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Maharashtra SSC Agriculture Pre-Voc/NSQF study materials
Maharashtra SSC Agriculture Pre-Voc/NSQF study resources

Maharashtra SSC Agriculture Pre-Voc/NSQF practice questions

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Question 1Introduction to Agriculture and Crop Production Basics

Which branch of agriculture deals mainly with the scientific cultivation of field crops such as jowar, bajra and cotton?

  1. Horticulture
  2. Apiculture
  3. Agronomy Correct answer.
  4. Sericulture

Explanation

Agronomy is the branch of agriculture concerned with the production and management of field crops, including cereals, pulses, oilseeds and fibre crops. Horticulture covers fruits, vegetables and flowers, while sericulture and apiculture deal with silk and honey bees respectively.

Question 2Introduction to Agriculture and Crop Production Basics

A farmer in Vidarbha wants to grow a crop that fixes atmospheric nitrogen through root nodules. Which crop should be selected?

  1. Onion
  2. Soybean Correct answer.
  3. Wheat
  4. Sugarcane

Explanation

Leguminous crops such as soybean host Rhizobium bacteria in root nodules, which convert atmospheric nitrogen into a usable form and enrich soil fertility. Wheat, sugarcane and onion are non-legumes and cannot fix nitrogen in this way.

Question 3Introduction to Agriculture and Crop Production Basics

Which soil type, formed from lava, is dark in colour and especially suitable for cotton cultivation in Maharashtra?

  1. Black soil Correct answer.
  2. Sandy soil
  3. Saline soil
  4. Laterite soil

Explanation

Black soil, also called regur, is formed from weathered basaltic lava and is rich in clay and lime, with high moisture retention that suits cotton. Its dark colour and self-ploughing nature are typical of the Deccan trap region.

Question 4Introduction to Agriculture and Crop Production Basics

In crop rotation, a farmer alternates a cereal with a pulse crop. What is the main agronomic advantage of this practice?

  1. Complete removal of weeds from the field
  2. Guaranteed higher market price for every crop
  3. Elimination of the need for irrigation
  4. Improved soil nitrogen and reduced pest build-up Correct answer.

Explanation

Rotating a cereal with a pulse restores nitrogen through legume symbiosis and breaks the life cycle of pests and diseases specific to one crop family. It does not remove the need for irrigation or guarantee prices, so those claims are overstated.

Question 5Introduction to Agriculture and Crop Production Basics

Which of the following is a kharif crop commonly sown with the onset of the south-west monsoon in Maharashtra?

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

Explanation

Kharif crops are sown at the beginning of the monsoon and harvested in autumn; bajra is a typical kharif millet. Wheat, gram and mustard are rabi crops grown in the cooler post-monsoon season.

Question 6Introduction to Agriculture and Crop Production Basics

A seed lot shows 90 percent germination and is to be sown in a field where the recommended plant population is 100 plants per square metre. What is the minimum number of seeds required per square metre?

  1. About 111 seeds Correct answer.
  2. About 180 seeds
  3. About 90 seeds
  4. About 100 seeds

Explanation

The seed rate must be adjusted upward to compensate for failed germination. Dividing the desired population by the germination fraction gives 100 divided by 0.90, which is approximately 111 seeds per square metre.

Question 7Introduction to Agriculture and Crop Production Basics

Which practice involves ploughing the land and turning the soil before sowing to improve aeration and root penetration?

  1. Mulching
  2. Tillage Correct answer.
  3. Winnowing
  4. Threshing

Explanation

Tillage is the mechanical manipulation of soil through ploughing, harrowing and levelling to prepare a seedbed. Mulching covers the soil surface, while threshing and winnowing are post-harvest operations.

Question 8Introduction to Agriculture and Crop Production Basics

A farmer applies farmyard manure to a field before sowing. Which nutrient-supplying role does this organic manure chiefly perform?

  1. Raising soil pH sharply to neutralise acidity at once
  2. Acting as a pesticide that kills all soil insects
  3. Supplying organic matter that improves soil structure and releases nutrients slowly Correct answer.
  4. Providing a concentrated immediate dose of nitrogen only

Explanation

Farmyard manure is a bulky organic manure that adds humus, improves water-holding capacity and structure, and releases nutrients gradually as it decomposes. It is not a concentrated single-nutrient fertiliser and does not act as a broad-spectrum insecticide.

