PESTS, ENDANGERED PESTICIDES AND PROCESSING TOMATOES

Processing tomatoes are attacked by a number of important arthropods, plant diseases and nematodes which significantly reduce fruit yield and quality. Weeds compete with tomato plants, further reducing attainable yield. Worldwide, losses due to these pests are estimated to be about 34.4% of attainable tomato yield under current production practices. Without crop protection, losses would increase to 77.7% of attainable yield. Crop protection practices employed in the EEC and North America reduce yield losses from pests to about 15.4% and 22.8% of attainable yield, respectively. In some areas of the world, tomato production losses due to all categories of pests continue to exceed 50% of attainable production.
Weeds are estimated to present the greatest potential for tomato yield loss, about 32.5% of attainable yield. Employing current crop protection practices, worldwide yield losses are only about 6.5% and are as low as 2.5% in the EEC. Similar though less dramatic reductions in actual yield loss are observed for pathogens (excluding viruses) at 40% of potential losses without crop protection, and insects and nematodes at 49% of potential losses.
The level of pest control achieved largely results from cultural practices, currently registered pesticides, pest and crop monitoring and host plant resistance. Many pesticides used on tomatoes are of concern due to biological, regulatory and social issues. In the US, and California in particular, the Food Quality Protection, Clean Water, Toxic Air Contaminants, and Safe Drinking Water and Toxic Enforcement Acts represent regulations potentially affecting pesticides registered on processing tomatoes. Internationally, residue tolerance inconsistencies between nations limit pesticide choice. Social standards, which are not independent of regulatory issues, have brought about various types of certification proposals.
Effective and economical pest management in the future will require research on the pest complex attacking processing tomatoes in an IPM context. Such research must address both biological needs and societal demands.