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NM Pesticide Applicator study materials
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NM Pesticide Applicator practice questions

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Question 1Pesticide Laws and Regulations

Under FIFRA, what is the legal effect of the directions for use printed on a pesticide label?

  1. They are legally binding; use inconsistent with the label is a violation. Correct answer.
  2. They may be waived by a licensed applicator in an emergency.
  3. They apply only when the product is classified as restricted use.
  4. They are recommendations that the applicator may adjust to local conditions.

Explanation

FIFRA makes it unlawful to use a pesticide in a manner inconsistent with its labeling, and this applies to all registered products, not just restricted-use pesticides. An individual applicator cannot waive label directions; emergency exceptions require a formal Section 18 exemption.

Question 2Pesticide Laws and Regulations

Which state agency administers pesticide product registration and applicator certification in New Mexico?

  1. New Mexico Energy, Minerals and Natural Resources Department
  2. New Mexico Department of Health
  3. New Mexico Department of Agriculture Correct answer.
  4. New Mexico Environment Department

Explanation

The New Mexico Pesticide Control Act assigns administration of pesticide registration, licensing, and certification to the New Mexico Department of Agriculture. Other state agencies may have related environmental or health roles, but NMDA is the pesticide regulatory authority.

Question 3Pesticide Laws and Regulations

Under certification rules, a private applicator is certified to do which of the following?

  1. Apply general-use pesticides only in and around a home.
  2. Supervise commercial applications for a pesticide dealer.
  3. Apply restricted-use pesticides on land they own or rent. Correct answer.
  4. Apply restricted-use pesticides for hire on a client's property.

Explanation

A private applicator is certified to use restricted-use pesticides on property they own or rent, or on their employer's agricultural land, without being hired as a commercial applicator. Applying pesticides for hire or supervising commercial work requires commercial certification.

Question 4Pesticide Laws and Regulations

When a noncertified person applies a restricted-use pesticide, federal rules require that the application be made:

  1. under a written contract filed with EPA.
  2. only if the pesticide is a general-use product.
  3. only after the noncertified person passes a closed-book exam.
  4. under the direct supervision of a certified applicator. Correct answer.

Explanation

Restricted-use pesticides may be applied by noncertified persons only under the direct supervision of a certified applicator. The certified applicator remains responsible for ensuring that label directions and supervision requirements are met.

Question 5Pesticide Laws and Regulations

A Section 18 exemption under FIFRA allows a state to do which of the following?

  1. Permanently register a pesticide for a minor crop.
  2. Waive all label requirements for a certified applicator.
  3. Permit temporary emergency use of an unregistered pesticide or use. Correct answer.
  4. Set a state tolerance that replaces the federal tolerance.

Explanation

Section 18 authorizes EPA to grant emergency exemptions for unregistered pesticide uses, or for unregistered products, for a limited period when no registered alternative is available. Permanent minor-crop uses are handled through other registration mechanisms, and tolerances are set under the food safety law.

Question 6Pesticide Laws and Regulations

A Section 24(c) special local need registration is used to:

  1. Add a state-specific use to a federally registered product. Correct answer.
  2. exempt a state from FIFRA labeling requirements.
  3. permit sale of a pesticide that failed federal registration.
  4. allow a dealer to relabel a product for a customer.

Explanation

Section 24(c) allows a state to register an additional use for a pesticide that is already federally registered, when the state documents a special local need. The product must still be federally registered, and the state registration does not exempt anyone from federal labeling requirements.

Question 7Pesticide Laws and Regulations

Under the Worker Protection Standard, agricultural employers must provide handlers with decontamination supplies:

  1. at the employer's main office, regardless of how far away it is.
  2. only at the end of the workday.
  3. within one-quarter mile, with soap, water, and towels. Correct answer.
  4. only when a pesticide spill occurs.

