Over time plants, pests and diseases can develop resistance to the pesticides used to control them – meaning that these pesticides are no longer effective at dealing with the particular problem. One of the main strategies currently employed to deal with resistance is to use a wider range of active ingredients to avoid pests and diseases developing resistance. However, this leads to a greater number of actives being applied to food crops and subsequently released into the environment, exacerbating the cocktail effect.
While using a smaller a number of pesticides is therefore not the answer, there are strategies available that enable farmers to reduce both the risk of exposure to pesticide cocktails and the build-up of resistance. Adopting the methods and principles used by organic growers, such as varied rotations, selection of pest and disease resistant varieties and increasing the numbers of beneficial insect predators can all help reduce both the quantity and variety of pesticides applied.