Pests of Crops Agricultural Science SS 2 Second Term Lesson Notes
AGRICULTURAL SCIENCE SS 2 SECOND TERM LESSON NOTES
WEEK 6: PESTS OF CROPS (II)
Lesson Details
- Subject: Agricultural Science
- Class: SS 2
- Term: Second Term
- Week: 6
- Age: 14 – 17 years
- Topic: Pests of Crops (II)
- Sub-topic: Types, Effects, and Control of Crop Pests
- Duration: 40 minutes
Behavioral Objectives
At the end of this lesson, students should be able to:
- Define crop pests and explain their economic importance.
- Identify different types of crop pests.
- Classify pests based on their feeding modes.
- Explain various methods of pest prevention and control.
- Complete the table of insect pests, crops attacked, and their control measures.
Keywords
- Pest
- Insects
- Nematodes
- Rodents
- Piercing and Sucking
- Biting and Chewing
- Burrowing
Set Induction
The teacher displays images or real-life examples of damaged crops due to pest attacks and asks students to identify the causes of the damage.
Entry Behavior
Students are familiar with the concept of living organisms and their interactions in the environment. They have also learned about plant growth and development in previous lessons.
Learning Resources and Materials
- Charts showing different crop pests
- Samples of affected plants or fruits
- Videos or slides on pest control methods
- Live or preserved insect specimens
Building Background/Connection to Prior Knowledge
Students have previously learned about plant diseases and how they affect crop yield. This lesson builds on that knowledge by introducing pests as another factor affecting plant health and productivity.
Embedded Core Skills
- Observation
- Critical Thinking
- Problem-Solving
- Communication
Learning Materials
- Lagos State Scheme of Work for Agricultural Science
- Agricultural Science Textbooks
Reference Books
- Lagos State Scheme of Work
- Agricultural Science for Senior Secondary Schools by O.A. Iwena
- WAEC & NECO Past Questions on Agricultural Science
Instructional Materials
- Pictures and diagrams of crop pests
- Videos on pest infestation
- Real-life samples of pest-infested crops
Lesson Content
Definition of Crop Pests
A pest is any organism (animal or plant) that causes harm to crops, livestock, or forestry. These organisms reduce crop yields, damage stored products, and lower the quality of produce.
Types of Crop Pests
Crop pests can be categorized into the following groups:
- Insects – e.g., caterpillars, grasshoppers, beetles
- Birds – e.g., weaverbirds, parrots
- Rodents – e.g., rats, mice
- Mammals (Man and Livestock) – e.g., stray cattle, goats, and humans
- Nematodes – e.g., root-knot nematodes
Classification of Crop Pests Based on Feeding Mode
- Biting and Chewing Pests – These pests use their mouthparts to chew plant parts. Examples include caterpillars, grasshoppers, and beetles.
- Piercing and Sucking Pests – These pests suck sap from plants using needle-like mouthparts. Examples include aphids, whiteflies, and mealybugs.
- Burrowing Pests – These pests burrow into plant stems, roots, or fruits. Examples include stem borers and weevils.
Prevention and Control of Crop Pests
Crop pests can be controlled using the following methods:
- Physical Control – Using traps, hand-picking insects, or installing bird nets.
- Cultural Control – Practices like crop rotation, early planting, and weeding.
- Biological Control – Using natural predators like ladybugs to control aphids.
- Chemical Control – Applying pesticides and insecticides to kill pests.
Economic Importance of Crop Pests
Crop pests cause significant economic losses to farmers in the following ways:
- Reduction in Crop Yield – Pests destroy crops, leading to lower productivity.
- Poor Quality of Produce – Infested crops may be unsuitable for sale or consumption.
- Financial Losses – Farmers spend money on pesticides, and pest damage reduces profits.
- Total Crop Failure – Severe infestations can lead to complete loss of crops.
- Reduction in Seed Viability – Stored seeds can be damaged by pests, reducing their ability to germinate.
Table of Crop Pests, Affected Crops, and Control Measures
| Insect Pest | Crops Attacked | Prevention and Control Measures |
|---|---|---|
| Leaf Beetles | Cassava, yam, potatoes | Use resistant varieties, apply insecticides |
| Grasshoppers | Rice, maize, millet | Use of biological control, insecticides |
| Stem Borers | Maize, sugarcane | Destroy infested plants, crop rotation |
| Aphids | Beans, vegetables | Introduce ladybugs, use neem extracts |
| Weevils | Stored grains (rice, maize) | Proper storage, fumigation |
Class Activity Discussion
Frequently Asked Questions (FAQs) on Crop Pests
- What is a crop pest?
- A crop pest is any organism that causes harm to crops.
- Give three examples of crop pests.
- Insects, birds, rodents.
- How do biting and chewing insects damage crops?
- They chew plant parts, reducing growth and yield.
- What is an example of a piercing and sucking insect?
- Aphids.
- Why are rodents considered pests?
- They eat stored grains and damage plant roots.
- How can cultural control methods help in pest management?
- Crop rotation and timely planting reduce pest infestation.
- What is an example of a biological pest control method?
- Using natural predators like ladybugs to eat aphids.
- Why do we use pesticides?
- To kill pests and prevent crop damage.
- Name one disadvantage of chemical control.
- It can harm beneficial insects and the environment.
- What is fumigation?
- The use of chemicals to kill storage pests.
- Why do we use resistant crop varieties?
- They are less likely to be damaged by pests.
- How does intercropping help in pest control?
- It confuses pests and reduces their spread.
- What is the best method for controlling birds on farms?
- Using scarecrows or bird nets.
- Can humans be considered crop pests? Why?
- Yes, through deforestation, overgrazing, and trampling crops.
- Which pest damages maize the most?
- Stem borers.
Presentation Steps
- The teacher revises the previous lesson.
- The teacher introduces the new topic and explains crop pests.
- The teacher allows students to identify examples of crop pests.
- The teacher demonstrates various pest control methods.
- The teacher engages students in a class discussion and activities.
Evaluation Questions
- Define a crop pest.
- List three types of crop pests.
- Explain two effects of pests on crops.
- Name three categories of insect pests based on their feeding habits.
- State two methods of pest control.
- Give one example of a pest that damages stored grains.
- What is an example of biological pest control?
- How do aphids damage plants?
- Why is it important to control pests on farms?
- Mention two economic losses caused by pests.
Conclusion
The teacher summarizes the key points and gives students a take-home assignment to research pest control strategies used in their locality.