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Chapter 12 Improvement In Food Resources
Food is essential for all living organisms, providing the necessary proteins, carbohydrates, fats, vitamins, and minerals for development, growth, and health. Our primary sources of food are plants (through agriculture) and animals (through animal husbandry).
India, with its large and growing population (over one billion people), faces a significant challenge in meeting its food demands. The amount of cultivable land is limited, so simply increasing the area under cultivation is not a viable long-term solution. Therefore, it is critical to improve the efficiency of food production from both crops and livestock. While past efforts like the Green Revolution (increased grain production) and White Revolution (increased milk production) have helped, they have often relied on intensive use of natural resources, raising concerns about environmental degradation and sustainability.
Sustainable practices in agriculture and animal husbandry are necessary to increase food production without harming the environment or depleting natural resources. Furthermore, ensuring food security requires not only increased availability but also access to food, which means addressing issues like poverty and farmers' income. Integrated farming practices that combine agriculture with livestock, poultry, fisheries, or bee-keeping can provide sustained livelihoods and improve overall yield.
The key question is: how can we scientifically manage and improve the yields of crops and livestock?
Improvement in Crop Yields
Crops provide essential nutrients for human survival:
- **Cereals** (wheat, rice, maize, millets, sorghum): Primary source of **carbohydrates** for energy.
- **Pulses** (gram, pea, black gram, green gram, pigeon pea, lentil): Rich source of **proteins**.
- **Oil seeds** (soyabean, ground nut, sesame, castor, mustard, linseed, sunflower): Provide necessary **fats**.
- **Vegetables, Spices, Fruits:** Supply a wide range of **vitamins and minerals**, along with small amounts of other nutrients.
Besides food crops, **fodder crops** (berseem, oats, sudan grass) are cultivated specifically to feed livestock.
Crops are grown based on seasonal and climatic conditions. **Kharif crops** are grown during the rainy season (June-October), such as paddy, soyabean, maize, cotton, and pulses like arhar, moong, urad. **Rabi crops** are grown in the winter season (November-April), including wheat, gram, peas, mustard, and linseed.
India has seen a substantial increase in food grain production since 1952, with only a modest increase in cultivated land area. This has been achieved through improvements in farming practices, which can be broadly divided into three categories aimed at increasing crop yields:
- **Crop Variety Improvement:** Developing better varieties of crops.
- **Crop Production Management:** Optimizing farming practices to improve yield.
- **Crop Protection Management:** Protecting crops from pests, diseases, and storage losses.
Crop Variety Improvement
Selecting and developing crop varieties with desirable characteristics is fundamental to increasing yield. This involves creating new varieties or strains that offer advantages such as:
- **Higher Yield:** Increasing the amount of crop produced per unit area (acre).
- **Improved Quality:** Enhancing specific quality traits depending on the crop, e.g., baking quality in wheat, protein content in pulses, oil quality in oilseeds, or preservation quality in fruits/vegetables.
- **Biotic and Abiotic Resistance:** Developing varieties that can withstand challenges from living organisms (**biotic stresses** like diseases, insects, nematodes) and environmental conditions (**abiotic stresses** like drought, salinity, waterlogging, heat, cold, frost).
- **Change in Maturity Duration:** Selecting varieties that mature faster or have uniform maturity. Shorter duration allows for growing multiple crops per year, reducing costs. Uniform maturity simplifies harvesting and reduces losses.
- **Wider Adaptability:** Creating varieties that can grow successfully in diverse climatic and environmental conditions, thus stabilizing production across different regions.
- **Desirable Agronomic Characteristics:** Breeding for traits that make cultivation more efficient or productive based on the crop's use. For instance, tallness and branching are good for fodder crops, while dwarfness is preferred in cereals to minimize nutrient consumption and improve lodging resistance.
New crop varieties with these traits are developed through breeding techniques, primarily **hybridisation**. Hybridisation involves crossing genetically different plants to combine desirable traits from both parents. This can be done between different varieties (intervarietal), different species of the same genus (interspecific), or even between different genera (intergeneric). Another method is creating **genetically modified crops (GM crops)** by introducing a gene that provides a desired characteristic, like pest resistance.
For new varieties to be successful, they must produce high yields under the diverse conditions faced by farmers and provide high-quality seeds that germinate reliably.
Question 1. How do biotic and abiotic factors affect crop production?