Explanation

The Worker Protection Standard requires that handlers have access to decontamination supplies, including soap, water, and single-use towels, within one-quarter mile of the work site. Supplies must be available during handling work, not only after an incident.

Question 8Pesticide Laws and Regulations

When a pesticide label does not state a re-entry interval for an agricultural use covered by the WPS, the minimum interval before workers may re-enter is:

  1. 12 hours Correct answer.
  2. 1 hour
  3. 4 hours
  4. 8 hours

Explanation

The Worker Protection Standard establishes a default re-entry interval of 12 hours when the labeling does not specify one for an agricultural use. The label may require a longer interval, and short-term entry exceptions are limited.

Question 9Pesticide Laws and Regulations

How long must a pesticide dealer keep records of restricted-use pesticide sales under federal regulations?

  1. 5 years
  2. 10 years
  3. 2 years Correct answer.
  4. 30 days

Explanation

Dealers must keep records of restricted-use pesticide sales for at least 2 years. The records must identify the product, the amount sold, and the certified purchaser.

Question 10Pesticide Laws and Regulations

Certified applicators who apply restricted-use pesticides must keep application records for at least how long under FIFRA?

  1. 2 years Correct answer.
  2. 1 year
  3. 7 years
  4. 6 months

Explanation

FIFRA requires certified applicators to keep records of restricted-use pesticide applications for at least 2 years. The records must include information such as the product, amount, date, and location of the application.

Question 11Pesticide Laws and Regulations

Under the WPS, how often must agricultural workers receive pesticide safety training?

  1. once at hire only
  2. at least every 12 months Correct answer.
  3. every 3 years
  4. every 5 years

Explanation

The Worker Protection Standard requires workers to be trained before they work in an area covered by the standard and at least every 12 months thereafter. Handlers are subject to the same annual training requirement.

Question 12Pesticide Laws and Regulations

Under the Federal Food, Drug, and Cosmetic Act, a pesticide residue on food is unlawful when:

  1. the pesticide is registered by EPA.
  2. the residue exceeds EPA's established tolerance. Correct answer.
  3. the product is labeled for agricultural use.
  4. the residue is detectable at any level.

Explanation

The Federal Food, Drug, and Cosmetic Act authorizes EPA to set tolerances, which are the maximum allowable pesticide residues in or on food. A residue above the tolerance, or a residue for which no tolerance exists, makes the food adulterated.

Question 13Pesticide Laws and Regulations

Who should a New Mexico applicator notify about a pesticide misuse incident that may harm people or the environment?

  1. The manufacturer's advertising department.
  2. The local pesticide dealer who sold the product.
  3. NMDA's pesticide program, plus 911 for emergencies. Correct answer.
  4. Only the property owner.

Explanation

The New Mexico Department of Agriculture administers the state pesticide program and receives reports of pesticide misuse. If people or the environment are in immediate danger, emergency responders should also be called.

Question 14Pesticide Laws and Regulations

Before a pesticide product may be sold or distributed in New Mexico, it must generally be:

  1. tested by the New Mexico Environment Department.
  2. approved by the county extension office.
  3. registered with the New Mexico Department of Agriculture. Correct answer.
  4. registered with EPA only.

Explanation

New Mexico requires pesticide products distributed in the state to be registered with the New Mexico Department of Agriculture, in addition to any federal EPA registration. County extension offices and the Environment Department do not perform pesticide product registration.

Question 15Pesticide Laws and Regulations

An Experimental Use Permit (EUP) issued by EPA allows:

  1. permanent registration of a product while data are pending.
  2. a dealer to sell unregistered pesticides to certified applicators.
  3. a state to ignore federal label directions for research.
  4. limited use of an unregistered pesticide, or a new use, for experimental purposes. Correct answer.

Explanation

An Experimental Use Permit authorizes limited use of an unregistered pesticide, or an unregistered use of a registered product, to gather data for research. It is not a route to permanent registration or a license to disregard label directions.

