Topic 5: Insect Pests of Crops

Question 1

DAMAGES OF INSECT PESTS TO CROPS

Answer 1

1. defoliators
2. transmit disease
3. bore holes
4. leaf folders
5. discoloration
6. stunted growth

Question 2

TYPES OF RICE STEM BORERS

Answer 2

1. stripped (Chilo suppressalis)
2. yellow (Scirpophaga incertullas)
3. pink (Sesamia inferens)
4. white (Scirpophaga innotata)

Question 3

RICE STEM BORERS

Answer 3

1. order: lepidoptera
2. damage: whitehead (reproductive stage); deadheart (tillering/vegetative stage)
3. management strategies: cultural, mechanical, chemical, biological

Question 4

GREEN LEAFHOPPERS

Answer 4

1. Nephotettix virescens; N. nigropictus
2. damage: transmits tungro; stunted plant; reduced number of reproductive tillers
3. management strategies: cultural, physical

Question 5

BROWN PLANT HOPPER

Answer 5

1. Nilaparvata lugens
2. damage: yellowing of rice plants; rice ragged and grassy stunt
3. management strategies: mechanical, chemical, biological

Question 6

ASIATIC CORN BORER

Answer 6

1. Ostrinia furnacalis
2. damage: stalk rot symptoms; stalk lodging
3. management strategies: cultural, mechanical, chemical, biological

Question 7

COCONUT RHINOCEROS BEETLE

Answer 7

1. Oryctes rhinoceros
2. damage: triangular gashes after leaves open; entry point for red palm weevil
3. management strategies: cultural, mechanical, chemical, biological

Question 8

GOLDEN APPLE SNAIL

Answer 8

1. Pomacea canaliculata
2. damage: cut base of seedling
3. management strategies: cultural, mechanical, biological, chemical

Question 9

VERTEBRATE PESTS

Answer 9

1. birds
2. damage: squeeze rice grains (milky phase); eat entire grain (mature phase)
3. management strategies: scare away, exclusion net, bird-tapes, chemical repellents

Question 10

DIFFERENT SPECIES OF RATS

Answer 10

1. norway rat (Rattus norvegicus)
2. philippine field rat (Rattus rattus mindanensis)
3. asian field rat (Rattus argentiventer)