Lesson Notes By Weeks and Term - Junior Secondary School 1

Date: 27^th of February- 17^th of March 2023

Class: JSS 1

Term: 2^nd Term

Week: 8-10

Subject: Agricultural Science

Topic: Pests

Duration:45 minutes

Teaching Aid: A chart

Reference Book: WABP Junior secondary Agriculture for Nigerian School 1 by Anthony Youdeowei et al

Behavioural Objectives: By the end of this topic, students should be able to

1. Define pests and classify them
2. State the economic importance of pests
3. Describe prevention and control of pests

Presentation

Step 1: Teacher revises last topic

Step 2: Teacher introduces and explains new topic

Step 3: Teacher writes note on the board

Step 4: Teacher evaluates students

Step 5: Teacher marks students' notes and give assignment

Previous knowledge: Students have been taught weeds

Content

PESTS

Pest is defined as only living organism, plant or animal which can cause damage to our cultivated crop plant, farm animal and human. Examples of common pest include insect like grasshoppers and beetles, mammals such as rats and monkey and bird such as weaver bird.

CLASSIFICATION OF INSECT PESTS ACCORDING TO THEIR FEEDING HABIT

According to their mode of feeding insect pest are classified into three groups. These are:

1. Biting and chewing insect pests
2. Piercing and sucking insect pests
3. Boring insect pests

BITTING AND CHEWING INSECT PESTS

Insect pests in this group have mouth parts which are specially made for biting and chewing plat. The mouth parts of insect in this group consist of a pair of very hard biting jaws called mandibles, a second pair of jaw called maxillae, flat upper lip called the labrum and lower lip known as librum. The mandibles are sued to bite off and chew parts of the crop while maxillae are used to bite off and chew parts of the crops into the mouth. Examples of biting and sucking insects pests are crickets, grasshoppers, beetle, termites, army worm, mantils.

PIERCING AND SUCKING INSECT PESTS

The insects in this group have mouth part that are shaped like injection needles, called probaxix, hena, their mouth parts are adapted to pierce into plant parts and sucking the sap and juice of plant. Example of piercing and sucking insects include aphids, cotton stainer, mealy buds, white flies and capsids.

BORING INSECTS

These are insects that bore hole into plats tissues and seeds. Boring insects are also called burrowing insects. Examples of boring insects are beans beetles, weevils such as rice and maize weevil.

CLASSIFICATION OF INSECT BASED ON THEIR LOCATION

Based on location, insect pest are classified into two namely:

1. Field insect pests
2. Storage insect pests

1. FIELD INSECT PEST: These are insects that attack crop plant on the field that is before harvesting important field pest include:
2. Stem borers
3. Fruit and seeders: Examples are beetle fruit, flies and fruit piercing mouth.

iii.        Root feeders: Examples are yam beetles.

1. STORRAGE INSECT PESTS: This group of insect attack harvested products in store. Examples include bean beetle, weevil such as rice and maize weevils.

ECONOMIC IMPORTANCE, PREVENTION AND CONTROL OF INSECT PESTS

Pest may cause damages to crops in the following ways:

1. Insect pest destroy field crops through their activities such as biting, chewing, boring and sucking
2. They cause reduce in the viability (germinating capacity) of stored produce

• Heavy attack by insect pest may lead to total failure

1. They reduce the market of crops especially fruits and vegetables
2. Control of insect pest increase the cost of production
3. Some insect pest act as vectors of plant diseases.

• Insects’ pests reduce the yield (quantity) and quality of crops either in the field store.

PREVENTION AND CONTROL OF INSECT PESTS

Generally, insect pests can be effectively controlled through the following measure.

1. Cultural control
2. Physical control
3. Chemical control
4. Prohibition
5. Quarantine
6. Biological control

CULTURAL CONTROL

This involves the use of good cultural practices in order to reduce or destroy insect population and to help crops escape insect attack. These cultural practices include:

1. Crop rotation
2. Tillage
3. Early planting
4. Planting resistant
5. Timely harvesting
6. Burning

PHYSICAL CONTROL

This involves the physical removal of insect pest from the farm. The following insect pest on the farm though: (i)   Hand Picking (ii) Air tight storage

BIOLOGICAL CONTROL

This involves the introduction of the natural enemies of the insect pest. The pest enemies are introduced to feed on the insect pest thereby reducing the population of the pest. For instance ladybirds are introduced in an aphid infested farm to eat up the aphid.

CHEMICAL CONTROL

This is the used of chemicals to protect crops from insect attack and if the attack is established they are used to kill the insect pests at various stages of their life cycles. Chemical control is the most effective method of controlling insect pest and chemical used for insect control include:

1. Insecticide: These are chemical specifically used for controlling insect pests. They may be applied in the form of solid such as dusts or in the form of emulsion or sprays. Examples include Gammalin 20, Vector, Aldrin dust and so on.
2. Fumigants: These are insecticides which are in the form of vapour. They are usually enclosed in air tight containers. Examples include hydrogen cyanide, methy bromide and ethylene.

QUARANTINE

Quarantine is a period of isolation and observation imposed by law in imported materials include seeds, plants and animals. The materials are kept long enough to observe them for nay disease symptoms. If symptoms are detected, the materials are either destroyed or exported to the country where it was purchased at the expense of the importer.

Evaluation: describe insect pests

Assignment: Draw and label any insect pest