Question 16Pesticide Laws and Regulations

If a New Mexico regulation is more restrictive than the pesticide label, what must the applicator do?

  1. Apply for a federal waiver before every application.
  2. Choose either the label or the state rule.
  3. Follow the label because federal law always preempts state rules.
  4. Meet both the label and the stricter state rule. Correct answer.

Explanation

FIFRA permits states to impose restrictions that are more stringent than federal requirements. An applicator must comply with the label and with any stricter state rule, so meeting only one of them is not sufficient.

Question 17Pesticide Laws and Regulations

Which practice is consistent with pesticide container handling requirements?

  1. Triple-rinsing containers and disposing of them according to the label. Correct answer.
  2. Reusing containers for drinking water.
  3. Leaving containers at the application site for the landowner.
  4. Burning empty containers in the field.

Explanation

Pesticide containers should be triple-rinsed or pressure-rinsed as directed and then disposed of in the manner specified by the label. Containers must not be reused for food or water or abandoned at the application site.

Question 18Pesticide Laws and Regulations

Under CERCLA, a pesticide spill that releases a reportable quantity must be reported to which federal entity?

  1. The Occupational Safety and Health Administration
  2. The U.S. Department of Agriculture
  3. The Federal Trade Commission
  4. The National Response Center Correct answer.

Explanation

CERCLA requires releases of hazardous substances above reportable quantities to be reported to the National Response Center. State and local reporting requirements may also apply.

Question 19Pesticide Laws and Regulations

EPA may classify a pesticide as restricted use when it:

  1. is sold only in bulk containers.
  2. costs more than general-use products.
  3. poses unreasonable risks without extra restrictions. Correct answer.
  4. has a state registration only.

Explanation

A restricted-use classification is based on the pesticide's potential to cause unreasonable adverse effects on human health or the environment without additional restrictions. Cost, container size, and state-only registration are not classification criteria.

Question 20Pesticide Laws and Regulations

A certified commercial applicator sends a noncertified technician to apply a restricted-use pesticide. Which statement is correct?

  1. The certified applicator remains responsible for label compliance and supervision. Correct answer.
  2. The technician may supervise other noncertified applicators.
  3. No record of the application is required because the technician is not certified.
  4. Responsibility shifts entirely to the technician once the application begins.

Explanation

When a restricted-use pesticide is applied by a noncertified person, the certified applicator must provide direct supervision and remains accountable for compliance with the label. Responsibility is not transferred to the noncertified technician.

Question 21Pesticide Laws and Regulations

Which item is generally required in a record of a restricted-use pesticide application?

  1. The date, location, and amount of pesticide applied Correct answer.
  2. The full names of the applicator's immediate family members
  3. The applicator's home address
  4. The retail price paid by the customer

Explanation

Restricted-use application records must identify the product, amount applied, date, and location of the application, among other details. Personal information about the applicator's family or the customer's price is not part of the required record.

Question 22Pesticide Laws and Regulations

Which practice best meets pesticide storage requirements?

  1. Storing pesticides next to animal feed to keep them dry
  2. Keeping them in labeled original containers, locked away Correct answer.
  3. Transferring pesticides to unmarked beverage bottles
  4. Storing pesticides on the floor of a busy barn aisle

Explanation

Pesticides should be kept in their original labeled containers in a secured storage area away from food, feed, and people. Transferring products to unmarked containers or leaving them in traffic areas creates contamination and poisoning risks.

Question 23Pesticide Laws and Regulations

Which federal law governs the registration, labeling, and sale of pesticides?

  1. the Resource Conservation and Recovery Act, which governs solid and hazardous waste
  2. the Federal Insecticide, Fungicide, and Rodenticide Act Correct answer.
  3. the Safe Drinking Water Act, which protects public water systems
  4. the Clean Water Act, which regulates discharges into surface waters

Explanation

FIFRA is the federal statute that establishes pesticide registration, labeling, and sale requirements. The Clean Water Act, RCRA, and the Safe Drinking Water Act address other environmental programs.