Answer:
Biotic and abiotic factors negatively affect crop production by causing stress and reducing yields. **Biotic factors** include diseases caused by pathogens (bacteria, fungi, viruses), damage from insect pests, and harm from nematodes. These can weaken or destroy plants, reduce crop quality, and decrease marketable yield. **Abiotic factors** are environmental conditions like drought (lack of water), salinity (high salt content in soil/water), waterlogging (excess water saturating the soil), heat, cold, and frost. These stresses can damage plant tissues, disrupt physiological processes, and lead to reduced growth or crop failure.
Question 2. What are the desirable agronomic characteristics for crop improvements?
Answer:
Desirable agronomic characteristics for crop improvements include:
- Higher yield per acre.
- Improved quality of the crop product (e.g., protein content, oil content, baking quality).
- Resistance to biotic stresses (diseases, insects, nematodes).
- Tolerance to abiotic stresses (drought, salinity, heat, cold).
- Shorter maturity duration or uniform maturity.
- Wider adaptability to different environmental conditions.
- Specific traits like dwarfness in cereals (for efficient nutrient use and reduced lodging) or tallness/branching in fodder crops (for increased biomass).
Crop Production Management
Managing crop production practices effectively is crucial for increasing yields. Farming practices vary widely depending on factors like land size, financial resources, and access to technology and information. Higher financial inputs generally correlate with higher yields, but sustainable and efficient low-cost methods are also important.
Nutrient Management
Plants, like animals, require essential nutrients for growth and health. These nutrients are obtained from air, water, and soil. Air provides carbon and oxygen, water provides hydrogen and oxygen, and soil provides thirteen other essential nutrients.
Nutrients required in **large quantities** are called **macro-nutrients** (e.g., nitrogen, phosphorus, potassium, calcium, magnesium, sulphur). Those required in **small quantities** are called **micro-nutrients** (e.g., iron, manganese, boron, zinc, copper, molybdenum, chlorine).
| Source | Nutrients |
|---|---|
| Air | Carbon, Oxygen |
| Water | Hydrogen, Oxygen |
| Soil (Macronutrients) | Nitrogen, Phosphorus, Potassium, Calcium, Magnesium, Sulphur |
| Soil (Micronutrients) | Iron, Manganese, Boron, Zinc, Copper, Molybdenum, Chlorine |
Deficiencies in these nutrients can negatively impact plant growth, reproduction, and resistance to diseases. To enhance yield, soil fertility must be maintained by replenishing nutrients, typically through the use of manure and fertilizers.
Manure
**Manure** is a natural substance produced by the decomposition of animal excreta (like cow dung) and plant waste. It is rich in **organic matter** and provides nutrients to the soil in small quantities. Manure is environmentally friendly as it utilizes biological waste and helps recycle farm materials.
Advantages of manure:
- Enriches soil with nutrients and organic matter.
- Improves soil structure, increasing water-holding capacity in sandy soils and aiding drainage in clayey soils.
- Provides long-term benefits to soil fertility and health.
- Does not cause pollution like excessive fertilizers.
- Supports soil micro-organisms.
Types of manure based on material used:
- **Compost:** Formed by the decomposition of farm waste (livestock excreta, vegetable waste, domestic waste, etc.) in pits.
- **Vermi-compost:** Compost prepared using earthworms to speed up the decomposition process.
- **Green manure:** Growing specific plants (like sun hemp or guar) and then ploughing them into the soil before sowing the main crop. These plants decompose, enriching the soil with nitrogen and phosphorus.
Fertilizers
**Fertilizers** are commercially produced plant nutrients, primarily supplying nitrogen (N), phosphorus (P), and potassium (K). They are concentrated sources of nutrients and promote vigorous vegetative growth (leaves, stems, flowers), contributing to high yields in high-cost farming.
However, fertilizers require careful application (correct dose, time, and method) for efficient uptake by plants. Excessive or improper use of fertilizers can have negative consequences:
- **Water pollution:** Excess fertilizers not absorbed by plants can leach into water bodies.
- **Soil degradation:** Continuous use can reduce soil fertility by depleting organic matter and harming beneficial soil micro-organisms.
Balancing the use of fertilizers for short-term yield boosts with the long-term benefits of manure for soil health is important for sustainable agriculture.
Question 1. Compare the use of manure and fertilizers in maintaining soil fertility.