Question 9Introduction to Agriculture and Crop Production Basics

Which irrigation method delivers water drop by drop directly to the root zone and saves water compared with flood irrigation?

  1. Furrow irrigation
  2. Flood irrigation
  3. Drip irrigation Correct answer.
  4. Basin irrigation

Explanation

Drip irrigation applies water slowly and directly near the plant roots through emitters, greatly reducing evaporation and deep percolation losses. Flood, furrow and basin methods distribute water over the soil surface and generally use more water.

Question 10Introduction to Agriculture and Crop Production Basics

Which of these is a major abiotic factor that can reduce crop yield in rainfed areas of Maharashtra?

  1. Presence of Rhizobium in root nodules
  2. Prolonged dry spell during the flowering stage Correct answer.
  3. Use of certified quality seed
  4. Application of recommended doses of fertiliser

Explanation

Abiotic stresses are non-living environmental factors such as drought, heat and salinity. A prolonged dry spell at flowering causes flower drop and poor grain filling, sharply reducing yield, whereas the other options are beneficial inputs.

Question 11Introduction to Agriculture and Crop Production Basics

A farmer notices that a crop's leaves turn yellow between the veins while the veins remain green. Which nutrient deficiency is most likely?

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

Explanation

Interveinal chlorosis, where tissue between veins yellows while veins stay green, is a classic symptom of magnesium deficiency because magnesium is mobile and central to chlorophyll. Nitrogen deficiency usually yellows older leaves uniformly, and potassium and phosphorus deficiencies show different symptoms.

Question 12Introduction to Agriculture and Crop Production Basics

Which of the following is an example of a plant protection measure based on biological control?

  1. Releasing Trichogramma wasps to parasitise pest eggs Correct answer.
  2. Burning crop residue in the field
  3. Deep ploughing to bury weeds
  4. Spraying a broad-spectrum chemical insecticide

Explanation

Biological control uses living natural enemies such as parasitoid wasps, predators or pathogens to suppress pests. Trichogramma wasps lay eggs inside pest eggs, reducing the pest population without chemical sprays.

Question 13Introduction to Agriculture and Crop Production Basics

Why is certified seed preferred over seed saved from the previous harvest for a commercial crop?

  1. It is resistant to every possible pest
  2. It has assured genetic purity, germination and freedom from seed-borne disease Correct answer.
  3. It always gives a higher market price than other seed
  4. It needs no irrigation during the crop season

Explanation

Certified seed is produced under a seed certification programme and tested for genetic purity, germination percentage and seed health, giving reliable field performance. It does not guarantee prices, remove irrigation needs or confer universal pest resistance.

Question 14Introduction to Agriculture and Crop Production Basics

Which crop is grown mainly for its fibre, which is used by the textile industry?

  1. Cotton Correct answer.
  2. Groundnut
  3. Tur
  4. Sugarcane

Explanation

Cotton is cultivated primarily for lint, the fibre that is spun into yarn for textiles. Groundnut and tur are grown for oil and pulse respectively, and sugarcane is grown for sugar.

Question 15Introduction to Agriculture and Crop Production Basics

In the context of crop production, what does the term 'cropping intensity' express?

  1. The number of crops raised on the same land in one agricultural year Correct answer.
  2. The total weight of grain harvested from one hectare
  3. The depth to which the field is ploughed
  4. The percentage of seeds that germinate in the field

Explanation

Cropping intensity measures how many crops are harvested from the same piece of land within a year, often expressed as a percentage of the net sown area. It is a measure of land-use efficiency, not of yield weight, ploughing depth or germination.

Question 16Introduction to Agriculture and Crop Production Basics

A farmer wants to reduce soil erosion on a sloping field. Which practice is most directly suited to this purpose?

