UPSC Mains Answer PYQ 2023: Agriculture Paper 2 (Section- B) | Agriculture Optional Notes for UPSC PDF Download

Section - B

Q5: Answer the following questions in about 150 words each : (10x5=50)
(a) Write down the constraints of fruit processing industry in India.   (10 Marks)
Ans: 
Introduction: The fruit processing industry in India faces several challenges that hinder its growth and development.
1. Inadequate Infrastructure:

• Description: Insufficient processing units, cold storage facilities, and transportation networks lead to post-harvest losses.
• Example: Lack of modern processing plants in rural areas hampers efficient fruit processing.

2. Lack of Modern Technology:

• Description: Outdated processing methods and equipment limit the efficiency and quality of processed fruit products.
• Example: Limited adoption of advanced technologies like aseptic processing and packaging.

3. Seasonal Availability of Fruits:

• Description: Many fruits have a specific harvest season, leading to uneven raw material supply for processing units.
• Example: Mangoes are harvested mainly during the summer season, resulting in a concentrated supply.

4. Inconsistent Quality of Raw Materials:

• Description: Variability in fruit quality due to factors like weather conditions, pest damage, and harvesting practices.
• Example: Variations in sugar content of mangoes can affect the quality of mango pulp.

5. Lack of Market Linkages:

• Description: Difficulties in connecting processing units with markets, distributors, and retailers for efficient product distribution.
• Example: Difficulty in finding reliable buyers for processed fruit products.

6. Regulatory Challenges:

• Description: Compliance with various regulations and standards related to food safety, quality, and labeling can be complex and costly.
• Example: Adhering to FSSAI (Food Safety and Standards Authority of India) guidelines.

Conclusion: 
Addressing these constraints through investments in infrastructure, adoption of modern technology, and streamlined supply chain management is crucial for the growth and sustainability of the fruit processing industry in India

(b) Describe mentha cultivation with reference to varieties, soil and climate, nutrient management and processing.   (10 Marks)
Ans: 
Introduction: Mentha, commonly known as mint, is a highly aromatic herb with various culinary, medicinal, and industrial uses. Cultivation of mentha requires specific considerations.

Varieties:

• Peppermint (Mentha x piperita): Known for its high menthol content and strong aroma. Example: Black Mitcham.

• Spearmint (Mentha spicata): Has a milder aroma compared to peppermint. Example: Scotch Spearmint.

Soil and Climate:

• Soil: Well-drained loamy soils with a pH range of 6.0 to 7.5 are ideal for mentha cultivation.

• Climate: Mentha thrives in temperate climates with moderate rainfall and abundant sunlight.

Nutrient Management:

• Nitrogen (N): Essential for leafy growth and essential oil production. Apply balanced NPK fertilizers.

• Phosphorus (P): Promotes root development and flowering. Phosphorus-rich fertilizers are recommended.

• Potassium (K): Aids in oil synthesis and stress tolerance. Ensure adequate potassium levels.

Processing:

• Distillation of Essential Oil: The leaves of mentha are subjected to steam distillation to extract the essential oil, which is used in various industries like pharmaceuticals, flavorings, and aromatherapy.

Conclusion: 
Mentha cultivation can be a profitable venture if managed carefully, considering factors like variety selection, soil and climate conditions, nutrient management, and efficient processing of the harvested crop.

(c) Enlist the role of auxins in agriculture, with suitable examples.   (10 Marks)
Ans: 
Introduction: 
Auxins are a class of plant hormones that regulate various aspects of plant growth and development. Their role in agriculture is significant.

1. Stimulating Root Formation:

• Description: Auxins like Indole-3-butyric acid (IBA) are used in rooting powders to promote the formation of roots in cuttings.
• Example: Propagating plants like roses or tomatoes through stem cuttings.

2. Preventing Fruit Drop:

• Description: Application of auxins like naphthaleneacetic acid (NAA) can help prevent premature fruit drop.
• Example: Extending the retention period of fruit crops like apples.

