Class 9 Science Chapter 12 Notes

Improvement In Food Resources Class 9 Science Chapter 12 notes are available here. These notes are made by the subject experts of our team.

Improvement In Food Resources Class 9 Science Chapter 12 Notes

1. Food and Nutrients:

• All living organisms need food.
• Food provides proteins, carbohydrates, fats, vitamins, and minerals.
• These nutrients are essential for body development, growth, and health.

2. Sources of Food:

• Major sources of food include plants and animals.
• Most food is obtained from agriculture and animal husbandry.

3. Need for Increased Production:

• Efforts are being made to improve production from agriculture and animal husbandry.
• Current production levels are insufficient due to India’s large and growing population.
• India’s population exceeds one billion and continues to grow.
• More than a quarter of a billion tonnes of grain will be needed annually.

4. Challenges in Increasing Production:

• Increasing food production by expanding farming land is limited because India is already intensively cultivated.
• There is little scope for increasing the cultivated land area.

5. Solution:

• It is necessary to increase production efficiency for both crops and livestock to meet the growing food demand.

6. Successes in Increasing Food Production:

• Efforts to meet food demand have seen some success.
• The Green Revolution increased food-grain production.
• The White Revolution improved milk availability and efficiency.

7. Impact on Natural Resources:

• Intensive use of natural resources can lead to environmental damage.
• There is a risk of disrupting the balance of natural resources.

8. Sustainable Practices:

• It’s crucial to increase food production without harming the environment.
• Sustainable practices in agriculture and animal husbandry are needed.

9. Addressing Malnutrition and Hunger:

• Increasing grain production alone does not solve malnutrition and hunger.
• People need financial means to access food.
• Food security depends on food availability and access.

10. Economic Considerations:

• A large part of the population relies on agriculture for their livelihood.
• Increasing incomes of agricultural workers is essential to combat hunger.

11. Scientific Management and Farming Practices:

• Scientific management practices should be adopted for high yields.
• Mixed farming, intercropping, and integrated farming practices are recommended.
• Combining agriculture with livestock, poultry, fisheries, or beekeeping can ensure sustained livelihoods.

Improvement in Crop Yields

1. Cereals and Carbohydrates:

• Cereals such as wheat, rice, maize, millets, and sorghum provide carbohydrates for energy.

2. Pulses and Proteins:

• Pulses, including gram (chana), pea (matar), black gram (urad), green gram (moong), pigeon pea (arhar), and lentil (masoor), provide protein.

3. Oilseeds and Fats:

• Oilseeds such as soybean, groundnut, sesame, castor, mustard, linseed, and sunflower provide necessary fats.

4. Vegetables, Spices, and Fruits:

• These provide a range of vitamins and minerals, along with small amounts of proteins, carbohydrates, and fats.

5. Fodder Crops:

• Fodder crops like berseem, oats, or sudan grass are cultivated as food for livestock.

6. Climatic Requirements for Crops:

• Different crops require specific climatic conditions, temperature, and photoperiods for growth and completing their life cycle.
• Photoperiods refer to the duration of sunlight, affecting plant growth and flowering.

7. Crop Seasons:

• Kharif crops are grown during the rainy season (June to October), including paddy, soybean, pigeon pea, maize, cotton, green gram, and black gram.
• Rabi crops are grown in the winter season (November to April), including wheat, gram, peas, mustard, and linseed.

8. Increase in Food Grain Production:

• From 1952 to 2010, there was a fourfold increase in food grain production in India, with only a 25% increase in cultivable land area.

9. Stages of Farming Practices:

• Farming involves three stages:
  1. Choice of seeds for planting.
  2. Nurturing of crop plants.
  3. Protection of growing and harvested crops from loss.

10. Categories for Improving Crop Yields:

• Crop variety improvement
• Crop production improvement
• Crop protection management

Crop Variety Improvement

1. Purpose of Crop Variety Improvement:

• The goal is to find crop varieties that yield well.

2. Breeding for Useful Characteristics:

• Crops can be bred for disease resistance, response to fertilizers, product quality, and high yields.

3. Hybridization:

• Hybridization involves crossing genetically dissimilar plants.
• Types of hybridization include:
  • Intervarietal: between different varieties.
  • Interspecific: between different species of the same genus.
  • Intergeneric: between different genera.