  1. Flood irrigation across the field
  2. Contour bunding along the slope Correct answer.
  3. Continuous clean cultivation without any cover
  4. Removal of all vegetation from the field

Explanation

Contour bunding creates small earthen barriers along the contour lines, slowing runoff and allowing water to infiltrate, which reduces soil loss on slopes. Removing vegetation or leaving soil bare accelerates erosion.

Question 17Introduction to Agriculture and Crop Production Basics

Which of the following correctly pairs a crop with the part of the plant that is mainly harvested for food?

  1. Carrot - modified root Correct answer.
  2. Spinach - modified root
  3. Potato - fruit
  4. Cauliflower - seed

Explanation

Carrot is a root vegetable, and the edible portion is the swollen taproot. Spinach is grown for leaves, potato is a stem tuber, and cauliflower is harvested for its flower head.

Question 18Introduction to Agriculture and Crop Production Basics

A farmer applies urea to a standing crop and then irrigates lightly. What is the main reason for applying irrigation immediately after urea top-dressing?

  1. To kill weeds growing between the crop rows
  2. To increase the phosphorus content of the soil
  3. To dissolve the urea and carry nitrogen into the root zone before it is lost as ammonia gas Correct answer.
  4. To lower the soil temperature permanently

Explanation

Urea hydrolyses on the soil surface and can lose nitrogen as ammonia gas, especially on warm, moist surfaces. Light irrigation dissolves the granules and moves nitrogen into the root zone, improving uptake and reducing volatilisation loss.

Question 19Introduction to Agriculture and Crop Production Basics

Which agricultural implement is primarily used for breaking clods and levelling the soil after primary ploughing?

  1. Chaff cutter
  2. Harrow Correct answer.
  3. Sprayer
  4. Seed drill

Explanation

A harrow is a secondary tillage implement that breaks clods, pulverises soil and helps level the field after the primary ploughing. A seed drill sows seed, a sprayer applies plant protection chemicals, and a chaff cutter chops fodder.

Question 20Introduction to Agriculture and Crop Production Basics

A farmer observes that a crop grown after a previous crop of the same family suffers from severe soil-borne disease. Which explanation best fits this observation?

  1. The crop has stopped performing photosynthesis
  2. The soil has become permanently alkaline due to the previous crop
  3. The seed rate used was lower than recommended
  4. The pathogen survives in soil and crop residues and multiplies on the same host Correct answer.

Explanation

Repeated cultivation of crops from the same family allows host-specific pathogens to survive in residue and soil and build up inoculum, a problem known as a monoculture effect. Rotating with an unrelated crop breaks this cycle and reduces disease pressure.

Question 21Introduction to Agriculture and Crop Production Basics

Which of the following is the correct sequence of operations in crop production from land preparation to storage?

  1. Sowing - ploughing - harvesting - weeding - storage - threshing
  2. Threshing - sowing - ploughing - weeding - harvesting - storage
  3. Harvesting - ploughing - sowing - storage - weeding - threshing
  4. Ploughing - sowing - weeding - harvesting - threshing - storage Correct answer.

Explanation

Land is first prepared by ploughing, then seed is sown, weeds are removed during crop growth, and the mature crop is harvested, threshed and finally stored. Any other order places a later operation before a prerequisite step.

Question 22Introduction to Agriculture and Crop Production Basics

Which of the following describes the main purpose of a nursery bed in vegetable cultivation?

  1. Raising healthy seedlings in a protected, well-managed area before transplanting Correct answer.
  2. Applying irrigation water to the main field
  3. Storing harvested grain safely after threshing
  4. Testing the soil for its nutrient content

Explanation

A nursery bed is a small, well-prepared and protected area where seeds are sown densely to raise healthy seedlings, which are later transplanted to the main field. This saves seed, allows careful care of young plants and improves establishment.

Question 23Introduction to Agriculture and Crop Production Basics

A farmer harvests 2,000 kg of paddy from a plot of 0.5 hectare. What is the yield per hectare?

  1. 500 kg per hectare
  2. 2,000 kg per hectare
  3. 4,000 kg per hectare Correct answer.
  4. 1,000 kg per hectare

Explanation

Yield per hectare equals total produce divided by the area in hectares. Dividing 2,000 kg by 0.5 hectare gives 4,000 kg per hectare, which is the standard way of expressing crop productivity.

