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Haryana BSEH Secondary NSQF Agriculture study materials
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Haryana BSEH Secondary NSQF Agriculture practice questions

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Question 1Agriculture and the Environment

In NSQF agriculture practice, which soil type is best suited for paddy cultivation because it can hold water for long periods?

  1. Rocky gravel soil
  2. Red laterite soil
  3. Clayey soil Correct answer.
  4. Sandy soil

Explanation

Clayey soil has very fine particles with small pore spaces, so water percolates slowly and stands in the field for a long time, which paddy needs. Sandy and gravelly soils drain too fast, and red laterite is generally well drained and acidic.

Question 2Agriculture and the Environment

A farmer wants to improve the water-holding capacity and nutrient status of a light sandy field. Which practice is most appropriate?

  1. Removing all crop residues after harvest
  2. Adding well-decomposed farmyard manure and green manure Correct answer.
  3. Flooding the field continuously for a month
  4. Deep ploughing to bury the topsoil

Explanation

Organic matter such as farmyard manure and green manure improves soil aggregation and increases the water-holding and nutrient-retention capacity of sandy soils. Continuous flooding, burying topsoil, and residue removal all degrade soil structure or fertility.

Question 3Agriculture and the Environment

Which of the following is a leguminous crop that fixes atmospheric nitrogen through root nodules?

  1. Wheat
  2. Mustard
  3. Maize
  4. Gram Correct answer.

Explanation

Gram is a pulse crop of the legume family and forms root nodules with Rhizobium bacteria that fix atmospheric nitrogen. Wheat, mustard, and maize are non-legumes and do not fix nitrogen in this way.

Question 4Agriculture and the Environment

Which irrigation method is most efficient in saving water in a row crop like cotton on a field with limited water supply?

  1. Uncontrolled channel flow
  2. Flood irrigation of the whole field
  3. Basin flooding around each plant
  4. Drip irrigation along the rows Correct answer.

Explanation

Drip irrigation delivers water slowly and directly to the root zone, reducing evaporation, deep percolation, and runoff. Flooding and uncontrolled channel flow waste large amounts of water and can waterlog the field.

Question 5Agriculture and the Environment

What is the main purpose of crop rotation in an agriculture system?

  1. To maintain soil fertility and break pest and disease cycles Correct answer.
  2. To grow the same crop every season for higher yield
  3. To eliminate the need for any irrigation
  4. To keep the field permanently fallow

Explanation

Rotating different crops, especially including legumes, restores nutrients, improves soil structure, and interrupts the life cycles of pests and diseases specific to one crop. Monocropping depletes nutrients and encourages pest build-up.

Question 6Agriculture and the Environment

Which of the following is an example of a biological method of weed control?

  1. Releasing a natural insect enemy of a weed Correct answer.
  2. Hand weeding in the field
  3. Burning the field before sowing
  4. Spraying a selective herbicide

Explanation

Biological weed control uses living organisms such as insects or pathogens that feed on or attack a specific weed. Herbicides are chemical, hand weeding is mechanical, and burning is a physical method.

Question 7Agriculture and the Environment

A farmer notices that a field previously cropped with wheat shows poor growth of the next wheat crop even though the same fertilizer was applied. Which explanation is most consistent with the principle of crop rotation?

  1. The field has lost the specific nutrients and root-zone health that wheat repeatedly removes Correct answer.
  2. The fertilizer applied was completely washed away before sowing
  3. Wheat always fails when grown after any other crop
  4. The soil temperature was too high for germination

Explanation

Continuous wheat depletes the same nutrients, encourages wheat-specific pests and diseases, and degrades soil structure, so yields decline even with similar fertilizer. Rotation with a different crop, especially a legume, restores balance in the root zone.

Question 8Agriculture and the Environment

Farmyard manure is best described as which type of nutrient source?

  1. An organic manure supplying nutrients slowly and improving soil structure Correct answer.
  2. A pesticide used to control soil insects
  3. A concentrated chemical fertilizer
  4. A soil fumigant applied before sowing

Explanation

Farmyard manure is an organic material that releases nutrients gradually as it decomposes and also adds organic matter that improves soil structure and water retention. It is not a concentrated chemical fertilizer, pesticide, or fumigant.

Question 9Agriculture and the Environment

Which practice best reduces soil erosion on a slopy field in the Shivalik foothills?

