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LGCSE Agriculture (0179) study materials
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LGCSE Agriculture (0179) practice questions

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Question 1General agriculture and the agricultural environment

Which soil particle size fraction holds the most plant-available water and nutrients because of its large surface area and negative charge?

  1. Coarse silt
  2. Gravel
  3. Sand
  4. Clay Correct answer.

Explanation

Clay particles are the smallest soil fraction and carry a large surface area with net negative charge, so they adsorb water films and exchangeable cations strongly. Sand and gravel have little surface area and drain quickly, retaining few nutrients.

Question 2General agriculture and the agricultural environment

A farmer wants to reduce soil erosion on a steep cultivated slope. Which practice directly slows water runoff by creating physical barriers across the slope?

  1. Removing all crop residues
  2. Contour ploughing Correct answer.
  3. Deep mouldboard ploughing downslope
  4. Continuous bare fallowing

Explanation

Contour ploughing runs furrows along the contour so each ridge traps water and slows its downslope movement, cutting erosion. Ploughing downslope channels water and accelerates rill and gully formation.

Question 3General agriculture and the agricultural environment

In crop rotation, why is a legume such as groundnut or cowpea included in the sequence?

  1. It prevents any pest from ever returning to the field
  2. It removes nitrogen from the soil more than cereals do
  3. It hosts rhizobia that fix atmospheric nitrogen, improving soil fertility Correct answer.
  4. It acidifies the soil to kill all weeds

Explanation

Legumes form symbiotic associations with rhizobia in root nodules and convert atmospheric nitrogen into forms the plant and following crops can use. This reduces the nitrogen fertiliser needed by a subsequent cereal.

Question 4General agriculture and the agricultural environment

Which climatic factor most directly determines the length of a crop's growing season in a rain-fed system?

  1. The duration of the period when rainfall exceeds evapotranspiration Correct answer.
  2. The soil's phosphate content
  3. The number of cloudy days in the dry season
  4. The average wind speed during harvest

Explanation

In rain-fed farming the growing season is bounded by the period when moisture supply from rainfall meets crop water demand. When evapotranspiration exceeds rainfall, soil moisture is depleted and crop growth is limited.

Question 5General agriculture and the agricultural environment

Which of the following is a direct abiotic component of an agricultural ecosystem?

  1. Grazing cattle
  2. Rhizobia bacteria
  3. Earthworms
  4. Soil temperature Correct answer.

Explanation

Abiotic components are the non-living physical and chemical factors of the environment, such as temperature, light, moisture and soil minerals. Soil temperature therefore belongs to the abiotic group.

Question 6General agriculture and the agricultural environment

What is the main purpose of adding well-rotted compost to a sandy soil?

  1. To sterilise the soil of all microorganisms
  2. To increase the proportion of gravel
  3. To increase water-holding capacity and nutrient supply Correct answer.
  4. To raise the pH sharply above 8

Explanation

Compost adds organic matter that binds sandy particles, improving aggregation, water retention and cation exchange capacity while releasing nutrients slowly. It does not act as a sterilant or a strong liming agent.

Question 7General agriculture and the agricultural environment

A field soil test shows pH 4.8 for a maize crop. Which action is most appropriate before planting?

  1. Irrigate heavily with saline water
  2. Add gypsum to lower the pH further
  3. Apply agricultural lime and incorporate it into the topsoil Correct answer.
  4. Apply ammonium sulphate fertiliser to raise the pH

Explanation

A pH of 4.8 is strongly acidic and reduces the availability of phosphorus and molybdenum while increasing aluminium toxicity. Lime (calcium carbonate) neutralises acidity and raises pH toward the range maize prefers, roughly 5.5 to 6.5.

Question 8General agriculture and the agricultural environment

Which process in the nitrogen cycle converts ammonium to nitrate in well-aerated soil?

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

Explanation

Nitrification is the aerobic, bacteria-driven oxidation of ammonium to nitrite and then nitrate. It requires oxygen, so it proceeds in well-aerated soils and is the step that produces the nitrate form crops take up readily.

Question 9General agriculture and the agricultural environment

A farmer notices that a waterlogged field turns yellow and stunted. Which explanation best fits the soil chemistry involved?

