Pest control：练习题

At which stage of the life cycle is a boring pest, such as the stalk borer (Helicoverpa armigera), most damaging to the internal tissues of a crop plant?

A farmer observes an infestation of aphids, which are piercing and sucking pests, hidden deep within a thick crop canopy. Which chemical control method would be most effective?

Identify one specific example of a piercing and sucking pest and state one visible effect it has on a crop.

Explain the difference in the method of spread between a boring pest, such as a weevil, and a viral plant disease.

A farmer chooses to use biological control instead of chemical pesticides.
Explain two advantages of this method and one reason why it may be slower to show results than chemical control.

A farmer observes that a cereal crop is being attacked by a boring pest, such as the stalk borer (Busseola fusca).
(a) Describe the life cycle of a named boring pest.
(b) Explain one reason why boring pests are particularly difficult to control using contact pesticides once they have entered the plant tissue.

Chemical controls are often used to manage outbreaks of piercing and sucking pests.
(a) Explain the importance of correct dilution and mixing when preparing insecticides for application.
(b) Describe two specific safety precautions a farmer should take after applying farm chemicals to prevent environmental pollution.