4. Genetic Modification:

• Crop improvement can involve introducing genes to provide desired traits, resulting in genetically modified crops.

5. Acceptance of New Varieties:

• New varieties must produce high yields under diverse conditions.
• Farmers need access to high-quality seeds of uniform variety that germinate consistently.

6. Relation to Weather, Soil, and Water:

• Cultivation practices and crop yields depend on weather, soil quality, and water availability.
• Varieties that can grow in diverse climatic conditions are beneficial due to unpredictable weather like droughts and floods.
• Varieties tolerant to high soil salinity have been developed.

7. Factors for Variety Improvement:

• Higher Yield: Increase crop productivity per acre.
• Improved Quality: Quality varies by crop, such as baking quality in wheat, protein quality in pulses, oil quality in oilseeds, and preserving quality in fruits and vegetables.
• Biotic and Abiotic Resistance:
  • Biotic stresses include diseases, insects, and nematodes.
  • Abiotic stresses include drought, salinity, waterlogging, heat, cold, and frost.
  • Resistant varieties can improve crop production.
• Change in Maturity Duration:
  • Shorter crop duration from sowing to harvesting is more economical.
  • Allows for multiple crop cycles per year.
  • Short duration reduces production costs and simplifies harvesting with uniform maturity.
• Wider Adaptability:
  • Varieties with wider adaptability stabilize production across different environments.
  • One variety can be grown under various climatic conditions.
• Desirable Agronomic Characteristics:
  • Tallness and branching are desirable for fodder crops.
  • Dwarfness is desired in cereals to consume fewer nutrients.
  • Developing varieties with desired agronomic traits enhances productivity.

Crop production Management

1. Diversity in Farm Sizes:

• Farming in India varies from small to very large farms.

2. Access to Resources:

• Farmers have varying levels of land, money, and access to information and technologies.

3. Financial Conditions Influence Farming:

• Financial conditions determine the farming practices and agricultural technologies farmers can adopt.

4. Correlation Between Inputs and Yields:

• Higher inputs often lead to higher yields.

5. Impact of Purchasing Capacity:

• A farmer’s ability to purchase inputs influences their cropping system and production practices.

6. Levels of Production Practices:

• Production practices can be categorized into:
  • ‘No cost’ production
  • ‘Low cost’ production
  • ‘High cost’ production practices

Nutrient Management

1. Nutrient Importance:

• Plants require nutrients for development, growth, and well-being.

2. Sources of Nutrients:

• Nutrients are supplied to plants by air, water, and soil.
• Air provides carbon and oxygen.
• Water provides hydrogen and oxygen.
• Soil provides thirteen essential nutrients.

3. Types of Nutrients:

• Macronutrients: Required in large quantities; include nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur.
• Micronutrients: Required in small quantities; include iron, manganese, boron, zinc, copper, molybdenum, and chlorine.

4. Nutrient Deficiency:

• Deficiencies affect physiological processes in plants, including reproduction, growth, and disease susceptibility.

5. Enriching Soil:

• Soil can be enriched with nutrients through manure and fertilizers to increase yield.

Manure

1. Composition of Manure:

• Manure contains large quantities of organic matter and small quantities of nutrients.

2. Preparation of Manure:

• Manure is prepared by decomposing animal excreta and plant waste.

3. Benefits of Manure:

• Enriches soil with nutrients and organic matter.
• Increases soil fertility.
• Improves soil structure by increasing water holding capacity in sandy soils.
• Enhances drainage and prevents waterlogging in clayey soils.

4. Environmental and Recycling Benefits:

• Using manure reduces the need for chemical fertilizers, protecting the environment.
• Manure recycles biological waste material and farm waste.

5. Types of Manure:

• Compost and Vermi-compost:
  • Composting involves decomposing farm waste like livestock excreta, vegetable waste, and straw in pits.
  • Vermi-composting uses earthworms to speed up decomposition.
• Green Manure:
  • Plants like sun hemp or guar are grown and then ploughed into the soil before sowing crops.
  • Green manure enriches the soil with nitrogen and phosphorus.

Fertilizers

1. Purpose of Fertilizers:

• Fertilizers are commercially produced plant nutrients.
• They supply essential nutrients like nitrogen, phosphorus, and potassium.
• Fertilizers promote good vegetative growth, including leaves, branches, and flowers, leading to healthy plants.

