UPSC Mains Answer PYQ 2024: Agriculture Paper 1 (Section- A) | Agriculture Optional for UPSC PDF Download

Q1: Answer the following questions in about 150 words each: (10 × 5 = 50 marks)
(a) Briefly discuss the principles of agro-ecology.
Ans: Agro-ecology is an integrated approach that applies ecological concepts and principles to optimize the interactions between plants, animals, humans, and the environment within agricultural systems. It is not just a set of agricultural practices but also a science, movement, and set of principles for sustainable farming.

Principles of Agro-ecology:
Enhancement of Biodiversity:

• Promotes diverse cropping systems (e.g., intercropping, agroforestry).
• Encourages use of indigenous crop varieties and mixed farming.

Synergy Creation:

• Ensures productive interactions among system components (e.g., crops-livestock integration).
• Helps reduce the dependence on external inputs.

Recycling of Resources:

• Nutrients, biomass, and energy are reused within the farm ecosystem.
• For example, composting organic residues and using green manure.

Efficiency in Resource Use:

• Efficient utilization of solar energy, soil nutrients, and water.
• Encourages low-input agriculture with minimal environmental impact.

Resilience to Stresses:

• Builds resistance against pests, diseases, and climate change through diversified systems.
  Example: Millets withstand drought better than paddy.

Human and Social Values:

• Focuses on food sovereignty, local knowledge, and equitable food systems.

Agro-ecology offers a sustainable alternative to industrial agriculture by harmonizing productivity with environmental conservation and social equity. Its principles guide farmers toward resilient, inclusive, and sustainable food systems.

(b) What are the factors responsible for low production and productivity of pulses in India? Discuss strategies adopted for enhancing the pulse production and productivity.
Ans:Pulses are vital in Indian agriculture for their high protein content and nitrogen-fixing ability, yet their productivity remains low compared to cereals.

Factors Responsible:

• Rainfed Cultivation: Over 85% of pulse area is under rainfed conditions, making crops vulnerable to moisture stress.
• Marginal Lands: Grown on less fertile lands with poor soil management and inadequate irrigation.
• Lack of HYVs (High-Yielding Varieties): Limited development and adoption of improved, pest-resistant pulse varieties.
• Pest and Disease Pressure: Pod borers, wilt, and yellow mosaic virus significantly reduce yield.
• Low Input Use: Minimal use of fertilizers, irrigation, and plant protection measures.

Strategies for Improvement:
National Food Security Mission (NFSM): Launched to increase area, production, and productivity of pulses through better inputs and practices.

1. Development of HYVs and Hybrid Pulses: Varieties like Pusa 16 (arhar) and IPM 2-3 (mung) introduced.
2. Pulse Villages Initiative: Promotes concentrated efforts in clusters to showcase improved technologies.
3. Integrated Pest Management (IPM): Focus on eco-friendly pest control.
4. Market Support and MSP: Assured procurement and price incentives to encourage pulse cultivation.

A multipronged approach combining better agronomy, varietal improvement, support price, and technology adoption can bridge the yield gap and boost pulse production in India.

(c) Describe the objectives of social forestry. Write down the plant species suitable for social forestry.
Ans: Social forestry involves the management and protection of forests and afforestation on barren lands with the purpose of helping environmental, social, and rural development.

Objectives of Social Forestry:

1. Fuelwood and Fodder Supply: Reduce pressure on natural forests by meeting rural demand for fuelwood and fodder.
2. Environmental Protection: Afforestation of degraded lands helps prevent soil erosion and improve biodiversity.
3. Employment and Income Generation: Provides livelihoods to rural communities through nursery raising, planting, and harvesting.
4. Community Participation: Empowers local communities to manage natural resources sustainably.
5. Improved Microclimate: Helps in improving soil health and micro-climate for sustainable agriculture.