Question 24Pesticide Laws and Regulations

Which law gives EPA authority to set tolerances for pesticide residues in food?

  1. Federal Food, Drug, and Cosmetic Act Correct answer.
  2. Emergency Planning and Community Right-to-Know Act
  3. FIFRA
  4. CERCLA

Explanation

The Federal Food, Drug, and Cosmetic Act provides the authority for EPA to establish tolerances, which are the maximum legal pesticide residues allowed in or on food. FIFRA governs registration and labeling, while CERCLA and EPCRA address release reporting and community right-to-know.

Question 25Pesticide Laws and Regulations

Under New Mexico pesticide law, a person who sells restricted-use pesticides at retail generally must:

  1. be a certified private applicator only.
  2. register each customer with EPA.
  3. hold a New Mexico pesticide dealer license. Correct answer.
  4. obtain a structural pest control license.

Explanation

New Mexico requires pesticide dealers who sell restricted-use products to be licensed by the state, in addition to complying with federal requirements. Dealer records and verification that the buyer is certified are also required.

Question 26Pesticide Laws and Regulations

Which state agency is the lead agency responsible for administering the New Mexico Pesticide Control Act, including registering pesticide products for sale and certifying applicators in the state?

  1. New Mexico Department of Health
  2. New Mexico Environment Department
  3. New Mexico State University Cooperative Extension Service
  4. New Mexico Department of Agriculture Correct answer.

Explanation

The New Mexico Pesticide Control Act designates the New Mexico Department of Agriculture as the lead agency for pesticide regulation in the state. NMDA registers pesticide products sold in New Mexico, certifies and licenses applicators, and enforces label and state rule compliance. Other state agencies administer separate environmental or public health programs.

Question 27Pesticide Laws and Regulations

Under FIFRA and New Mexico rules, a private applicator certificate authorizes the use of restricted-use pesticides mainly on which areas?

  1. Land the applicator or the applicator's employer owns or rents to produce an agricultural commodity Correct answer.
  2. Only land located within the county where the certificate was originally issued
  3. Property of commercial customers who have signed a written service agreement
  4. Any property in New Mexico, as long as the applicator holds a currently valid private certificate

Explanation

A private applicator is certified to apply restricted-use pesticides on land owned or rented by the applicator or the employer for the production of an agricultural commodity, and on adjacent areas as allowed. Applying restricted-use pesticides for hire on someone else's property requires commercial certification. The certificate is not limited to a single county.

Question 28Pesticide Laws and Regulations

An invasive pest outbreak occurs in a New Mexico county and no registered pesticide product is available to control it. Which mechanism allows EPA to permit the temporary use of an unregistered product for that emergency?

  1. A Section 18 emergency exemption Correct answer.
  2. A state-issued tolerance exemption
  3. An experimental use permit
  4. A Section 24(c) special local need registration

Explanation

FIFRA Section 18 authorizes EPA to exempt a pesticide from registration for a limited time and area when an emergency pest condition exists and no registered alternative is available. Section 24(c) adds a state-specific use to an already registered product, and an experimental use permit exists to generate data, not to resolve an emergency. Tolerance decisions rest with EPA and are not made by the state.

Question 29Pesticide Laws and Regulations

In New Mexico, a person who applies pesticides for hire on property owned by others must generally do which of the following?

  1. File an application report with EPA before each job
  2. Obtain written approval from the county Extension office
  3. Be licensed as a commercial applicator by NMDA Correct answer.
  4. Hold only a private applicator certificate issued by NMDA

Explanation

Applying pesticides for hire on another person's property is commercial application, which requires commercial applicator certification or licensing from the New Mexico Department of Agriculture; the business itself also needs a pesticide business license. A private certificate covers only the applicator's own or employer's agricultural land. Federal and county offices do not issue these state credentials.

