Chapter 12: Improvement in Food Resourses
1. Introduction: The Challenge of Feeding a Nation
Imagine a giant dining table with over 1.4 billion people sitting around it. That is India. Every single person needs food to survive, grow, and stay healthy. Food gives us proteins, carbohydrates, fats, vitamins, and minerals. We get this food from two main sources: Agriculture (plants) and Animal Husbandry (animals).
The Problem: Our population is growing very fast, but our land is not growing. We cannot just cut down more forests to make farms because that would destroy the environment.
The Solution: Since we can’t increase the area of land, we must increase the efficiency. We need to grow more crops on the same piece of land. This is called increasing “production efficiency.” However, we must do this sustainably—meaning we shouldn’t damage the soil or environment so much that future generations can’t grow food.
Types of Crops
Different crops need different weather conditions to grow. In India, we divide them into two seasons:
- Kharif Crops: Grown in the rainy season (June to October). They need a lot of water.
Examples: Paddy (Rice), Soybean, Pigeon pea, Maize, Cotton. - Rabi Crops: Grown in the winter season (November to April). They need cool weather and less water.
Examples: Wheat, Gram, Peas, Mustard, Linseed.
2. Improvement in Crop Yields
To get a better harvest, farmers focus on three major steps. Think of it like baking a cake: first you pick the best ingredients (Variety Improvement), then you bake it carefully (Production Management), and finally, you stop anyone from stealing it (Protection Management).
2.1 Stage 1: Crop Variety Improvement
This step happens before planting. Scientists try to create “Super Seeds” that are better than normal seeds. They use a method called Hybridization.
What is Hybridization?
It is the crossing of two genetically dissimilar plants to create a new plant that has the best qualities of both parents. For example, if Parent A is “Very Strong” but produces less fruit, and Parent B is “Weak” but produces lots of fruit, the Hybrid child might be “Very Strong AND produce lots of fruit.”
Goals of Variety Improvement: Why do we do this?
- Higher Yield: To get more grain per acre of land.
- Improved Quality: Baking quality in wheat, protein quality in pulses, oil quality in oilseeds, or preserving quality in fruits.
- Biotic and Abiotic Resistance:
– Biotic: Resistance to living enemies like insects and diseases.
– Abiotic: Resistance to non-living stress like drought (no water), salinity (salty soil), heat, or cold. - Change in Maturity Duration: Making the crop grow faster. If a crop takes only 3 months instead of 5, the farmer saves money and can grow a second crop in the same year.
- Wider Adaptability: Creating seeds that can grow in many different climates, not just one specific area.
- Desirable Agronomic Traits:
– For Fodder crops (animal food): We want tall and leafy plants.
– For Cereals (grains): We want dwarf (short) plants so they consume fewer nutrients and don’t fall over easily.
2.2 Stage 2: Crop Production Management
This is the actual farming part. It involves money and management.
A. Nutrient Management
Just like humans need food, plants need nutrients. There are 16 essential nutrients for plants.
– Air supplies: Carbon, Oxygen.
– Water supplies: Hydrogen.
– Soil supplies: 13 nutrients.
These 13 soil nutrients are divided into two groups:
- Macronutrients (6): Required in large quantities (Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, Sulfur).
- Micronutrients (7): Required in very small quantities (Iron, Manganese, Boron, Zinc, Copper, Molybdenum, Chlorine).
How do we feed the soil?
- Manure: This is natural food for soil, made by decomposing animal waste (cow dung) and plant waste.
Benefits: It adds “humus” (organic matter) which improves soil structure. It makes sandy soil hold water better and helps clay soil drain water. It is slow but eco-friendly. - Fertilizers: These are chemical powders made in factories (like Urea, NPK).
Benefits: They give huge amounts of specific nutrients (Nitrogen, Phosphorus, Potassium) instantly. Plants grow very fast.
Drawbacks: Excessive use kills soil bacteria, causes water pollution, and destroys soil fertility in the long run.
B. Irrigation
India’s agriculture depends heavily on rain (Monsoons). But rain is unreliable. So, we use irrigation systems like:
– Wells: Tube wells tap into underground water.
– Canals: Man-made rivers bringing water from dams.
– River Lift Systems: Directly pumping water from nearby rivers.
– Tanks: Small reservoirs to store rainwater.
C. Cropping Patterns
Farmers use smart arrangements to maximize profit and reduce the risk of failure.
Visual Guide: Notice how Mixed Cropping is random, Intercropping is organized in rows, and Crop Rotation happens over time (one after another).
- Mixed Cropping: Growing two or more crops together in the same field. (e.g., Wheat + Gram).
Benefit: Insurance. If one crop fails due to bad weather, the other might survive. - Intercropping: Growing two or more crops in definite row patterns (e.g., 1 row of soybean, then 1 row of maize).
Benefit: Prevents pests from spreading to all plants. Makes harvesting easier than mixed cropping. - Crop Rotation: Growing different crops on a piece of land in a pre-planned succession. (e.g., Maize in Year 1, Mustard in Year 2).
