Beneficios De Los Transgénicos

Journal of Animal andFeed Sciences, 11,2002, 1-18

Environmental benefits of genetically modified crops: Global and European perspectives on their ability to reduce pesticide use

R.H. Phipps and J.R. Park

Centre for Dairy Research, Department of Agriculture, The University of Reading Reading RG6 6A1,UK (Received 27 November 200 l; accepted 31 January 2002)

ABSTRACT The GreenRevolution, which brought together improved varieties, increased use off ertilizer, irrigation and synthetic pesticides, is credited with helping to feed the current global population of 6 billion. While this paper recognizes the ability of pesticide\, to reduce crop losses, it also discusses their potential negative effects on public health, with particular emphasis in developing countries, and theenvironment. The response of the agricultural industry in bringing forward new technology such as reduced application rates of targeted pesticides with lower toxicity and persistency is noted. However, with increasing world population, a slowing of the rate of crop improvement through conventional breeding and a declining area of land available for food production there is a need for new technologies toproduce more food of improved nutritional value in an environmentally acceptable and sustainable manner. Whilst the authors' recognize that the introduction of genetically modified (GM) crops is controversial, the benefits of these crops, including their effect on pesticide use is only now beginning to be documented. Published data are used to estimate what effect GM crops have had on pesticideuse first on a global basis, and then to predict what effect they would have if widely grown in the European Union (EU). On a global basis GM technology has reduced pesticide use, with the size of the reduction varying between crops and the introduced trait. It is estimated that the use of GM soyabean, oil seed rape, cotton and maize varieties modified for herbicide tolerance and insect protected GMvarieties of cotton reduced pesticide use by a total of22.3 million kg of formulated product in the year 2000. Estimates indicate that if 50% of the maize, oil seed rape, sugar beet, and cotton grown in the EU were GM varieties, pesticide used in the EU/annum would decrease by 14.5 million kg of formulated product (4.4 million kg active ingredient). In addition there would be a reduction of 7.5million ha sprayed which would save 20.5 million litres of diesel and result in a reduction of approximately 73,000 t of carbon dioxide being released into the atmosphere. The paper also points to areas where GM technology may make further marked reductions in global pesticide use. KEY WORDS: GM crops, pesticide reduction, global, European Union

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GENETICALLY MODIFIED CROPS

AN HISTORICALPERSPECTlVE The Green Revolution, fathered in the 1960's by Norman Borlaug, heralded one of the major agricultural developments of the last century. The production of new cereal varieties, coupled with increased use of fertilizers, irrigation and pesticides, provided many of the technological inputs required to feed an expanding world population. Since their introduction in 1947, syntheticpesticides have been widely used to reduce crop losses due to insects, diseases and weeds. Even so these losses for eight of the world's major crops are estimated at US$ 244 billion/annum, representing 43% of world production (Oerke et al., 1995) and post-harvest losses contribute a further 10%. Paoletti and Pimentel (2000) estimated that, if it were not for synthetic pesticide use, current crop lossesmight well increase by a further 30%. Huang et al. (2001) quote officials as saying that pesticide use saves China millions of tonnes of food and fibre every year. Thus, the combined effects of improved varieties, increased fertilizer use and irrigation coupled with increased pesticide use has been instrumental in allowing world food production to double in the last 35 years (Tillman, 1999)....