WHEN natural ecosystems are left undisturbed, they generally exist in a healthy balance.
For example, the numbers of pest and predator insect species balance one another, so plants can grow without facing a high pest challenge. Some traditional agricultural systems maintain that balance, through planting of diverse crops and indigenous crop management practices that give little opportunity for pest numbers to build up. But efforts to increase food production to support a growing population have promoted different farming methods that have brought with them increased losses to pests and diseases. As a result, use of chemical pesticides to minimize those losses has become widespread.
In the 1980s, it became apparent that overuse of chemical pesticides was having some damaging side effects. For example, pest species developed resistance to the chemicals, demanding stronger or more frequent applications. People applying the pesticides were also experiencing health problems, for example from inhalation of pesticide fumes or contamination on their skins. There were also instances of consumers being poisoned, when pesticide guidelines were not correctly followed. Beyond this, chemical pesticides were also causing damage to ecosystems, killing plants, animals, insects and fish and polluting groundwater.
Given these problems, which were particularly acute for poorer farmers who lacked specialist knowledge or proper equipment, it was clear that a different approach to farming and pest control was needed. In the late 1990s, this developed into a comprehensive methodology called Integrated Pest Management(IPM). This encouraged a broad range of methods to counter pest problems: biological control (for example using biological pesticides or pest predators); use of pest-resistant crop varieties; cultural control (such as weeding, tilling, crop spacing); and selective use of chemicals.
The IPM methodology has been developed and spread through Farmer Field Schools. This new method of agricultural extension has emphasized giving farmers the skills to learn for themselves. Farmers are taught how to make an analysis of their agro-ecosystems and to observe pest-predator relationships. As a group they experiment with solutions to problems, based on their better understanding of the ecological processes taking place in their fields.
Integrated Pest Management is not a fixed set of rules that farmers can apply to pest problems. Solutions will vary according to each situation, and finding the right solution depends on a farmer’s skill in recognizing the problem, understanding its causes and devising an appropriate remedy. Developing the skills and knowledge to use IPM effectively depends on training and therefore farmers are encouraged to participate fully in the Ministry of Agriculture’s Training Programme countrywide.