Brifely: Non-Pesticide Managament is the way to escape the pesticide trap
Non-Pesticide Management (NPM) provides a set of natural alternatives to chemical pesticides. The core of the NPM strategy is use of the neem tree. Neem seeds are ground into a powder that is soaked overnight in water and sprayed onto the crop. To be effective, it is necessary to spray at least every ten days. Neem does not directly kill insects on the crop. It acts as a repellent, protecting the crop from damage. The insects starve and die within a few days. Neem also suppresses the hatching of pest insects from their eggs. Neem is not only much less expensive than chemical insecticides, it also has the advantage of not killing predatory insects that provide natural control of pest insects. Neem leaves can be used to protect stored grain from damage due to insect such as weevils, and neem cake can be applied to the soil. Neem cake kills pest insects in the soil while serving as an organic fertilizer high in nitrogen.
Cotton farmers in Andhra Pradesh’s Khamman District had descended into a seemingly hopeless abyss of escalating pesticide dependence and debt. Suicides were becoming common. Non-Pesticide Management was the tipping point that brought health and hope to the farmers in Punukula village. Hundreds of villages are now embarking on the same path.
The use of neem is complemented by other methods in the NPM toolkit:
- Spraying chili-garlic solution on the cotton. The solution is prepared by soaking chili and garlic powder in water for 24 hours. Chili-garlic solution kills pest insects directly when sprayed on a crop.
- Applying a mixture cow dung and urine to combat leaf hoppers and aphids. Cow dung/urine acts as a repellent and disrupts insect growth.
- Manual removal of leaves that are heavily infested with pest insects.
- Planting “trap crops” (e.g., sorghum, marigold, castor, and green gum) around the edge of the field to attract pest insects away from the crop. The trap crops are checked daily. Parts of the plants with insect eggs are removed and burned.
- Putting yellow and white wooden disks in the fields. The yellow disks, which attract sucking insects (e.g., mites and thrips), and white disks which attracts white flies, are covered with sticky grease to trap the insects. Lighting small bonfires on moonless nights to attract and kill moths before they can lay eggs in the field.
- Placing perches for insectivorous birds in the fields.
- Deep summer plowing to destroy the pupae of cotton bollworms, army worms and other pests whose pupae are in the soil.
- Applying a “Nuclear poly Hydral” virus extract. Pest larvae attacked by this virus are easily recognized because they are hanging upside down from leaf edges if the crop. Farmers collect 250 infected larvae, grind them into a solution, and spray the solution on the crop. The solution from 250 larvae (“250 LE”) is sufficient to kill the larvae on one acre of cotton crop.
- Using inexpensive pheromone tablets to attract pest insects in order to monitor their abundance. Neem, chili-garlic, or cow dung/urine are sprayed on crops only when and where they are really needed.
Once NPM was in place, the farmers of Punukula started to make vermi-compost (earthworm compost) with a mixture of cow and buffalo manure, dried leaves, and rice straw, applying the compost to their fields instead of chemical fertilizer. The compost has eliminated cash outlays for chemical fertilizers and provided other benefits as well. We were told that food grown with vermi-compost, when cooked and stored without refrigeration, will last for a longer time without spoiling than food grown with chemical fertilizers. We also were told that crops grown with compost are less attractive to insect pests than crops grown with chemical fertilizers. Composting is not without difficulties. The supply of cow manure is limited. Most families have fewer cows than in the past.
NPM has brought noticeable changes to the village environment. Insecticide containers no longer litter the village, and the village no longer smells of insecticides. Birds have returned, and so have insects that prey on cotton pests. The natural control that birds and predatory insects provide has allowed the farmers to reduce the intensity of their NPM activities. Some farmers do not need to spray neem or chili-garlic at all. The farmers have become “citizen scientists” who can monitor pest insect populations in their fields and adjust their use of NPM methods to changing conditions.
Health problems due to insecticides have disappeared. Before NPM, there were dozens of cases of acute pesticide poisoning every year. Now there are none. There have been substantial improvements in farmer income. Farmers are substituting labor inputs for cash inputs when they use NPM and composting.