Answer:
| Feature | Manure | Fertilizers |
|---|---|---|
| Nature | Natural organic material. | Commercial inorganic compounds. |
| Nutrient Content | Provides small amounts of nutrients, rich in organic matter. | Provides specific nutrients (N, P, K) in concentrated form, low in organic matter. |
| Soil Benefits | Improves soil structure (water retention, drainage), adds organic matter, supports micro-organisms. | Primarily adds specific nutrients, does not improve soil structure significantly, can harm micro-organisms over time. |
| Environmental Impact | Environmentally friendly, recycles waste. | Excess use can cause water pollution (eutrophication). |
| Absorption Rate | Nutrients released slowly upon decomposition. | Nutrients readily soluble and quickly available to plants. |
| Cost | Generally cheaper, can be produced on farm. | Commercially produced, more expensive. |
Organic Farming
**Organic farming** is a holistic farming system that minimizes or avoids the use of synthetic chemicals (fertilizers, herbicides, pesticides) and antibiotics. It focuses on using organic inputs and ecological practices to maintain soil health and biodiversity.
Key aspects of organic farming include:
- Use of organic manures and compost.
- Recycling farm wastes.
- Using bio-agents like blue-green algae as bio-fertilizers or neem/turmeric as bio-pesticides.
- Employing healthy cropping systems like mixed cropping, inter-cropping, and crop rotation to manage pests, weeds, and diseases naturally and improve nutrient use efficiency.
Irrigation
Reliable water supply is crucial for high crop yields, especially in rain-fed areas vulnerable to drought. Various irrigation systems are used in India to supplement rainfall:
- **Wells:** Dug wells (collect water from shallow sources) and tube wells (tap deeper groundwater). Water is lifted using pumps.
- **Canals:** Extensive systems drawing water from rivers or reservoirs, distributed through main canals and branches to fields.
- **River Lift Systems:** Water is directly pumped from rivers to irrigate nearby areas where canal flow is insufficient.
- **Tanks:** Small reservoirs collecting rainwater run-off from smaller catchment areas.
Modern initiatives also focus on **rainwater harvesting** and **watershed management**, including building small check-dams. These structures prevent rainwater from flowing away, reduce soil erosion, and increase groundwater levels, making more water available for agriculture.
Cropping Patterns
Different strategies for arranging and timing the cultivation of crops can maximize land use and reduce risks.
- **Mixed Cropping:** Growing **two or more crops simultaneously** on the **same piece of land**. Examples: wheat + gram, groundnut + sunflower.
- Advantage: Reduces the risk of complete crop failure and provides some yield insurance.
- **Inter-cropping:** Growing **two or more crops simultaneously** in a **definite row pattern** on the same field. Examples: few rows of one crop alternating with a few rows of another, like soyabean + maize, bajra + cowpea.
- Advantage: Better utilization of nutrients if crops have different nutrient requirements. Helps prevent pests and diseases from spreading throughout one crop. Can give better combined yields.
- **Crop Rotation:** Growing **different crops on the same piece of land in a pre-planned sequence**. The choice of the next crop depends on factors like the previous crop, soil conditions, and irrigation availability.
- Advantage: Helps restore soil nutrients if leguminous crops (which fix nitrogen) are included. Breaks pest and disease cycles. Can allow for growing multiple crops per year if planned properly.
Question 1. Which of the following conditions will give the most benefits? Why?
(a) Farmers use high-quality seeds, do not adopt irrigation or use fertilizers.
(b) Farmers use ordinary seeds, adopt irrigation and use fertilizer.
(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.
Answer:
Condition **(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures** will give the most benefits.
Here's why:
- Using **high-quality seeds** (as in a and c) provides the genetic potential for high yields, disease resistance, etc.
- Adopting **irrigation** (as in b and c) ensures that crops receive sufficient water at critical growth stages, reducing dependence on unpredictable rainfall and preventing water stress, which is essential for realizing the potential of good seeds and nutrients.
- Using **fertilizers** (as in b and c) provides necessary nutrients for vigorous plant growth and high productivity, especially with high-yielding varieties.
- Implementing **crop protection measures** (only in c) safeguards the crops from yield losses caused by weeds, pests, and diseases, which can significantly reduce the harvest even if all other conditions are favourable.
Condition (a) has good seeds but lacks essential water and nutrients, making high yields unlikely. Condition (b) provides water and nutrients but uses ordinary seeds (limiting genetic potential) and lacks protection, leaving the crop vulnerable. Only condition (c) combines all the factors necessary for maximizing crop yield and ensuring a successful harvest.
