| Popis: |
Arthropods destroy an estimated 18–26 % of annual crop production worldwide, at a value of more than $ 470 billion. The greater proportion of losses (13–16 %) occurs in the field, before harvest, and losses have been heaviest in developing countries. With the Earth’s human population expected to reach 10 billion by the end of the current century, raising agricultural productivity through the prevention of crop losses to pests has assumed considerable urgency. The techniques employed in crop loss assessment provide a framework useful in identifying the causes and magnitude of crop losses, and a basis for the evaluation of control options. Crop losses to arthropods have been reported to be lower in traditional than in modern, industrial agriculture, and are thought to result from the more environmentally sound and sustainable practices employed in traditional agriculture. Many of the pest problems in modern agriculture have arisen through an over-reliance on synthetic chemicals for pest control. More environmentally sound pest control practices not only are more sustainable, but may provide greater economic benefits as well. The return per dollar invested in ecologically-based biological and cultural pest controls has been estimated to range from $ 30 to $ 300, significantly higher than the $ 4 estimated for control based on synthetic pesticides. Crop losses to pests must be reduced in ways that are compatible with sustainable production, which requires pest control to be approached in a holistic manner with a focus on the entire agroecosystem. Key to averting or minimizing crop losses to pests is a commitment, by government or other entities, to collect the data, on which reliable estimates of losses are based. |
