Crop yield is drastically affected by the infestation of pests.
And for this, many farmers rely on chemical and synthetic pest control methods which are harmful to human health and the environment.
To prevent this untoward damage and enhance the crop yield, natural control methods can be adopted.
Pesticides are substances sprayed over the plants to kill pests.
These pesticides can be both chemical (synthetic) and natural origin.
But, chemical pesticides are made of chemicals and are harmful in numerous ways.
They affect even the beneficial insects and kill natural pollinators like the honey bees.
Further, they cause pollution, make the pollen sterile, and show residual effects.
These chemical residues enter the food chain and cause several disorders in humans like cancer, neurological disorders, Parkinson’s disease, asthma, headaches, vomiting, depression, and suppress the immune system.
- Interestingly, with the continuous use of chemicals, the pests become resistant to these chemicals and multiply rapidly.
For example- in the mid-20th century, DDT, which was used to kill mosquitoes, did not affect these pests, but the excessive use of DDT has led to their entry into the food chain.
It has affected the birds on a large scale and entered the food chain of humans. Later due to its dangerous effects, the chemical was banned.
In modern agriculture, to increase the yield, farmers rely on chemical pesticides profusely.
These pesticides disturb the ecosystem and are carcinogenic.
To stay away from the effects of chemicals on human health, many prefer organic food, that is grown naturally without any chemicals.
Natural Pest Control Methods in Agriculture
- There are several methods to control the pests naturally by using cultural and mechanical methods.
- Also, natural pesticides can aid in the control of these pests.
- The pesticides which are derived solely from natural products without using chemicals are called natural pesticides.
- No single method of pest control has ever been proven successful in eradicating pests. Using chemicals has shown adverse effects on humans and the environment.
- So natural methods must be adopted to eradicate the pests.
- These are ideal methods of controlling pests and are safe and less damaging.
- They are farmer-friendly practices and cost-effective.
- From the selection of a site to handle them until harvest, there are several methods to control the pests naturally.
Some of the methods are
- Land Preparation
- Selection of the crop
- Monitoring the physical conditions like temperature, time of sowing
- Use of certified seeds
- Using resistant verities
- Watering the plants
- Crop rotation
- Using trap crops
- Handpicking and destroying the pests
- Pruning the plant
- Using mechanical methods to control pests like traps, nets, or any barriers
- Using biological pest control methods
- Use of natural or homemade pesticides
Deep summer plowing of the land before sowing is essential to provide aeration to the soil, activate friendly microbes inhabiting the ground, destroying weeds and hidden pests.
Plowing is helpful to remove eggs, pupa, and small insects residing in the soil.
Proper selection of crops
The crop should be selected wisely according to the climatic conditions of the area and the physical conditions of the field.
This would help to prevent the attack of the pests.
Ex; citrus plants are much more prone to pests in waterlogged conditions and sandy soil.
Temperature inhibits the activity of pests by making them inactive.
The high temperature through steam sterilization of greenhouse, hot water treatment of bulbs, and hot air treatment of godowns can be used to eradicate the pests.
Time of sowing
The time of planting should be altered for controlling pests.
Ex- Early sowing of mustard helps to avoid aphid attack
Use of certified seeds
Most farmers use seeds based on previous crops. But they may be infested and attract pests in later stages.
Certified seeds ensure clean and quality seeds. They must be used as planting material to avoid any damage.
Using resistant varieties will help to reduce the attack of pests.
Examples of Resistant Varieties in major crops
Water is the greatest source to eliminate pests.
Flooding water in the fields submerges the pests inhabiting the soil, and they flow away with water.
Ex- Soil inhabiting pests like white grubs and cutworms can be eliminated through flooding.
Washing the vegetable and fruit crops with water gets rid of pests.
Based on the plant’s strength, the leaves and stem can be cleaned with water by attaching a nozzle to the water pipe.
Ex- Aphids, mealybugs, and whiteflies can be eliminated through this method.
Shampoo and water solution can also be used against mealybugs and ants in gardens (Take2-3 ml of any shampoo in 1litre of water and mix the solution well.
Spray it over the leaves and other plant parts either early in the early morning or evening. Wash the leaves and stem later.
Crop rotation is the best practice for avoiding pests.
With the continuous sowing of similar crops in the field, the pests get food, and they get attracted, multiply rapidly, and infest the crop largely.
Thus different crops should be sown in the field during each successive sowing period.
Post harvesting the plants of the Solanaceous family (Potato, brinjal, tomato), other family crops like Malvaceae or Brassicaceae family should be grown.
You can go to crop rotation according to the nutrition they provide.
Legumes like beans, peas, groundnut, alfalfa, etc., are excellent in fixing Nitrogen in the soil.
So these should be planted first, and they should be rotated with leafy vegetables after their harvest.
Leafy vegetables help to utilize excess Nitrogen present in the soil ( help in vegetative growth).
Replace the leafy vegetables with cereals, vegetables, or fruit crops like maize, watermelon, tomato, pepper, cucumber, millets, etc. This is the ideal method of crop rotation.