Question 24Introduction to Agriculture and Crop Production Basics

Which practice is followed to protect stored grain from insect pests and moisture damage?

  1. Mixing soil with the grain before bagging
  2. Storing freshly harvested wet grain in open bags on the floor
  3. Keeping bags directly against damp walls
  4. Drying the grain to safe moisture and storing it in clean, airtight containers Correct answer.

Explanation

Grain must be dried to a safe moisture level before storage, since excess moisture encourages mould and insect attack. Clean, airtight containers or godowns with proper aeration further protect the produce from pests and dampness.

Question 25Soil Science, Soil Fertility and Conservation

In the Maharashtra SSC Agriculture curriculum, which soil particle size fraction is the smallest and contributes most to the soil's water-holding capacity and plasticity?

  1. Silt
  2. Sand
  3. Gravel
  4. Clay Correct answer.

Explanation

Clay particles are smaller than 0.002 mm and have a very large surface area relative to their mass, so they adsorb water strongly and give soil its sticky, plastic character. Sand and silt are coarser and hold far less water. Gravel is a coarse fragment, not a textural separate at all.

Question 26Soil Science, Soil Fertility and Conservation

A farmer's field has a soil pH of 5.2 and the crop is sensitive to acidity. Which amendment is most appropriate to raise the pH towards neutral?

  1. Elemental sulphur
  2. Lime (calcium carbonate) Correct answer.
  3. Gypsum
  4. Ammonium sulphate

Explanation

Lime, mainly calcium carbonate, neutralises soil acidity by reacting with hydrogen ions and raising pH towards neutral. Gypsum supplies calcium and sulphur but does not correct acidity. Elemental sulphur and ammonium sulphate both acidify soil further.

Question 27Soil Science, Soil Fertility and Conservation

Which soil organism is chiefly responsible for converting organic nitrogen into plant-available nitrate during aerobic decomposition in well-aerated soil?

  1. Mycorrhizal fungi
  2. Nitrifying bacteria Correct answer.
  3. Rhizobium bacteria
  4. Azotobacter bacteria

Explanation

Nitrifying bacteria such as Nitrosomonas and Nitrobacter oxidise ammonium to nitrite and then to nitrate in aerobic conditions, which is the nitrification step of the nitrogen cycle. Rhizobium and Azotobacter fix atmospheric nitrogen rather than producing nitrate from organic matter. Mycorrhizal fungi mainly assist nutrient uptake by roots.

Question 28Soil Science, Soil Fertility and Conservation

Which practice is a biological measure of soil conservation on a sloping field?

  1. Contour bunding with stone
  2. Levelling the field with a bulldozer
  3. Planting of vetiver grass strips along the contour Correct answer.
  4. Construction of a concrete check dam

Explanation

Biological or vegetative measures use living plant cover to slow runoff and bind soil, and vetiver strips planted along the contour are a classic example. Stone bunding and check dams are mechanical or engineering measures. Bulldozer levelling is a land-shaping operation, not a vegetative conservation measure.

Question 29Soil Science, Soil Fertility and Conservation

In the context of soil fertility, what is meant by the term 'available nutrient'?

  1. The nutrient stored in crop residues after harvest
  2. The portion of a nutrient in a form that plant roots can absorb during the growing season Correct answer.
  3. The total quantity of a nutrient locked in soil minerals
  4. The nutrient content present in applied fertiliser before it dissolves

Explanation

An available nutrient is the fraction in soil solution or on exchange sites that roots can take up during the crop season, which is what matters for fertiliser recommendation. Total nutrient content includes unavailable mineral-bound forms and is not a guide to immediate supply. Fertiliser content and residue nutrients describe other pools.

Question 30Soil Science, Soil Fertility and Conservation

Which of the following is classified as a macronutrient in plant nutrition, required in relatively large amounts?

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

Explanation

Magnesium is one of the six macronutrients, together with nitrogen, phosphorus, potassium, calcium and sulphur, and is central to chlorophyll. Zinc, boron and molybdenum are micronutrients needed only in small quantities.

