📘 Class 9 Science : (Improvement in food resources)

🌾 Introduction

  • Food is essential for survival.

  • With increasing population, food production must also increase.

  • Science and technology have contributed to improving food production through agriculture, animal husbandry, and fisheries.

🔹 Improvement in Crop Yields

🔿 Methods of Crop Improvement

Method Description
Traditional Breeding Cross between two plants to get better varieties.
Hybridization Crossing two different varieties to get desirable traits.
Genetic Engineering Direct manipulation of genes to produce better crops.

🔿 Factors for Improvement

Factor Description
Crop Variety Improvement Developing better breeds for higher yield, disease resistance.
Crop Production Improvement Use of better practices and techniques.
Crop Protection Improvement Protection against pests, diseases, and weeds.

🌿 Crop Variety Improvement

🔿 Objectives

  • Higher yield

  • Improved quality

  • Resistance to biotic (pests, diseases) and abiotic (drought, heat) stresses

  • Shorter maturity period

  • Better adaptability to different conditions

🔿 Techniques

  • Selection

  • Hybridization (intervarietal, interspecific, intergeneric)

  • Genetic modification (transgenic crops)

🌿 Crop Production Management

🔿 Levels of Management

Level Description
Nutritional Providing proper manures and fertilizers.
Irrigation Providing water at correct stages of crop growth.
Cropping Patterns Managing cropping methods for maximum yield.

🔿 Nutrient Management

Source Examples Purpose
Manure Organic waste, dung Improves soil fertility and structure.
Fertilizers Urea, NPK fertilizers Provides specific nutrients rapidly.

🔿 Types of Nutrients

  • Macronutrients: N, P, K, Ca, Mg, S

  • Micronutrients: Zn, Fe, Cu, Mn, Mo, B, Cl

🔿 Methods of Manure Application

  • Broadcasting

  • Placement

  • Foliar spray

  • Fertigation

🔿 Irrigation Methods

Method Description
Traditional Moat (well irrigation), chain pump, lever system
Modern Sprinkler system, drip irrigation

Drip irrigation saves water and fertilizers by delivering it directly to roots.

🔿 Cropping Patterns

Type Description
Mixed Cropping Growing two or more crops simultaneously.
Intercropping Growing two or more crops in definite row patterns.
Crop Rotation Growing different crops alternately on the same land.

🌿 Crop Protection Management

🔿 Causes of Crop Loss

  • Pests (insects, rodents)

  • Pathogens (bacteria, fungi, viruses)

  • Weeds (unwanted plants)

🔿 Methods of Protection

  • Chemical control (insecticides, herbicides)

  • Biological control (using natural predators)

  • Cultural methods (crop rotation, timely sowing)

🔿 Storage Management

  • Proper drying, cleaning.

  • Use of silos, granaries.

  • Use of chemicals like fumigants to prevent pest attack.

🐕 Animal Husbandry

  • Definition: Scientific management of animal livestock.

  • Provides milk, meat, eggs, wool, hides.

🔿 Areas of Animal Husbandry

Area Description
Cattle Farming Management of cows and buffaloes for milk and draught labour.
Poultry Farming Rearing of domesticated birds for meat and eggs.
Fish Production Capture and culture fisheries.
Bee Keeping Rearing of bees for honey and wax.

🔿 Cattle Farming

Type Examples Purpose
Milch animals Cows (e.g., Sahiwal), buffaloes (e.g., Murrah) Milk production
Draught animals Bullocks Agricultural work

  • Improved breeds through cross-breeding.

  • Proper feeding, shelter, and hygiene essential.

🔿 Poultry Farming

  • Broilers: Raised for meat.

  • Layers: Raised for eggs.

  • Diseases: Bird flu, Ranikhet disease.

  • Careful vaccination is necessary.

🔿 Fish Production

Type Description
Capture Fishing Fishing from natural resources.
Culture Fishing Rearing fish in ponds (aquaculture).

  • Popular species: Rohu, Catla, Hilsa.

  • Composite fish culture: Different species together in one pond.

🔿 Bee-Keeping (Apiculture)

  • Production of honey and wax.

  • Bees: Apis indica is common in India.

  • Requires proper knowledge of flowering season and bee diseases.

📌 Key Points

  • Food production can be improved by better seeds, fertilizers, irrigation, and pest control.

  • Animal husbandry ensures a continuous supply of food and related products.

  • Scientific methods enhance quantity and quality of agricultural and animal products.

Hand written Notes Of CELL: The Fundamental unit of Life