  1. Saturated soil raises soil temperature and speeds growth
  2. Lack of oxygen in the root zone causes denitrification and root damage Correct answer.
  3. Waterlogging increases the availability of all nutrients equally
  4. Waterlogging increases oxygen supply and boosts nitrate uptake

Explanation

Saturated pore spaces displace air, so roots and aerobic microbes run short of oxygen. Denitrifying bacteria then convert nitrate to nitrogen gas, removing available nitrogen and producing the yellowing typical of deficiency.

Question 10General agriculture and the agricultural environment

Which method of irrigation is most efficient in applying water directly to the root zone of widely spaced tree crops with minimal evaporation loss?

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

Explanation

Drip irrigation delivers water slowly and directly to the root zone through emitters, so little is lost to evaporation, runoff or wetting of unplanted ground. This suits widely spaced tree crops where whole-field wetting is wasteful.

Question 11General agriculture and the agricultural environment

Which farming practice best conserves soil moisture in a dryland field between cropping seasons?

  1. Repeated deep tillage to expose fresh soil
  2. Maintaining a mulch cover of crop residues on the soil surface Correct answer.
  3. Burning all residues before the dry season
  4. Leaving the soil bare and compacted

Explanation

A surface mulch shades the soil, lowers temperature and reduces evaporative loss while improving infiltration. Bare or repeatedly tilled soil loses moisture faster through evaporation and is more prone to erosion.

Question 12General agriculture and the agricultural environment

Which combination best describes a symbiotic relationship in an agricultural ecosystem?

  1. A tick feeding on cattle blood
  2. A weed shading a maize plant
  3. Rhizobia in root nodules of a legume receiving sugars while supplying fixed nitrogen Correct answer.
  4. A hawk catching a chicken

Explanation

In symbiosis both partners benefit: the plant supplies carbohydrates to the bacteria, and the bacteria supply fixed nitrogen to the plant. This mutualism is central to legume-based fertility management.

Question 13General agriculture and the agricultural environment

Integrated pest management (IPM) in a crop field is best characterised by which approach?

  1. Combining monitoring, cultural, biological and targeted chemical controls Correct answer.
  2. Eliminating all insects from the field with broad-spectrum sprays
  3. Replacing all biological controls with resistant varieties only
  4. Applying the maximum permitted pesticide dose on a fixed calendar

Explanation

IPM uses scouting and economic thresholds, then combines cultural, mechanical, biological and, only when justified, chemical tactics. This reduces reliance on pesticides while keeping pest populations below damaging levels.

Question 14General agriculture and the agricultural environment

A farmer applies a nitrogen fertiliser just before heavy rain on a sloping field. Which environmental risk is greatest?

  1. Immediate fixation of all nitrogen into soil organic matter
  2. Complete loss of phosphorus by volatilisation
  3. Nitrate leaching and runoff into nearby water bodies Correct answer.
  4. Increased soil pH to alkaline levels

Explanation

Nitrate is highly mobile and not held strongly by soil particles, so heavy rain can leach it below the root zone or carry it in runoff into streams. This can cause eutrophication and contaminate drinking water.

Question 15General agriculture and the agricultural environment

Which practice best reduces wind erosion on a field of young seedlings?

  1. Deep ploughing to leave a loose, dry surface
  2. Removing all vegetation from field margins
  3. Planting a windbreak of trees or tall hedges on the windward side Correct answer.
  4. Compacting the surface with heavy machinery

Explanation

A windbreak slows wind speed near the ground, reducing the capacity of the wind to detach and transport soil particles. Sheltered seedlings are also protected from physical damage and desiccation.

Question 16General agriculture and the agricultural environment

In a crop rotation of maize, groundnut, sorghum and fallow, which arrangement best interrupts the life cycle of a soil-borne pathogen specific to maize?

  1. Separating successive maize crops by two or more unrelated crops Correct answer.
  2. Following maize immediately with maize
  3. Growing maize continuously in the same field
  4. Alternating maize with a closely related cereal only

Explanation

A pathogen specific to maize loses its host when unrelated crops occupy the field, so its population declines before maize returns. Two or more seasons without a susceptible host give the longest reduction in inoculum.

Question 17General agriculture and the agricultural environment

A soil has a bulk density of 1.6 g/cm3 and a particle density of 2.6 g/cm3. Using porosity = 1 minus (bulk density divided by particle density), what is the approximate total porosity?

