Class 9 Science – Chapter 15: Improvement in Food Resources (Detailed Notes)

Class 9 Science – Chapter 15: Improvement in Food Resources (Detailed Notes)

1. Introduction

• Food is essential for all living organisms to grow, repair, and perform life processes.
• With increasing population, there is a need to improve the quality and quantity of food.
• Improvement in food resources includes better crop yield, protection from pests, and improved animal husbandry.

2. Improvement in Crop Yield

• Crop variety improvement: Developing better varieties of crops with higher yield, better quality, and resistance to diseases and pests.
• Methods used: hybridization, selection, genetic modification.
• Characteristics developed: high yield, early maturity, resistance to biotic (pests, diseases) and abiotic (drought, salinity) stresses.

3. Crop Production Management

• Nutrient Management:
  • Plants require nutrients for growth, which are classified as macronutrients and micronutrients.
  • Manure: Organic substance prepared from the decomposition of animal excreta and plant waste. Improves soil texture and fertility.
  • Fertilizers: Chemical substances rich in specific nutrients (e.g., urea, NPK). They increase yield quickly but may degrade soil quality if overused.
  • Integrated Nutrient Management: Use of both manure and fertilizers for best results.
• Irrigation:
  • Regular water supply is essential for crop growth.
  • Sources: wells, canals, rivers, dams, rainwater harvesting.
  • Modern methods: drip irrigation, sprinkler system (efficient and conserves water).
• Cropping Patterns:
  • Mixed cropping: Two or more crops grown simultaneously on the same land.
  • Intercropping: Two crops grown in a definite row pattern to reduce competition and increase productivity.
  • Crop rotation: Growing different crops one after another to maintain soil fertility.

4. Crop Protection Management

• Crops are attacked by weeds, insects, pests, and diseases.
• Weeds: Unwanted plants removed by weedicides or manual methods.
• Pests: Insects and animals that damage crops; controlled by pesticides and biological methods.
• Disease control: Using disease-resistant varieties, proper spacing, and fungicides.

5. Storage of Grains

• Proper storage is essential to prevent damage from moisture, rodents, fungi, and pests.
• Drying before storage, use of airtight containers, and fumigation are common methods.

6. Animal Husbandry

• The practice of raising animals for food, milk, eggs, wool, etc.
• Includes cattle farming, poultry farming, fish production, and bee-keeping.

i. Cattle Farming

• Milk and draught animals are bred and maintained.
• Improved breeds are developed for higher milk yield and disease resistance.
• Proper shelter, feed, and healthcare are essential.

ii. Poultry Farming

• Raising domesticated birds like chickens for eggs and meat.
• Improved breeds are used for higher productivity and disease resistance.

iii. Fish Production (Pisciculture)

• Includes capture fishing (natural resources) and culture fishing (fish farming).
• Types: Inland fisheries (ponds, rivers) and marine fisheries (sea/ocean).

iv. Bee-Keeping (Apiculture)

• Bees are reared for honey and wax.
• Apis indica (Indian bee) is a common species used.
• Bee-keeping helps in pollination of crops too.