Table Of Contents
- Description Of Pests Of Crops
- Types Of Crop Pest
- Classification Of Insect Pests
- Effects Or Economic Importance Of Insect Pests In Crop Production
- Prevention And Control Of Pests
- Diseases Of Crop
- Causes Of Crop Diseases
- General Effects Of Diseases On Crop Production
- General Control Of Plant Diseases
- Summary Of General Control Measures Of Diseases Of Crops
Important Pests And Diseases In Agriculture
Pests Of Crops: A pest can be described as any organism capable of causing damage to the crop plant.
Types Of Crop Pest
Important pests of crop plants are grouped into the following classing:
Classification Of Insect Pests
These can be classified into various groups based on their mode of feeding. These groups of insect pests include:
1. Biting and chewing insects,
2. Piercing and sucking insects,
3. Boring insects.
1. Biting and chewing insects: These insect pests possess strong mandible and maxillae (mouth parts), which enable them to bite and chew plant parts. Examples include termites, grasshoppers, leaf worms, armyworms, mantids, locusts, beetles, etc.
2. Piercing and sucking insects: These insect pests possess strong mouth-parts called proboscis, which enable them to pierce through plants and suck liquid materials from plants’ tissues. Examples include Aphids, cotton stainers, mealybugs, scale insects, capsids or mirids, white flies, etc.
3. Boring insects: These insects, including their larvae, can be boring into plant parts and destroy the tissues of the plant, fruits, or seeds. Examples include bean beetles, stem borers, maize weevils, and rice weevils.
Effects or Economic Importance Of Insect Pests In Crop Production
1. Insect pests destroy crops in the field by biting, chewing, boring, sucking, and defoliation activities.
2. They cause a reduction in the viability of stored produce.
3. Site of injuries by insects may predispose crops to disease attack.
4. They increase the cost of production by controlling them.
5. They render vegetables and fruits unattractive and unremarkable.
6. Some are carriers or vectors of diseases.
7. The profits of farmers are reduced.
Prevention And Control Of Pests
Pests of crops can be prevented or controlled through the following methods:
1. Physical control
2. Cultural control
3. Biological control
4. Chemical control
1. Physical control: This involves the physical removal of pests by:
i. Hand-picking of insects and larvae,
ii. Setting traps to catch rodents,
iii. Shooting rodents with a gun,
iv. Fencing around the farm with wire nets.
2. Cultural control: This method involves using farm practices to prevent or control pests, especially on the field. Examples of cultural control include:
i. Bush following
ii. Crop rotation
iii. Change in the time of planting
iv. Regular weeding
v. Bush burning
3. Biological control: Biological control involves the introduction of the natural enemies of pests to control or keep the pest’s population under control.
4. Chemical control: Chemical control involves using chemicals called pesticides to control pests of crop plants. Examples are:
i. Pesticides: chemicals to control pests.
ii. Insecticides: chemicals to control insects.
iii. Rodenticides: chemicals to control rodents.
iv. Avicides: chemicals to control birds.
v. Nematicides: chemicals to control nematodes.
Diseases Of Crop
Causes Of Crop Diseases
The following agents cause diseases in crops:
v. Nutrient deficiency
General Effects Of Diseases On Crop Production
Diseases of crop plants can be controlled through cultural, biological, and chemical control.
1. Chemical Control: Cultural control involves crop rotation, resistant varieties, tillage practices, regular weeding, fallowing, timely planting, pruning, uprooting, burning infected crops, etc., to control or prevent diseases.
2. Biological Control: Biological control involves using natural enemies of the disease to reduce or eliminate the disease.
3. Chemical control: Chemical control involves using chemicals such as fungicides, nematicides, and insecticides to dust or spray plants and plant materials to prevent or control plant diseases.