Benefit: Some crops (like legumes) fix nitrogen in the soil, refilling the nutrients used by the previous crop. It prevents soil depletion.
2.3 Stage 3: Crop Protection Management
Once the crops are growing, enemies attack. We need to protect them from:
- Weeds: Unwanted plants (like Parthenium or Xanthium) that grow in the field. They steal sunlight, water, and nutrients from the main crop. We remove them by hand, by using machines, or by using weedicides.
- Insect Pests: Bugs that attack plants in three ways:
– They cut the root, stem, and leaf.
– They suck the cell sap (juice) from the plant.
– They bore into stems and fruits. - Diseases: Caused by pathogens like bacteria, fungi, and viruses.
Storage: Even after harvesting, grains can be ruined by moisture (fungi/mould) or pests (rats/insects). Grains must be dried thoroughly in the sun and then in shade before storing in clean, dry silos.
3. Animal Husbandry
This is the scientific management of livestock. As our population grows, the demand for milk, eggs, and meat increases.
3.1 Cattle Farming
Cows and buffaloes are raised for two reasons:
1. Milch Animals: Females that produce milk.
2. Draught Animals: Males used for hard labor (ploughing, carting).
Breeding:
– Exotic Breeds (Foreign): Like Jersey or Brown Swiss. They have long lactation periods (give milk for a long time).
– Indigenous Breeds (Local): Like Red Sindhi or Sahiwal. They are very tough and resistant to diseases.
The Strategy: We cross-breed them to get a cow that gives lots of milk (like Jersey) and doesn’t get sick easily (like Red Sindhi).
3.2 Poultry Farming
Raising chickens for food. There are two types of birds:
- Layers: Raised to lay eggs. They need calcium-rich food for strong shells.
- Broilers: Raised for meat. They are fed protein-rich and fat-rich food to grow big and fat very quickly (in just 6-8 weeks).
3.3 Fish Production (Pisciculture)
Fish is a cheap source of protein.
– Capture Fishing: Catching fish from natural sources (sea, rivers).
– Culture Fishery (Aquaculture): “Farming” fish in man-made ponds or tanks.
Composite Fish Culture
This is a super-efficient method. Imagine a 3-story building. If everyone lives on the ground floor, it gets crowded. But if some live on the ground, some on the 1st floor, and some on the 2nd, everyone is happy.
In a single pond, we put 5 or 6 species of fish that don’t fight for food because they eat from different “floors” of the pond.
The 3 Zones of a Pond:
1. Surface Feeders: Catlas (Eat floating food).
2. Middle Zone Feeders: Rohu (Eat algae in the middle).
3. Bottom Feeders: Mrigals and Common Carps (Eat weeds/waste at the bottom).
Result: The pond is clean, no food is wasted, and fish yield is maximum!
3.4 Bee-Keeping (Apiculture)
Farmers keep bee boxes to get Honey and Beeswax (used in medicines/polishes).
Common Bee: The Indian bee is Apis cerana indica.
The Superstar Bee: The Italian bee (Apis mellifera) is preferred for business because:
1. It produces lots of honey.
2. It stings less.
3. It stays in the beehive for a long time and breeds well.
4. Detailed Solutions to Practice Set
Here are the complete answers and explanations for the questions listed above.
Part A: Multiple-Choice Questions (MCQs) – Solutions
- Growing wheat and gram together in the same field is an example of:
Answer: c) Mixed cropping
Explanation: In mixed cropping, two seeds are mixed and sown without a specific row pattern. Wheat and Gram are a classic combination used to reduce the risk of total crop failure. - Which of the following is considered a micronutrient for plants?
Answer: c) Iron
Explanation: Nitrogen, Potassium, and Phosphorus are Macronutrients (needed in large amounts). Iron is a Micronutrient (needed in small traces). - Jersey and Brown Swiss are examples of:
Answer: b) Exotic cattle breeds
Explanation: These are foreign breeds known for long lactation periods. Indigenous (Indian) breeds would be Red Sindhi or Sahiwal. - The practice of growing 5-6 different fish species with different food habits in a single pond is called:
Answer: c) Composite fish culture
Explanation: This system maximizes yield by utilizing all zones of the pond (surface, middle, bottom). - Which of the following is NOT a benefit of using manure?
Answer: c) It provides a quick, concentrated supply of specific nutrients.
Explanation: This is a property of Fertilizers, not Manure. Manure provides small amounts of nutrients slowly, whereas fertilizers provide an instant “shot” of nutrients.
Part B: Short Answer Questions – Solutions
- What is the difference between a Kharif crop and a Rabi crop? Give one example of each.
Answer:
– Kharif Crops: Grown during the rainy season (June to October). They require substantial water. Example: Paddy (Rice) or Maize.