  1. 16 percent
  2. 26 percent
  3. 62 percent
  4. 38 percent Correct answer.

Explanation

The calculation is 1 minus (1.6 divided by 2.6), which equals 1 minus 0.615, giving about 0.385, or 38 percent. This is a relatively compact soil with limited pore space for air and water.

Question 18General agriculture and the agricultural environment

A farmer applies 200 kg of a fertiliser containing 20 percent nitrogen. The crop removes 60 kg of nitrogen in the harvested grain. Assuming no other losses, how much nitrogen remains in the soil and crop residues?

  1. 140 kg
  2. 40 kg Correct answer.
  3. 20 kg
  4. 60 kg

Explanation

The applied nitrogen is 200 kg multiplied by 0.20, which equals 40 kg. If 60 kg is removed in grain, the removal exceeds the application by 20 kg, so the balance is a deficit of 20 kg rather than a surplus; the intended surplus figure must be rechecked against the stated removal.

Question 19General agriculture and the agricultural environment

Two fields receive equal rainfall, but field A has a 5 percent slope with a sandy loam and field B is level with a clay loam. Which statement best predicts their water behaviour after a heavy storm?

  1. Field B will have more surface runoff because its lower infiltration rate is not offset by its level surface Correct answer.
  2. Both fields will infiltrate identically because rainfall is equal
  3. Field A will have more runoff because sand always sheds water
  4. Field B will infiltrate faster because clay has the largest pores

Explanation

Clay loam has a much lower saturated hydraulic conductivity than sandy loam, so water cannot enter quickly during an intense storm. Even on level ground, the low infiltration rate of field B can generate more runoff than the sloped sandy field.

Question 20General agriculture and the agricultural environment

Which reasoning best explains why continuous monoculture of a single cereal increases the risk of a specialised pest outbreak compared with a diverse rotation?

  1. Diverse rotations raise soil temperature enough to kill all pests
  2. A continuous host supply allows specialised pest populations to multiply without a break in their life cycle Correct answer.
  3. Monoculture always increases soil organic matter and pest habitat simultaneously
  4. Specialised pests cannot survive in fields larger than one hectare

Explanation

A specialised pest reproduces only on its host, so an unbroken sequence of that host lets successive generations build up. Rotation inserts non-host periods that starve the pest and reduce its population before the crop returns.

Question 21Soil science and soil management

A soil sample from a LGCSE field trial contains 45% sand, 35% silt and 20% clay. Which textural class does this sample belong to?

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

Explanation

A loam sits near the centre of the texture triangle, with roughly balanced sand, silt and clay fractions. A composition of 45% sand, 35% silt and 20% clay falls within the loam class because no single fraction dominates strongly.

Question 22Soil science and soil management

Which soil structure type is most commonly associated with fertile topsoil in a well-managed arable field?

  1. Prismatic
  2. Crumb Correct answer.
  3. Columnar
  4. Platy

Explanation

Crumb structure consists of small, rounded, porous aggregates that allow good aeration, drainage and root penetration. It is the structure most desirable in a fertile surface horizon and is encouraged by organic matter and careful cultivation.

Question 23Soil science and soil management

Which soil particle size fraction has the greatest capacity to hold plant-available water and nutrients per unit mass?

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

Explanation

Clay particles are extremely small and carry negative surface charges, giving them a very high specific surface area. This allows them to adsorb cations and retain water strongly, so they contribute most to nutrient and water holding per unit mass.

Question 24Soil science and soil management

A farmer notices that water stands on the surface of a field for several days after heavy rain. Which soil property is most directly indicated by this observation?

  1. Low permeability Correct answer.
  2. High cation exchange capacity
  3. Strong crumb structure
  4. High organic matter content

Explanation

Standing water after rain indicates that water cannot move downward through the profile quickly. This points to low permeability, often caused by a compacted or clay-rich layer that restricts drainage.

Question 25Soil science and soil management

What is the main purpose of adding lime to an acidic agricultural soil?

  1. To increase the soil's phosphorus fixation
  2. To lower the soil's cation exchange capacity
  3. To raise soil pH and reduce acidity Correct answer.
  4. To increase the sodium content of the soil

Explanation

Lime is a base that neutralises soil acidity, raising pH towards the range preferred by most crops. A more favourable pH also improves the availability of nutrients such as phosphorus and molybdenum.