Crop Protection Management
Even with improved varieties and optimal production practices, crops can suffer significant losses from **weeds, insect pests, and diseases**. Effective crop protection management is essential throughout the growing season and during storage.
- **Weeds:** Unwanted plants that grow in cultivated fields (e.g., Xanthium, Parthenium, Cyperinus rotundus). They compete with crop plants for sunlight, nutrients, space, and water, reducing crop growth and yield. Removing weeds, especially in the early growth stages, is vital.
- **Insect Pests:** Insects that damage crops by cutting roots, stems, or leaves; sucking cell sap; or boring into stems and fruits. This weakens plants and reduces yield.
- **Diseases:** Caused by pathogens like bacteria, fungi, and viruses. These can be transmitted through soil, water, or air.
Control methods for weeds, pests, and diseases:
- **Pesticides:** Chemical control using herbicides (kill weeds), insecticides (kill insects), and fungicides (kill fungi). Applied by spraying or treating seeds/soil.
- Drawback: Excessive use is poisonous, can harm beneficial organisms, and causes environmental pollution.
- **Mechanical Removal:** Physically removing weeds (e.g., hand-weeding).
- **Preventive Methods:** Practices that minimize pest/weed/disease incidence. These include:
- Proper seed bed preparation.
- Timely sowing of crops.
- Using resistant crop varieties (developed through breeding).
- Practicing intercropping and crop rotation (disrupts pest/disease cycles).
- Summer ploughing (deep ploughing in summer exposes and kills pests and weeds).
- **Biological Control:** Using natural enemies or beneficial organisms to control pests and diseases (e.g., certain insects that feed on pests).
Preventive and biological control methods are generally preferred over chemical pesticides due to environmental and health concerns.
Storage Of Grains
Significant losses can occur after harvesting if grains are not stored properly. Factors causing storage losses include:
- **Biotic factors:** Living organisms like insects, rodents, fungi (moulds), mites, and bacteria.
- **Abiotic factors:** Non-living conditions, primarily inappropriate moisture levels and temperature.
These factors can lead to degradation in quality, weight loss, reduced germination capacity, discolouration, and overall poor marketability of the stored produce.
Proper storage management involves preventive and control measures applied before and during storage:
- Strict cleaning of the grain before storage.
- Proper drying of the grain (first in sunlight, then in shade) to reduce moisture content.
- Maintaining hygienic conditions in warehouses.
- Fumigation using chemicals (pesticides) to kill pests in the storage area or on the grain.
Systematic management of warehouses is essential to minimize losses and maintain the quality of stored grains for future use.
Question 1. Why should preventive measures and biological control methods be preferred for protecting crops?
Answer:
Preventive measures and biological control methods should be preferred for protecting crops over chemical pesticides because they are more sustainable and environmentally friendly. Chemical pesticides can cause harm to human health, poison beneficial organisms (like pollinators and natural predators of pests), contaminate soil and water, and lead to the development of pesticide resistance in pests. Preventive and biological methods, on the other hand, work in harmony with the ecosystem, minimize the use of toxic substances, reduce pollution, and promote biodiversity and long-term soil health.
Question 2. What factors may be responsible for losses of grains during storage?
Answer:
Losses of grains during storage can be caused by:
- **Biotic Factors:** Insects, rodents (rats, mice), fungi (causing mould and spoilage), mites, and bacteria.
- **Abiotic Factors:** Inappropriate moisture content (high humidity encourages microbial and insect growth) and unsuitable temperature (warm temperatures increase pest activity).
These factors lead to spoilage, consumption, degradation, and reduced quality of the stored grains.
Animal Husbandry
**Animal husbandry** is the scientific management of animal livestock, covering aspects like feeding, breeding, and disease control. It includes farming of cattle, goats, sheep, poultry, and fish. With increasing population and living standards, the demand for animal products like milk, eggs, and meat is rising, necessitating improvements in livestock production while also considering humane treatment of animals.
Cattle Farming
**Cattle husbandry** is done for two main purposes: obtaining **milk** (from milch animals or dairy animals, typically females) and obtaining **draught labour** for agricultural work (tilling, irrigation, carting) from draught animals. Indian cattle species include cows (Bos indicus) and buffaloes (Bos bubalis).