  1. Leaving the soil bare after harvest
  2. Removing all vegetation from the field bunds
  3. Ploughing up and down the slope
  4. Contour ploughing with a cover crop Correct answer.

Explanation

Contour ploughing follows the land contour so that each furrow acts as a small barrier to runoff, and a cover crop protects the soil surface from raindrop impact. Ploughing up and down the slope speeds water flow and increases erosion.

Question 10Agriculture and the Environment

Integrated Pest Management (IPM) in agriculture is best described as which approach?

  1. Combining cultural, mechanical, biological, and need-based chemical methods Correct answer.
  2. Applying the highest possible dose of pesticide at every stage
  3. Abandoning all pest control measures
  4. Relying only on chemical pesticides for all pests

Explanation

IPM combines several methods, including resistant varieties, cultural practices, mechanical removal, biological control, and judicious use of pesticides only when the pest population crosses the economic threshold. This reduces cost and avoids excessive chemical use.

Question 11Agriculture and the Environment

Which of the following describes the role of Rhizobium bacteria in legume cultivation?

  1. They decompose soil organic matter into humus
  2. They increase soil pH by releasing lime
  3. They control insect pests on the leaves
  4. They convert atmospheric nitrogen into a form usable by the plant inside root nodules Correct answer.

Explanation

Rhizobium forms a symbiotic association with legume roots, entering through root hairs and forming nodules where atmospheric nitrogen is reduced to ammonia that the plant can use. The plant, in turn, supplies the bacteria with carbohydrates.

Question 12Agriculture and the Environment

A farmer wants to control weeds in a standing crop without disturbing the crop plants physically. Which method is most suitable for selective control?

  1. Hand pulling of all weeds
  2. Deep inter-cultivation near the crop rows
  3. Selective herbicide application Correct answer.
  4. Burning the field surface

Explanation

A selective herbicide kills the target weeds while leaving the crop relatively unharmed when applied at the correct dose and stage. Hand pulling is laborious, deep inter-cultivation can damage crop roots, and burning would destroy the crop.

Question 13Agriculture and the Environment

What is the main environmental concern associated with excessive use of chemical nitrogen fertilizers?

  1. Complete loss of soil colour
  2. Immediate death of all earthworms
  3. Permanent loss of soil temperature
  4. Groundwater and surface water pollution through nitrate leaching and runoff Correct answer.

Explanation

Excess nitrate not taken up by crops can leach into groundwater or wash into surface water, causing contamination and eutrophication. This is a well-recognised environmental hazard of over-fertilization.

Question 14Agriculture and the Environment

Which of the following cropping patterns is an example of mixed cropping?

  1. Growing wheat and gram together in the same field in the same season Correct answer.
  2. Growing wheat in one season and paddy in the next
  3. Leaving the field fallow for a year
  4. Growing wheat alone in the entire field

Explanation

Mixed cropping means growing two or more crops together in the same field during the same season. Growing a single crop, sequential cropping, and fallowing are different practices.

Question 15Agriculture and the Environment

A farmer applies a pesticide that kills both the pest and its natural predator. What is the likely long-term consequence?

  1. Pest populations will decline permanently
  2. The crop will become resistant to all diseases
  3. Soil fertility will increase automatically
  4. Pest resurgence may occur because natural control is lost Correct answer.

Explanation

Broad-spectrum pesticides can eliminate natural enemies along with the pest, so the pest can rebound faster than its predators and cause resurgence. This is why IPM recommends selective and need-based pesticide use.

Question 16Agriculture and the Environment

Which of the following best explains why green manuring is beneficial before a cereal crop?

  1. It kills all soil-borne pathogens permanently
  2. It reduces the need for sunlight for the crop
  3. It makes the soil water-repellent
  4. It adds organic matter and nitrogen to the soil when the green plants are ploughed in Correct answer.

Explanation

Green manuring involves growing a quick-growing leguminous plant and ploughing it into the soil while still green, adding organic matter and nitrogen as it decomposes. It improves soil fertility and structure rather than making soil water-repellent.

