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CUET Agriculture study materials
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CUET Agriculture practice questions

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Question 1Agriculture (domain subject)

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

  1. Reduced microbial activity in the rhizosphere
  2. Soil pH buffering against alkalinity
  3. Bulk density increase through compaction
  4. Water-holding capacity and cation exchange capacity Correct answer.

Explanation

Farmyard manure adds organic matter, which raises both water-holding capacity and cation exchange capacity in coarse-textured soils. Organic colloids retain moisture and exchangeable nutrients that sandy soils otherwise lose to leaching.

Question 2Agriculture (domain subject)

In crop rotation, a legume is included mainly because of which contribution to the following cereal crop?

  1. Deep tillage that breaks a hardpan layer
  2. Biological nitrogen fixation through rhizobia in root nodules Correct answer.
  3. Rapid removal of soil phosphorus from the profile
  4. Production of allelopathic compounds that kill weeds

Explanation

Legumes form symbiotic associations with rhizobia, which fix atmospheric nitrogen in root nodules and leave residual nitrogen in the soil. The following cereal benefits from this nitrogen credit, reducing fertilizer requirement.

Question 3Agriculture (domain subject)

A farmer wants to control weeds in a standing paddy crop without disturbing the crop canopy. Which practice best fits this requirement?

  1. Inter-row cultivation with a tractor cultivator
  2. Selective post-emergence herbicide application Correct answer.
  3. Deep ploughing after crop establishment
  4. Flood fallowing before sowing

Explanation

In a standing paddy crop, selective post-emergence herbicides target weeds without mechanical disturbance to the crop canopy or root system. Mechanical options are impractical once the field is flooded and the crop is established.

Question 4Agriculture (domain subject)

Which of the following is the primary role of a pollinator such as the honeybee in oilseed crop production?

  1. Absorption of micronutrients from the soil solution
  2. Fixation of atmospheric nitrogen in the soil
  3. Decomposition of crop residues in the field
  4. Transfer of pollen from anther to stigma to enable fertilization Correct answer.

Explanation

Pollinators carry pollen from the anther to the stigma, enabling fertilization and seed or fruit set. In cross-pollinated oilseeds this transfer directly raises yield and seed quality.

Question 5Agriculture (domain subject)

A crop shows interveinal chlorosis on older leaves while veins remain green, and the symptom appears first on lower leaves. Which nutrient deficiency is most consistent with this pattern?

  1. Iron
  2. Calcium
  3. Boron
  4. Magnesium Correct answer.

Explanation

Magnesium is mobile in the plant, so deficiency appears first on older leaves as interveinal chlorosis because the plant redistributes magnesium to young tissue. Iron and calcium are immobile and show symptoms on young leaves first.

Question 6Agriculture (domain subject)

Which irrigation method is most suitable for a widely spaced orchard on undulating land with limited water supply?

  1. Drip irrigation Correct answer.
  2. Furrow irrigation along the slope
  3. Basin flooding of the whole plot
  4. Border strip flooding

Explanation

Drip irrigation delivers water directly to the root zone with high application efficiency, which suits orchards, undulating terrain, and limited water supply. Flooding methods waste water and are poorly suited to uneven land.

Question 7Agriculture (domain subject)

A seed lot has 90 percent purity and 80 percent germination. What is its germination percentage adjusted for purity, expressed as pure live seed percentage?

  1. 85 percent
  2. 72 percent Correct answer.
  3. 90 percent
  4. 80 percent

Explanation

Pure live seed percentage is calculated as purity percentage multiplied by germination percentage divided by 100, giving 90 × 80 / 100 = 72 percent. This value reflects the proportion of the lot that is viable pure seed.

Question 8Agriculture (domain subject)

Which practice best reduces post-harvest losses of freshly harvested grains stored in a farm godown?

  1. Mixing fresh wet grain with dry grain to equalize moisture
  2. Drying grain to safe moisture content before storage Correct answer.
  3. Sealing undried grain in airtight bins to exclude insects
  4. Storing grain in moist gunny bags to prevent breakage

Explanation

Drying to safe moisture content limits fungal growth and insect multiplication during storage, which are the main causes of post-harvest loss. Airtight sealing of undried grain can trap moisture and promote spoilage.

