|Correct citation:||nn. (1994), "Editorial: Stress seldom comes alone." Biotechnology and Development Monitor, No. 18, p. 2.|
While raising agricultural production biotechnology could overcome abiotic
stresses, such as drought, salinity and soil toxicity. It could also lead
to the substitution of expensive and environment degrading fertilizers.
In this respect, farmers who are dependent on the productivity of marginal
lands, would be among the main beneficiaries of the new technology.
Today we know that it is not all that easy. Even in parts of the world where, for example, drought occurs, research on drought tolerance does not always have high priority. This would appear to be partly due to the perception of the development of the whole agricultural sector. In Latin America, the first priority is mainly defined as raising the agricultural production. A higher agricultural output will probably be realized more easily by increasing the productivity on the already cultivated land in the more favourable climate zones than by expanding the agricultural production into the droughtprone, marginal lands. As Jaffe's and Roja's article shows, it is even questionable as to whether the latter would be desirable. This is not to say, however, that therefore research on drought tolerance is of no importance. If improving the position of the small farmers living in marginal dry areas is seen as the main aim, droughttolerant plants may appear as a priority, although other solutions, such as water conservation, should also be considered.
Additionally, the social, cultural and political environment in which the research takes place is important. As is pointed out in the article by Ruivenkamp and Richards, there are various approaches conceivable to achieve droughttolerant plants. In industrialized countries, most biotechnological research on drought tolerance is devoted to the transfer of genes encoding for this characteristic to crops such as cotton, wheat, or maize. Research institutes in developing countries, however, may follow other approaches. They can opt for the improvement of the commercial attractiveness of locally important and more droughttolerant traditional food crops. They could also employ the existing diversity in farming systems to reduce drought risk at farm level.
But let us not forget the current technical restrictions of research on drought tolerance. Unlike pest resistance, the tolerance trait of a plant to drought or salinity is determined by multiple genes. Furthermore, a stress seldom comes alone. Plants should therefore become tolerant to various abiotic stresses that might occur together.
Until now, the complexity of the tolerance mechanisms has limited the of application genetic engineering in developing transgenic stresstolerant crops. As in the case of biological nitrogen fixation, most progress has been made not by genetic engineering but by conventional breeding methods. The use of genetic markers, however, has increased the efficiency of conventional breeding methods.
Taking all these restrictions together, smallfarmers, dependent on marginal lands in droughtprone areas and growing locally important food crops, do not have much to expect from research on drought tolerance in the shortterm.
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