Why are herbicide tolerant crops being developed and how will herbicide use be affected?
Genetically modified herbicide tolerant (GMHT) crops are the only type of GMO likely to receive market approval and to be marketed in the UK in the next 3 years. These crops are genetically modified to be resistant to herbicides. Application of herbicides is often necessary at important stages of crop growth to reduce competition by weed species and volunteer plants from previous crops. As herbicide tolerant crops are designed to be used with the herbicides in question, it is intended that these products will be used instead of other herbicides. Consequently, the pattern of herbicide usage may change, but the overall application, in terms of tonnage and area on which it is used, may not increase. Research by the US Department of Agriculture (USDA) has reported treatment patterns for crops grown in 1997. Three crops were examined in up to five different regions. In four out of eight crop/region combinations, statistically significant reductions in ‘acre-treatments’ were observed. No sta