Question 9Agriculture (domain subject)

Which of the following describes the correct sequence of operations in conservation agriculture?

  1. Minimum soil disturbance, permanent soil cover, and crop diversification Correct answer.
  2. Flood irrigation, bare fallow, and annual deep ploughing
  3. Deep tillage, residue burning, and continuous monocropping
  4. Repeated ploughing, removal of all residues, and sole cropping

Explanation

Conservation agriculture rests on three linked principles: minimum mechanical soil disturbance, permanent organic soil cover, and diversification of species through rotation or intercropping. Together they protect soil structure and organic matter.

Question 10Agriculture (domain subject)

A farmer applies urea to a flooded paddy field by surface broadcasting. Which nitrogen loss pathway is most increased by this practice?

  1. Immobilization by soil fauna
  2. Denitrification of nitrate in the subsoil
  3. Ammonia volatilization Correct answer.
  4. Nitrate leaching to groundwater

Explanation

Urea hydrolyses to ammonium at the flooded soil surface, and surface broadcasting raises pH and ammonia loss to the atmosphere. Incorporating urea into the reduced soil layer limits volatilization.

Question 11Agriculture (domain subject)

Which insect order includes the majority of serious defoliating caterpillars that attack field crops?

  1. Coleoptera
  2. Lepidoptera Correct answer.
  3. Orthoptera
  4. Hemiptera

Explanation

Lepidoptera includes moths and butterflies, whose larval stages are caterpillars and include many major defoliators of field crops. Hemiptera are mainly sap-sucking bugs, and Coleoptera and Orthoptera are beetles and grasshoppers.

Question 12Agriculture (domain subject)

Which control strategy is an example of biological control of a crop pest?

  1. Deep summer ploughing to expose pupae
  2. Spraying a broad-spectrum organophosphate insecticide
  3. Release of Trichogramma egg parasitoids in the field Correct answer.
  4. Burning crop residues after harvest

Explanation

Biological control uses living natural enemies such as parasitoids, predators, or pathogens to suppress pests. Releasing Trichogramma wasps, which parasitize pest eggs, is a classic example.

Question 13Agriculture (domain subject)

A soil test reports a pH of 5.2 for a field to be sown with a pH-sensitive cereal. Which amendment is most appropriate to raise the pH?

  1. Elemental sulphur
  2. Aluminium sulphate
  3. Ammonium sulphate
  4. Agricultural lime Correct answer.

Explanation

Agricultural lime, mainly calcium carbonate, neutralizes soil acidity and raises pH toward the target range for acid-sensitive crops. Sulphur and acidifying fertilizers lower pH further.

Question 14Agriculture (domain subject)

Which of the following is the correct botanical family of wheat?

  1. Fabaceae
  2. Brassicaceae
  3. Solanaceae
  4. Poaceae Correct answer.

Explanation

Wheat belongs to the grass family Poaceae, which includes cereals such as rice, maize, and barley. Fabaceae are legumes, Solanaceae include potato and tomato, and Brassicaceae are crucifers.

Question 15Agriculture (domain subject)

A farmer wants to produce hybrid seed of a self-pollinated crop on a small plot. Which technique is most appropriate?

  1. Random mixing of seed from two varieties
  2. Hand emasculation followed by controlled pollination Correct answer.
  3. Open pollination in an isolated field
  4. Natural cross-pollination by wind alone

Explanation

In self-pollinated crops, controlled crossing requires removing anthers from the female parent before dehiscence and applying pollen from the chosen male parent. Open pollination or seed mixing does not give defined hybrids.

Question 16Agriculture (domain subject)

Which factor most strongly determines the water requirement of a crop during its critical growth stage?

  1. Depth of ploughing before sowing
  2. Reference evapotranspiration and crop coefficient Correct answer.
  3. Seed rate and row spacing alone
  4. Soil colour and slope aspect

Explanation

Crop water requirement is estimated as reference evapotranspiration multiplied by the crop coefficient for that growth stage. Soil colour, seed rate, and ploughing depth do not directly determine evapotranspiration demand.

Question 17Agriculture (domain subject)

Which statement correctly describes the difference between complete and incomplete flowers?

