About Lesson
Mechanical Methods of Pest Control
Definition:
The reduction or suppression of insect populations by means of manual devices or machines is referred to as mechanical control. It involves the use of mechanical devices and manual efforts to destroy or exclude pests.
Methods of Mechanical Control:
- Collection and Destruction Insects at different life stages are killed manually or using mechanical devices.
a.) Manual Methods:
- Handpicking of insect stages
- Egg masses of rice stem borer, Spodoptera, red hairy caterpillar can be collected and destroyed.
- Caterpillars (1st and 2nd instars) of Spodoptera, Bihar hairy caterpillar, red hairy caterpillar can be manually removed.
- Destruction of infested plant parts
- Infested cane stalks harboring larvae of Gurdaspur borer and Plassy borer can be destroyed.
- Fallen infested fruits can be removed to control fruit flies and fruit borers.
- Rosette flowers and withered terminals attacked by pink bollworm should be removed.
- Pruning of infested shoots and flowers prevents the multiplication of scales, mealy bugs, aphids, etc.
- Other Manual Methods
- Passing a rope across rice fields dislodges caseworms into standing water, which is then drained out.
- Iron hook is used to remove adult Rhinoceros beetles.
- Sieving and winnowing remove red flour beetle (sieving) and rice weevil (winnowing).
- Clipping and destroying aphid-infested twigs help in managing mustard aphids.
b. Mechanical Devices:
- Entoletor: Uses centrifugal force to break infested kernels and kill stored product pests.
- Tillage Implements: Used to expose soil-borne insects like red hairy caterpillar.
- Mechanical Traps:
- Rat traps
- Screw crow
- Use of sting slot
- Drumming
- Insect collection nets
- Preventive Barriers (Mechanical Exclusion)
Mechanical barriers prevent insect pests from accessing their hosts.
- Wrapping Fruits: Covering with polythene bags protects pomegranate fruits from borers.
- Banding: Applying grease or polythene sheet around the trunk of mango trees prevents mealy bugs from climbing and laying eggs.
- Netting: Used in mosquito control and vector control in greenhouses.
- Trenching: Digging 30-60 cm wide and 50 cm deep trenches traps marching larvae of red hairy caterpillars, locusts, and armyworms.
- Tin Barriers: Tin bands fixed on coconut palms prevent damage by rats.
- Electric Fencing: Normal or low-voltage charged fences keep away animal pests like rats, jackals, monkeys, etc.
- Trapping Methods
Traps are used to attract, monitor, and kill insect pests.
- Light Trap: Used to attract nocturnal, phototactic insects for monitoring and control.
- Sticky Trap:
- Yellow color traps attract cotton whitefly, aphids, and thrips.
- Sticky material (castor oil or grease) is smeared on surfaces to trap insects.
- Bait Trap: Uses attractants and insecticides to lure and kill insects.
- Fish Meal Trap: Used to control sorghum shoot fly.
- Pitfall Trap: Captures soil-surface insects like ground beetles and collembolans.
- Pheromone Trap: Contains synthetic sex pheromones to attract and trap male insects.
- Probe Trap: Inserted into stored grain to trap rice weevils, Rhizopertha, and Tribolium.
Advantages of Mechanical Control:
- Utilizes home labor
- Requires low-cost equipment.
- No need for high technical skills.
- No chemical residue problems.
Disadvantages of Mechanical Control:
- Requires repeated application, making it labor-intensive.
- Limited to small-scale applications (e.g., kitchen gardens).