Improving milk production involves increasing the duration of the **lactation period** (the period of milk production after calving). Cross-breeding is a common method used to combine desirable traits from different breeds. For example, exotic breeds (Jersey, Brown Swiss) known for long lactation periods can be cross-bred with local breeds (Red Sindhi, Sahiwal) that are highly resistant to diseases. This results in hybrid animals with both qualities.
Good cattle farming practices include:
- **Proper Shelter:** Well-ventilated sheds to protect animals from weather extremes (rain, heat, cold). Floors should be sloping for drainage and hygiene.
- **Regular Cleaning:** Maintaining clean conditions in sheds and regular brushing of animals.
- **Balanced Feeding:** Providing food that meets two types of requirements:
- Maintenance requirement: Food for healthy living.
- Milk production requirement: Additional food needed during lactation.
Animal feed includes **roughage** (high fibre, e.g., fodder) and **concentrates** (low fibre, high protein and nutrients, e.g., grains, oilcakes). Balanced rations containing all nutrients are crucial, sometimes supplemented with micronutrient additives to improve health and milk yield.
- **Disease Control:** Preventing and treating diseases is vital as they reduce milk production and can cause death. Diseases are caused by parasites (external like ticks, internal like worms/flukes), bacteria, and viruses.
- External parasites cause skin diseases; internal parasites affect organs.
- Infectious diseases are controlled by maintaining hygiene, using disinfectants, and especially through **vaccination** against major viral and bacterial diseases.
Question 1. Which method is commonly used for improving cattle breeds and why?
Answer:
The method commonly used for improving cattle breeds is **cross-breeding**. This involves mating animals from different breeds (e.g., local and exotic breeds) that possess desirable traits. The aim is to combine these traits in the offspring, such as the long lactation period of exotic breeds with the disease resistance of local breeds. This results in improved hybrid varieties that are more productive and better adapted to local conditions.
Poultry Farming
**Poultry farming** focuses on raising domestic fowl (chickens, ducks, turkeys, etc.) for **egg production** (layers) and **chicken meat** (broilers). Variety improvement programmes aim to develop breeds with desirable traits for these purposes, often by cross-breeding Indian (indigenous, e.g., Aseel) and foreign (exotic, e.g., Leghorn) breeds.
Desirable traits for poultry breed improvement:
- Increased number and quality of chicks.
- Development of dwarf broiler parents for commercial meat production (reduces feed cost).
- Improved adaptation and tolerance to high temperatures (important in hot climates).
- Low maintenance requirements.
- Smaller size for egg layers with efficient utilization of cheaper, high-fibre diets from agricultural by-products.
Management of layers (for eggs) and broilers (for meat) differs:
- **Layers:** Managed for egg production. Require sufficient space, proper lighting (duration affects egg laying), and layers' mash feed.
- **Broilers:** Managed for rapid growth to produce meat. Fed with protein-rich and fat-adequate diets supplemented with vitamins (especially A and K) for good growth rate and feed efficiency. Care is taken to maintain feathering, carcass quality, and minimize mortality.
Common good management practices essential for both layers and broilers include maintaining proper temperature and hygienic conditions in housing (cleaning, sanitation, disinfectants), providing adequate poultry feed, and preventing and controlling diseases and pests through vaccination and hygiene.
Question 1. What management practices are common in dairy and poultry farming?
Answer:
Common management practices in both dairy farming (cattle) and poultry farming (fowl) include:
- **Proper Feeding:** Providing a balanced and nutritious diet suitable for the animal's age and purpose (milk production, meat production, egg production, maintenance).
- **Hygiene and Sanitation:** Maintaining clean shelters, food, and water to prevent the spread of diseases.
- **Proper Shelter:** Providing housing that protects animals from harsh weather conditions (rain, heat, cold) and allows for adequate ventilation.
- **Disease Prevention and Control:** Regular health check-ups, vaccination programmes to prevent infectious diseases, and isolation/treatment of sick animals.
- **Breeding Programs:** Implementing planned breeding strategies to improve the traits of the livestock/poultry varieties.
(Any three or four of the above are common practices).
Question 2. What are the differences between broilers and layers and in their management?