  1. A complete flower lacks a pedicel; an incomplete flower has a pedicel
  2. A complete flower is always bisexual; an incomplete flower is always unisexual
  3. A complete flower has only stamens and carpels; an incomplete flower has petals only
  4. A complete flower has sepals, petals, stamens, and carpels; an incomplete flower lacks at least one of these Correct answer.

Explanation

A complete flower bears all four whorls: calyx, corolla, androecium, and gynoecium. An incomplete flower is missing one or more of these whorls, though it may still be bisexual.

Question 18Agriculture (domain subject)

Which measure best protects a sloping agricultural field from rill erosion during heavy monsoon rains?

  1. Contour bunding with vegetative cover Correct answer.
  2. Continuous bare fallow during the rainy season
  3. Removal of all crop residues after harvest
  4. Clean cultivation along the slope

Explanation

Contour bunds slow runoff along the contour, and vegetative cover protects the soil surface from raindrop impact and sheet flow. Together they reduce rill formation on sloping land.

Question 19Agriculture (domain subject)

In a rice-wheat cropping system, which practice most helps in managing the herbicide-resistant Phalaris minor problem in wheat?

  1. Continuous use of the same herbicide every season
  2. Rotating herbicide modes of action and using stale seedbed Correct answer.
  3. Flooding the wheat field after sowing
  4. Increasing the same herbicide dose every year

Explanation

Resistance management relies on rotating herbicide modes of action and integrating cultural practices such as a stale seedbed to reduce weed emergence. Repeating the same herbicide selects for resistant populations.

Question 20Agriculture (domain subject)

Which of the following best explains why hybrid maize yields more than open-pollinated varieties?

  1. Absence of genetic recombination in hybrids
  2. Heterosis expressed in the first filial generation Correct answer.
  3. Greater resistance to all pests by definition
  4. Superior seed size of hybrid lots

Explanation

Hybrid maize exploits heterosis, or hybrid vigour, expressed in the F1 generation from crossing inbred lines. This advantage depends on producing fresh F1 seed each season.

Question 21Agriculture (domain subject)

A farmer notices wilting at midday even when soil moisture is adequate, and the vascular tissue of a wilted plant shows brown discolouration. Which cause is most likely?

  1. Nitrogen deficiency
  2. Herbicide drift from a nearby field
  3. Sunscald on the fruit surface
  4. Vascular wilt pathogen such as Fusarium Correct answer.

Explanation

Vascular wilt pathogens colonize xylem vessels, causing brown discolouration and blocking water transport, so plants wilt despite adequate soil moisture. Nitrogen deficiency and sunscald do not cause vascular browning.

Question 22Agriculture (domain subject)

Which of the following is the most appropriate method for estimating the plant population of a crop in a field?

  1. Weighing the harvested produce of the whole field
  2. Quadrant sampling at random points and extrapolation Correct answer.
  3. Visual estimation from a moving vehicle
  4. Counting plants along one field edge only

Explanation

Random quadrat sampling gives an unbiased estimate of plant density that can be extrapolated to the field area. Edge counts and visual estimates introduce bias, and harvested weight measures yield rather than population.

Question 23Agriculture (domain subject)

In a dairy enterprise, which measure best improves the fat content of milk through feeding management?

  1. Feeding high levels of non-protein nitrogen alone
  2. Reducing roughage to near zero
  3. Increasing water intake alone
  4. Feeding balanced rations with adequate fibre and energy Correct answer.

Explanation

Milk fat synthesis depends on balanced energy and adequate effective fibre that supports rumen fermentation and acetate production. Very low roughage or excess non-protein nitrogen depresses fat content.

Question 24Agriculture (domain subject)

Which of the following correctly pairs an agricultural implement with its primary function?

  1. Seed drill with placing seed at a set depth and spacing Correct answer.
  2. Rotavator with winnowing chaff from grain
  3. Combine harvester with sowing seed in rows
  4. Mouldboard plough with threshing harvested grain

Explanation

A seed drill meters seed and places it at a controlled depth and row spacing for uniform establishment. Threshing, sowing, and winnowing are performed by other machines.

Question 25Agriculture (domain subject)

Which of the following is the best example of an integrated nutrient management practice on a mixed farm?

