Crop protection chemistry has come a long way since then. Modern products are designed to be highly selective in their action to minimise the impact on non-target organisms. Selective activity enables, for example, the control of fungi growing on plants without damaging the plants themselves; or the control of a range of weed species without damaging the crop plants among which the weeds are growing. An essential aspect of the selectivity of a crop protection chemical is that it does not affect the consumer or the environment. Each of these effects may stem from specificity at the enzyme or receptor level, or from selective metabolism.
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