2. Role in Farming:

• Fertilizers contribute to higher yields, especially in high-cost farming.

3. Application Considerations:

• Proper dose, timing, and pre- and post-application precautions are necessary for effective use.
• Excessive irrigation can wash away fertilizers, preventing plant absorption and leading to water pollution.

4. Impact on Soil Fertility:

• Continuous use of fertilizers can deplete soil fertility.
• Fertilizers do not replenish organic matter, and they can harm soil microorganisms.

5. Balancing Short-term and Long-term Benefits:

• The short-term benefits of fertilizers and the long-term benefits of manure should be considered for maintaining soil fertility and achieving optimal crop yields.

6. Definition of Organic Farming:

• Organic farming involves minimal or no use of chemicals such as fertilizers, herbicides, and pesticides.
• It maximizes the use of organic manures and recycled farm wastes like straw and livestock excreta.

7. Use of Bio-Agents:

• Bio-agents, such as cultures of blue-green algae, are used in biofertilizer preparation.
• Neem leaves or turmeric are used as bio-pesticides, particularly in grain storage.

8. Healthy Cropping Systems:

• Cropping systems like mixed cropping, intercropping, and crop rotation are integral to organic farming.
• These systems help in controlling insects, pests, and weeds while providing nutrients.

Irrigation

1. Dependence on Rain-fed Agriculture:

• Most agriculture in India relies on rain-fed systems, where the success of crops depends on timely monsoons and sufficient rainfall throughout the growing season.
• Poor monsoons can lead to crop failure.

2. Importance of Timely Watering:

• Providing water to crops at the right stages during their growing season can increase yields.

3. Irrigation Measures:

• Various irrigation measures are used to increase agricultural land under irrigation due to diverse water resources and climate in India.

4. Types of Irrigation Systems:

• Wells:
  • Two types: dug wells and tube wells.
  • Dug wells collect water from water-bearing strata, while tube wells tap water from deeper strata.
  • Water is lifted by pumps for irrigation.
• Canals:
  • An extensive irrigation system where canals receive water from reservoirs or rivers.
  • Main canals divide into branch canals with further distributaries to irrigate fields.
• River Lift Systems:
  • Used where canal flow is insufficient or irregular.
  • Water is drawn directly from rivers to supplement irrigation near rivers.
• Tanks:
  • Small storage reservoirs that intercept and store runoff from smaller catchment areas.

5. New Initiatives:

• Rainwater Harvesting and Watershed Management:
  • Involves building small check-dams to increase groundwater levels.
  • Check-dams prevent rainwater from flowing away and reduce soil erosion.

Cropping Pattern

1. Mixed Cropping:

• Involves growing two or more crops simultaneously on the same piece of land, such as wheat + gram or groundnut + sunflower.
• Reduces risk and provides insurance against the failure of one crop.

2. Inter-cropping:

• Involves growing two or more crops simultaneously on the same field in a definite pattern, e.g., soybean + maize or finger millet (bajra) + cowpea (lobia).
• Crops are selected with different nutrient requirements to ensure maximum nutrient utilization and prevent the spread of pests and diseases.
• Provides better returns for both crops.

3. Crop Rotation:

• Involves growing different crops on a piece of land in a planned succession.
• Crop rotation varies in duration and crop combinations.
• The choice of crops is influenced by moisture availability and irrigation facilities.
• Proper crop rotation can lead to two or three good harvests per year.

Crop Protection Management

1. Threats to Field Crops:

• Field crops are infested by weeds, insect pests, and diseases.
• Weeds and pests can cause significant crop damage and loss if not controlled timely.

2. Weeds:

• Weeds are unwanted plants in cultivated fields, such as Xanthium (gokhroo), Parthenium (gajar ghas), and Cyperinus rotundus (motha).
• They compete for food, space, and light, taking up nutrients and reducing crop growth.
• Early removal of weeds is essential for a good harvest.

3. Insect Pests:

• Insects attack plants by:
  • Cutting roots, stems, and leaves.
  • Sucking cell sap from various parts of the plant.
  • Boring into stems and fruits.
• These activities affect crop health and reduce yields.