Question 17Agriculture and the Environment

In a crop field, the presence of earthworms is generally considered beneficial because they:

  1. Improve soil porosity and nutrient cycling through burrowing and organic matter breakdown Correct answer.
  2. Consume the crop roots for food
  3. Fix atmospheric nitrogen directly in root nodules
  4. Kill all harmful insects in the soil

Explanation

Earthworms burrow through the soil, creating channels that improve aeration and water infiltration, and they break down organic matter, releasing nutrients in forms available to plants. They do not fix nitrogen in nodules or act as insect killers.

Question 18Agriculture and the Environment

A farmer in a semi-arid region wants to conserve soil moisture between two irrigations. Which combination of practices is most effective?

  1. Flooding the field daily
  2. Removing all plant residues and keeping soil bare
  3. Frequent shallow ploughing and mulching the soil surface Correct answer.
  4. Compacting the soil heavily with machinery

Explanation

Mulching covers the soil surface and reduces evaporation, while shallow ploughing breaks capillary continuity near the surface and limits upward water loss. Together they conserve moisture between irrigations.

Question 19Agriculture and the Environment

Which statement correctly distinguishes between a fertilizer and a pesticide in agricultural use?

  1. Fertilizers kill weeds, while pesticides supply nutrients
  2. Both are applied only to the soil surface
  3. Fertilizers supply plant nutrients, while pesticides control pests and diseases Correct answer.
  4. Both are used only to kill insects

Explanation

Fertilizers are materials that supply essential plant nutrients such as nitrogen, phosphorus, and potassium, whereas pesticides are substances used to control pests, diseases, or weeds. The two have distinct purposes and application methods.

Question 20Agriculture and the Environment

A farmer observes that a field receiving heavy irrigation with poor drainage has become waterlogged and crops are turning yellow. Which corrective measure is most appropriate?

  1. Applying more nitrogen fertilizer immediately
  2. Increasing irrigation further
  3. Providing drainage and reducing irrigation frequency Correct answer.
  4. Compacting the soil to reduce water flow

Explanation

Waterlogged soils lack oxygen in the root zone, which impairs nutrient uptake and causes yellowing. Improving drainage and reducing irrigation frequency restores aeration and root function. Adding more water or fertilizer worsens the problem.

Question 21Soil and Soil Management

Which soil particle size fraction is the smallest among the following?

  1. Fine sand
  2. Coarse sand
  3. Clay Correct answer.
  4. Silt

Explanation

Soil particles are graded by diameter, and clay is the finest fraction, with particles below about 0.002 mm. Sand is the coarsest of the mineral fractions and silt lies between sand and clay. Because clay is the smallest, it carries the greatest surface area per unit weight.

Question 22Soil and Soil Management

A soil sample feels gritty when rubbed between the fingers and shows a high proportion of quartz grains. Which texture class does this best describe?

  1. Loamy soil
  2. Clayey soil
  3. Sandy soil Correct answer.
  4. Silty soil

Explanation

Grittiness on rubbing is the field test for sand, since sand grains are coarse and dominated by quartz. Clay feels sticky and smooth, and silt feels smooth and floury rather than gritty. A high sand content therefore points to a sandy texture.

Question 23Soil and Soil Management

Which of the following is a primary macronutrient supplied to crops mainly through soil?

  1. Molybdenum
  2. Nitrogen Correct answer.
  3. Zinc
  4. Boron

Explanation

Nitrogen is one of the primary macronutrients, along with phosphorus and potassium, required by crops in large amounts. Zinc, boron and molybdenum are micronutrients needed only in trace quantities. Hence nitrogen is the correct choice among the options given.

Question 24Soil and Soil Management

Which soil organism is most directly responsible for decomposing organic matter and converting it into humus?

  1. Algae
  2. Nematodes
  3. Bacteria and fungi Correct answer.
  4. Earthworms alone

Explanation

Bacteria and fungi are the principal decomposers that break down plant and animal residues into simpler compounds and humus. Earthworms mix and aerate soil and fragment residues but do not carry out the main chemical decomposition. Nematodes and algae play other roles and are not the chief decomposers.

Question 25Soil and Soil Management

What is the main purpose of ploughing a field before sowing?

  1. To increase the clay content of the soil
  2. To loosen and aerate the soil for root growth Correct answer.
  3. To raise the pH of the soil
  4. To sterilise the soil of all microorganisms

Explanation

Ploughing breaks up compacted soil, improves aeration and water infiltration, and creates a seedbed for germination. It does not change the clay fraction, sterilise the soil, or by itself raise pH. The primary aim is physical loosening and aeration.