  1. Combining inorganic fertilizer with compost and green manure based on soil test Correct answer.
  2. Applying the maximum possible dose of urea every season
  3. Burning crop residues and relying solely on chemical fertilizer
  4. Leaving the field fallow without any nutrient input for years

Explanation

Integrated nutrient management combines organic sources such as compost and green manure with mineral fertilizers, guided by soil test values, to sustain yields and soil health. Single-source or no-input approaches are unbalanced.

Question 26Agriculture (domain subject)

Which cereal crop is described as a long-day plant whose vernalization requirement must be satisfied before floral initiation in winter types?

  1. Wheat Correct answer.
  2. Pearl millet
  3. Sorghum
  4. Maize

Explanation

Winter wheat requires exposure to low temperature (vernalization) during early vegetative growth before it can initiate flowering, and long days accelerate heading. The other cereals listed are short-day or day-neutral warm-season crops without a true vernalization requirement.

Question 27Agriculture (domain subject)

In a soil profile, which horizon is typically the zone of maximum accumulation of illuvial clay and sesquioxides?

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

Explanation

The B horizon is the subsoil zone where leached materials such as clay, iron and aluminium oxides accumulate (illuviation). The A horizon is the zone of eluviation and organic enrichment, while the C horizon is weathered parent material.

Question 28Agriculture (domain subject)

Which soil structure type is most favourable for root penetration and aeration in a well-drained agricultural topsoil?

  1. Massive
  2. Platy
  3. Columnar
  4. Granular Correct answer.

Explanation

Granular (crumb) structure consists of small, rounded aggregates with abundant pores, giving good aeration, drainage and root growth. Platy, massive and columnar structures restrict water movement and root penetration.

Question 29Agriculture (domain subject)

A farmer wants to sow a crop with a seed rate of 100 kg per hectare in rows 20 cm apart. Which implement is most appropriate for this sowing?

  1. Disc harrow
  2. Mouldboard plough
  3. Seed drill Correct answer.
  4. Leveller

Explanation

A seed drill places seed in rows at a controlled depth and rate, matching the specified row spacing and seed rate. Harrows, ploughs and levellers are tillage or land-shaping implements and do not meter seed.

Question 30Agriculture (domain subject)

Which plant nutrient is a constituent of chlorophyll and is therefore essential for the green colour and photosynthetic capacity of leaves?

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

Explanation

Magnesium is the central atom of the chlorophyll molecule, so deficiency causes interveinal chlorosis in older leaves. Potassium, sulphur and calcium serve other functions such as enzyme activation, protein synthesis and cell wall structure.

Question 31Agriculture (domain subject)

Which insect pest is a stem borer that attacks paddy by boring into the tiller base, causing dead hearts in the vegetative stage?

  1. Rice leaf folder
  2. Green leafhopper
  3. Yellow stem borer Correct answer.
  4. Brown planthopper

Explanation

Yellow stem borer larvae bore into the stem near the base, killing the central shoot and producing the characteristic dead heart. Planthoppers and leafhoppers are sap-sucking pests, and the leaf folder damages leaves by folding and scraping them.

Question 32Agriculture (domain subject)

Which fungal disease of wheat is characterised by orange-brown powdery pustules on the leaves that rub off on the fingers?

  1. Leaf rust Correct answer.
  2. Bacterial blight
  3. Loose smut
  4. Karnal bunt

Explanation

Leaf rust produces orange-brown uredinial pustules on leaf surfaces that release powdery spores when rubbed. Smut and bunt replace grain with black spore masses, and bacterial blight causes water-soaked lesions rather than powdery pustules.

Question 33Agriculture (domain subject)

Which farm animal is a ruminant that ferments feed in a four-chambered stomach, allowing it to digest roughage efficiently?

  1. Poultry
  2. Cattle Correct answer.
  3. Horse
  4. Pig

Explanation

Cattle are true ruminants with a four-chambered stomach (rumen, reticulum, omasum, abomasum) where microbial fermentation digests fibrous roughage. Pigs and poultry are monogastric, and the horse is a hindgut fermenter with a single-chambered stomach.

Question 34Agriculture (domain subject)

A field has a soil bulk density of 1.4 g per cubic centimetre and a particle density of 2.6 g per cubic centimetre. What is the approximate porosity of the soil?

