disease incidence.
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Q30: What is rainwater harvesting and its advantage in agriculture?
A30: Rainwater harvesting collects and stores rainwater for later use. Advantage: It supplements irrigation needs, recharges groundwater and reduces dependence on external water sources.
Topic 5: Protection from Pests and Diseases (Questions 31–36)
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Q31: List common types of crop pests.
A31: Common pests include insects (aphids, stem borers), rodents (rats), nematodes and pathogenic fungi, bacteria and viruses that cause diseases.
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Q32: What precautions should be taken while using chemical pesticides?
A32: Use recommended doses, follow safety guidelines, wear protective gear, avoid spraying during flowering to protect pollinators, and prevent contamination of water sources.
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Q33: Explain biological control with an example.
A33: Biological control uses natural enemies to reduce pest populations. Example: Introducing Trichogramma wasps to parasitize and control caterpillar eggs.
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Q34: How does crop rotation help in pest management?
A34: Rotating crops disrupts pest life cycles and reduces build-up of crop-specific pests and diseases, thereby lowering infestation levels naturally.
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Q35: What is integrated pest management (IPM)?
A35: IPM is a sustainable approach combining biological, cultural and chemical methods to manage pests economically and with minimal environmental impact.
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Q36: Give one cultural practice that reduces pest attack.
A36: Early sowing or timely planting can avoid peak pest periods; removing crop residues reduces pest habitats.
Topic 6: Harvesting, Threshing and Storage (Questions 37–42)
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Q37: What factors determine the time of harvesting?
A37: Factors include crop maturity, moisture content, weather conditions and market demand. Harvesting at the right time preserves quality and yield.
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Q38: Describe the process of threshing and its purpose.
A38: Threshing separates grains from the crop stalks using manual beating or machines. It facilitates grain collection and prepares produce for winnowing and storage.
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Q39: Explain winnowing and how it helps post-harvest processing.
A39: Winnowing separates lighter chaff from heavier grains by allowing wind or fan to blow away chaff. It cleans the produce and reduces impurities before storage.
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Q40: Mention two common storage problems and one solution for each.
A40: Problems: insect attack and moisture leading to mold. Solutions: Proper drying and using airtight containers or fumigation where necessary.
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Q41: How does proper drying help in storage?
A41: Drying reduces moisture content, preventing fungal growth and insect infestation, thereby prolonging shelf life and maintaining quality.
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Q42: What are combine harvesters and their advantage?
A42: Combine harvesters are machines that cut, thresh and clean grains in one operation. Advantage: Saves time and reduces manual labor, increasing efficiency.
Topic 7: Sustainable Practices & Environment (Questions 43–47)
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Q43: What is organic farming and its main principle?
A43: Organic farming avoids synthetic chemicals and relies on natural inputs and processes like composting, crop rotation and biological pest control to maintain soil health and biodiversity.
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Q44: Describe the role of crop rotation in maintaining soil fertility.
A44: Crop rotation alternates crops with different nutrient demands and root structures, preventing nutrient depletion, breaking pest cycles, and improving soil organic matter and structure.
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Q45: How do chemical fertilizers contribute to environmental issues if misused?
A45: Excessive fertilizer use can leach into water bodies causing eutrophication, contaminate groundwater, and degrade soil health over time by disturbing microbial balance.
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Q46: Suggest two water conservation practices suitable for farms.
A46: Practices: drip irrigation to reduce water use and rainwater harvesting to store and use rainfall for irrigation; both conserve water and recharge groundwater.
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Q47: Explain integrated nutrient management (briefly).
A47: Integrated nutrient management combines organic manures, chemical fertilizers and biofertilizers in appropriate proportions to maintain soil fertility and crop productivity sustainably.
Topic 8: Practical Applications & Revision (Questions 48–50)
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Q48: Outline a simple classroom activity to demonstrate seed germination.
A48: Place seeds (e.g., moong) between moist cotton in a transparent plate or paper towel, keep in a warm place, and observe root and shoot emergence over days. Change water to prevent fungal growth.
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Q49: Describe a small vermicompost setup for school demonstration.
A49: Use a wooden or plastic box with drainage, layer garden waste and cow dung, add earthworms (e.g., Eisenia fetida), maintain moisture and shade; collect compost after a few weeks as dark, crumbly humus.
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Q50: How should students use NCERT to prepare for exams on this chapter?
A50: Read chapter explanations, practise end-of-chapter questions, reproduce key diagrams, make short notes and flashcards for terms, and attempt previous year questions based on NCERT topics.
Note: All Short Answer Questions with Answers are organized topic-wise and strictly follow the NCERT syllabus, making them ideal for CBSE Class 8 board exams standard.