Question 31Soil Science, Soil Fertility and Conservation

A soil sample shows 45 percent sand, 35 percent silt and 20 percent clay. Using the standard textural triangle, into which textural class does this soil fall?

  1. Loam Correct answer.
  2. Sandy loam
  3. Silty clay loam
  4. Sandy clay

Explanation

A sample with roughly equal proportions of sand, silt and clay, with sand slightly dominant, plots in the central loam region of the textural triangle. Loam is characterised by a balanced mixture that gives good workability and aeration. Clay percentages high enough for clay classes are far above 20 percent.

Question 32Soil Science, Soil Fertility and Conservation

A farmer applies 100 kg of urea to one hectare. Approximately how much nitrogen does this supply, given that urea contains about 46 percent nitrogen?

  1. 100 kg N
  2. 46 kg N Correct answer.
  3. 64 kg N
  4. 23 kg N

Explanation

The nitrogen content of a fertiliser is found by multiplying the quantity applied by the percentage nutrient content. Here 100 kg multiplied by 0.46 gives approximately 46 kg of nitrogen. The other values do not follow from the stated percentage.

Question 33Soil Science, Soil Fertility and Conservation

Which soil structure type is most desirable for good aeration, drainage and root penetration in a cultivated field?

  1. Granular (crumb) structure Correct answer.
  2. Single grain
  3. Platy structure
  4. Massive structure

Explanation

Granular or crumb structure consists of small, rounded aggregates with abundant pore space between them, favouring aeration, drainage and root growth. Single grain means loose particles with no aggregation, platy structure is layered and impedes vertical movement, and massive structure is a dense unbroken mass.

Question 34Soil Science, Soil Fertility and Conservation

Which conservation measure is specifically designed to reduce the velocity of runoff water and trap soil on a long, moderate slope by following the land contour?

  1. Summer fallowing
  2. Burning of crop residues
  3. Deep ploughing
  4. Contour bunding Correct answer.

Explanation

Contour bunding builds small earthen ridges along the contour so that runoff is intercepted and slowed, allowing water to infiltrate and soil to settle. Deep ploughing, fallowing and residue burning do not intercept runoff and can increase erosion risk.

Question 35Soil Science, Soil Fertility and Conservation

Which cation is mainly responsible for the dispersion of clay and the poor physical condition of sodic soils?

  1. Hydrogen
  2. Calcium
  3. Sodium Correct answer.
  4. Magnesium

Explanation

When sodium occupies a high proportion of the exchange complex, clay particles repel one another and disperse, destroying aggregates and making the soil hard and impermeable. Calcium and magnesium promote flocculation and stable structure. Hydrogen is associated with acidity rather than sodicity.

Question 36Soil Science, Soil Fertility and Conservation

A legume crop such as soybean is grown in rotation with cereals mainly to improve soil fertility through which process?

  1. Reduction of soil pH to release potassium
  2. Symbiotic nitrogen fixation in root nodules Correct answer.
  3. Enhanced leaching of sodium from the profile
  4. Increased phosphorus solubilisation from rock phosphate

Explanation

Legumes form nodules with Rhizobium bacteria that fix atmospheric nitrogen into forms the plant can use, and the residual nitrogen benefits the following cereal. They do not solubilise rock phosphate or deliberately acidify soil, and they are not grown to leach sodium.

Question 37Soil Science, Soil Fertility and Conservation

Which irrigation practice best helps to prevent the build-up of salts in the root zone of a crop grown in a semi-arid area?

  1. Applying excess water to leach salts below the root zone with adequate drainage Correct answer.
  2. Applying small frequent light irrigations only
  3. Using saline water without any drainage provision
  4. Irrigating only at the seedling stage

Explanation

In semi-arid regions evaporation concentrates salts near the surface, so a leaching fraction of extra water applied with good drainage carries salts below the root zone. Light frequent irrigations without leaching leave salts to accumulate. Limited irrigation or saline water without drainage worsens the problem.

Question 38Soil Science, Soil Fertility and Conservation

Which of the following best describes the role of organic matter in improving soil fertility?