Question 30Pesticide Laws and Regulations

Under FIFRA, which application of a registered pesticide is permitted even though the label does not specifically state it?

  1. Applying at a rate higher than the label allows when pest pressure is severe
  2. Applying the product in a manner the label expressly prohibits
  3. Applying at a rate below the labeled rate, unless the label forbids it Correct answer.
  4. Applying the product to a use site that does not appear anywhere on the label

Explanation

FIFRA provides that using a pesticide at a dosage, concentration, or frequency less than that specified on the label is not a use inconsistent with labeling, unless the label specifically prohibits such a lower rate. Using the product on an unlisted site, exceeding labeled rates, or acting against an express label prohibition is a violation of the statute and the label.

Question 31Pest Identification and Integrated Pest Management

Which statement best describes integrated pest management (IPM)?

  1. A method of eliminating every insect from a field regardless of the cost or the damage
  2. A decision process using monitoring, thresholds, and combined tactics Correct answer.
  3. A program that relies on the single most effective pesticide available for each pest
  4. A calendar-based spray schedule that applies pesticide to every acre on fixed dates

Explanation

IPM is a decision framework in which pests are identified and monitored, a threshold determines whether action is warranted, and the least risky effective mix of cultural, biological, mechanical, and chemical tactics is used. The emphasis is on decisions rather than on routine applications.

Question 32Pest Identification and Integrated Pest Management

A grower scouts a field and finds an average of 12 aphids per leaf. The action threshold is 20 aphids per leaf. What is the most appropriate IPM response?

  1. Apply a soil fumigant before planting to eliminate the entire aphid population
  2. Apply a broad-spectrum insecticide immediately to prevent any yield loss
  3. Switch to a calendar spray schedule for the rest of the season
  4. Continue monitoring and take no treatment action at this time Correct answer.

Explanation

Action thresholds are decision rules: treatment is justified only when the pest population reaches or exceeds the threshold. At 12 aphids per leaf the population is below the threshold of 20, so the correct response is to keep monitoring.

Question 33Pest Identification and Integrated Pest Management

Insects that pass through egg, nymph, and adult stages, with nymphs resembling the adults, have which type of development?

  1. Parthenogenetic development without mating
  2. Gradual (incomplete) metamorphosis Correct answer.
  3. Hypermetamorphosis, with several different larval forms
  4. Complete metamorphosis, including a pupal stage

Explanation

Gradual, or incomplete, metamorphosis has only egg, nymph, and adult stages, and the nymphs look like small versions of the adult. Complete metamorphosis, by contrast, adds a pupal stage and produces a larva that looks nothing like the adult.

Question 34Pest Identification and Integrated Pest Management

Stippling, leaf silvering, and distorted new growth are most typical of damage by pests with which mouthpart type?

  1. Chewing mouthparts that remove leaf tissue in chunks
  2. Sponging mouthparts that soak up liquids from surfaces
  3. Piercing-sucking mouthparts Correct answer.
  4. Siphoning mouthparts that draw nectar from flowers

Explanation

Piercing-sucking insects insert stylets and withdraw plant sap, which produces stippling, silvering, and curled or distorted new growth. Chewing insects remove tissue outright and leave holes and missing leaf area instead.

Question 35Pest Identification and Integrated Pest Management

Which characteristic is most useful for separating a grass weed from a broadleaf weed at the seedling stage?

  1. Leaves that are attached to the stem by petioles
  2. Net-like veins branching across the leaf surface
  3. A growing point located at the top of the plant
  4. Leaf veins that run parallel along the blade Correct answer.

Explanation

Grass leaves have parallel veins running lengthwise along the blade, and their stems are usually round. Broadleaf plants have net-like, branching veins and leaves commonly borne on petioles.

Question 36Pest Identification and Integrated Pest Management

The disease triangle model states that a plant disease epidemic requires a susceptible host, a pathogen, and what third factor?