  1. 54 percent
  2. 46 percent Correct answer.
  3. 86 percent
  4. 26 percent

Explanation

Porosity equals one minus the ratio of bulk density to particle density, so 1 minus (1.4 divided by 2.6) equals 0.46, or about 46 percent. This calculation shows the fraction of soil volume occupied by pore space.

Question 35Agriculture (domain subject)

A crop requires 8 mm of water per day and the effective root zone holds 120 mm of available water. If irrigation is applied when 50 percent of available water is depleted, what is the approximate irrigation interval?

  1. 15 days
  2. 8 days Correct answer.
  3. 30 days
  4. 3 days

Explanation

Fifty percent depletion of 120 mm equals 60 mm of allowable deficit. Dividing 60 mm by the 8 mm daily use gives about 7.5, or roughly 8 days between irrigations.

Question 36Agriculture (domain subject)

In genetics, a cross between two heterozygous tall pea plants (Tt x Tt) gives progeny in which the ratio of tall to dwarf plants is expected to be:

  1. 2 to 1
  2. 3 to 1 Correct answer.
  3. 1 to 1
  4. 9 to 1

Explanation

A monohybrid cross of two heterozygotes yields a genotypic ratio of 1 TT to 2 Tt to 1 tt. Since tall is dominant, three of four plants are tall and one is dwarf, giving a 3 to 1 phenotypic ratio.

Question 37Agriculture (domain subject)

A farmer wants to control weeds in a broadleaf crop without harming the crop. Which herbicide type is most suitable?

  1. Selective herbicide Correct answer.
  2. Non-selective herbicide
  3. Soil sterilant
  4. Fumigant

Explanation

Selective herbicides kill target weeds while leaving the crop relatively unharmed, which is the basis of safe weed control in a growing crop. Non-selective herbicides, sterilants and fumigants are not appropriate for this purpose.

Question 38Agriculture (domain subject)

Which process converts atmospheric nitrogen into ammonia using the nitrogenase enzyme within legume root nodules?

  1. Nitrification
  2. Biological nitrogen fixation Correct answer.
  3. Ammonification
  4. Denitrification

Explanation

Biological nitrogen fixation uses nitrogenase in symbiotic rhizobia within legume nodules to reduce atmospheric dinitrogen to ammonia. Nitrification and ammonification act on soil nitrogen forms, and denitrification returns nitrogen to the atmosphere.

Question 39Agriculture (domain subject)

Which cropping practice involves growing two or more crops simultaneously in the same field in a definite row arrangement?

  1. Fallowing
  2. Sole cropping
  3. Intercropping Correct answer.
  4. Sequence cropping

Explanation

Intercropping is the simultaneous cultivation of two or more crops in the same field with a definite planting pattern. Sole cropping involves one crop, sequence cropping grows crops one after another, and fallowing leaves land uncropped.

Question 40Agriculture (domain subject)

A crop shows purple discolouration of older leaves and stunted growth, with adequate soil moisture and nitrogen. Which nutrient deficiency is most likely?

  1. Nitrogen
  2. Iron
  3. Phosphorus Correct answer.
  4. Boron

Explanation

Phosphorus deficiency often causes purplish discolouration of older leaves and poor root and shoot growth. Nitrogen deficiency causes general yellowing, iron deficiency causes interveinal chlorosis of young leaves, and boron deficiency affects growing points.

Question 41Agriculture (domain subject)

Which method of plant propagation uses a portion of stem with buds that is detached from the parent and planted to form a new plant?

  1. Grafting
  2. Cuttage Correct answer.
  3. Layering
  4. Budding

Explanation

Cutting (cuttage) uses detached stem, root or leaf portions that regenerate roots and shoots. Layering keeps the stem attached while it roots, and grafting and budding join a scion to a rootstock.

Question 42Agriculture (domain subject)

Which storage practice is most effective for preventing insect infestation of stored wheat grain without chemical treatment?

  1. Keeping grain at high moisture
  2. Storing in a damp room
  3. Hermetic storage in airtight containers Correct answer.
  4. Storing in open gunny bags

Explanation

Hermetic storage in airtight containers depletes oxygen and raises carbon dioxide, killing or suppressing insects without chemicals. Open bags, high moisture and damp storage all favour insect multiplication and mould.