Suitable Plant Species:

• Fuelwood Trees: Acacia nilotica, Prosopis juliflora, Dalbergia sissoo
• Fodder Trees: Leucaena leucocephala, Albizia lebbeck
• Fruit Trees: Mangifera indica (Mango), Psidium guajava (Guava)
• Multipurpose Trees: Azadirachta indica (Neem), Eucalyptus spp., Bamboo

Social forestry is a people-centric solution that balances ecological sustainability with social needs. It is crucial for improving green cover, rural livelihoods, and community empowerment.

(d) Discuss the cultural methods of weed control.
Ans: Weeds compete with crops for nutrients, light, water, and space, leading to reduced yield. Cultural methods of weed control are preventive strategies embedded within standard farming practices to suppress weeds naturally.

Cultural Methods of Weed Control:

• Crop Rotation: Alternating crops with different weed-suppressing abilities reduces weed populations.
  Example: Alternating rice with legumes.
• Tillage: Deep ploughing and timely harrowing expose weed seeds to desiccation and predation.
• Stale Seedbed Technique: Allowing weeds to germinate before planting and then removing them reduces weed pressure.
• Timely Sowing and Narrow Spacing: Sowing crops at the right time and maintaining optimal spacing allows faster canopy closure to suppress weeds.
• Use of Competitive Crops: Fast-growing and tall crops like maize or sorghum can outcompete weeds.
• Mulching: Applying crop residues or plastic mulch limits sunlight, thus suppressing weed germination.

Cultural weed control is an eco-friendly and cost-effective approach that enhances crop yield while reducing herbicide dependency. Integration with other methods leads to sustainable weed management.

(e) What are the two steps of nitrification and enlist micro-organisms responsible for each? Write down the importance of nitrification.
Ans: Nitrification is a crucial step in the nitrogen cycle that converts ammonia into nitrate, making nitrogen available to plants in a usable form.

Steps of Nitrification and Micro-organisms:

1. Ammonia to Nitrite (NH₃ → NO₂⁻): Carried out by bacteria like Nitrosomonas and Nitrosococcus.
2. Nitrite to Nitrate (NO₂⁻ → NO₃⁻): Carried out by bacteria like Nitrobacter and Nitrococcus.

Importance of Nitrification:

1. Plant Nutrition: Nitrate (NO₃⁻) is the most accessible form of nitrogen absorbed by plants for protein synthesis.
2. Soil Fertility: Enhances nitrogen availability, crucial for healthy plant growth.
3. Soil Ecosystem Balance: Prevents accumulation of toxic ammonia and maintains microbial equilibrium.
4. Environmental Significance: Essential in wastewater treatment and mitigating ammonia toxicity in ecosystems.

Examples:

• In rice fields, applying ammonium fertilizers leads to nitrification, providing nitrate to the crop.
• In aquaponics, nitrifying bacteria maintain water quality by converting fish waste ammonia into nitrates for plant use.

Nitrification is a vital biological process driven by specialized bacteria. It sustains plant productivity and ecological balance, making it indispensable for agriculture and environmental health.

Q2: 
(a) Write down the physical environmental factors affecting the crop production. Discuss the effects of changing rainfall pattern on crop production in India. (20 marks)
Ans: Agriculture is a climate-sensitive activity. The physical environment provides the natural framework in which crops grow, develop, and yield. In India, where a significant portion of agriculture is rainfed, physical environmental factors play a central role in determining crop performance. These factors not only affect crop growth but also influence soil health, pest dynamics, and cropping cycles. Among them, changing rainfall patterns due to climate change have emerged as a major concern for sustainable agricultural productivity.

Physical Environmental Factors Affecting Crop Production
Rainfall and Water Availability:

• Determines soil moisture availability, groundwater recharge, and irrigation potential.
• Both excess and deficit rainfall adversely affect crop growth and quality.
• Example: Droughts in Marathwada and floods in Assam reduce productivity drastically.

Temperature:

• Influences enzymatic activity, germination, flowering, and fruiting.
• High temperatures lead to heat stress, while frost affects rabi crops.
  Example: Wheat suffers during terminal heat; mustard yields drop due to early temperature rise.

Solar Radiation:

• Drives photosynthesis and influences crop maturity.
• Low light intensity reduces productivity.