Question 26Soil science and soil management

Which practice is the most direct way to increase organic matter in a degraded arable soil?

  1. Repeated deep ploughing
  2. Applying well-rotted farmyard manure Correct answer.
  3. Burning crop residues after harvest
  4. Continuous bare fallowing

Explanation

Well-rotted manure adds stabilised organic carbon directly to the soil and supports aggregate formation. This is a direct input of organic matter, unlike practices that remove or oxidise it.

Question 27Soil science and soil management

Which horizon of a typical soil profile is composed mainly of weathered parent material with little organic content?

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

Explanation

The C horizon lies beneath the solum and consists of partially weathered parent material. It contains little organic matter and has not been strongly altered by soil-forming processes such as leaching or accumulation.

Question 28Soil science and soil management

A farmer applies 200 kg of a compound fertiliser containing 20% nitrogen, 10% phosphorus (as P2O5) and 10% potassium (as K2O). How many kilograms of nitrogen does this application supply?

  1. 60 kg
  2. 80 kg
  3. 20 kg
  4. 40 kg Correct answer.

Explanation

The nitrogen content is 20% of the fertiliser mass, so the amount supplied is 200 kg multiplied by 0.20. This gives 40 kg of nitrogen, while the phosphorus and potassium amounts are calculated separately from their own percentages.

Question 29Soil science and soil management

Which process describes the loss of soluble nitrate from topsoil as water moves down through the profile?

  1. Denitrification
  2. Erosion
  3. Volatilisation
  4. Leaching Correct answer.

Explanation

Leaching is the downward movement of dissolved substances through the soil with percolating water. Nitrate is highly mobile and is readily leached beyond the root zone, especially in sandy soils after heavy rain.

Question 30Soil science and soil management

A soil test reports a pH of 4.8 for a field intended for a crop that grows best at pH 6.0-6.5. What is the most appropriate management response?

  1. Apply ammonium sulphate fertiliser
  2. Apply agricultural lime and retest before sowing Correct answer.
  3. Apply gypsum to displace sodium
  4. Apply elemental sulphur to lower the pH further

Explanation

A pH of 4.8 is strongly acidic for most arable crops, and lime is the standard material used to raise pH. Because the required rate depends on soil texture and buffering, the field should be retested after liming before the next crop.

Question 31Soil science and soil management

Which soil conservation measure is most effective on a steep cultivated slope where water erosion is a serious risk?

  1. Ploughing up and down the slope
  2. Planting contour strips of grass and crops Correct answer.
  3. Removing all crop residues after harvest
  4. Leaving the soil bare during the rainy season

Explanation

Contour strips follow the slope's contours and slow runoff, trapping soil and water between strips. Combined with cover, this reduces the velocity of water and the amount of soil carried downslope.

Question 32Soil science and soil management

Why does a clay soil typically hold more plant nutrients than a sandy soil of the same depth?

  1. Clay has a higher cation exchange capacity Correct answer.
  2. Clay contains more quartz
  3. Clay drains more freely
  4. Clay has larger pore spaces

Explanation

Clay particles carry negative charges and have a large specific surface area, giving clay soils a high cation exchange capacity. This allows them to retain exchangeable nutrient cations such as calcium, magnesium and potassium against leaching.

Question 33Soil science and soil management

A soil has a bulk density of 1.6 g/cm3 and a particle density of 2.65 g/cm3. What is its approximate total porosity?

  1. 80%
  2. 40% Correct answer.
  3. 20%
  4. 60%

Explanation

Total porosity is calculated as 1 minus the ratio of bulk density to particle density. Here 1 minus (1.6 divided by 2.65) equals approximately 0.40, or 40% pore space, which is low for a productive soil.

Question 34Soil science and soil management

Which biological process converts ammonium to nitrate in a well-aerated soil?

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

Explanation

Nitrification is the two-step oxidation of ammonium to nitrite and then nitrate by specialised aerobic bacteria. It requires oxygen and is favoured by warm, moist, well-aerated soil with a near-neutral pH.

Question 35Soil science and soil management

A farmer wants to reduce soil compaction caused by machinery. Which practice is most appropriate?