Question 43Agriculture (domain subject)

In a crop rotation, which sequence best helps to break the life cycle of a soil-borne pathogen that survives on a specific host?

  1. Increasing host plant density
  2. Growing the same host crop repeatedly
  3. Rotating with a non-host crop Correct answer.
  4. Continuous monocropping

Explanation

Rotating with a non-host crop deprives the pathogen of its host, reducing inoculum in the soil and breaking the disease cycle. Repeated cropping of the host, monocropping and higher host density all favour pathogen build-up.

Question 44Agriculture (domain subject)

Which type of tillage is best suited to conserve soil moisture and crop residues on an erosion-prone field?

  1. Zero tillage Correct answer.
  2. Repeated disc harrowing
  3. Deep ploughing
  4. Summer deep ploughing

Explanation

Zero tillage leaves crop residues on the surface, reducing evaporation, runoff and erosion while conserving soil moisture. Deep ploughing and repeated harrowing bury residues and expose soil to erosion and moisture loss.

Question 45Agriculture (domain subject)

A farmer wants to estimate the yield of a crop before harvest from a small representative area. Which approach is most appropriate?

  1. Weigh the entire field
  2. Estimate from a single border row
  3. Harvest a random quadrat and extrapolate Correct answer.
  4. Guess from plant height

Explanation

Harvesting a randomly placed representative quadrat and extrapolating to the field area gives an unbiased yield estimate. Weighing the whole field is impractical before harvest, border rows are unrepresentative, and plant height alone is unreliable.

Question 46Agriculture (domain subject)

A soil test shows a pH of 8.4 with high exchangeable sodium and poor infiltration. Which amendment is most appropriate?

  1. Single superphosphate
  2. Lime
  3. Urea
  4. Gypsum Correct answer.

Explanation

Sodic soils with high exchangeable sodium and high pH are reclaimed by applying gypsum, which supplies calcium to replace sodium on the exchange complex. Lime raises pH and is used for acidic soils, while urea and superphosphate are fertilisers, not reclaiming agents.

Question 47Agriculture (domain subject)

A farmer observes that a foliar-applied herbicide failed to control weeds although the dose was correct. Which factor most likely explains the failure?

  1. Applying at the recommended weed stage
  2. Application under drought stress with closed stomata and thick cuticle Correct answer.
  3. Using a calibrated sprayer
  4. Spraying during active weed growth with a surfactant

Explanation

Drought stress thickens the leaf cuticle and closes stomata, reducing herbicide absorption and translocation, so control fails even at the correct dose. Active growth, surfactant use, calibration and correct timing all favour herbicide efficacy.

Question 48Agriculture (domain subject)

In a breeding programme, a breeder wants to select superior genotypes from a segregating population while controlling environmental variation. Which design is most appropriate?

  1. Completely randomised design without replication
  2. Randomised complete block design Correct answer.
  3. Observational survey without controls
  4. Single-plant observation without replication

Explanation

A randomised complete block design groups experimental units into blocks that account for environmental variation, allowing valid comparison of genotypes. Unreplicated or uncontrolled designs confound genetic differences with environmental effects.

Question 49Agriculture (domain subject)

A dairy farmer wants to improve milk yield by improving the ration. Which principle is most important in formulating the ration?

  1. Balancing energy, protein, minerals and fibre to meet requirements Correct answer.
  2. Feeding only green fodder without concentrates
  3. Restricting water intake
  4. Maximising the quantity of a single feed

Explanation

A balanced ration supplies energy, protein, minerals, vitamins and adequate fibre in proportions that meet the animal's requirements for maintenance and production. Single-feed diets, overfeeding one ingredient or water restriction reduce yield and health.

Question 50Agriculture (domain subject)

Which integrated pest management decision is most appropriate when a pest population is below the economic threshold level?

  1. Spray on a fixed calendar schedule
  2. Increase pesticide dose above the label rate
  3. Apply a broad-spectrum insecticide immediately
  4. Use cultural and monitoring practices without chemical spraying Correct answer.

Explanation

When pest numbers are below the economic threshold, chemical control is not justified; monitoring and cultural measures are used to prevent build-up. Immediate broad-spectrum spraying, above-label doses and calendar spraying increase costs and resistance without benefit.