  1. A vector insect that carries the pathogen between plants
  2. Environmental conditions favorable for disease Correct answer.
  3. An open wound through which the pathogen must enter
  4. A dense population of weed hosts growing nearby

Explanation

The disease triangle holds that disease occurs only when a susceptible host, a virulent pathogen, and favorable environmental conditions occur together. Breaking any one leg of the triangle prevents the epidemic.

Question 37Pest Identification and Integrated Pest Management

A lady beetle larva found feeding on aphids in an alfalfa field is best described as which of the following?

  1. A primary pest species that damages the crop
  2. A secondary pest that follows an outbreak
  3. A vector that spreads a plant pathogen
  4. A biological control agent Correct answer.

Explanation

Lady beetle larvae are predators of aphids and other soft-bodied insects, so they function as biological control agents that help suppress pest populations. They feed on the pest rather than on the crop.

Question 38Pest Identification and Integrated Pest Management

Which scouting pattern gives the most representative sample of pest density in a rectangular field?

  1. Walking a zigzag or W pattern across the field Correct answer.
  2. Sampling only the plants along the irrigation ditch
  3. Checking one large plant located in the exact center of the field
  4. Examining plants only in the first row near the field gate

Explanation

A zigzag or W pattern spreads samples across the field so that variation in soil, moisture, and pest distribution is represented. Sampling in a single spot over-represents local conditions.

Question 39Pest Identification and Integrated Pest Management

A pest has a lower development threshold of 50 degrees F. The daily maximum is 80 F and the daily minimum is 50 F. Using the simple average method, how many degree-days accumulate that day?

  1. 15 Correct answer.
  2. 5
  3. 30
  4. 65

Explanation

The simple average method averages the daily maximum and minimum and subtracts the lower threshold: (80 + 50) / 2 = 65, and 65 - 50 = 15 degree-days. When the minimum falls below the threshold, it is set to the threshold before averaging.

Question 40Pest Identification and Integrated Pest Management

A field has developed resistance to a particular herbicide. Which practice best slows further resistance development?

  1. Applying the same herbicide at a higher rate
  2. Mixing the herbicide with a surfactant to increase uptake
  3. Using the same herbicide more frequently during the season
  4. Rotating among herbicides with different modes of action Correct answer.

Explanation

Resistance management depends on reducing selection pressure on any single mode of action. Rotating among herbicides with different modes of action, along with nonchemical tactics, slows the selection of resistant biotypes.

Question 41Pest Identification and Integrated Pest Management

Releasing purchased predatory mites into a greenhouse to control spider mites is an example of which biological control approach?

  1. Classical (importation) biological control
  2. Conservation biological control that protects existing enemies
  3. Cultural biological control based on habitat modification
  4. Augmentation biological control Correct answer.

Explanation

Augmentation means releasing or increasing populations of natural enemies, such as purchased predatory mites, where too few are present to give adequate control. Conservation and classical approaches involve existing or newly imported enemies rather than periodic releases.

Question 42Pest Identification and Integrated Pest Management

Which of the following is a cultural control practice for a soilborne disease?

  1. Rotating to a nonhost crop for several years Correct answer.
  2. Releasing parasitic wasps into the crop
  3. Setting pheromone traps around the field border
  4. Applying a foliar fungicide after symptoms appear

Explanation

Crop rotation to a nonhost starves soilborne pathogens of their host and reduces inoculum in the field over time. It is a cultural practice that works without additional pesticide input.

Question 43Pest Identification and Integrated Pest Management

Installing fine mesh screens over greenhouse vents to keep out whiteflies is which type of pest control?

  1. Mechanical or physical control Correct answer.
  2. Chemical control using a residual insecticide
  3. Biological control using a released natural enemy
  4. Host plant resistance through plant breeding

Explanation

Screens are a physical barrier that excludes the pest from the crop, so the practice is classified as mechanical or physical control. Neither a pesticide nor a living organism is involved.