Answer:
Broilers and layers are types of poultry raised for different purposes, leading to differences in their characteristics and management:
| Feature | Broilers | Layers |
|---|---|---|
| Purpose | Raised for meat production. | Raised for egg production. |
| Growth Rate | Fast growth rate is desired. | Rapid growth is not the primary goal; focus is on egg laying capacity. |
| Life Span on Farm | Relatively short (raised to market weight quickly). | Kept for longer periods (until their egg-laying rate declines). |
| Diet | Protein-rich diet with adequate fat and high levels of vitamins (A, K) to promote rapid growth. | Diet formulated to support egg production and maintenance, often utilizes cheaper fibrous feeds. |
| Housing/Lighting | Management focuses on promoting fast weight gain and efficiency. Lighting may be adjusted to support growth. | Management focuses on maximizing egg production rate. Lighting duration (photoperiod) is crucial for stimulating egg laying. |
| Ideal Body Size | Desired for good meat yield. | Smaller body size is often preferred (low maintenance). |
Question 1. Discuss the implications of the following statement:
“It is interesting to note that poultry is India’s most efficient converter of low fibre food stuff (which is unfit for human consumption) into highly nutritious animal protein food.”
Answer:
The statement highlights poultry's remarkable efficiency in converting certain types of agricultural by-products and low-quality grains (which humans cannot digest well due to their high fibre content) into valuable and easily digestible animal protein (eggs and meat). The implications are:
- **Resource Efficiency:** Poultry farming makes productive use of resources that would otherwise go to waste, increasing the overall efficiency of the food system.
- **Nutritional Security:** By transforming less useful plant material into high-quality protein, poultry contribute significantly to improving protein availability in the human diet, addressing nutritional deficiencies.
- **Economic Benefit:** This efficiency can make poultry farming economically viable, especially for farmers with access to such low-fibre feedstuffs, contributing to livelihoods.
- **Reduced Competition with Human Food:** Unlike livestock that might consume grains suitable for direct human consumption, poultry can thrive on feed that humans cannot effectively utilize, minimizing competition for food resources.
In essence, poultry act as biological converters, upcycling low-value feed into high-value food, making them a valuable component of sustainable food production systems.
Fish Production
**Fish** is a vital and often cheap source of animal protein. Fish production includes capturing fish from natural water bodies (**capture fishing**) and intentionally raising fish in controlled environments (**culture fishery** or aquaculture). Fish resources can be marine (seawater) or inland (freshwater or brackish water).
- **Marine Fisheries:** Involves capturing fish from oceans and seas. Popular varieties include pomphret, mackerel, tuna, sardines, and Bombay duck. Modern techniques like using satellites and echo-sounders help locate large groups (schools) of fish. Due to depletion of natural stocks, **mariculture** (culture fishery in seawater) is increasingly practiced for high-value marine fish (mullets, bhetki, pearl spots), shellfish (prawns, mussels, oysters), and seaweed. Oysters are also cultivated for pearls.
- **Inland Fisheries:** Includes capture fishing and aquaculture in freshwater resources (canals, ponds, reservoirs, rivers) and **brackish water** resources (estuaries, lagoons) where freshwater and seawater mix. Aquaculture is the primary source of inland fish production due to limited yield from capture fishing in these areas.
Intensive inland fish farming often uses **composite fish culture systems**. In this system, multiple fish species (e.g., 5 or 6) are grown together in a single pond. The species are carefully selected based on their feeding habits to avoid competition and ensure that all available food resources in the pond (surface, middle layer, bottom) are utilized. Examples of species used include Catla (surface feeders), Rohu (middle-zone feeders), Mrigal and Common Carp (bottom feeders), and Grass Carp (weed feeders).
A major challenge in composite fish culture has been the lack of availability of pure fish seed, as many local fish breed only during monsoon, and wild-caught seed may be mixed with other species. This problem has been addressed by inducing breeding in fish in ponds using **hormonal stimulation**, which ensures a supply of pure fish seed in desired quantities.
Question 1. How are fish obtained?
Answer:
Fish are obtained in two main ways:
- **Capture Fishing:** Obtaining fish from natural resources (oceans, rivers, lakes) by using fishing nets and boats.
- **Culture Fishery (Aquaculture):** Intentionally farming and raising fish in controlled environments such as ponds, tanks, or cages in marine or freshwater bodies.
Question 2. What are the advantages of composite fish culture?
Answer:
The advantages of composite fish culture are:
- **Increased Yield:** By combining multiple species with different feeding habits, the food resources available in all parts of the pond are utilized efficiently, leading to a higher overall fish yield from the same pond area compared to farming a single species.