Soil Type and Fertility:

• Determines nutrient availability, water retention, and root development.
• Poor or degraded soils affect productivity adversely.

Topography and Altitude:

• Affects drainage, erosion, and microclimate.
• Hilly areas have restricted mechanization and soil loss issues.

Atmospheric Humidity and Wind:

• Humidity affects transpiration and disease incidence.
• Strong winds can damage crops and increase evapotranspiration.

Effect of Changing Rainfall Patterns in India
Delayed Monsoons:

• Causes late sowing, affects crop calendars (especially kharif crops like rice, maize).

Irregular and Erratic Rainfall:

• Leads to water stress during critical crop stages.
• Increases the risk of crop failure in rainfed regions.

Increased Frequency of Floods/Droughts:

• Leads to loss of standing crops and soil degradation.

Changing Rainfall Intensity:

• Heavy downpours cause runoff and reduce groundwater recharge.
• Soil erosion and leaching of nutrients also occur.

Example: In 2023, erratic rainfall in Maharashtra led to soybean crop failure, while excess rain in Punjab delayed rice harvesting and damaged yield.

Changing rainfall patterns, driven by climate change, pose a serious threat to India’s food security. Adaptive measures like drought-resistant varieties, efficient irrigation systems, and crop insurance must be promoted to enhance resilience.

(b) Describe the improved cultivation practices of Chickpea under the following heads: (20 marks)
(i) Improved varieties
(ii) Seed rate and row to row spacing
(iii) Nutrient management
(iv) Weed management
(v) Insect-pest and disease management
Ans: Chickpea, or gram, is one of the most important pulse crops grown in India during the rabi season. It is rich in protein, improves soil fertility through nitrogen fixation, and supports sustainable agriculture. Despite its significance, chickpea yields in India can be improved through scientific cultivation practices. Here is a detailed look into the improved cultivation practices of chickpea under various agronomic heads.

(i) Improved Varieties

• Selection of disease-resistant and climate-resilient varieties is key.
• Desi Types (small seed size): Pusa 256, JG 11, JG 130, JG 16 (resistant to wilt).
• Kabuli Types (large seed size): Pusa 1003, KAK 2, PKV Kabuli-2 (good market value).
• These varieties are early-maturing, pest-resistant, and suitable for different agro-climatic zones.

(ii) Seed Rate and Spacing
Seed Rate:

• Desi: 75–100 kg/ha
• Kabuli: 100–125 kg/ha (larger seed size)

Spacing:

• Row-to-row: 30–45 cm
• Plant-to-plant: 10–12 cm

Wider spacing improves air circulation and reduces disease incidence.

(iii) Nutrient Management

• Chickpea requires balanced fertilization despite being a legume.
• FYM: 5–10 tonnes/ha improves soil structure and microbial activity.
• Fertilizer Dose: 20 kg N, 60 kg P₂O₅, 40 kg K₂O per ha (basal).

Micronutrients:

• Zinc sulfate (25 kg/ha) in zinc-deficient soils
• Rhizobium + PSB seed treatment enhances biological nitrogen fixation

Biofertilizers: Seed inoculation with Rhizobium and PSB enhances nitrogen fixation and phosphorus solubilization.

(iv) Weed Management

• Critical Period: First 30–45 days after sowing
  Weeding Practices: Manual weeding at 25 and 45 DAS

• Herbicides: Pre-emergence: Pendimethalin @ 1.0 kg a.i./ha
  Post-emergence: Imazethapyr @ 75 g a.i./ha

(v) Insect-Pest and Disease Management
Insect Pests:
Pod borer (Helicoverpa armigera):

• Helicoverpa armigera (Pod borer): Controlled using neem-based pesticides, NPV, or chemical sprays like Spinosad or Emamectin.

Diseases:

• Fusarium Wilt: Controlled by resistant varieties and seed treatment with Trichoderma.
• Ascochyta Blight: Managed by crop rotation and fungicides (Mancozeb or Carbendazim).

Adoption of these improved practices ensures higher yield, better quality, and reduced crop loss. Government programs and farmer training should promote these techniques widely.

(c) Discuss about the cropping patterns of Middle Gangetic Plain and Western Plateau and hills. (10 marks)
Ans: Cropping patterns refer to the yearly sequence and spatial arrangement of crops grown on a particular piece of land. They vary across regions based on topography, soil, climate, water availability, and socio-economic factors. India’s vast diversity in agro-climatic zones results in multiple cropping systems. This section explores the typical cropping patterns of the Middle Gangetic Plain and the Western Plateau and Hills.

1. Middle Gangetic Plain (Eastern Uttar Pradesh, Bihar)
Key Features:

• Dominated by fertile alluvial soils and dense canal and groundwater irrigation.
• Receives 1000–1600 mm annual rainfall.
• Flood-prone lowlands and high population density.

Major Cropping Patterns:
Rice–Wheat Cropping System (Dominant)

• Rice in kharif and wheat in rabi.
• Intensive and input-responsive.

Rice–Lentil/Mustard/Maize

• Lentils and mustard as rabi crops.
• Maize gaining popularity due to shorter maturity period.

Sugarcane–Wheat–Green Gram (Moong)

• In high-water table regions, e.g., western Bihar and eastern UP.

Vegetable Cultivation:

• Brinjal, cauliflower, and potato intensively grown near towns.

New Trends:

• Shift toward short-duration paddy and diversification into horticulture.

2. Western Plateau and Hills (Madhya Pradesh, Chhattisgarh, Maharashtra)
Key Features:

• Characterized by undulating terrain, red and black soils, and limited irrigation.
• Rainfall ranges between 700–1200 mm; mostly rainfed agriculture.

Major Cropping Patterns:
Soybean–Wheat / Soybean–Chickpea

• Popular in Madhya Pradesh and Vidarbha.
• Makes best use of available soil moisture and soil type.

Cotton–Chickpea / Sorghum–Pigeonpea

• In regions with black soil and moderate rainfall.

Kharif-Focused Cropping:

• Millets, pulses, and oilseeds like niger, sesame.

Mixed and Intercropping Systems:

• Intercropping of pigeonpea with maize or sorghum.
• Helps mitigate climate risks.

The Middle Gangetic Plain supports intensive, high-input agriculture, while the Western Plateau and Hills rely more on rainfed and diversified cropping systems. Understanding regional cropping patterns helps in optimizing productivity, designing tailored policies, and ensuring resource-efficient, climate-resilient agriculture.

Q3:
(a) What is the Arnon and Stout (1939) criteria for plant nutrient essentiality? Give account of forms of each essential plant nutrient element absorbed by plants. (20 marks)
Ans: Plants require various elements for their normal growth, development, and reproduction. However, not all elements are essential. Arnon and Stout (1939) provided a scientific framework to identify whether a nutrient is essential for plant life, forming the cornerstone of modern plant nutrition science.

Arnon and Stout (1939) Criteria for Nutrient Essentiality
According to them, an element is considered essential if it meets three conditions:

• Absence Prevents Completion of Life Cycle: The plant cannot complete its vegetative or reproductive phases in the absence of the element.
• Irreplaceability: The deficiency of an essential element cannot be corrected or replaced by another element.
• Direct Involvement in Metabolism: The element must be directly involved in plant metabolism (e.g., enzyme activation, photosynthesis, or structural role in cell walls).

Forms of Essential Nutrient Elements Absorbed by Plants
Plants absorb nutrients in inorganic, ionic, or water-soluble forms from the soil solution. These essential nutrients are categorized into macronutrients and micronutrients based on the quantity required.

Macronutrients:

1. Nitrogen (N): Absorbed as NO₃⁻ (nitrate) and NH₄⁺ (ammonium)
2. Phosphorus (P): Absorbed as H₂PO₄⁻ and HPO₄²⁻
3. Potassium (K): Absorbed as K⁺
4. Calcium (Ca): Absorbed as Ca²⁺
5. Magnesium (Mg): Absorbed as Mg²⁺
6. Sulphur (S): Absorbed as SO₄²⁻

Micronutrients:

1. Iron (Fe): Fe²⁺ and Fe³⁺
2. Manganese (Mn): Mn²⁺
3. Zinc (Zn): Zn²⁺
4. Copper (Cu): Cu²⁺
5. Boron (B): H₃BO₃, BO₃³⁻
6. Molybdenum (Mo): MoO₄²⁻
7. Chlorine (Cl): Cl⁻
8. Nickel (Ni): Ni²⁺

The Arnon and Stout criteria are fundamental in understanding plant nutrition and nutrient management. Knowledge of the specific forms in which nutrients are absorbed helps in formulating fertilizers, diagnosing deficiencies, and guiding sustainable nutrient use in agriculture.

(b) What do you mean by Forest products? Write about the value added products from forest. (20 marks)
Ans: Forests are not just reservoirs of biodiversity and ecological balance—they also provide valuable products that support rural livelihoods, industry, and national economies. These are broadly categorized into Timber and Non-Timber Forest Products (NTFPs), with the potential for value addition through processing and innovation.

What are Forest Products?
Forest products are materials derived from forest ecosystems, either through direct harvesting or secondary processing. They are grouped into:

1. Timber Products: Include wood used for furniture, construction, plywood, fuelwood, and paper.
   E.g., Teak, Sal, Deodar.
2. Non-Timber Forest Products (NTFPs): Include all other biological materials apart from timber.
   E.g., Bamboo, lac, resins, gums, honey, medicinal plants, wild fruits, fodder.

Value-Added Products from Forests
Value addition involves processing forest raw materials to improve their economic worth, shelf-life, and market appeal.

1. Bamboo-Based Products:

• Furniture, toothpicks, agarbatti sticks, baskets, flooring tiles.
  Modern uses: bamboo textiles, biodegradable packaging.

2. Herbal and Medicinal Products:

• Essential oils from lemongrass, eucalyptus.
• Ayurvedic formulations from neem, ashwagandha, turmeric.

3. Resins and Gums:

• Rosin and turpentine extracted from pine trees used in paints and varnishes.
• Gum arabic from Acacia used in the food and pharmaceutical industries.

4. Lac and Natural Dyes:

• Lac processed into bangles, sealing wax, and polishes.
• Natural dyes from turmeric, madder used in textiles.

5. Wild Edibles:

• Tamarind pulp, amla candy, mahua sweets and oil, jackfruit flour.

6. Beekeeping Products:

• Honey, beeswax, propolis are marketed through cooperatives and self-help groups.

Forests offer immense economic potential beyond timber. Promoting value-added products from forests supports rural entrepreneurship, women’s livelihoods, and sustainable forest management. Government initiatives like TRIFED and Van Dhan Vikas Kendra are essential in scaling these efforts.

(c) Give account of soil fertility evaluation techniques. Enlist the points to be considered along with soil test values for fertiliser dose recommendation. (10 marks)
Ans: Soil fertility evaluation is essential to determine the nutrient status of soil and guide the proper use of fertilizers. It helps ensure balanced fertilization, improved crop yield, and environmental safety. Various techniques have been developed to assess soil fertility effectively.

Soil Fertility Evaluation Techniques
Soil Testing:

• Most commonly used method.
• Soil samples analyzed for macronutrients (N, P, K) and micronutrients (Zn, Fe, B, etc.).
• Helps in identifying nutrient deficiencies and toxicities.

Plant Tissue Analysis:

• Measures nutrient concentrations in plant leaves or tissues.
• Indicates the nutrient uptake efficiency and hidden deficiencies.

Biological Methods:

• Use of bioassays with indicator plants to assess nutrient availability.
  Example: Sunflower or maize used to test phosphorus status.

Field Trials:

• On-farm fertilizer trials under actual growing conditions.
• Measures crop response to different fertilizer treatments.

Geospatial and Remote Sensing Tools:

• Use of GIS and drones for mapping fertility across fields.
• Facilitates site-specific nutrient management.
  

Points to Consider for Fertilizer Dose Recommendations
Soil Test Values:

• Nutrient availability classified as low, medium, or high.
• Fertilizer doses adjusted based on soil status.

Crop Nutrient Requirement:

• Different crops have varying nutrient needs.
  Example: Rice requires more nitrogen than pulses.

Crop Variety and Yield Target:

• High-yielding varieties require higher inputs.

Soil Type and Texture:

• Sandy soils need frequent, split applications due to leaching losses.

Cropping History and Rotation:

• Previous crops influence nutrient demand.
• Legumes contribute nitrogen to succeeding crops.

Irrigation and Rainfall:

• Nutrient mobility is affected by moisture availability.

Organic Matter Content:

• Soils rich in organic matter release nutrients slowly and steadily.

Use of Biofertilizers:

• Complement chemical fertilizers, especially for nitrogen and phosphorus.

Soil fertility evaluation enables precision farming and rational use of fertilizers. Integrating scientific techniques with farmers’ traditional knowledge ensures soil health and sustainable productivity. Regular soil testing and nutrient budgeting should be promoted through extension services and government support.

Q4:
(a) Explain the term conventional and conservation tillage. Give account of their comparative effects on soil properties and green house gas emissions. (20 marks)
Ans: Tillage is a mechanical operation used in agriculture to prepare the soil for planting by modifying its structure. It influences soil health, crop productivity, and environmental outcomes. Two major tillage systems are Conventional Tillage and Conservation Tillage. These systems differ significantly in their impact on soil properties and greenhouse gas (GHG) emissions.

Conventional Tillage

• Involves intensive plowing and soil disturbance.
• Practices include moldboard plowing, harrowing, and multiple passes over the field.
• Soil is often left bare between crops, increasing exposure to wind and water erosion.

Conservation Tillage

• Minimizes soil disturbance by retaining at least 30% of crop residue on the soil surface.
• Includes practices like no-till, strip-till, mulch-till, and ridge-till.
• Promotes sustainable farming by improving soil health and reducing erosion.

Comparative Effects on Soil Properties

Comparative Effects on Greenhouse Gas Emissions
Carbon Dioxide (CO₂):

• Conventional tillage releases more CO₂ due to breakdown of organic matter.
• Conservation tillage increases carbon sequestration and lowers CO₂ emissions.

Nitrous Oxide (N₂O): May increase in conservation tillage due to anaerobic conditions under residues.

Methane (CH₄): Minimal impact in upland systems but no-till can reduce CH₄ emissions in rice fields.

Examples

• In India, Punjab and Haryana have shifted toward conservation tillage in wheat-paddy systems using Happy Seeder to retain crop residues.
• Brazil’s Cerrado region has seen soil carbon buildup through widespread adoption of no-till practices.

Conservation tillage emerges as an eco-friendly alternative to conventional tillage. While it has minor trade-offs like potential for increased N₂O emissions, its benefits in improving soil health and mitigating climate change are substantial. Adoption should be encouraged through awareness and policy support.

(b) Discuss the Remote sensing system used for ecosystem analysis. Briefly discuss the use of Remote sensing for drought monitoring. (20 marks)
Ans: Remote sensing refers to the science of acquiring information about Earth’s surface using satellites or aerial platforms. It has revolutionized ecosystem analysis by providing spatial and temporal data that are crucial for understanding environmental patterns and changes.

Remote Sensing for Ecosystem Analysis
Satellite Sensors

• Use of sensors like Landsat, MODIS, and Sentinel.
• Capture data in visible, infrared, and microwave bands.
• Help in monitoring land use/land cover, deforestation, and vegetation health.

Vegetation Indices

• NDVI (Normalized Difference Vegetation Index) helps assess vegetation vigor.
• EVI (Enhanced Vegetation Index) corrects for atmospheric influences and canopy background.

Forest and Biodiversity Mapping

• Monitoring forest degradation, species habitat, and biomass estimation.
  Example: Mapping tiger reserves using LiDAR and hyperspectral imaging.

Wetland and Coastal Ecosystems

• Satellite-based analysis helps monitor mangrove health, coral bleaching, and eutrophication.

Carbon Cycle and Ecosystem Productivity

• Remote sensing estimates Net Primary Productivity (NPP) and carbon fluxes, aiding climate models.

Remote Sensing for Drought Monitoring
Drought Indicators

• Vegetation Condition Index (VCI) and Temperature Condition Index (TCI).
• Soil Moisture Index (SMI) using microwave remote sensing (e.g., SMAP satellite).

Advantages

• Real-time, large-area monitoring.
• Early warning systems for drought preparedness.

Application in India

• The Mahalanobis National Crop Forecast Centre (MNCFC) uses remote sensing for drought monitoring.
• Bhuvan portal (ISRO) provides drought maps and indices.

Remote sensing is an invaluable tool in ecosystem analysis and drought monitoring. Its real-time data, wide coverage, and cost-efficiency make it essential for environmental planning, disaster mitigation, and climate resilience.

(c) Describe in detail about the weed control measures in Black Gram and Sesame. (10 marks)
Ans: Weed control is an essential part of crop production management. Weeds are unwanted plants that compete with crops for nutrients, water, sunlight, and space, leading to reduced yields. In crops like Black Gram (Vigna mungo) and Sesame (Sesamum indicum), which are usually grown during the Kharif season, the problem of weeds is particularly severe during the initial growth stages. If not managed on time, weeds can reduce yield by 30–50% or even more.

Effective weed management requires an integrated approach combining cultural, mechanical, and chemical control methods.

Weed Control Measures in Black Gram
Cultural Methods

• Timely Sowing: Sowing at the onset of monsoon gives the crop a head start over weeds.
• Crop Rotation: Alternating Black Gram with cereals like maize or sorghum disrupts weed cycles.
• Intercropping: Growing Black Gram with maize or pearl millet reduces weed population due to shading.
• Mulching: Use of straw or plastic mulch suppresses weed growth by blocking sunlight.

Mechanical Methods

• Manual Weeding: Hand weeding at 20 and 40 days after sowing (DAS) is highly effective and commonly practiced in smallholder fields.
• Use of Weeders: Tools like wheel hoes or tine weeders help reduce labor costs and weed pressure in wider-spaced crops.

Chemical Methods

• Pre-emergence Herbicides: Application of Pendimethalin (1.0 kg a.i./ha) within 2 days of sowing controls germinating weed seeds.
• Post-emergence Herbicides: Imazethapyr (0.075 kg a.i./ha) at 20–25 DAS effectively controls broadleaf and grassy weeds.

These herbicides are safe for the crop and economical when labor is scarce.

Weed Control Measures in Sesame

Cultural Methods

• High Seed Rate: Increases canopy coverage, reducing weed emergence.
• Crop Rotation: Growing sesame after a leguminous crop or cereal reduces weed buildup.
• Timely Sowing: Ensures rapid early growth to outcompete weeds.
• Manual Weeding: Done at 15–20 DAS and again at 35–40 DAS, especially critical during the initial growth stage.

Mechanical Methods

• Line Sowing: Facilitates inter-row cultivation with tools.
• Wheel Hoe or Rotary Hoe: Used between rows to uproot weeds efficiently.

Chemical Methods

• Pre-plant Incorporation: Application of Fluchloralin (1.0–1.5 kg a.i./ha) before sowing and incorporated into the soil ensures early weed control.
• Pre-emergence Application: Alachlor (1.5 kg a.i./ha) provides control of annual grasses and some broadleaf weeds.

Examples

• In Andhra Pradesh, the use of Pendimethalin in Black Gram has shown 20–30% yield improvement compared to manual weeding alone.
• In Tamil Nadu, sesame farmers have adopted Fluchloralin application combined with inter-row cultivation for efficient weed suppression.

Effective weed control in Black Gram and Sesame is vital for ensuring good crop establishment and higher productivity. Since these crops are often grown by small and marginal farmers, an integrated weed management approach—combining timely cultural practices, mechanical tools, and judicious use of herbicides—can result in sustainable yield improvement and reduced production costs. Policymakers and extension services must promote awareness and training for integrated weed management to enhance productivity in pulse and oilseed farming.