  1. It increases bulk density and reduces pore space
  2. It permanently fixes phosphorus in unavailable forms
  3. It removes all soil microorganisms from the root zone
  4. It supplies nutrients on decomposition and improves water-holding capacity and structure Correct answer.

Explanation

Organic matter releases nitrogen, phosphorus and other nutrients as it decomposes and improves aggregation, water-holding capacity and cation exchange capacity. It reduces rather than increases bulk density, and it supports rather than removes soil microbes.

Question 39Soil Science, Soil Fertility and Conservation

A farmer wants to know the lime requirement of an acid soil before applying lime. Which soil test is used directly to estimate this requirement?

  1. Available nitrogen by alkaline permanganate method
  2. Buffer pH (lime requirement) test Correct answer.
  3. Organic carbon by Walkley-Black method
  4. Electrical conductivity of the saturation extract

Explanation

The buffer pH or lime requirement test measures how much the soil resists a pH change and converts this into the quantity of lime needed to reach a target pH. Electrical conductivity measures salinity, while the nitrogen and organic carbon tests measure fertility parameters unrelated to neutralising acidity.

Question 40Soil Science, Soil Fertility and Conservation

Which statement correctly distinguishes soil erosion from soil conservation?

  1. Erosion and conservation are identical terms for soil formation
  2. Erosion is a form of irrigation, while conservation is a form of drainage
  3. Erosion is the wearing away and transport of soil, while conservation is the set of practices that protect soil from such loss Correct answer.
  4. Erosion is the addition of nutrients to soil, while conservation is their removal

Explanation

Soil erosion is the detachment and transport of soil particles by water or wind, whereas soil conservation refers to measures that prevent or reduce this loss. The two concepts are opposite in direction, and neither is a form of nutrient addition, soil formation, irrigation or drainage.

Question 41Soil Science, Soil Fertility and Conservation

A field has a very high soil pH of about 9.0 with a high exchangeable sodium percentage and poor infiltration. Which reclamation strategy is technically appropriate?

  1. Flood the field with saline water and allow it to evaporate
  2. Apply more sodium-based fertiliser to displace calcium
  3. Do nothing, because sodic soils cannot be reclaimed
  4. Apply elemental sulphur and leach with good-quality water after providing drainage Correct answer.

Explanation

Reclaiming a sodic soil requires replacing exchangeable sodium with calcium and then removing the sodium salt by leaching with good water, which needs adequate drainage. Gypsum is commonly used, and acidifying amendments such as elemental sulphur can also help. Adding sodium, evaporating saline water or abandoning the field does not address the sodicity.

Question 42Soil Science, Soil Fertility and Conservation

In a soil, the cation exchange capacity is 25 cmol per kg and the exchange complex is 60 percent saturated with calcium, 30 percent with magnesium and 10 percent with potassium. What does this composition suggest about the soil's condition?

  1. The soil is saline and needs leaching
  2. The soil is strongly acidic and needs lime
  3. The soil is dominated by calcium and magnesium, indicating generally favourable base status with no sodicity hazard Correct answer.
  4. The soil is highly sodic and needs gypsum

Explanation

Calcium and magnesium together occupy 90 percent of the exchange sites, with only potassium making up the rest and sodium effectively absent, so the base status is favourable and there is no sodicity problem. Sodicity, acidity and salinity cannot be inferred from this cation composition alone because sodium is negligible and pH and electrical conductivity are not given.

Question 43Soil Science, Soil Fertility and Conservation

A farmer in a high-rainfall Konkan region notices that applied potassium fertiliser is rapidly lost from the root zone. Which explanation best accounts for this?

  1. Potassium is volatilised as ammonia gas from the soil surface
  2. Potassium is converted to insoluble rock minerals within a single season
  3. High rainfall causes leaching of soluble potassium through a soil with low cation exchange capacity Correct answer.
  4. Potassium is fixed strongly by organic matter and cannot move at all

Explanation

In high-rainfall areas, soluble potassium not held on exchange sites is carried downward by percolating water, and a soil with low cation exchange capacity retains little of it. Potassium does not volatilise as ammonia and is not converted to rock minerals in one season. Organic matter holds rather than irreversibly fixes it.