Question 26Soil and Soil Management

Which practice best conserves soil moisture in a rainfed field during a dry spell?

  1. Removing all plant cover from the field
  2. Mulching the soil surface with crop residues Correct answer.
  3. Flooding the field once and then leaving it bare
  4. Deep ploughing to expose subsoil

Explanation

A mulch of crop residues shades the soil surface and reduces evaporation, thereby conserving moisture. Exposing subsoil and removing plant cover increase evaporation and erosion. Bare soil after flooding loses moisture quickly to the atmosphere.

Question 27Soil and Soil Management

Which soil type is generally best suited for most field crops because it balances sand, silt and clay?

  1. Coarse gravel
  2. Pure sand
  3. Heavy clay
  4. Loam Correct answer.

Explanation

Loam contains a balanced mixture of sand, silt and clay, giving good aeration, water retention and nutrient supply. Pure sand drains too fast and holds few nutrients, while heavy clay is poorly aerated and hard to work. Gravel has very little water-holding capacity.

Question 28Soil and Soil Management

In the soil profile, which horizon is the zone of maximum accumulation of organic matter and is usually darkest in colour?

  1. B horizon
  2. C horizon
  3. R horizon
  4. O horizon Correct answer.

Explanation

The O horizon is the surface organic layer, rich in partly decomposed litter, and is typically dark. The B horizon is a subsoil zone of accumulation of clay and minerals, not of fresh organic matter. The C horizon is weathered parent material and the R horizon is bedrock.

Question 29Soil and Soil Management

A farmer applies gypsum to a sodic soil. What is the main chemical effect of this treatment?

  1. Organic matter content is increased sharply
  2. Soil pH is lowered by adding sulphuric acid directly
  3. Calcium replaces sodium on the exchange complex Correct answer.
  4. Sodium replaces calcium on the exchange complex

Explanation

Gypsum supplies calcium, which displaces sodium ions held on the clay exchange sites, allowing the sodium to be leached away. This improves soil structure and permeability. Gypsum does not add organic matter and does not work by directly adding acid.

Question 30Soil and Soil Management

Which nutrient deficiency in soil is most commonly corrected by growing a legume in rotation?

  1. Nitrogen Correct answer.
  2. Potassium
  3. Calcium
  4. Phosphorus

Explanation

Legumes form a symbiosis with Rhizobium bacteria, which fix atmospheric nitrogen in root nodules and enrich the soil. This mainly reduces the need for nitrogen fertiliser. Phosphorus, potassium and calcium are not fixed from the atmosphere by legumes.

Question 31Soil and Soil Management

Which statement correctly describes the relationship between soil organic matter and soil water-holding capacity?

  1. Increasing organic matter always decreases water-holding capacity
  2. Organic matter has no effect on water retention
  3. Increasing organic matter generally increases water-holding capacity Correct answer.
  4. Organic matter increases water-holding capacity only in sandy soils

Explanation

Organic matter and humus increase porosity and surface area, which raises the soil's ability to retain moisture. The effect is seen across soil types, though it is especially useful in sandy soils. It never reduces water-holding capacity.

Question 32Soil and Soil Management

Water draining downward through a soil profile carries dissolved salts and clay particles into lower layers. What is this process called?

  1. Capillary rise
  2. Salinisation
  3. Erosion
  4. Leaching Correct answer.

Explanation

Leaching is the downward movement of dissolved salts and fine particles through the profile with percolating water. Capillary rise moves water upward, erosion removes surface material laterally, and salinisation is the accumulation of salts near the surface.

Question 33Soil and Soil Management

Why is green manuring with a legume crop beneficial to soil?

  1. It increases soil compaction for better root anchorage
  2. It converts clay particles into sand particles
  3. It removes nitrogen from the soil permanently
  4. It adds organic matter and nitrogen when ploughed into the soil Correct answer.

Explanation

Green manuring involves growing a legume and ploughing it into the soil while green, adding organic matter and biologically fixed nitrogen. This improves structure and fertility. It does not remove nitrogen, compact soil, or change clay into sand.

Question 34Soil and Soil Management

Which conservation measure is most effective for reducing soil erosion on a sloping field?

