QUIZ 1 PESTS

What is agronomic pest management?

Managing organisms that damage crops while considering crop production and control decisions.

What is a plant pest?

Any organism that is noxious or harmful to plants.

What are five common plant pest groups?

Insects; diseases; weeds; nematodes; larger animals and birds.

About what fraction of potential food worldwide is lost to pests each year according to the lecture?

25%

About what percentage of potential food in the U.S. is lost to pests according to the lecture?

About 25%.

What is domestication of crops?

Selecting and breeding wild plants for useful agricultural traits such as higher yield.

How can domestication increase vulnerability to pests?

Breeding for yield can reduce natural pest resistance.

What is monoculture?

Growing one kind of crop over a wide area.

Why can monoculture increase pest problems?

Large areas of the same host favor survival and spread of crop-specific pests and diseases.

What is the clean-field approach?

Finding a pest and applying pesticide to kill it, rather than tolerating non-damaging pest levels.

What is a calendar spray program?

Applying pesticides on a schedule with little regard for pest population levels.

Why can routine pesticide use become a problem?

It increases costs, harms beneficial organisms, and selects for resistant pests.

What does IPM stand for?

Integrated Pest Management.

What is Integrated Pest Management (IPM)?

A combination of compatible crop and pest-control practices that keeps pests at sub-economic levels with minimal adverse effects on human health and the environment.

Does IPM aim to eliminate every pest?

No. It aims to keep pest populations below economically damaging levels.

What is the primary objective of IPM regarding chemical control?

Make maximum use of biological control, host-plant resistance, and cultural control before using chemical control.

What is population monitoring?

Scouting to estimate pest numbers and whether populations are increasing, decreasing, or stable.

What is crop rotation?

Changing from a susceptible crop to a resistant or tolerant crop to reduce the pest population.

Why does crop rotation help control disease?

Changing host crops reduces the availability of a suitable host for the disease organism.

What are resistant varieties?

Crop varieties selected or bred to resist or tolerate specific pests.

Why may resistant varieties be useful only for a limited time?

Pests may evolve new strains that overcome crop resistance or tolerance.

What is cultural control?

Adjusting agricultural practices such as tillage, planting dates, harvest dates, crop residue, and crop rotation to reduce pests.

Give three examples of cultural control.

Crop rotation; changing planting dates; destroying crop residue.

What is biological control?

Using natural enemies or other organisms to suppress pests.

What is chemical control?

Using chemical pesticides to reduce pest populations below economic levels.

Give three reasons chemicals are a last resort in IPM.

Cost; environmental and human health effects; pesticide resistance. They can also release secondary pests.

What is a secondary pest outbreak?

A previously minor pest increases after pesticide use disrupts competitors or natural enemies.

What is pesticide resistance?

Inherited ability of a pest population to survive pesticide treatments that previously controlled it.

What was the main reason agricultural pest-management philosophy changed according to the professor?

Insects developed resistance to insecticides.

What does DDT stand for?

Dichlorodiphenyltrichloroethane.

What book raised public awareness about pesticide effects in 1962?

Silent Spring by Rachel Carson.

What is biomagnification?

The increasing concentration of certain persistent chemicals up the food chain.

What is step 1 to solve a pest problem using IPM?

Identify the pest.

What is step 2 to solve a pest problem using IPM?

Determine infestation/damage levels and pest population dynamics.

What is step 3 to solve a pest problem using IPM?

Determine what, if any, control methods are available.

What is step 4 to solve a pest problem using IPM?

Evaluate benefits against risks and choose the effective method with the least environmental damage.

When is chemical treatment economically unjustified?

When the cost of control exceeds the expected economic benefit.

What are the three general characteristics of arthropods?

Segmented bodies; jointed appendages; exoskeleton made of chitin.

What are two identifying characteristics of an insect?

Three pairs of legs (six legs) and three body regions.

What are the three main insect body regions?

Head; thorax; abdomen.

Give two examples of insects.

Grasshopper and butterfly.

How many legs do spiders and mites have?

Eight legs.

How many leg pairs per body segment do centipedes typically have?

One pair per leg-bearing segment.

How many leg pairs per diplosegment do millipedes typically have?

Two pairs.

Which usually moves faster, a centipede or a millipede?

Centipede.

What is an exoskeleton?

A hard external skeleton that supports and protects an arthropod.

What substance gives the insect exoskeleton structure?

Chitin.

How does the insect exoskeleton conserve moisture?

A waxy outer layer reduces water loss.

Why must a growing insect molt?

Its rigid exoskeleton does not continuously stretch as the insect grows.

What is molting?

Shedding an old exoskeleton to allow growth.

What is an instar?

The developmental form or stage between molts.

What is a stadium?

The time period between molts.

What is the difference between instar and stadium?

Instar = developmental stage; stadium = time period between molts.

What is the epicuticle?

The outer waxy layer that reduces water loss and helps block foreign matter.

What is the procuticle?

The layer containing chitin and protein that provides body structure.

What is the epidermis (hypodermis) in the insect integument?

The inner living cell layer that secretes the cuticle.

What are the three thorax segments?

Prothorax; mesothorax; metathorax.

Where do insect legs attach?

To the thorax; one pair per thoracic segment.

Which two thorax segments generally bear wings in winged insects?

Mesothorax and metathorax.

What is the coxa?

The first leg segment connecting the leg to the thorax.

What is the basic order of insect leg segments from body outward?

Coxa; trochanter; femur; tibia; tarsus.

What are pulvilli?

Adhesive pads on insect feet, as in houseflies.

What is wing venation?

The pattern of wing veins used for insect identification.

How many abdominal segments may insects have?

Up to 11.

What are spiracles?

External openings of the insect respiratory system.

What are compound eyes?

Eyes made of many visual units that detect motion and may distinguish colors.

What are simple eyes (ocelli)?

Small eyes mainly involved in detecting light intensity.

Which mouthpart is similar to a tongue?

Hypopharynx.

What is the labrum?

An insect mouthpart comparable to an upper lip.

What is the labium?

An insect mouthpart comparable to a lower lip.

What are mandibles?

Primary jaws, used especially for chewing.

What are maxillae?

Secondary jaws or mouthparts used to manipulate food.

Which mouthparts do grasshoppers and beetles have?

Chewing mouthparts.

Which mouthparts do aphids have?

Piercing-sucking mouthparts.

Which mouthparts do houseflies have?

Sponging mouthparts.

Which mouthparts do butterflies have?

Siphoning mouthparts used for nectar.