General Prevention And Control Of Crop Pests

CONTENT

• Physical control
• Chemical control
• Biological control
• Cultural control

METHODS OF PEST CONTROL

Crop pests can be prevented or controlled through the following methods:

1. Physical control
2. Cultural control
3. Biological control
4. Chemical control

PHYSICAL CONTROL

This involves the physical removal of pests by:

1. Hand picking of insects and larvae
2. Setting traps to catch rodents
3. Shooting rodents with gun
4. Fencing round the farm with wire nets.
5. Use of scarecrow.

EVALUATION

1. List the methods of pest control
2. List three ways by which pests can be removed physically

CULTURAL CONTROL

This method involves the use of farm practices to prevent or control pests, examples of cultural control are:

1. Practicing crop rotation
2. Use of pest resistant varieties of crops
3. Appropriate tillage operations
4. Burning crop residues
5. Timely planting of crops
6. Proper weeding or sanitation
7. Timely harvesting
8. Close season practices (no living plant is allowed for a certain period).

BIOLOGICAL CONTROL

This involves the introduction of natural enemies of pests to control or keep the pests population under control. Such enemies eat up or feed on these pests, thereby reduce the population of the pests.

EVALUATION

1. List two cultural control of pests
2. Explain biological pest control

CHEMICAL CONTROL

This involves the use of chemical called pesticides to control pest of crop plants. Examples of pesticides are insecticide, rodenticide, avicide etc.

Examples of chemicals used to control pests are:

1. Insecticides – for controlling insect pest e.g grasshopper
2. Rodenticides – chemical control for rodents such as rats
3. Avicides – for controlling bird pest
4. Nematicides – chemical used to control nematodes. E.g worms

FORMS OR GROUPS OF INSECTICIDES

The four groups and the mode of action are:

Group	Mode of action
Powder	Contact
Liquid	Systemic
Granules	Stomach (Ingestion)
Gas	Fumigation

SIDE EFFECT OF THE VARIOUS PREVENTIVE AND CONTROL METHOD OF DISEASE AND PEST OF CROPS

Use of these control methods have their effect, these effects includes

1. Death of some beneficial insect and soil organism, toxic exposure to animals and man, chemical residue in the environment, washing away of chemicals into aquatic life e.t.c when chemical control method is employed.
2. Organisms introduced may attack cultivated crops or stored grains, predators might not feed on targeted pest and deviate to feeding on beneficial organisms, the activities of new organism might cause an ecosystem imbalance when biological control method is employed.
3. When cultural control method is employed, the use of bush burning method might get out of hand thereby destroying soil structure, spread to other farms, loss of organic matter and lead to death of beneficial microbes.

GENERAL EVALUATION

1. What are insecticides?
2. List the three forms of insecticides and their mode of action
3. What are avicides, rodenticide and nematicides are used to control
4. List five economic importance of crop pests.

READING ASSIGNMENT

Revision question 10, 14 and 16 Essential agricultural science for senior secondary schools chapter 26, pages 247-248.

WEEKEND ASSIGNMENT

SECTION A

1. Avicides are used to control _____. A. rodents B. birds C. insects D. pests
2. The mode of action of liquid insecticide is_____. A. contact B. systemic C. stomach D. fumigation
3. Weevils are _____ insects. A. biting B. chewing C. burrowing D. piercing
4. The following are pests except. A. rodents B. earthworm C. monkeys D. nematodes
5. The following are biting chewing insects except _____. A. butterfly B. locust C. grasshopper D. cricket

SECTION B

List two side effects each of using

1. Cultural control of pests
2. Biological control of pests
3. Chemical control of pests
4. Physical control of pests