  1. Removing all vegetation from the slope
  2. Contour bunding along the slope Correct answer.
  3. Ploughing straight up and down the slope
  4. Burning crop residues before sowing

Explanation

Contour bunds follow the slope's contour and slow down runoff, allowing water to infiltrate and reducing soil loss. Ploughing up and down the slope creates channels for fast runoff, while burning residues and removing vegetation leave the soil bare and vulnerable.

Question 35Soil and Soil Management

A soil test report shows a pH of 5.2. Which amendment is most appropriate to raise the pH for a crop sensitive to acidity?

  1. Ammonium sulphate
  2. Farmyard manure applied alone
  3. Agricultural lime Correct answer.
  4. Gypsum

Explanation

Agricultural lime, mainly calcium carbonate, neutralises soil acidity and raises pH. Gypsum supplies calcium and sulphur but has little effect on pH. Ammonium sulphate is an acidifying fertiliser and would lower pH further.

Question 36Soil and Soil Management

Which of the following best explains why heavy clay soils remain waterlogged after rain?

  1. They have many small pores and low permeability Correct answer.
  2. They have large pores and very high permeability
  3. They are always rich in organic matter
  4. They contain almost no clay particles

Explanation

Clay soils are dominated by fine pores with low hydraulic conductivity, so water drains slowly and the profile stays saturated. Large pores and high permeability would promote drainage, not waterlogging. Organic matter content does not explain the effect.

Question 37Soil and Soil Management

What is the principal reason for adding farmyard manure to soil before raising a crop?

  1. It kills soil-borne pathogens immediately
  2. It reduces the sand content of the soil
  3. It supplies organic matter and several nutrients Correct answer.
  4. It permanently raises the soil temperature

Explanation

Farmyard manure is a bulky organic source that improves structure, water retention and nutrient supply, especially nitrogen and micronutrients. It is not a sterilising agent and does not alter the mineral particle composition. Its effect on temperature is minor and temporary.

Question 38Soil and Soil Management

Which process converts ammonium nitrogen in the soil to nitrate nitrogen under aerobic conditions?

  1. Ammonification
  2. Nitrogen fixation
  3. Nitrification Correct answer.
  4. Denitrification

Explanation

Nitrification is the microbial oxidation of ammonium to nitrite and then nitrate in well-aerated soil. Denitrification reduces nitrate to nitrogen gas under anaerobic conditions, ammonification releases ammonium from organic matter, and fixation converts atmospheric nitrogen into combined forms.

Question 39Soil and Soil Management

A field shows patches of white salt crust on the surface and poor germination. Which soil condition is most likely?

  1. Strongly acidic soil with low pH
  2. Soil with very high organic matter
  3. Saline soil with high soluble salt concentration Correct answer.
  4. Soil with excessive earthworm activity

Explanation

A white surface crust and poor germination are typical signs of salinity, where soluble salts accumulate and raise osmotic stress on seeds and seedlings. Acidic soil does not produce a white salt crust, and high organic matter or earthworm activity do not cause such symptoms.

Question 40Soil and Soil Management

In a soil, the cation exchange capacity is determined mainly by which component?

  1. Clay and humus Correct answer.
  2. Soil water alone
  3. Soil air
  4. Sand and gravel

Explanation

Cation exchange capacity depends on negatively charged surfaces, which are supplied chiefly by clay minerals and humus. Sand and gravel have very little surface charge, and soil air and water do not provide exchange sites. Hence clay and humus govern the capacity.

Question 41Soil and Soil Management

A farmer wants to reduce nitrate loss from a sandy field during the rainy season. Which combination of practices is most suitable?

  1. Split nitrogen application with cover cropping Correct answer.
  2. Continuous flood irrigation without drainage
  3. Single large application of nitrogen before heavy rain
  4. Bare fallow with deep ploughing

Explanation

Sandy soils have low exchange capacity, so nitrate is easily leached. Splitting nitrogen doses matches supply to crop demand, and a cover crop takes up residual nitrate, reducing loss. A single large dose before rain, bare fallow, or continuous flooding all increase leaching or waterlogging.

Question 42Soil and Soil Management

Two soils have the same texture but one has higher organic matter. Which statement best predicts their relative behaviour?