3. Weed Control:

• Description: Synthetic auxins like 2,4-D are used as herbicides to control broadleaf weeds in agricultural fields.
• Example: 2,4-D is widely used to control weeds in cereal crops like wheat and corn.

4. Promoting Fruit Development:

• Description: Auxins play a role in stimulating fruit growth and development, especially in seedless varieties.
• Example: Inducing fruit set in seedless grapes using auxin treatments.

Conclusion: 
Auxins have diverse applications in agriculture, ranging from propagation of plants to controlling weed growth and enhancing fruit development. Understanding their role allows for targeted use in improving crop yield and quality.

(d) Briefly discuss Integrated Pest Management in cotton.   (10 Marks)
Ans: 
Introduction: 
IPM is an approach that combines various pest control methods to manage pests in an environmentally sustainable and economically viable manner.

1. Biological Control:

• Description: Introduction of natural predators like ladybugs and parasitic wasps to control cotton pests like aphids and bollworms.
• Example: Releasing predatory beetles to manage aphid populations.

2. Cultural Practices:

• Description: Crop rotation, sanitation, and planting trap crops to disrupt pest life cycles and reduce pest populations.
• Example: Planting marigolds alongside cotton to deter nematodes.

3. Resistant Varieties:

• Description: Planting cotton varieties with natural resistance or tolerance to specific pests, reducing the need for chemical control.
• Example: Planting Bt cotton varieties for resistance against bollworms.

4. Chemical Control (As a Last Resort):

• Description: Judicious use of pesticides based on monitoring and thresholds to prevent economic damage.
• Example: Applying insecticides when pest populations exceed economic thresholds.

5. Monitoring and Record-keeping:

• Description: Regular scouting for pests and their natural enemies, along with keeping records to track pest populations over time.
• Example: Using pheromone traps to monitor moth activity for bollworm control.

Conclusion: 
IPM strategies in cotton production aim to minimize the impact of pests while promoting sustainable and economically viable cotton cultivation. By integrating multiple approaches, growers can effectively manage pest populations while reducing reliance on chemical control methods.

(e) Briefly discuss the micronutrient deficiencies observed in children and women in India along with the diseases associated with them.   (10 Marks)
Ans: 
Introduction:
Micronutrient deficiencies are a significant public health concern in India, particularly among children and women, leading to various health issues.

1. Iron Deficiency:

• Description: Anemia due to inadequate iron intake leads to fatigue, weakness, and impaired cognitive development in children.
• Example: Iron-deficiency anemia is prevalent among young children and pregnant women in India.

2. Vitamin A Deficiency:

• Description: Impaired vision, weakened immunity, and increased susceptibility to infections.
• Example: Night blindness and increased vulnerability to infections in children.

3. Iodine Deficiency:

• Description: Causes goiter, mental retardation, and developmental abnormalities.
• Example: High prevalence of goiter in certain regions of India due to iodine-deficient soils and inadequate dietary intake.

4. Zinc Deficiency:

• Description: Impairs growth, immune function, and cognitive development in children.
• Example: Stunted growth and increased susceptibility to infections in zinc-deficient individuals.

5. Calcium Deficiency:

• Description: Weak bones, dental issues, and increased risk of osteoporosis.
• Example: Low bone density and increased risk of fractures in women with calcium deficiency.

Conclusion: 
Addressing micronutrient deficiencies requires targeted interventions, including dietary diversification, fortification of staple foods, supplementation, and public awareness campaigns. Ensuring adequate micronutrient intake is crucial for the overall health and well-being of children and women in India.

Q6:
(a) Describe the principles, components and strategies for Integrated Disease Management in crops. Write down its application in management of rice blast and bacterial blight of pomegranate.   (20 Marks)
Ans: 
Introduction: 
Integrated Disease Management (IDM) is an approach that combines various strategies to prevent, control, and manage plant diseases in an environmentally sustainable and economically viable manner.

Principles of IDM:

• Diversity of Approaches: Utilizing multiple methods, such as cultural practices, biological control, resistant varieties, and chemical control, to address disease problems.