Question 44Soil Science, Soil Fertility and Conservation

Two soils have the same clay content, but soil A is dominated by kaolinite and soil B by montmorillonite. Which comparison of their behaviour is correct?

  1. Both soils will have identical cation exchange capacity because clay content is the same
  2. Soil B will have a higher cation exchange capacity and show greater swelling and shrinkage than soil A Correct answer.
  3. Soil A will have a higher cation exchange capacity and swell more on wetting than soil B
  4. Soil A will retain more water and nutrients because kaolinite has a larger surface area

Explanation

Montmorillonite is a 2:1 expanding clay with a large surface area and high cation exchange capacity, so it swells and shrinks markedly on wetting and drying. Kaolinite is a 1:1 non-expanding clay with lower surface area and cation exchange capacity. Equal clay content does not mean equal behaviour because clay mineral type matters.

Question 45Plant Nutrition, Manures and Fertilizer Management

Which plant nutrient is classified as a primary macronutrient in the Maharashtra SSC agriculture syllabus?

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

Explanation

Nitrogen, phosphorus and potassium are the three primary macronutrients because crops absorb them in the largest quantities. Zinc, boron and molybdenum are micronutrients required only in traces. Nitrogen is therefore the only primary macronutrient listed.

Question 46Plant Nutrition, Manures and Fertilizer Management

Which element is described as a secondary macronutrient in crop nutrition?

  1. Chlorine
  2. Copper
  3. Iron
  4. Calcium Correct answer.

Explanation

Calcium, magnesium and sulphur form the secondary macronutrient group: crops need them in moderate amounts, less than N, P and K but far more than micronutrients. Iron, copper and chlorine are all micronutrients. Calcium is thus the only secondary nutrient among the choices.

Question 47Plant Nutrition, Manures and Fertilizer Management

Which fertilizer is the principal nitrogenous fertilizer used for top dressing in Maharashtra?

  1. Single superphosphate
  2. Urea Correct answer.
  3. Muriate of potash
  4. Gypsum

Explanation

Urea contains about 46 per cent nitrogen, the highest among common solid nitrogen fertilizers, and is widely used for top dressing of cereals and vegetables. Single superphosphate supplies phosphorus, muriate of potash supplies potassium, and gypsum supplies calcium and sulphur. Only urea is a nitrogenous fertilizer.

Question 48Plant Nutrition, Manures and Fertilizer Management

Farmyard manure is best described as which type of manure?

  1. Complex inorganic fertilizer
  2. Concentrated organic manure
  3. Bulky organic manure Correct answer.
  4. Straight phosphatic fertilizer

Explanation

Farmyard manure contains a large proportion of water and organic matter with low nutrient concentration, so it is classed as bulky organic manure and applied in tonnes per hectare. Oil cakes and bone meal are concentrated organic manures, while complex and straight fertilizers are inorganic products.

Question 49Plant Nutrition, Manures and Fertilizer Management

Which microorganism is mainly responsible for converting atmospheric nitrogen into ammonia in the root nodules of legumes?

  1. Rhizobium Correct answer.
  2. Nitrobacter
  3. Aspergillus
  4. Azotobacter

Explanation

Rhizobium bacteria live symbiotically in root nodules of legumes such as gram and soybean and fix atmospheric nitrogen into ammonia for the plant. Azotobacter is a free-living aerobic fixer, Aspergillus is a soil fungus, and Nitrobacter oxidizes nitrite to nitrate in nitrification.

Question 50Plant Nutrition, Manures and Fertilizer Management

A farmer applies urea to a standing crop. Which method places the fertilizer in the root zone and reduces nitrogen loss?

  1. Drilling or placement near the root zone Correct answer.
  2. Spraying on leaves
  3. Broadcasting on dry soil surface
  4. Mixing with irrigation water in open channels

Explanation

Placing urea in the soil near the root zone, such as by drilling or band placement followed by covering, reduces volatilization and leaching losses and puts nitrogen where roots can absorb it. Surface broadcasting on dry soil, leaf spraying, and open channel mixing all allow greater loss or uneven distribution.