4. Plant Diseases:

• Diseases are caused by pathogens such as bacteria, fungi, and viruses.
• Pathogens can be transmitted through soil, water, and air.

5. Control Methods:

• Pesticides (herbicides, insecticides, and fungicides) are commonly used to control weeds, insects, and diseases.
• Pesticides are applied to crop plants or used for treating seeds and soil.
• Excessive use of pesticides can be harmful to plant and animal species and cause environmental pollution.

6. Weed Control Techniques:

• Mechanical removal of weeds.
• Preventive methods include:
  • Proper seed bed preparation.
  • Timely sowing of crops.
  • Intercropping and crop rotation.

7. Pest Prevention Measures:

• Use of resistant varieties.
• Summer ploughing, which involves deep ploughing in summer to destroy weeds and pests.

Storage Of Grains

1. High Storage Losses:

• Agricultural produce can suffer significant losses during storage.

1. Causes of Storage Losses:

• Biotic factors: Insects, rodents, fungi, mites, and bacteria.
• Abiotic factors: Inappropriate moisture and temperatures.

1. Effects of Storage Losses:

• Quality degradation.
• Weight loss.
• Poor germinability.
• Discoloration of produce.
• Reduced marketability.

1. Control of Storage Losses:

• Proper treatment and systematic management of warehouses.

1. Preventive and Control Measures:

• Strict cleaning of produce before storage.
• Proper drying of produce, first in sunlight and then in shade.
• Fumigation using chemicals to kill pests.

Animal Husbandry

1. Definition of Animal Husbandry:

• Scientific management of animal livestock.

2. Aspects of Animal Husbandry:

• Includes feeding, breeding, and disease control.

3. Types of Animal-Based Farming:

• Includes cattle, goat, sheep, poultry, and fish farming.

4. Increasing Demand:

• Rising population and living standards increase demand for milk, eggs, and meat.

5. Humane Treatment:

• Growing awareness of the need for humane treatment of livestock introduces new limitations in livestock farming.

6. Need for Improvement:

• Livestock production requires improvement to meet increasing demand and humane treatment standards.

Cattle Farming

1. Purposes of Cattle Husbandry:

• Milk production.
• Draught labor for agricultural work such as tilling, irrigation, and carting.

2. Species of Indian Cattle:

• Bos indicus: Cows.
• Bos bubalis: Buffaloes.

3. Types of Cattle:

• Milch animals: Milk-producing females.
• Draught animals: Used for farm labor.

4. Milk Production:

• Depends on the lactation period, which is the period of milk production after the birth of a calf.
• Increasing the lactation period can increase milk production.

5. Breeds:

• Exotic or foreign breeds (e.g., Jersey, Brown Swiss) are selected for long lactation periods.
• Local breeds (e.g., Red Sindhi, Sahiwal) show excellent disease resistance.
• Cross-breeding can combine desirable qualities of both exotic and local breeds.

6. Cleaning and Shelter for Cows and Buffaloes:

• Proper cleaning and shelter facilities are essential for humane farming, animal health, and clean milk production.
• Regular brushing is necessary to remove dirt and loose hair.
• Animals should be sheltered in well-ventilated, roofed sheds to protect them from rain, heat, and cold.
• The floor of the cattle shed should be sloping to stay dry and facilitate cleaning.

7. Food Requirements:

• Maintenance Requirement: Food needed to support a healthy life.
• Milk Producing Requirement: Food needed during the lactation period.
• Animal feed includes:
  • Roughage: Largely fiber.
  • Concentrates: Low in fiber, high in proteins, and other nutrients.
• Cattle need balanced rations with all nutrients in proportionate amounts.
• Feed additives containing micronutrients promote health and milk output.

8. Cattle Diseases:

• Diseases can cause death and reduce milk production.
• A healthy animal feeds regularly and has a normal posture.
• Parasites:
  • External parasites: Live on the skin and cause skin diseases.
  • Internal parasites: Affect the stomach and intestine (worms) and damage the liver (flukes).
• Infectious diseases are caused by bacteria and viruses.
• Vaccinations are given to farm animals against major viral and bacterial diseases.

Poultry farming

1. Purpose of Poultry Farming:

• To raise domestic fowl for egg production and chicken meat.

2. Types of Poultry Breeds:

• Layers: Raised for egg production.
• Broilers: Raised for meat production.