• Ecosystem Approach: Considering the interactions between plants, pathogens, and their environment to develop holistic disease management strategies.

• Sustainable Practices: Emphasizing practices that minimize environmental impact and preserve natural resources.

Components of IDM:

• Cultural Practices: Crop rotation, proper spacing, sanitation, and timely irrigation to create an environment less conducive to pathogen growth.

• Biological Control: Introduction of natural enemies, like predatory insects or beneficial microorganisms, to suppress pathogen populations.

• Resistant Varieties: Utilizing plant varieties that possess natural resistance or tolerance to specific diseases.

• Chemical Control (As a Last Resort): Judicious use of pesticides based on monitoring and thresholds to prevent economic damage.

Strategies for IDM:

• Early Detection and Diagnosis: Regular scouting and monitoring to identify disease outbreaks early, allowing for timely intervention.

• Crop Rotation and Diversification: Alternating crops to disrupt disease cycles and reduce pathogen build-up in the soil.

• Use of Biocontrol Agents: Introducing beneficial organisms like predatory insects, parasitic nematodes, or antagonistic microorganisms.

Application in Rice Blast and Bacterial Blight of Pomegranate: 
1. Rice Blast:

• Resistant Varieties: Planting rice varieties with genetic resistance to blast.
• Fungicide Application: Using fungicides based on disease forecasting models.
• Cultural Practices: Proper water management and balanced fertilization to reduce disease incidence.

2. Bacterial Blight of Pomegranate:

• Sanitation: Pruning and removing infected plant parts to prevent disease spread.
• Copper-Based Sprays: Using copper-based fungicides for bacterial blight control.
• Resistant Varieties: Planting pomegranate varieties with some level of resistance.

Conclusion: 
IDM offers a comprehensive approach to managing plant diseases, emphasizing sustainability and integrated use of various strategies.

(b) Discuss the package of Guava cultivation with reference to soil and climate, propagation, varieties, disease management and bahar treatment.    (20 Marks)
Ans: 
Introduction:
Guava is a tropical fruit with high nutritional value. Successful cultivation requires attention to specific factors.

Soil and Climate:

• Soil: Well-drained loamy soils with a pH range of 4.5 to 8.2 are suitable for guava cultivation.

• Climate: Thrives in subtropical to tropical climates with a temperature range of 20-30°C. It is sensitive to frost.

Propagation:

• Propagation by Seeds: Generally not recommended due to genetic variability in seed-grown plants.

• Propagation by Cuttings: Most common method. Semi-hardwood cuttings with 15-20 cm length are used.

Varieties:

• Allahabad Safeda: Known for its sweet and aromatic fruits. It's a popular variety.

• L-49: Preferred for its pinkish flesh and good keeping quality.

Disease Management:

• Anthracnose Control: Application of fungicides like copper-based sprays during flowering and fruiting stages.

• Root Rot Management: Proper drainage and avoiding waterlogging are essential to prevent root rot.

Bahar Treatment: Controlled withholding of irrigation to induce uniform flowering.

Conclusion: 
Successful guava cultivation requires attention to factors like soil, climate, propagation methods, variety selection, disease management, and appropriate cultural practices.

(c) Briefly discuss round-the-year marigold cultivation with reference to varieties, sowing and transplanting, disease management and value-addition.    (10 Marks)
Ans: 
Introduction: 
Marigold is a popular ornamental flower known for its vibrant colors. Round-the-year cultivation can be achieved with proper planning.

Varieties:

• African Marigold (Tagetes erecta): Taller varieties with large, fully double flowers. Example: 'Antigua'.

• French Marigold (Tagetes patula): Compact plants with smaller, semi-double flowers. Example: 'Durango'.

Sowing and Transplanting:

• Nursery Preparation: Sow seeds in well-prepared seedbeds or trays with good drainage.

• Transplanting: After 4-6 weeks, transplant seedlings with 4-6 true leaves at a spacing of 30x30 cm.

Disease Management:

• Powdery Mildew Control: Application of sulfur-based fungicides and maintaining proper spacing for good air circulation.