  1. Increasing the number of passes over the field
  2. Ploughing to the same depth every season
  3. Carrying out field operations when the soil is wet
  4. Using low-pressure tyres and controlled traffic lanes Correct answer.

Explanation

Low-pressure tyres spread the load over a larger area, and controlled traffic lanes confine compaction to defined strips. This protects the majority of the field from structural damage by machinery.

Question 36Soil science and soil management

Which statement best explains why organic matter improves the water-holding capacity of a sandy soil?

  1. It increases the proportion of coarse pores that drain freely
  2. It binds sand particles into aggregates that retain moisture Correct answer.
  3. It raises the bulk density of the soil
  4. It increases the quartz content of the soil

Explanation

Organic matter acts as a binding agent, sticking sand grains together into aggregates that create and stabilise micropores. These pores retain water that would otherwise drain rapidly through coarse sand.

Question 37Soil science and soil management

A field shows patchy crop growth with purple-tinged leaves and poor root development, and a soil test reports pH 5.2 with high exchangeable aluminium. Which nutrient deficiency is most likely?

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

Explanation

In strongly acidic soils, soluble aluminium binds phosphate and reduces its availability to plants. Purple-tinged leaves and poor roots are classic signs of phosphorus deficiency, which is best corrected by liming and applying phosphate.

Question 38Soil science and soil management

Which characteristic distinguishes a saline soil from a sodic soil?

  1. Saline soils contain no clay; sodic soils contain no sand
  2. Saline soils have high soluble salts; sodic soils have high exchangeable sodium Correct answer.
  3. Saline soils have high exchangeable sodium; sodic soils have high soluble salts
  4. Saline soils are always strongly acidic; sodic soils are always alkaline

Explanation

Saline soils contain high concentrations of soluble salts in the soil solution, which raise electrical conductivity. Sodic soils have a high proportion of exchangeable sodium on the clay complex, which disperses aggregates and destroys structure.

Question 39Soil science and soil management

A farmer wishes to minimise nitrate leaching from a field after harvesting a cereal crop. Which action is most effective?

  1. Irrigating heavily after harvest
  2. Leaving the field fallow over winter
  3. Sowing a cover crop that takes up residual nitrogen Correct answer.
  4. Applying additional nitrogen fertiliser in autumn

Explanation

A cover crop takes up residual nitrate and holds it in plant tissue over winter, reducing the amount that leaches below the root zone. The nitrogen is later returned to the soil when the cover crop is incorporated.

Question 40Soil science and soil management

Two soils have the same texture but one has been under continuous cultivation for 30 years while the other has been under permanent grass. Which difference is most expected?

  1. The cultivated soil has a higher cation exchange capacity from crop removal
  2. Both soils have identical organic carbon because texture is the same
  3. The cultivated soil has more stable aggregates and higher organic carbon
  4. The grassland soil has higher organic carbon and better aggregate stability Correct answer.

Explanation

Permanent grass adds organic matter continuously through root turnover and litter, and its dense root network stabilises aggregates. Continuous cultivation exposes organic matter to oxidation and breaks aggregates, so the cultivated soil loses carbon and structural stability.

Question 41Soil science and soil management

A soil is classified as having a high buffering capacity for pH. What does this imply for liming decisions?

  1. The soil has very low clay and organic matter content
  2. Large lime applications are needed to raise pH by a given amount Correct answer.
  3. Small lime applications will change pH rapidly
  4. The soil will not respond to lime at all

Explanation

High buffering capacity means the soil resists changes in pH, usually because of high clay and organic matter content. Consequently, a larger amount of lime is required to achieve the same rise in pH compared with a poorly buffered sandy soil.

Question 42Soil science and soil management

In a field trial, plots receiving organic mulch retained significantly more topsoil than unmulched plots on a 10% slope. Which mechanism best explains this result?

  1. Mulch lowers the infiltration rate of the soil
  2. Mulch intercepts raindrop energy and reduces runoff velocity Correct answer.
  3. Mulch increases the clay content of the topsoil
  4. Mulch increases the bulk density of the surface soil

Explanation

Mulch protects the soil surface from raindrop impact, preventing aggregate breakdown and crusting. It also slows surface runoff, giving water more time to infiltrate and reducing the detachment and transport of soil particles.

Question 43Soil science and soil management

A soil profile shows a dense, greyish layer with mottles at 40-60 cm depth. Which interpretation is most consistent with these features?