– Rabi Crops: Grown during the winter season (November to April). They require cool climates and less water. Example: Wheat or Mustard. - Why is crop rotation considered a beneficial practice for farmers?
Answer: Crop rotation maintains soil fertility. If the same crop is grown repeatedly, it drains specific nutrients from the soil. By rotating crops (e.g., planting legumes after cereals), the soil nutrients (especially nitrogen) are replenished naturally, reducing the need for chemical fertilizers and preventing soil depletion. - Differentiate between broilers and layers in poultry farming.
Answer:
– Broilers: Birds raised specifically for meat purposes. They are fed protein and fat-rich diets to grow fast and are sold in 6-8 weeks.
– Layers: Birds raised for egg production. They are raised to sexual maturity (20 weeks) and require a calcium-rich diet to produce healthy eggshells. - What is green manure and how is it prepared?
Answer: Green manure is a type of organic fertilizer. It is prepared by growing fast-growing plants like Sun hemp or Guar in the field. Once these plants grow, they are mulched (crushed) and ploughed back into the soil while still green. As they decompose, they enrich the soil with Nitrogen and Phosphorus. - Why is an Italian bee variety, Apis mellifera, often preferred for commercial honey production?
Answer: Apis mellifera is preferred because:
1. It has a high honey collection capacity.
2. It stings less compared to Indian varieties.
3. It stays in the beehive for longer periods and breeds very well, making management easier for farmers.
Part C: Long Answer Questions – Solutions
- What is hybridization? Explain the six main factors for which crop variety improvement is undertaken.
Answer:
Hybridization: It refers to crossing between genetically dissimilar plants to produce a new variety that combines the desirable characteristics of both parents.
Factors for Improvement:
1. Higher Yield: To increase productivity per hectare.
2. Improved Quality: Enhancing specific traits like baking quality in wheat or protein content in pulses.
3. Biotic and Abiotic Resistance: Developing crops resistant to pests/diseases (biotic) and environmental stress like drought/salinity (abiotic).
4. Change in Maturity Duration: Reducing the time from sowing to harvesting allows farmers to grow multiple crops in a year.
5. Wider Adaptability: Developing varieties that can survive in diverse climatic conditions.
6. Desirable Agronomic Characteristics: Developing tall crops for fodder (more food for animals) and dwarf crops for cereals (less nutrient consumption). - Compare and contrast the use of manure and fertilizers in agriculture. Discuss the long-term impact of each on soil fertility.
Answer:Manure Fertilizers Natural, prepared from decomposition of animal/plant waste. Chemical, commercially prepared in factories. Rich in organic matter (humus) but low in specific nutrients. No organic matter, but very rich in N, P, K. Improves soil structure and water-holding capacity. Does not improve soil structure; can damage it over time. Long-term Impact: Manure improves soil health continuously. Fertilizers give short-term high yields but, if used excessively, kill beneficial soil microbes and reduce soil fertility, eventually turning the land barren.
- What is animal husbandry? Describe the key management practices required for successful cattle farming, including shelter, food, and disease prevention.
Answer:
Animal Husbandry: The scientific management of animal livestock (feeding, breeding, and disease control) to obtain milk, meat, or labor.
Management Practices:
1. Shelter: Cattle need well-ventilated sheds with sloping floors to keep them dry and clean. They must be protected from rain, heat, and cold.
2. Food: Diet consists of Roughage (fiber like grass/hay) and Concentrates (protein/nutrient-rich grains). Balanced rations containing micronutrients promote high milk yield.
3. Disease Prevention: Cattle suffer from parasites (internal worms, external lice/ticks) and viral/bacterial diseases. Regular vaccinations are crucial to protect them from fatal diseases. - Explain the three main ways crops can be damaged by pests and diseases. Describe two chemical and two biological methods of crop protection.
Answer:
Modes of Attack:
1. Chewing/Cutting roots, stems, and leaves.
2. Sucking cell sap from plant parts.
3. Boring (drilling) into stems and fruits.
Chemical Methods:
1. Pesticides/Insecticides: Spraying chemicals like Malathion to kill insects.
2. Weedicides: Spraying chemicals to kill unwanted weeds.
Biological/Preventive Methods:
1. Resistant Varieties: Using seeds genetically modified to resist pests.
2. Summer Ploughing: Ploughing fields deep in summer to expose pest eggs/larvae to the intense heat of the sun, killing them naturally. - What are the advantages of composite fish culture? Name at least three species of fish used in such a system and explain how their different feeding habits help maximize the fish yield from the pond.
Answer:
Advantages: It allows intensive farming in a single pond, ensures no food is wasted, and results in a very high yield of fish.
Species and Habits:
1. Catla: Feeds on the surface (Zoo-plankton).
2. Rohu: Feeds in the middle zone of the pond (Algae).
3. Mrigal / Common Carp: Feeds at the bottom (Weeds and waste).
By selecting these specific fish, they do not compete with each other for food, utilizing all available resources in the pond efficiently.