• Nematode Management: Crop rotation with non-host plants and soil solarization.

Value-Addition:

• Drying marigold flowers for making potpourri, extracting essential oils, or using them in various craft applications.

Conclusion: 
Round-the-year marigold cultivation involves proper selection of varieties, timely sowing and transplanting, disease management, and exploring value-addition opportunities to maximize the economic returns from marigold cultivation.

Q7:
(a) Enlist various photosynthetic pigments. Give a detailed account of chlorophyll synthesis along with the enzymes involved in the process. Also mention the role of carotenoids in photosynthesis.    (20 Marks)
Ans: 
Introduction: 
Photosynthetic pigments are molecules that absorb specific wavelengths of light during photosynthesis, enabling plants to convert light energy into chemical energy. The main photosynthetic pigments are chlorophylls and carotenoids.

Various Photosynthetic Pigments:

• Chlorophyll a: It is the primary pigment responsible for capturing light energy in photosynthesis. It absorbs red and blue light and appears green.

• Chlorophyll b: This pigment complements chlorophyll a by absorbing light at slightly different wavelengths. It expands the range of light that can be utilized for photosynthesis.

• Carotenoids: These include carotenes (like beta-carotene) and xanthophylls. They absorb light in the blue and green regions and appear yellow, orange, or red. They play a crucial role in photoprotection.

Chlorophyll Synthesis:
1. Aminolevulinic Acid (ALA) Synthesis:

• ALA is the precursor molecule for chlorophyll synthesis.
• Enzyme: ALA synthase catalyzes the formation of ALA from glycine and succinyl-CoA.

2. Porphyrin Synthesis:

• ALA is converted into porphobilinogen through a series of enzymatic reactions.
• Enzymes: Various enzymes like porphobilinogen deaminase and uroporphyrinogen III synthase are involved.

3. Chlorophyll Precursor Formation:

• Porphobilinogen is converted into chlorophyllide, a precursor of chlorophyll.
• Enzymes: Ferrochelatase inserts iron into the chlorophyll molecule.

4. Chlorophyll Formation:

• Chlorophyllide is modified to form chlorophyll a and b.
• Enzymes: Chlorophyll synthase plays a key role in this final step.

Role of Carotenoids:

• Accessory Pigments: Carotenoids expand the range of light absorption, complementing the function of chlorophylls.

• Photoprotection: They dissipate excess light energy as heat, protecting plants from damage caused by excessive light intensity.

Conclusion: 
Photosynthetic pigments, especially chlorophylls and carotenoids, are crucial for capturing light energy in photosynthesis. The synthesis of chlorophyll involves multiple enzymatic steps, starting from ALA production to the formation of chlorophyll a and b. Carotenoids play a vital role in broadening the spectrum of light absorption and in photoprotection.

(b) List the reactions of Calvin Cycle and Hatch-Slack Cycle for CO2 fixation in plants along with enzymes involved.    (20 Marks)
Ans: 
Introduction: 
The Calvin Cycle and Hatch-Slack Cycle (C4 pathway) are two key processes involved in carbon fixation during photosynthesis.

Calvin Cycle Reactions:

• Carbon Fixation (RuBP Carboxylation): Enzyme: Rubisco (Ribulose-1,5-bisphosphate carboxylase/oxygenase) catalyzes the addition of CO2 to ribulose-1,5-bisphosphate (RuBP), forming two molecules of 3-phosphoglycerate (3-PGA).

• Reduction Phase: ATP and NADPH produced in the light reactions are utilized to convert 3-PGA into glyceraldehyde-3-phosphate (G3P).

• Regeneration of RuBP: Some G3P molecules are converted back into RuBP using ATP.

Hatch-Slack Cycle (C4 Pathway) Reactions:

• CO2 Fixation (Pep Carboxylation): Enzyme: Phosphoenolpyruvate carboxylase (PEP carboxylase) catalyzes the addition of CO2 to phosphoenolpyruvate (PEP) to form oxaloacetate (OAA).