Question 44Pest Identification and Integrated Pest Management

Why does conserving natural enemies matter when choosing an insecticide?

  1. Natural enemies reduce the need for scouting the field
  2. Beneficial insects increase the pest's reproductive rate
  3. Natural enemies make the pest population more resistant to chemicals
  4. Broad-spectrum products can trigger secondary pest outbreaks Correct answer.

Explanation

Many insecticides are broad spectrum and kill predators and parasitoids along with the target pest. With natural enemies removed, previously minor pests such as mites or aphids can increase and require additional treatments.

Question 45Pest Identification and Integrated Pest Management

Root-knot nematode damage in a vegetable field most typically appears as which symptom pattern?

  1. Uniform stunting of every plant in the field at the same stage
  2. Irregular patches of stunted plants with galled roots Correct answer.
  3. Uniform yellowing that begins along the field edges
  4. Circular patches of dead plants that spread outward

Explanation

Root-knot nematodes invade roots and cause galls that disrupt water and nutrient uptake, producing irregular patches of stunted, yellowing plants. Digging affected plants reveals the galled roots that confirm the diagnosis.

Question 46Pest Identification and Integrated Pest Management

Which feature best distinguishes a vole from a mole in the field?

  1. Voles are active only at night; moles are active only by day
  2. Voles have long naked tails; moles have bushy tails
  3. Voles look like mice; moles have broad, shovel-like forefeet Correct answer.
  4. Voles have webbed feet and swim; moles do not

Explanation

Voles are compact, mouse-like rodents with short tails and small ears that travel in surface runways. Moles have broad, outward-facing forefeet with strong claws for digging and rarely come to the surface.

Question 47Pest Identification and Integrated Pest Management

Why must a perennial weed such as Canada thistle be managed differently from an annual weed?

  1. It regrows from underground roots and rhizomes Correct answer.
  2. It dies after producing seed in one growing season
  3. It has no root system below the soil surface
  4. It reproduces only by seed each year

Explanation

Perennial weeds such as Canada thistle regrow from rootstocks and rhizomes, so removing the top growth does not kill the plant. Effective programs combine systemic herbicides with repeated cultivation timed to deplete root reserves.

Question 48Pest Identification and Integrated Pest Management

A plant shows mosaic patterns, mottling, and stunted growth with no fungal growth or bacterial ooze. These symptoms are most consistent with which cause?

  1. A nutrient deficiency caused by low soil pH
  2. A fungal leaf spot pathogen spreading in wet weather
  3. A bacterial soft rot pathogen entering through wounds
  4. A virus infection spread by aphids and infected seed Correct answer.

Explanation

Mosaic, mottling, and stunting without fungal signs or bacterial ooze point to a virus, which is often moved by aphids or infected seed. Viruses cannot be cured in the field, so prevention and vector management are the main tools.

Question 49Pest Identification and Integrated Pest Management

Serpentine, whitish trails inside a leaf surface are characteristic of which pest group?

  1. Cutworms cutting seedlings at the soil line
  2. Aphids feeding on phloem
  3. Grubs feeding on roots
  4. Leafminer larvae feeding in the mesophyll Correct answer.

Explanation

Leafminer larvae feed between the upper and lower leaf surfaces and leave winding, whitish trails of emptied tissue. The trails are visible from above but do not break through the leaf surface.

Question 50Pest Identification and Integrated Pest Management

The economic injury level is best defined as which of the following?

  1. The lowest density causing damage equal to control cost Correct answer.
  2. The number of pests caught in a trap during one week
  3. The pest density at which a pesticide application always pays for itself
  4. The point at which a pest population begins to reproduce

Explanation

The economic injury level is the pest density at which the value of crop loss equals the cost of control; above that level, treatment is expected to be profitable. Action thresholds are set at or below this level for use in the field.