The integration of the seed and chemical industries appears destined to accelerate increases in per-acre expenditures for seeds plus chemicals, delivering significantly lower returns to growers. Increasingly price reductions for herbicides will be limited to growers purchasing technology packages. Many farmers are willing to pay for the simplicity and robustness of the new weed management system, but such advantages may be short-lived as ecological problems arise. Recent experimental trials have shown that genetically engineered seeds do not increase the yield of crops. Glyphosphate-tolerant cotton showed no significant yield increase in either region where it was surveyed.
Many scientists claim that the ingestion of genetically engineered food is harmless.
At present there is a situation in many developing countries importing soybean and corn from USA, Argentina and Brazil, in which genetically engineered foods are beginning to flood the markets, and no one can predict all their health effects on consumers, most of whom are unaware that they are eating such food. Because genetically engineered food remains unlabelled, consumers cannot discriminate between GE and non-GE food, and should serious health problems arise, it will be extremely difficult to trace them to their source. Transgenic plants which produce their own insecticides closely follow the pesticide paradigm, which is itself rapidly failing due to pest resistance to insecticides. In general, the greater the selection pressure across time and space, the quicker and more profound the pests evolutionary response. An obvious reason for adopting this principle is that it reduces pest exposure to pesticides, retarding the evolution of resistance.