Miracle or menace? : biotechnology and the third world / by Robert Walgate.

  • Walgate, Robert
Date:
[1990]
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: Miracle or menace? : biotechnology and the third world / by Robert Walgate. Source: Wellcome Collection.

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    Chapter 4: Plant genetic engineering single-gene genetic engineering, are at present the only way of making this sort of transfer, and they inevitably bring many other genes along as well. However, the control and transfer of the numerous genes involved in nitrogen fixation (the conversion of inert atmospheric nitrogen into ammonia, a form which plants can use) from the bacterium-legume association to other plants such as cereals, will take longer than 15 years, a panel of US biotechnologists has predicted [З]. Some researchers even believe that the introduction of the nitrogen-fixing genes from bacteria into a plant could reduce its yield by 20-30%, because nitrogen fixation requires a great deal of energy, which would have to be tapped from the plant's own photosynthetic resources [4]. In the first instance, the commercial exploitation of genetically engineered plants will aim, with the simplest single-gene technologies, at the largest market. This is judged to be that of reducing the costs of Northern farmers in fighting weeds, insects and crop diseases. New tests for diagnosing and detecting disease will also be among the first dividends of this research. Genetic engineers working on developing country crops are likely to have to rely on spin-off from this research. WEED CONTROL: GENES FOR HERBICIDE RESISTANCE Weed control is the current commercial terminology for using genetic engineering to make crop plants resistant to herbicides, allowing farmers to spray growing crops to kill weeds but not their crops. An alternative to engineering in herbicide tolerance would be to engineer plants to contain natural weedkillers — for many plants have mechanisms for defending themselves from encroaching neighbours. But little is known about the genetic mechanisms involved. Meanwhile, Monsanto, which among other agrochemical companies has developed herbicide-tolerance genes [5], claims that its commercial strategy is to gain market share for its herbicides, and not to increase the overall use of herbicides, as popularly held. Sensitive to the fears and criticisms of the environmental movement, Monsanto scientists claim that their research has concentrated on herbicides which need to be applied only in small amounts, have low toxicity, degrade quickly, and stick in the soil rather than washing easily into streams or groundwater. However, herbicide use may well increase, because farmers will be able to spray them more liberally and often, without fear of
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