• Decarboxylation (C4 Acid Decarboxylation): OAA is converted into malate, which releases CO2.

• Calvin Cycle (C3 Cycle): Malate is transported to the bundle sheath cells, where it releases CO2 for the Calvin Cycle.

Conclusion: 
The Calvin Cycle and Hatch-Slack Cycle are crucial processes for CO2 fixation in plants. The Calvin Cycle involves carbon fixation, reduction, and RuBP regeneration. In the Hatch-Slack Cycle, CO2 is initially fixed into a C4 compound (OAA) through PEP carboxylation, followed by decarboxylation and release of CO2 for the Calvin Cycle.

(c) Briefly discuss the pathways of carbohydrate metabolism in plants.    (10 Marks)
Ans: 
Introduction:
Carbohydrate metabolism in plants involves the synthesis (anabolism) and breakdown (catabolism) of carbohydrates for energy and structural components.

Pathways of Carbohydrate Metabolism:
1. Photosynthesis:

• Plants synthesize glucose and other sugars from CO2 and water in the presence of light, using chlorophyll pigments and enzymes.
• Location: Chloroplasts

2. Glycolysis:

• Glucose is broken down into two molecules of pyruvate, producing ATP and NADH.
• Location: Cytoplasm

3. Gluconeogenesis:

• Synthesis of glucose from non-carbohydrate precursors (like pyruvate, lactate, amino acids) during low glucose conditions.
• Location: Mostly in the liver and kidneys.

4. Glycogenolysis:

• Breakdown of glycogen into glucose units for energy release.
• Location: Liver and muscle cells.

5. Glycogenesis:

• Synthesis of glycogen from glucose for short-term energy storage.
• Location: Liver and muscle cells.

6. TCA Cycle (Citric Acid Cycle):

• Further breakdown of pyruvate into CO2, producing ATP, NADH, and FADH2.
• Location: Mitochondria

7. Pentose Phosphate Pathway:

• Produces NADPH and ribose-5-phosphate (for nucleotide synthesis) from glucose-6-phosphate.
• Location: Cytoplasm

8. Respiration:

• Oxidation of organic molecules (glucose, fatty acids) to generate ATP.
• Includes glycolysis, TCA cycle, and electron transport chain.
• Location: Cytoplasm and mitochondria.

Conclusion: 
Carbohydrate metabolism in plants encompasses a range of processes including photosynthesis for sugar synthesis, glycolysis for glucose breakdown, and various pathways for storage and utilization of carbohydrates. These pathways collectively ensure a continuous supply of energy and structural components essential for plant growth and development.

Q8:
(a) How has food production, including horticultural crops, changed in India during the last one decade ? Write down its impact on food and nutritional security.    (20 Marks)
Ans: 
Introduction: 
Over the last decade, India has witnessed significant changes in food production, particularly in horticultural crops. These changes have had a profound impact on food and nutritional security in the country.

Changes in Food Production:

• Diversification of Crops: There has been a notable shift towards the cultivation of horticultural crops like fruits, vegetables, and spices. For example, the area under fruits and vegetables has increased.

• Technological Advancements: Adoption of modern agricultural practices, improved irrigation facilities, and increased use of technology have contributed to higher yields in horticulture.

• Organic Farming and Sustainable Practices: There is a growing emphasis on organic farming and sustainable agriculture, leading to healthier and more environmentally-friendly food production.

• Crop Variety and Hybridization: The introduction of high-yielding varieties and hybrid seeds has led to increased productivity in horticultural crops.

Impact on Food and Nutritional Security:

• Dietary Diversity: Increased production of horticultural crops has diversified the diet of people, providing a wider range of essential nutrients.

• Improved Nutrition: Availability of fruits and vegetables has improved the overall nutritional status of the population, addressing deficiencies in vitamins and minerals.

• Income Generation: Horticulture has become a lucrative source of income for farmers, contributing to poverty reduction and economic growth.

• Reduced Post-Harvest Losses: Horticultural crops often have shorter shelf lives, reducing post-harvest losses and ensuring a higher proportion of the produce reaches consumers.

