Economic Conflicts in Plant Protection: Individual Versus Social Decisions

We are becoming increasingly aware of the unintended harm caused by the use of chemical pesticides to man, crops, livestock, and the environment. The major side‐effects of pesticides are ecosystem disruption, increasing pest resistance and environmental pollution. Market structure (prices) does not include these effects and, for this reason, the individual farmer has no incentive to consider them in his pest control decisions. This leads to conflicting economic interests between the individual farmer who uses excessive pesticides to maximize profits, and society, which considers environmental quality and other external effects as part of the costs of pesticides, and thus desires lower levels of pesticides. A case study of resistance to pesticides by the Egyptian alfalfa weevil shows that the farmers' pest control decisions lead to faster development of resistance than would be deemed desirable by the society. Economic analysis of the costs of resistance serves as the basis for estimating needed investment in new pest control means, of which the most desirable ones are environmentally neutral: some form of biological control and/or host‐plant resistance.