- **Reduced Competition:** Careful selection of species minimizes competition for food among the different fish in the pond.
- **Efficient Resource Use:** Different ecological niches within the pond are utilized, making the system more efficient.
Bee-Keeping
**Bee-keeping** (apiculture) is the practice of maintaining colonies of honey bees in artificial hives for the production of **honey** and **beeswax**. It is a low-investment activity that can serve as an additional source of income for farmers. Beeswax has various uses, including in medicinal preparations.
Local Indian bee varieties used for honey production include Apis cerana indica (Indian bee), A. dorsata (rock bee), and A. florae (little bee). The **Italian bee variety, Apis mellifera**, is widely used for commercial honey production due to its desirable characteristics:
- High honey collection capacity.
- Less prone to stinging.
- Stays in the beehive for long periods.
- Good breeding rate.
For commercial production, bee farms called **apiaries** are established, where multiple beehives are kept.
The **quality and taste of honey** are influenced by the **pasturage**, which refers to the types of flowers and plants available to the bees for collecting nectar and pollen. Abundant and diverse pasturage leads to higher quality and greater quantity of honey.
Question 1. What are the desirable characters of bee varieties suitable for honey production?
Answer:
Desirable characters of bee varieties suitable for honey production include:
- High honey collection capacity.
- Being less sting-prone.
- Ability to stay in the beehive for long periods (less swarming).
- Good breeding rate.
- Resistance to diseases.
Question 2. What is pasturage and how is it related to honey production?
Answer:
**Pasturage** refers to the flowers and plants available to honey bees for the collection of nectar and pollen. It essentially represents the availability of food sources for bees.
Pasturage is directly related to honey production in several ways: the **quantity** of pasturage available determines the amount of nectar and pollen bees can collect, which in turn affects the overall quantity of honey produced by the colony. The **kind** of flowers in the pasturage determines the **quality and taste** of the honey.
Intext Questions
Page No. 141
Question 1. What do we get from cereals, pulses, fruits and vegetables?
Answer:
Page No. 142
Question 1. How do biotic and abiotic factors affect crop production?
Answer:
Question 2. What are the desirable agronomic characteristics for crop improvements?
Answer:
Page No. 143
Question 1. What are macro-nutrients and why are they called macronutrients?
Answer:
Question 2. How do plants get nutrients?
Answer:
Page No. 144
Question 1. Compare the use of manure and fertilizers in maintaining soil fertility.
Answer:
Page No. 145
Question 1. Which of the following conditions will give the most benefits? Why?
(a) Farmers use high-quality seeds, do not adopt irrigation or use fertilizers.
(b) Farmers use ordinary seeds, adopt irrigation and use fertilizer.
(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.
Answer:
Page No. 146
Question 1. Why should preventive measures and biological control methods be preferred for protecting crops?
Answer:
Question 2. What factors may be responsible for losses of grains during storage?
Answer:
Page No. 147
Question 1. Which method is commonly used for improving cattle breeds and why?
Answer:
Page No. 148
Question 1. Discuss the implications of the following statement:
“It is interesting to note that poultry is India’s most efficient converter of low fibre food stuff (which is unfit for human consumption) into highly nutritious animal protein food.”
Answer:
Question 1. What management practices are common in dairy and poultry farming?
Answer:
Question 2. What are the differences between broilers and layers and in their management?
Answer:
Page No. 150
Question 1. How are fish obtained?
Answer:
Question 2. What are the advantages of composite fish culture?
Answer:
Question 1. What are the desirable characters of bee varieties suitable for honey production?
Answer:
Question 2. What is pasturage and how is it related to honey production?
Answer:
Exercises
Question 1. Explain any one method of crop production which ensures high yield.
Answer:
Question 2. Why are manure and fertilizers used in fields?
Answer:
Question 3. What are the advantages of inter-cropping and crop rotation?
Answer:
Question 4. What is genetic manipulation? How is it useful in agricultural practices?
Answer:
Question 5. How do storage grain losses occur?
Answer:
Question 6. How do good animal husbandry practices benefit farmers?
Answer:
Question 7. What are the benefits of cattle farming?
Answer:
Question 8. For increasing production, what is common in poultry, fisheries and bee-keeping?
Answer:
Question 9. How do you differentiate between capture fishing, mariculture and aquaculture?
Answer: