UPSC Agriculture 2026 — Paper I

(a) Two linked demands in about 150 words: (i) list and classify the major sources of water pollution in India (point and non-point, including agricultural sources), and (ii) state the technological, agronomic and regulatory ways to check it. An answer that covers sources but omits remedies (or vice versa) is half an answer. (b) Two demands in about 150 words: (i) state the basic concepts of a farming system (system boundary, components, interaction, recycling, holism, sustainability, risk spreading), and (ii) briefly explain exactly three major indigenous (traditional, locally evolved) farming systems of India. Explaining fewer than three, or substituting modern IFS models for indigenous systems, loses the second half. (c) Two demands in about 150 words: (i) write the names of tree species suitable for agroforestry, with botanical names, and (ii) give the characteristics that make a tree suitable, i.e. the ideotype traits. A list of names with no traits, or traits with no named species, is half an answer. (d) Describe in about 150 words how weeds are disseminated (dispersed and spread), classified by agency - wind, water, animals, man and self-dispersal - with a named weed example for each agency, and mention the seed adaptations and crop mimicry that make dispersal effective. The phrase 'with appropriate examples' means named species are compulsory. (e) Write, in about 150 words, the physiological functions and the visual deficiency symptoms of the three secondary nutrients - calcium, magnesium and sulphur. Both halves are required for each of the three elements; an answer that treats only micronutrients or only NPK is off the question.

• Point sources: domestic sewage and industrial effluents
• Non-point sources: agricultural runoff (fertilisers, pesticides), urban runoff, mining, oil, thermal
• Control: STPs, ETPs, zero liquid discharge, Water Act 1974 with CPCB and SPCBs
• Preventive measures: INM and IPM, buffer strips, river programmes, awareness
• Definition: integration of crops, livestock, fish, trees with the household
• Concepts: sub-systems, inputs-outputs, recycling, synergy, diversity, sustainability
• Three indigenous systems named (jhum, home gardens, Apatani rice-fish or similar)
• Brief description of each
• Characteristics: fast growth, multipurpose, nitrogen fixing, deep roots, light crown, coppicing
• Suitable species named correctly (subabul, Gliricidia, khejri, poplar, shisham, neem)
• Use of each species (fodder, fuel, timber, green manure, shade)
• No allelopathy or competition with crops
• Wind, water, animals and birds, man and machinery, vegetative propagules
• Correct example for each agency
• Explosive dehiscence or crop-seed contamination
• Prevention linked to spread
• Secondary nutrients identified: calcium, magnesium, sulphur
• Functions: Ca (cell wall), Mg (chlorophyll), S (amino acids, proteins)
• Deficiency symptoms with mobility: Ca and S in young leaves, Mg in older leaves
• Distinct symptoms named (blossom-end rot, interveinal chlorosis, yellowing of young leaves)

(a) Two equal demands in about 300 words: (i) give an account of greenhouse gas emissions FROM agriculture - which gases, from which agricultural sources, in what proportions, with their global warming potentials, and (ii) state the mitigation strategies, organised by source (rice, livestock, soil nitrogen, residue, energy, soil carbon) rather than as a random list. (b) Three demands in about 300 words: (i) a lucid account of the SCOPE of precision farming in India - what it is, its enabling technologies, and where in Indian agriculture it can realistically be applied; (ii) enumerate its benefits; and (iii) enumerate its limitations specifically in the Indian scenario, i.e. tied to small holdings, cost and digital capacity, not generic ones. (c) Explain in about 150 words HOW Geographic Information Systems are used for two specific purposes: (i) land use analysis and (ii) micro-watershed planning. The answer must name the thematic layers, the GIS operations (overlay, DEM-based delineation, weighted multi-criteria analysis, change detection) and the outputs, not merely define GIS.

• Sources: methane from enteric fermentation, rice fields and manure; N2O from fertiliser and manure; CO2 from residue burning, soil and energy
• Relative global-warming potentials or India's share of emissions
• Mitigation in rice: AWD, SRI, direct-seeded and aerobic rice
• Mitigation in livestock and nutrients: feed, additives, 4R nutrient management, neem-coated urea; residue and soil management, agroforestry, renewables
• Definition and technology components: GPS, GIS, remote sensing, sensors, VRT, IoT, AI
• Scope: soil and nutrient, water, crop monitoring, drones, crops and systems suited, digital agriculture support
• Benefits: input efficiency, yield, environment, risk, traceability
• Limitations: small holdings, cost, skills, connectivity, data, service support, tenancy; ways forward
• Land use and land cover classification from satellite imagery and change detection
• Overlay analysis of soil, slope, climate and land capability for suitability
• Watershed delineation, morphometry and prioritisation using DEM, USLE, curve number
• Site selection of structures and monitoring impact; participatory use

(a) Discuss, in about 300 words, the vegetative (asexual, clonal) propagation methods used in FOREST tree species, each illustrated with a named tree example, and set out the limitations of vegetative propagation. Three things are compulsory: the methods, the suitable examples, and the limitations. (b) Discuss in detail, in about 300 words, the management practices of a RATOON crop of sugarcane - that is, the sequence of operations from harvesting the plant crop through stubble shaving, trash and gap management, nutrient, water, weed and plant protection management, with reasons for the practices and a statement of why ratoon yields decline. (c) Suggest, in about 150 words, suitable CHEMICAL weed management practices for four named crops - maize, moong (green gram), cotton and sugarcane. For each crop the answer must name herbicides with the mode of application (pre-plant incorporation, pre-emergence, post-emergence), the dose in terms of active ingredient per hectare and the time of application. All four crops must be covered.

• Meaning and reasons for vegetative propagation (clones, plus trees, seed orchards)
• Methods with forest examples: cuttings, root suckers, stumps, layering, grafting and budding, offsets, coppice, tissue culture
• Correct species examples (poplar, eucalypt, teak, sissoo, bamboo)
• Limitations: narrow genetic base, poor rooting of mature material, weak roots, cost, disease risk
• Meaning of ratoon and its advantages
• Harvest close to the ground, stubble shaving with fungicide, off-barring, gap filling
• Trash mulching, extra nitrogen (about 25% more), iron and zinc, irrigation
• Weed, pest and disease control, earthing up, number of ratoons
• Maize: atrazine pre-emergence with timing and dose, and post-emergence option
• Moong: pendimethalin pre-emergence, imazethapyr or quizalofop post-emergence
• Cotton: pendimethalin pre-emergence and post-emergence options with directed spray
• Sugarcane: atrazine or metribuzin pre-emergence, 2,4-D or halosulfuron later

(a) Three demands in about 300 words: (i) define soil consistency; (ii) define soil plasticity, including the Atterberg limits; and (iii) discuss briefly the various FORMS (classes) of soil consistency as described at the dry, moist, wet and cemented moisture states, closing with the agronomic significance for tillage. (b) Two demands in about 300 words: (i) define nitrification, giving the two-step reaction, the organisms and the enzymes; and (ii) describe the soil and management factors that affect the rate of nitrification - substrate supply, aeration, moisture, temperature, pH, C:N ratio, salinity, inhibitors and fertiliser practice - with their optimum ranges. (c) Explain briefly, in about 150 words, WHY available phosphorus increases in most soils after flooding (submergence). The answer must give the chemical reasons - reduction of ferric phosphate, convergence of pH, release of occluded P, competition of organic anions for sorption sites, mineralisation of organic P and faster diffusion - and should note the exceptions.

• Consistency defined as expression of cohesion and adhesion at various moisture
• Plasticity defined; Atterberg limits (plastic limit, liquid limit, plasticity index) and factors
• Forms in wet, moist and dry states with grades (sticky and plastic; friable; hard)
• Cemented consistency and importance for tillage and engineering
• Definition: biological oxidation of ammonium to nitrate
• Two steps and organisms: Nitrosomonas (NH4 to NO2), Nitrobacter (NO2 to NO3) with equations
• Factors: ammonium supply, aeration, moisture, temperature, pH, C:N ratio, salts
• Inhibitors and management (neem-coated urea, DCD, nitrapyrin) and significance
• Reduction of ferric phosphate to more soluble ferrous phosphate
• Reductive dissolution of iron oxide coatings releasing occluded P
• pH shift towards neutrality increasing solubility of Fe, Al and Ca phosphates
• Anion displacement by organic anions, mineralisation of organic P, greater diffusion

(a) Write, in about 150 words, the approaches to soil conservation - that is, the agronomic or biological measures, the mechanical or engineering measures, and the land-use and institutional approaches - organised as a classification rather than as a random list, and with the land capability and watershed basis stated. (b) Discuss briefly, in about 150 words, the criteria used to decide WHEN to irrigate a crop - the soil-moisture based, climatological or evaporation based, plant-indicator based, critical-growth-stage based and fixed-schedule approaches - with the indicative threshold values for each. (c) Describe, in about 150 words, the components of a drip irrigation system, and DRAW a schematic diagram. The diagram is explicitly asked for, so an answer without it is incomplete. The description should follow the water's path from source through the head control unit (pump, filters, fertigation) to the main, sub-main, laterals and emitters, with the function of each component. (d) Explain in about 150 words HOW agricultural prices are regulated in India through the agricultural price policy - the institutions (CACP, CCEA), the instruments (MSP, FRP, procurement, buffer stocks, PDS, PSS, MIS, PM-AASHA, trade and stock controls) and the cost concepts on which the minimum support price is fixed - and close with the limitations of the mechanism. (e) Write, in about 150 words, the sequential steps involved in preparing a farm plan - from the farm survey and resource inventory, through analysis of the present situation, setting objectives, identifying alternatives, evaluating them by budgeting or programming techniques, to selecting, implementing, monitoring and revising the plan. The answer must be a step-wise procedure, not an essay on farm management.

• Agronomic and biological measures (contour farming, strip cropping, mulching, cover crops, conservation tillage, agroforestry)
• Vegetative measures and windbreaks
• Mechanical measures (bunds, terraces, trenches, waterways, check dams)
• Watershed approach and choice by slope and soil
• Soil moisture criterion (depletion of about 50% available moisture, tensiometer)
• Plant indicators (wilting, leaf water potential, canopy temperature)
• Climatological approach: IW/CPE ratio or ET-based scheduling
• Critical growth stages and soil water balance
• Head unit: pump, filters, fertiliser tank or venturi injector, valves and gauges
• Main line, sub-main and flush valve
• Laterals and emitters with typical sizes and discharge
• Correct schematic diagram in flow order with labels
• MSP, CACP and the FRP for sugarcane with the basis of pricing (A2+FL at 1.5 times)
• Procurement by FCI, state agencies and NAFED; PM-AASHA; Market Intervention Scheme
• Buffer stocks, PDS, trade and stock policy under the Essential Commodities Act
• Market regulation such as APMC and e-NAM
• Farm inventory and survey of resources
• Analysis of situation and setting of objectives
• Alternatives and budgeting to select the best plan
• Implementation, monitoring and revision

(a) Classify irrigation water for suitability on the basis of its BORON content, in about 150 words. The expected answer is the standard boron-hazard classification (after Scofield and Wilcox) with the concentration limits in mg per litre for each class separated for boron-sensitive, semi-tolerant and boron-tolerant crops, together with named crops in each tolerance group and the soil conditions that modify the hazard. (b) Two demands in about 300 words: (i) CATEGORISE industrial effluents - by industry of origin and by the nature of the pollutant (organic and biodegradable, inorganic and chemical, acidic and alkaline, saline and sodic, heavy-metal bearing, oily, thermal) - and (ii) discuss briefly their effects on the PHYSICAL, CHEMICAL and BIOLOGICAL properties of soil, noting that the effect is dose-dependent. (c) Two demands in about 300 words: (i) discuss the problems of dryland (rainfed) agriculture in India - climatic, edaphic, agronomic, socio-economic and institutional; and (ii) state the ways to increase production and productivity in dryland areas, covering moisture conservation and rainwater harvesting, agronomic and varietal measures, nutrient management, alternate land use and integrated farming, and the policy and institutional support.

• Boron toxicity and narrow range between deficiency and toxicity
• Five classes (excellent to unsuitable) with ppm limits for sensitive, semi-tolerant and tolerant crops (Wilcox)
• Examples of sensitive, semi-tolerant and tolerant crops
• Soil influence and remedy (fine texture, leaching)
• Categories: organic-rich, inorganic and chemical, heavy metal bearing, thermal and radioactive, with sources
• Physical effects: pore clogging, dispersion by sodium, crusting, poor infiltration
• Chemical effects: pH change, salinity and sodicity, heavy metal accumulation, nutrient imbalance
• Biological effects and effects on crops; need for treatment
• Problems: erratic rainfall and drought, poor soils, low water-holding capacity, erosion, low input use, small holdings
• In-situ moisture conservation and water harvesting with supplemental irrigation
• Crop planning: drought-tolerant crops and varieties, intercropping, contingency plans, timely sowing
• Nutrient management, watershed approach, alternative land use and institutional support

(a) Two linked demands in about 300 words: (i) list and explain the various factors that affect farm profit, and (ii) discuss the decisions that are critical to earning good farm profits. 'Discuss' requires that each critical decision be named, explained and anchored in the farm-management principle that guides it, not merely listed. (b) Two demands in about 300 words: (i) differentiate extension education from extension service, bringing out that one is a discipline or body of knowledge and the other the organised machinery that delivers it; and (ii) discuss, with reasons, why extension education qualifies as an applied science. (c) Write, in about 150 words, the practices that constitute Integrated Watershed Management as a means of improving livelihood security - that is, the soil and moisture conservation, vegetative, production-system and institutional practices together, with the livelihood link made explicit rather than a bare list of conservation structures.

• Farm profit defined as value of output minus cost
• Factors: yield, prices, costs, scale, cropping intensity, technology and management, capital and marketing, risk and policy
• Critical decisions: what, how, how much, when to produce; marketing; financing; risk management
• Economic principles such as marginal returns and comparative advantage
• Differences on nature, objective, approach, time frame, focus, with examples
• Extension education as informal out-of-school education changing knowledge, attitude and skills
• Applied science: content from research, field experience and behavioural sciences (definition)
• Features: interdisciplinary, methods, scientific approach, problem-orientation
• Ridge-to-valley treatment: soil and moisture conservation
• Water harvesting and groundwater recharge
• Vegetative measures, agroforestry, improved crop and land management
• Livelihood activities, community institutions and convergence (PMKSY, rural employment programme)

(a) Two demands in about 300 words: (i) differentiate monitoring from evaluation of extension programmes on clear bases, and (ii) discuss the various types of evaluation - by timing, by who evaluates, by design and by focus - explaining what each type does rather than merely naming them. (b) Two demands in about 300 words: (i) discuss the rationale for farmers' markets in India - why direct producer-to-consumer markets were needed given the defects of the regulated mandi channel; and (ii) enlist, with suitable named examples, their impact on the various stakeholders - farmers, consumers, intermediaries, the state and the wider economy. (c) Briefly state, in about 150 words, the measures used to control wind erosion of soil - agronomic and vegetative, mechanical barriers, tillage and soil-management, and land-use measures - preferably prefaced by the principle on which wind-erosion control rests.

• Monitoring: continuous, during implementation, inputs-activities-outputs, corrective; evaluation: periodic judgement of worth and impact
• Differences on timing, purpose, focus, who does it, nature
• Types by timing: ex-ante, formative or concurrent, summative or ex-post
• Types by content and evaluator: input, process, output, outcome, impact; internal, external, participatory; quantitative and qualitative
• Rationale: fewer intermediaries, higher farmer share, fair prices for consumers, lower losses, access for small farmers
• Examples: Rythu Bazaar, Uzhavar Sandhai, Apni Mandi
• Impact on farmers, consumers, middlemen, government and environment
• Limitations and links with FPOs and e-NAM
• Principles: reduce wind velocity, cover soil, make soil less erodible
• Vegetative cover, residue mulch, windbreaks and shelterbelts with species
• Strip cropping, rough cloddy tillage across wind, soil amendments
• Sand dune stabilisation and grazing control