Conclusion: 
The transformation in food production, especially the emphasis on horticultural crops, has positively impacted food and nutritional security in India. Diversification, technological advancements, and sustainable practices have not only improved dietary diversity and nutrition but also enhanced the economic well-being of farmers.

(b) Write down the various programmes run by State and Central Governments for ensuring food security in our country. Briefly discuss the strategies for sustainable agricultural production.    (20 Marks)
Ans: 
Introduction: 
Ensuring food security is a critical goal for governments, both at the state and central levels. Various programs have been implemented to achieve this, alongside strategies for sustainable agricultural production.

Programmes for Food Security:

• Public Distribution System (PDS): It provides subsidized food grains to eligible beneficiaries through a network of fair price shops.

• Mid-Day Meal Scheme: This program aims to improve the nutritional status of school-going children by providing cooked meals in schools.

• Integrated Child Development Services (ICDS): ICDS provides supplementary nutrition, immunization, and health check-ups to pregnant women, lactating mothers, and children below 6 years.

• National Food Security Act (NFSA): NFSA aims to provide food and nutritional security by ensuring access to adequate quantities of quality food at affordable prices.

Strategies for Sustainable Agricultural Production:

• Crop Diversification: Encouraging farmers to cultivate a variety of crops helps in reducing the risk of crop failure and promotes sustainable land use.

• Promotion of Organic Farming: Organic farming practices minimize the use of synthetic inputs, promote soil health, and reduce environmental impacts.

• Water Conservation and Management: Efficient water use, through techniques like drip irrigation and rainwater harvesting, is crucial for sustainable agriculture.

• Integrated Pest Management (IPM): IPM focuses on natural pest control methods, reducing reliance on chemical pesticides.

Conclusion: 
Government programs like PDS, Mid-Day Meal, ICDS, and NFSA play a vital role in ensuring food security. In tandem, promoting sustainable agricultural practices such as crop diversification, organic farming, water conservation, and IPM are essential for long-term food security and environmental sustainability.

(c) Classify foods on the basis of their functions. Write down a balanced diet for a sedentary man and woman in India.    (10 Marks)
Ans:
Introduction: 
A balanced diet provides all the essential nutrients necessary for optimal health and well-being. It should be tailored to meet the specific needs of individuals based on factors like age, gender, and activity level.

Classification of Foods by Function:

• Energy-Giving Foods:
  Examples: Carbohydrates like rice, wheat, and potatoes provide the primary source of energy.

• Body-Building Foods:
  Examples: Proteins from sources like lean meat, fish, legumes, and dairy products aid in tissue repair and muscle growth.

• Protective Foods:
  Examples: Fruits and vegetables are rich in vitamins, minerals, and antioxidants that protect against diseases and support overall health.

• Regulating Foods:
  Examples: Foods high in fiber like whole grains, fruits, and vegetables help regulate digestion and prevent constipation.

Balanced Diet for a Sedentary Man and Woman in India:
1. For a Sedentary Man:

• Energy-Giving Foods: 55-60% of the diet (e.g., whole grains, cereals)
• Body-Building Foods: 10-15% of the diet (e.g., lean protein sources like poultry, legumes)
• Protective Foods: 25-30% of the diet (e.g., a variety of fruits and vegetables)
• Regulating Foods: Adequate fiber intake (e.g., whole grains, fruits, vegetables)

2. For a Sedentary Woman:

• Energy-Giving Foods: 55-60% of the diet (e.g., whole grains, cereals)
• Body-Building Foods: 10-15% of the diet (e.g., lean protein sources like legumes, dairy products)
• Protective Foods: 25-30% of the diet (e.g., a variety of fruits and vegetables)
• Regulating Foods: Adequate fiber intake (e.g., whole grains, fruits, vegetables)

Conclusion: 
A balanced diet tailored to individual needs is crucial for maintaining health and preventing nutritional deficiencies. By classifying foods based on their functions, one can ensure a well-rounded and nutritious diet that supports overall well-being.