3. Cross-Breeding Programs:

• Involve breeding Indian (e.g., Aseel) and foreign (e.g., Leghorn) breeds to develop new varieties.

4. Desirable Traits in Poultry Breeds:

• Number and Quality of Chicks: Improvement in the quantity and quality of offspring.
• Dwarf Broiler Parent: For commercial chick production.
• Summer Adaptation Capacity: Tolerance to high temperatures.
• Low Maintenance Requirements: Reduction in care and upkeep.
• Efficient Feed Utilization: Ability to utilize fibrous, cheaper diets made from agricultural by-products.

Egg And Broiler Production

1. Broiler Chicken Production:

• Feed: Broiler chickens are given vitamin-rich supplementary feed to promote good growth and feed efficiency.
• Care: Emphasis on avoiding mortality, maintaining feathering, and ensuring high carcass quality.
• Purpose: Broilers are raised for meat and sent to market for this purpose.

2. Management Practices:

• Temperature and Hygiene: Essential for maintaining housing conditions and poultry feed.
• Disease and Pest Control: Crucial for good poultry production.

3. Different Requirements:

• Broilers vs. Egg Layers: Broilers and egg layers have different housing, nutritional, and environmental needs.

Fish Production

1. Importance of Fish:

• Fish is a cheap source of animal protein.

2. Types of Fish Production:

• Capture Fishing: Obtaining fish from natural resources.
• Culture Fishery: Obtaining fish through fish farming.

3. Water Sources:

• Fish can be obtained from both seawater (marine ecosystems) and fresh water (rivers and ponds).

Marine Fisheries

1. Marine Fishery Resources:

• India has 7500 km of coastline and deep seas for marine fisheries.

2. Popular Marine Fish Varieties:

• Pomphret, mackerel, tuna, sardines, and Bombay duck.

3. Fishing Methods:

• Various fishing nets and boats are used.
• Yields are increased by locating fish schools using satellites and echo-sounders.

4. Mariculture:

• High-value marine fish and shellfish are farmed in seawater.
• Includes finned fishes (e.g., mullets, bhetki, pearl spots), shellfish (e.g., prawns, mussels, oysters), and seaweed.
• Oysters are cultivated for pearls.

5. Demand and Depletion:

• As marine fish stocks deplete, demand is increasingly met by mariculture.

Inland Fisheries

1. Inland Freshwater Resources:

• Includes canals, ponds, reservoirs, and rivers.
• Brackish water resources like estuaries and lagoons are also important for fish.

2. Fishing Methods:

• Capture fishing is done in inland water bodies but yields are low.
• Most fish production comes from aquaculture.

3. Fish Culture:

• Can be done in combination with rice crops, where fish are grown in paddy fields.
• Intensive fish farming is conducted in composite fish culture systems.

4. Composite Fish Culture Systems:

• Uses a combination of five or six fish species in a single pond.
• Species are selected for their different food habits (e.g., surface feeders, middle-zone feeders, bottom feeders, and weed eaters) to optimize food use and avoid competition.
• Examples: Catlas (surface feeders), Rohus (middle-zone feeders), Mrigals and Common Carps (bottom feeders), Grass Carps (weed eaters).

5. Challenges and Solutions:

• Many fish breed only during monsoon, leading to mixed or poor-quality seed.
• Hormonal stimulation methods have been developed to breed fish in ponds and ensure the supply of pure seed in desired quantities.

Bee-Keeping

1. Purpose of Bee-Keeping:

• Beekeeping is primarily for honey production.
• It is an additional income-generating activity with low investment.

2. Additional Products:

• Beehives also provide wax, used in various medicinal preparations.

3. Bee Varieties:

• Local Varieties:
  • Apis cerana indica (Indian bee)
  • A. dorsata (rock bee)
  • A. florae (little bee)
• Exotic Variety:
  • A. mellifera (Italian bee), used to increase honey yield.
  • Italian bees are preferred for their high honey collection capacity, lower tendency to sting, longer hive residency, and good breeding.

4. Commercial Production:

• Bee farms or apiaries are established for honey production.

5. Honey Quality Factors:

• Depends on pasturage: the availability of flowers for nectar and pollen.
• The type of flowers affects the taste of the honey.