Safeguarding production - Losses in major crops and the role of crop protection

Abstract

It is well accepted that agricultural production must be increased considerably in the foreseeable future to meet the food and feed demands of a rising human population and increasing livestock production. Crop protection plays a key role in safeguarding crop productivity against competition from weeds, animal pests, pathogens and viruses. The loss potential of these pest groups and the actual losses - i.e. losses despite the present crop protection practices - have been estimated for wheat, rice, maize, barley, potatoes, soybeans, sugar beet and cotton for the period 1996-1998 on a regional basis for 17 regions. Among crops the loss potential of pests worldwide varied from less than 50% (on barley) to more than 80% (on sugar beet and cotton). Actual losses are estimated at 26-30% for sugar beet, barley, soybean, wheat and cotton, and 35%, 39% and 40% for maize, potatoes and rice, respectively. Overall, weeds had the highest loss potential (32%) with animal pests and pathogens being less important (18% and 15%, respectively). Although viruses cause serious problems in potatoes and sugar beets in some areas, worldwide losses due to viruses averaged 6-7% on these crops and <1-3% in other crops. The efficacy of crop protection was highest in cash crops (53-68%) and lower (43-50%) in food crops. The variation coefficient of efficacy among regions was low in cash crops (12-18%) and highest in wheat (28%). As weed control can be achieved through mechanical or chemical means, worldwide efficacy in weed control (68%) was considerably higher than the control of animal pests or diseases (39% and 32%, respectively), which relies heavily on pesticides. The intensification of crop production necessary to meet the increasing demand through enhanced productivity per unit area might be impossible without a concomitant intensification of pest control. The perspectives of integrated pest management in safeguarding crop production and preventing negative effects on the environment are discussed for developing and developed countries. © 2003 Elsevier Ltd. All rights reserved.