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Chapter 12: Improvement in Food Resources

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1. Introduction

  • Importance of Food: Provides proteins, carbohydrates, fats, vitamins, minerals for growth and health.
  • Need for Increased Production: India’s population > 1 billion; needs > 250 million tonnes grain/year; limited land expansion.
  • Revolutions: Green Revolution (food grains), White Revolution (milk); increased resource use, risking environmental balance.
  • Sustainability: Increase production without degrading environment; use sustainable practices (mixed farming, intercropping, integrated farming).
  • Food Security: Depends on food availability and access; increasing farmer incomes combats hunger.

Activity: Discuss why food production must increase!

2. Improvement in Crop Yields

  • Crop Types (Fig. 12.1):
    • Cereals (wheat, rice, maize, millets, sorghum): Carbohydrates.
    • Pulses (gram, pea, black gram, green gram, pigeon pea, lentil): Proteins.
    • Oilseeds (soyabean, groundnut, sesame, castor, mustard, linseed, sunflower): Fats.
    • Vegetables, fruits, spices: Vitamins, minerals.
    • Fodder crops (berseem, oats, sudan grass): Livestock feed.
  • Seasons:
    • Kharif (June–October): Paddy, soyabean, pigeon pea, maize, cotton, green gram, black gram.
    • Rabi (November–April): Wheat, gram, peas, mustard, linseed.
    • Activity 12.2: Collect grains/seeds; note sowing/harvesting seasons.
  • Yield Increase: 4x food grain production (1952–2010) with 25% land increase via:
    • Crop variety improvement.
    • Crop production improvement.
    • Crop protection management.
  • Questions:
    • 1. Cereals: Carbohydrates; Pulses: Proteins; Fruits/Vegetables: Vitamins, minerals.
  • 2.1 Crop Variety Improvement:
    • Methods: Hybridisation (intervarietal, interspecific, intergeneric); genetic modification (introduce desired genes).
    • Factors:
      • Higher yield: Increase productivity/acre.
      • Improved quality: Baking (wheat), protein (pulses), oil (oilseeds), preservation (fruits/vegetables).
      • Biotic/abiotic resistance: Against diseases, insects, drought, salinity, etc.
      • Shorter maturity: Economical, allows multiple crops/year.
      • Wider adaptability: Stable yields across climates.
      • Desirable agronomic traits: Tall fodder crops, dwarf cereals.
    • Questions:
      • 1. Biotic (diseases, insects) and abiotic (drought, salinity) stresses reduce yields.
      • 2. Agronomic traits: Tallness/branching (fodder), dwarfness (cereals).
  • 2.2 Crop Production Management:
    • Nutrient Management:
      • Nutrients: Air (carbon, oxygen), water (hydrogen, oxygen), soil (13 nutrients, Table 12.1).
      • Macronutrients (large quantities): Nitrogen, phosphorus, potassium, calcium, magnesium, sulphur.
      • Micronutrients (small quantities): Iron, manganese, boron, zinc, copper, molybdenum, chlorine.
      • Deficiency: Affects growth, reproduction, disease susceptibility.
      • Manure: Organic matter, nutrients; improves soil structure, water retention (sandy soils), drainage (clayey soils).
      • Types: Compost, vermi-compost (decomposed waste); green manure (sun hemp, guar).
      • Fertilizers: Supply nitrogen, phosphorus, potassium; ensure vegetative growth.
      • Issues: Overuse causes water pollution, soil fertility loss.
      • Organic Farming: Minimal chemicals, uses manures, bio-agents, healthy cropping systems.
      • Questions:
        • 1. Macronutrients: Needed in large quantities for growth.
        • 2. Plants get nutrients from air, water, soil.
        • 3. Manure: Long-term fertility, organic; Fertilizers: Short-term yield, chemical, may harm soil.
    • Irrigation:
      • Rain-fed farming risks crop failure; irrigation ensures water supply.
      • Systems: Wells (dug, tube), canals, river lift systems, tanks.
      • Initiatives: Rainwater harvesting, watershed management (check-dams).
    • Cropping Patterns:
      • Mixed Cropping: Two+ crops simultaneously (e.g., wheat + gram); reduces risk.
      • Intercropping: Two+ crops in patterns (Fig. 12.2); maximizes nutrient use, pest control.
      • Crop Rotation: Different crops in succession; improves yield, soil health.
    • Questions:
      • 1. (c) Best: Quality seeds, irrigation, fertilizers, crop protection maximize yield.
  • 2.3 Crop Protection Management:
    • Weeds: Unwanted plants (e.g., Xanthium, Parthenium); compete for resources.
    • Insect Pests: Cut plants, suck sap, bore stems/fruits.
    • Diseases: Caused by bacteria, fungi, viruses.
    • Control: Pesticides (herbicides, insecticides, fungicides), mechanical removal, resistant varieties, summer ploughing.
    • Activity 12.1: List weeds, pests in garden/field.
    • Questions:
      • 1. Preventive/biological methods: Less toxic, environmentally friendly.
      • 2. Storage losses: Biotic (insects, fungi), abiotic (moisture, temperature).
  • Storage of Grains:
    • Losses: Due to biotic (insects, rodents) and abiotic (moisture, temperature) factors.
    • Prevention: Cleaning, drying (sunlight, shade), fumigation.