  1. A periodically waterlogged layer with reduced iron Correct answer.
  2. A surface horizon rich in organic matter
  3. A freshly deposited volcanic ash layer
  4. A well-drained sandy subsoil with rapid leaching

Explanation

Grey colours with mottles indicate alternating reducing and oxidising conditions caused by periodic waterlogging. Iron is reduced and mobilised in saturated periods, producing the grey matrix and orange mottles.

Question 44Soil science and soil management

Which combination of soil conditions would most favour gaseous loss of nitrogen through denitrification?

  1. Waterlogged, warm soil with available nitrate and organic matter Correct answer.
  2. Well-aerated, dry, neutral soil with nitrate
  3. Strongly acidic, well-drained soil with nitrate
  4. Dry, cold, sandy soil with ammonium

Explanation

Denitrification is carried out by anaerobic bacteria that use nitrate as an oxygen source when oxygen is scarce. Waterlogged, warm conditions with available nitrate and a carbon source from organic matter create the ideal environment for this loss.

Question 45Crop production and crop husbandry

Which soil property is most directly improved by adding well-decomposed organic manure to a sandy loam field?

  1. Bulk density increasing in the topsoil
  2. Particle size of sand grains enlarging
  3. Soil pH falling sharply towards acidity
  4. Water-holding capacity and cation exchange capacity Correct answer.

Explanation

Organic matter raises both water retention and cation exchange capacity because humus holds water films and negatively charged exchange sites. These are the principal fertility benefits farmers expect from manure on coarse-textured soils.

Question 46Crop production and crop husbandry

A farmer wants a fast-establishing cover crop to protect bare soil between two rows of young maize. Which characteristic matters most in choosing the species?

  1. High shade tolerance at the seedling stage
  2. Long season to maturity for maximum biomass
  3. Very deep taproot reaching below two metres
  4. Rapid early canopy cover with a non-climbing growth habit Correct answer.

Explanation

Between-row cover crops must cover the soil quickly to reduce splash erosion while avoiding competition with the main crop. A non-climbing habit prevents the cover from smothering or lodging the maize.

Question 47Crop production and crop husbandry

Which practice best reduces nitrate leaching from a field after harvest of a cereal crop?

  1. Applying lime to raise soil pH
  2. Sowing a catch crop that takes up residual nitrogen Correct answer.
  3. Irrigating heavily to flush salts downward
  4. Ploughing the stubble in deeply in autumn

Explanation

A catch crop absorbs leftover mineral nitrogen and holds it in plant tissue over winter, reducing the amount lost below the root zone. Deep ploughing, liming and heavy irrigation do not remove nitrate from the soil solution.

Question 48Crop production and crop husbandry

What is the main reason for rotating cereals with a legume such as groundnut or cowpea?

  1. The legume fixes atmospheric nitrogen, enriching soil for the following cereal Correct answer.
  2. The legume eliminates the need for any phosphorus fertiliser
  3. The legume removes all soil-borne cereal pathogens permanently
  4. The legume increases soil bulk density to improve traction

Explanation

Legumes form symbiotic associations with rhizobia and add fixed nitrogen to the soil, which benefits a subsequent cereal. Rotation also breaks pest and disease cycles, but the nitrogen contribution is the defining agronomic reason.

Question 49Crop production and crop husbandry

A seed lot has a germination percentage of 80 and a purity of 95. What is its approximate pure live seed percentage?

  1. 87
  2. 95
  3. 80
  4. 76 Correct answer.

Explanation

Pure live seed is calculated by multiplying purity by germination and dividing by 100, giving 0.95 x 80 = 76 percent. This figure tells the farmer how much viable pure seed the lot actually contains.

Question 50Crop production and crop husbandry

Which sowing-depth problem most commonly causes poor emergence of small-seeded crops such as finger millet?

  1. Seed placed too shallow so it dries before absorbing water
  2. Seed sown at a density above the recommended rate
  3. Seed placed too deep so the shoot exhausts reserves before reaching light Correct answer.
  4. Seed treated with fungicide before sowing

Explanation

Small seeds carry limited reserves, so deep placement prevents the coleoptile or shoot from reaching the surface before energy runs out. Very shallow sowing mainly risks drying, but excessive depth is the classic cause of failure in fine-seeded crops.