NEW APPROACH
WEEK/TERM: THIRD TERM /WEEK 6
CLASS: Grade 3
DATE: 26th June, 2020
SUBJECT: Basic Science
TOPIC: Pest and Diseases of Crops
Reference:
Brief explanation
Notes for the Pupils
Pest are living organisms which causes discomfort to other living things. Some pests are insects but others are not. Examples are rats, monkeys, squirrels. Some insect pests are: ants, weevils, grasshoppers, locusts, beetles etc. These pests can also be called farmer’s enemies.
Classification of pests
Pest are classified into three, based on the nature of their mouth and modes of feeding.
- Biting and chewing insect: They eat leaves of plant e.g. grasshoppers, termites, locust, crickets etc.
- Piercing and sucking insects: these insects feed by putting their needle like mouth part into the tissues they feed on. They pierce and suck. E.g. birds, squirrel, monkeys etc.
- Boring pest: They eat up grains reducing them into powder e.g. maize beans, weevil etc.
Farmers’ friends
Farmers’ friends do not destroy farmers crops rather they are useful to farmers examples are butterflies, bees and moths.
Common diseases of crop plants are:
- Fungi e.g. maize rust, corn smut.
- Virus e.g. cassava mosaic, yam mosaic virus.
- Bacteria e.g. Tomato and pepper bacteria wilt.
Ways of preventing diseases of crop plants.
- Grow plants under favourable conditions.
- Use disease free seeds to plant.
- Practice crop rotation.
- Spray fungicide to protect the leaves from infection.
Exercises/Assignment
- Define weed.
- What do weeds compete for in the farm?