Activity: Identify crops in your area!

3. Animal Husbandry

  • Definition: Scientific management of livestock (feeding, breeding, disease control).
  • Nutritional Values (Table 12.2):
    • Milk (cow): 3.6% fat, 4% protein, 4.5% sugar, 0.7% minerals, 87.2% water, vitamins B1, B2, B12, D, E.
    • Egg: 12% fat, 13% protein, 1% minerals, 74% water, vitamins B2, D.
    • Meat: 3.6% fat, 21.1% protein, 1.1% minerals, 74.2% water, vitamins B2, B12.
    • Fish: 2.5% fat, 19% protein, 1.3% minerals, 77.2% water, vitamins Niacin, D, A.
  • 3.1 Cattle Farming:
    • Purposes: Milk (milch animals), draught labour (e.g., tilling).
    • Species: Bos indicus (cows), Bos bubalis (buffaloes).
    • Breeding: Cross-breeding exotic (Jersey, Brown Swiss; long lactation) with local breeds (Red Sindhi, Sahiwal; disease resistance) (Fig. 12.3).
    • Management: Clean, ventilated sheds; sloping floors; regular brushing.
    • Feed: Roughage (fibre), concentrates (protein, nutrients), feed additives (micronutrients).
    • Diseases: External/internal parasites, bacterial/viral infections; prevented by vaccination.
    • Activity 12.3: Visit cattle farm; note breeds, milk production.
    • Questions:
      • 1. Cross-breeding: Combines desired traits (milk yield, disease resistance).
  • 3.2 Poultry Farming:
    • Purposes: Egg production (layers), meat (broilers).
    • Breeding: Cross-breeding Indian (Aseel) with exotic (Leghorn) for chick quality, summer tolerance, low maintenance, fibrous diet use.
    • Management: Temperature, hygiene, feed (protein, vitamins A, K for broilers; Fig. 12.4).
    • Diseases: Viral, bacterial, fungal, nutritional; prevented by sanitation, vaccination.
    • Activity 12.4: Visit poultry farm; note breeds, ration, housing.
    • Questions:
      • 1. Poultry: Efficiently converts low-fibre waste into protein-rich food.
      • 2. Common practices: Hygiene, feed, disease control; Differences: Broilers (meat, high protein) vs. layers (eggs, different housing).
  • 3.3 Fish Production:
    • Methods: Capture fishing (natural), culture fishery (farming).
    • Marine Fisheries: 7500 km coastline; fish (pomphret, mackerel, tuna, sardines, Bombay duck), prawns, oysters (Fig. 12.5); uses satellites, echo-sounders.
    • Inland Fisheries: Canals, ponds, rivers, estuaries; composite fish culture (Catla, Rohu, Mrigal, Common Carp, Grass Carp; Fig. 12.6) uses non-competing species.
    • Challenges: Limited seed availability; solved by hormonal breeding.
    • Activity 12.5: Visit fish farm; note varieties, ponds, feed, production.
    • Questions:
      • 1. Fish: Capture (natural), culture (farming).
      • 2. Composite fish culture: Non-competing species maximize food use, increase yield.
  • 3.4 Bee-Keeping:
    • Purpose: Honey, wax production; low-investment enterprise (Fig. 12.7).
    • Species: Apis cerana indica, A. dorsata, A. florae, A. mellifera (Italian, high yield, less stinging).
    • Pasturage: Flowers for nectar/pollen; affects honey taste, quality.
    • Questions:
      • 1. Desirable traits: High honey yield, less stinging, long hive stay, good breeding.
      • 2. Pasturage: Flower availability determines honey taste/quantity.

Activity: Explore animal farming in your area!

4. Exercises

  • Exercise Questions:
    • 1. Intercropping: Different crops in patterns; maximizes nutrient use, reduces pest spread, increases yield.
    • 2. Manure/fertilizers: Supply nutrients, enhance growth, increase yield.
    • 3. Intercropping: Better nutrient use, pest control; Crop rotation: Soil health, multiple harvests.
    • 4. Genetic manipulation: Introduces desired genes (e.g., disease resistance); improves yield, quality.
    • 5. Storage losses: Biotic (insects, fungi), abiotic (moisture, temperature).
    • 6. Animal husbandry: Increases milk, egg, meat production; improves farmer income.
    • 7. Cattle farming: Milk, draught labour; improves nutrition, income.
    • 8. Common: Cross-breeding for improved traits, scientific management.
    • 9. Capture fishing: Natural waters; Mariculture: Marine culture; Aquaculture: Inland culture.

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