Crop Pests

Question 1

Term

Answer 1

Definition

Question 2

Class Insecta

Answer 2

Insects are the most diverse animal class with about 1 million identified species; many are crop pests.

Question 3

Insect Orders

Answer 3

Key orders include Diptera, Orthoptera, Hemiptera, Coleoptera, Lepidoptera, and Hymenoptera.

Question 4

Diptera

Answer 4

Flies and mosquitos; pests include leaf miners, fruit flies, and midges.

Question 5

Orthoptera

Answer 5

Grasshoppers and locusts; known for sound production and crop damage.

Question 6

Hemiptera

Answer 6

True bugs like aphids and plant lice; have piercing-sucking mouthparts.

Question 7

Coleoptera

Answer 7

Beetles; largest insect order; includes many crop-feeding pests like weevils.

Question 8

Lepidoptera

Answer 8

Butterflies and moths; larvae such as armyworms and earworms are major pests.

Question 9

Hymenoptera

Answer 9

Includes sawflies, bees, ants; some are pests (e.g. sawfly larvae) but many are beneficial.

Question 10

Class Arachnida

Answer 10

Includes ticks and mites; ticks affect livestock, spider mites damage crops.

Question 11

Spider mites

Answer 11

Small mites that live on leaves; major crop pests (e.g., Tetranychus urticae).

Question 12

Insect Life Cycle

Answer 12

Includes metamorphosis stages: larva, nymph, pupae, and adult (imago).

Question 13

Holometabolous

Answer 13

Complete metamorphosis with distinct larval and adult stages; includes butterflies.

Question 14

Hemimetabolous

Answer 14

Incomplete metamorphosis with no pupal stage; includes grasshoppers.

Question 15

Ametabolous

Answer 15

No metamorphosis; nymphs and adults look the same.

Question 16

Voltinism

Answer 16

Number of reproductive cycles per year: univoltine, bivoltine, multivoltine, or delayed.

Question 17

Univoltine

Answer 17

One generation per year (e.g., codling moth, corn borer).

Question 18

Bivoltine

Answer 18

Two generations per year (e.g., silkworm, alfalfa weevil).

Question 19

Multivoltine

Answer 19

Multiple generations per year if food is available (e.g., whiteflies, aphids).

Question 20

Delayed voltinism

Answer 20

Insects reproduce only under favorable conditions after years (e.g., cicadas).

Question 21

Crop Damage

Answer 21

Insect pests cause $70–100 billion global losses annually (~15–20% of production).

Question 22

Fall armyworm

Answer 22

Major maize pest; causes $2.5–6.3 billion in annual losses.

Question 23

Desert locust

Answer 23

Major swarm pest; damages all crops across regions like East Africa and Asia.

Question 24

Western corn rootworm

Answer 24

Known as the ‘billion dollar bug’ in the US due to corn damage.

Question 25

Whiteflies

Answer 25

Small pests causing ~$1 billion in losses; spread crop diseases.

Question 26

Injury

Answer 26

Harm to plant physiology caused by pests, not always visible.

Question 27

Damage

Answer 27

Measurable crop loss in quantity, quality, or value.

Question 28

Damage Boundary

Answer 28

Lowest injury level where economic damage begins.

Question 29

Economic Injury Level

Answer 29

Point at which pest control costs equal damage costs; also called Action Threshold.

Question 30

Insecticides

Answer 30

Chemicals used for pest control; history includes pre-insecticide, DDT era, and modern IPM.

Question 31

Pest Management

Answer 31

Modern approach focusing on ecological balance and integrated methods.

Question 32

Biological Control

Answer 32

Use of natural enemies (parasites, parasitoids, predators) to manage pests.

Question 33

Bt (Bacillus thuringiensis)

Answer 33

Bacteria producing toxin used in engineered plants for pest resistance.