Crop , losses to pests

Furthermore, significant amounts of food are lost to pests. Worldwide preharvest crop losses to pests (insects, diseases, and weeds) are estimated to be about 35% each year (10). These major pest losses are occurring despite the application of about 2.5 million metric tons of pesticide, at an annual cost of 18 billion (11). Even after crops are harvested, an additional 20% of the food is lost to pests (12). Overall about 48% of all potential world food supply for humans is lost to pests despite all efforts to protect it. 

Crop Losses to Pests and Changes in Agricultural Technologies... 

Future studies must focus on those specific agricultural technologies that have contributed to the increased use of pesticides during the past 40 years, and why crop losses to pests continue to Increase. Research needs not only to identify the detrimental technologies, but, more Important, develop ecologically sound practices that farmers can use as profitable substitutes (15). 

Oerke, E.C. 2006. Centenary review. Crop losses to pests. J. Agric. Sci 144 31-43. 

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