  1. Both soils behave identically because texture is the same
  2. The organic-rich soil will have a lower water-holding capacity
  3. The organic-rich soil has higher exchange capacity and better aggregation Correct answer.
  4. The organic-rich soil has lower exchange capacity and poorer aggregation

Explanation

Organic matter adds negatively charged surfaces and binds particles into stable aggregates, so the organic-rich soil has higher exchange capacity and better structure. Texture alone does not fix these properties. The organic-rich soil also holds more water, not less.

Question 43Soil and Soil Management

Why does continuous monocropping of a cereal without legumes gradually reduce soil nitrogen availability?

  1. Harvested grain removes nitrogen while no biological fixation replaces it Correct answer.
  2. Harvesting grain adds nitrogen to the soil
  3. Cereals fix more nitrogen than legumes
  4. Cereal roots convert nitrate into clay

Explanation

Each harvested cereal crop exports nitrogen in the grain, and cereals do not fix atmospheric nitrogen. Without legumes or adequate fertiliser, the nitrogen balance becomes negative over time. Cereals do not fix nitrogen, and harvesting removes rather than adds nutrients.

Question 44Soil and Soil Management

A soil is tilled repeatedly to a fine tilth and left bare. Which outcome is most likely over several seasons?

  1. Decline in organic matter and increased surface crusting Correct answer.
  2. Permanent increase in cation exchange capacity
  3. Rapid build-up of humus and stable aggregates
  4. Elimination of the need for fertiliser

Explanation

Frequent tillage aerates the soil and accelerates the microbial oxidation of organic matter, while bare soil is exposed to raindrop impact that forms surface crusts. Humus and aggregation therefore decline rather than build up. Exchange capacity falls with organic matter and fertiliser needs do not disappear.

Question 45Crop Production and Management

Which crop is a kharif season crop in Haryana, normally sown with the arrival of monsoon rains in June–July?

  1. Paddy Correct answer.
  2. Mustard
  3. Wheat
  4. Gram

Explanation

Kharif crops are sown at the onset of the south-west monsoon and harvested in autumn; paddy, bajra, maize and cotton are typical kharif crops of Haryana. Wheat, mustard and gram are sown in the rabi season after October.

Question 46Crop Production and Management

In crop production terminology, the practice of growing two or more crops together in the same field in a definite row proportion is called:

  1. Fallow cropping
  2. Shifting cultivation
  3. Intercropping Correct answer.
  4. Sole cropping

Explanation

Intercropping places two or more crops in the same field simultaneously in definite rows, for example maize with cowpea, so that land and light are used more efficiently. Sole cropping means only one crop is grown in the field at a time.

Question 47Crop Production and Management

Seed rate for a crop is best expressed in which unit?

  1. Plants per kilogram
  2. Litres per hectare
  3. Kilograms per hectare Correct answer.
  4. Kilograms per litre

Explanation

Seed rate is the quantity of seed needed to sow one hectare, so it is expressed as kilograms per hectare. It depends on seed size, germination percentage and the recommended plant population.

Question 48Crop Production and Management

Which implement is used for primary tillage to break and invert the soil to a depth of about 15–20 cm?

  1. Patela
  2. Mouldboard plough Correct answer.
  3. Leveling board
  4. Seed drill

Explanation

The mouldboard plough is a primary tillage implement that cuts, lifts and inverts a furrow slice, burying weeds and stubble. Patela and leveling boards are secondary tillage tools for clod breaking and smoothing.

Question 49Crop Production and Management

The critical stage of irrigation for wheat, when water shortage causes the greatest yield loss, is:

  1. Tillering initiation
  2. Milking stage
  3. Dough stage
  4. Crown root initiation Correct answer.

Explanation

Crown root initiation, about 20–25 days after sowing, is the most critical stage for irrigation in wheat because crown roots form then and moisture stress at this point sharply reduces tillering and yield. Other stages also need water but are less damaging if briefly stressed.

Question 50Crop Production and Management

A farmer applies 120 kg of urea to one hectare. Approximately how much nitrogen does this supply? (Urea contains about 46% N.)

  1. 65 kg N
  2. 120 kg N
  3. 55 kg N Correct answer.
  4. 46 kg N

Explanation

Nitrogen supplied equals the product quantity multiplied by its N percentage, so 120 kg × 0.46 = 55.2 kg N. The remaining mass of urea is mainly carbon, oxygen and hydrogen.