Chapter 9: Strategies for Enhancement in Food Production

Q1. What is the difference between inbreeding and outbreeding?

Solution

Inbreeding: Mating between closely related individuals, increases homozygosity
Outbreeding: Mating between unrelated individuals, increases heterozygosity and hybrid vigor

Q2. What is meant by single cell protein?

Solution

Single cell protein (SCP) refers to edible proteins extracted from pure or mixed cultures of microorganisms (algae, fungi, yeast, bacteria) grown on agricultural wastes, used as protein-rich food supplements.

Q3. What are the objectives of plant breeding?

Solution

1. Increased crop yield
2. Improved quality
3. Resistance to diseases and pests
4. Tolerance to environmental stress
5. Shorter maturity period

Q4. What is the Green Revolution? Name two achievements.

Solution

Achievements: (1) Introduction of semi-dwarf wheat and rice varieties (2) India became self-sufficient in food grain production

Q5. What is animal husbandry? What are its components?

Solution

Components: (1) Cattle farming (milk and draught) (2) Poultry farming (eggs and meat) (3) Fish farming (pisciculture) (4) Bee-keeping (apiculture) (5) Silk production (sericulture)

Q6. What is tissue culture? What are its applications?

Solution

Applications: (1) Micropropagation - rapid multiplication (2) Virus-free plant production (3) Somatic hybridization (4) Production of secondary metabolites (5) Conservation of endangered species

Q7. What is biofortification?

Solution

Importance: (1) Addresses micronutrient deficiency (2) Example: Golden Rice (Vitamin A) (3) Iron-rich wheat (4) Protein-rich beans (5) Cost-effective for developing countries

Q8. What are the methods used in plant breeding?

Solution

1. Selection (mass, pure-line)
2. Hybridization (intraspecific, interspecific)
3. Mutation breeding
4. Polyploidy breeding
5. Molecular breeding (marker-assisted selection)
6. Genetic engineering (transgenic crops)

Q9. What is apiculture? What are the products from honeybees?

Solution

Products: (1) Honey (2) Beeswax (3) Royal jelly (4) Propolis (5) Bee venom

Q10. What is pisciculture? What are its types?

Solution

Extensive: Natural water bodies, low input
Semi-intensive: Managed ponds, moderate input
Intensive: High stocking density, high feed input
Important species: Carp, Catla, Rohu, Hilsa

Q11. What is hybrid vigor (heterosis)?

Solution

Uses: (1) Cross-breeding cattle for milk (2) Poultry breeding (3) Increases growth rate, milk yield (4) Example: Hisardale sheep

Q12. What are the benefits of cross-breeding in animal husbandry?

Solution

1. Combines desirable traits of two breeds
2. Increases milk production
3. Improves disease resistance
4. Enhances growth rate
Example: Sahiwal x Holstein Friesian

Q13. What are the challenges in food production?

Solution

1. Increasing population and food demand
2. Loss of agricultural land
3. Water scarcity
4. Climate change effects
5. Pests and diseases
6. Post-harvest losses

Q14. What is somatic hybridization?

Solution

Uses: (1) Combines traits from different species (2) Overcomes sexual incompatibility (3) Example: Pomato (Potato + Tomato) (4) Creates novel crop varieties

Q15. What are the steps in development of a new crop variety?

Solution

1. Collection of germplasm
2. Evaluation and selection of parents
3. Hybridization
4. Selection of superior plants
5. Testing and release
6. Seed production and distribution

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