This is an excellent strategy adopted to divert the pests from infestation to our primary crop.
A trap crop is grown around a significant crop in a narrow strip, attracting pests and damaging our crops.
When the pests infest the trap crop, these are cut and destroyed. Examples of trap crops are-
|Main Crop||Pest Trap crop|
|Cotton||Ladies finger, Seasame, Marigold|
|Tomato||Marigold, sunflower, cucumber|
|Cauliflower or Cabbage||Mustard, sesame|
Hand-picking and destroying
Different stages of pests like eggs, larvae, and pupa can be quickly figured out, and they should be picked up regularly and destroyed.
Ex- Aphids, cutworms, mealybugs, eggs of the lemon butterfly, grubs of mustard sawfly, all stages of Epilachna beetle; these can be easily picked out.
Pruning and destruction of crop residues
Unhealthy plants and infested parts should be cut and destroyed to prevent the spread of infestation to the remaining plants.
The residues of diseases crop must be burnt. Ex-pruning of citrus plants in April and May reduces the infestation of shoot borers.
Using Mechanical Traps
- Nets-Using nets to cover the crop will help from pest infestation. Ex- nursery of tomato and chili are covered with nets to protect from the transmission of viruses from the whitefly. The wrapping of pomegranate with a cloth or butter paper helps protect it from Anar butterfly.
- Thorns or sticks- They must be used to avoid the attack of animals. Ex-thorny plants are planted around coconut trees to save them from monkeys.
- Light traps and sticky traps- are used to catch the insects.
- Sticky traps-Aphids, whiteflies, and a few moths get attracted to yellow sticky traps.
- Light trap- Light traps are mostly used to attract adult moths. Any lamp or electric bulb is used as a trap. A soap water bowl or a plate greased with oil should be used to trap the insects.
- Making sounds-By making intense sounds and shaking the trees, some of the pests like monkeys, and wild elephants can be controlled.
Biological control methods
This method is gaining extensive popularity.
The pests are controlled on a large scale by conserving natural enemies and releasing natural predators or microbes.
These predators are friendly and feed on the crop pests and reduce their population.
Ex-1. Pupae of Epipyropsis, after becoming adults act against sugarcane Pyrilla on the young sugarcane crop.
These Pupae should not be discarded after harvesting the crop.
2. Releasing Ladybird beetle controls aphids.
3. Bacillus thuringiensis is effective against many larvae like Cabbage worms, pets in sugarcane
4. Ducks are used to control striped bugs in Rice crop
Use of natural pesticides
natural pesticides like neem oil and Diatomaceous earth ( used against slugs, maggots, flies, or rodents) can be used to control pests.
Neem oil- is considered best against pests.
It acts as antifeedant and repellent. It inhabits pests by laying eggs, mating, or even flying.
It is effective against a wide range of pests like green leafhopper and brown planthopper in rice, tobacco- caterpillars, aphids, and Powdery mildew.
To reduce the attack of pests, natural pesticides are used. These pesticides can be made at home and are organic.
They can be used to kill garden pests, especially in vegetable and fruit crops.
They are effective against aphids, mealybugs, whiteflies, caterpillars, etc.
How to make organic pesticides at home?
Pesticides with soapnuts
Any mild soaps like dishwashers, soaps, detergents, etc. can be used against silky-textured insects like caterpillars, larva, etc.
- Take a few soap nuts and break them.
- Take hot water and soak these nuts in the water for 24 hours.
- Strain it and collect the solution
Pesticides with chrysanthemum
Chrysanthemum contains an alkaloid called Pyrethrin, which paralyzes the insect and repels them.
- Boil some water and add chrysanthemum to it (the dried flower is ideal)
- Leave this for 24 hours and strain it and collect the solution.
A pesticide with Spices
- Take a few green chilies, ginger, and garlic.
- Make a fine paste of them.
- Add this paste to hot water and leave it for 24 hours.
- Strain it and collect the solution
Pesticide with Tobacco
- Take tobacco and add it to hot water.
- Leave it for 24 hours. After the solution turns to dark color, strain it, and collect the solution.
A pesticide with neem
This is considered the ideal pesticide for killing pests ( I have tried this personally in my garden, and it shows miraculous results)
- Collect neem leaves and boil them
- Leave it for 24 hours. Strain it and collect the solution
Before using these pesticides, dilute them with water in a 1:10 ratio (1 part of pesticide with ten parts of water).
Fill them in a spray bottle and spray them carefully under the leaves and on the infested parts.
- Before spraying the pesticide on a plant, test the effect on a small portion (patch test)
- Spray these pesticides in the early morning or evening
- Combining 2-3 pesticides will give better results( neem+ Soapnuts ( any detergent) or spices + neem)
The widespread use of chemical pesticides has disturbed the ecosystem and human lives.
It is high time to revolutionize agriculture with natural methods of pest control over chemical pesticides.
This would be a sustainable solution and would provide long-term benefits to protect the environment.
Additionally, they will also add to human health and better crop yields.