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Genetic engineers create crops.

Genetic engineering is creating plants which have never occurred in nature. But it is too expensive for most Third World countries to carry out research, and for this reason research up to now has focused on commercial crops in the

developed countries.

But now, the UN Food & Agriculture Organisation (FAO) has pointed out the need to bring the benefits of genetic engineering to Third World countries and to the crops that are important to them.

Genetic engineering creates plants which kill the insects that try to eat them. Others disable viruses as they attack, manufacture their own fertiliser or grow on marginal lands. Some of these plants are already being tested, and some will be sold to farmers soon.


Although the potential is great, there are also dangers. Engineered crops may pass their properties on to wild relatives, making "superweeds". A research priority is to create herbicide-resistant plants, so that more weedkiller can be sprayed on crops; this will increase the use of highly toxic herbicides.

Genetic engineering is largely controlled by a handful of multinational corporations based in the industrialised countries.

The FAO has proclaimed that "biotechnology research does not focus on the needs or interests of developing countries".


Ownership of new genetically engineered plants is becoming a key issue, because of patenting requirements to be included in the new version of the General Agreement on Tariffs & Trade (Gatt). In some cases, farmers may no longer be able to save seed from one crop and use it the following year.

The FAO has also warned that "researchers are working to develop new products and processes that could replace some of the developing countries' most valuable exports, such as tropical oils, vanilla, pyrethrum and rubber."

There is also an issue of safety. Southern countries lack the rules and the scientists to control field tests of new genetically engineered crops adequately.

Genetic engineering, also known as genetic modification or bioengineering, is the manipulation of deoxyribonucleic acid, or DNA. Genes are made of DNA, which carries all the information living things inherit from their parents. DNA contains all the instructions needed to make the proteins and other materials which make up an organism, as well as information on its structure and the way in which it functions.

In genetic engineering, genes are selected and moved from one organism to another. For example, the bacterium Bacillus thuringiensis uses a gene to make a poison with which it kills insects. This gene has been incorporated into the DNA of cotton plants to make them poisonous to insects.

The broader term biotechnology includes a wide range of other techniques. These include tissue culture (the creation of identical genetic copies or "clones" of an individual plant) and cell culture (growth of plant cells in the laboratory which are then separated off and encouraged to grow as real plants).

Brewing, bread and cheese

In its wider sense, biotechnology also includes biological processes used in the food industry. Some of these have been used for centuries, like yeasts to help make bread rise and help convert sugar to alcohol in brewing, and bacteria to digest sugars and add flavour in the making of cheese and yoghurt.

But these techniques all use naturally occurring organisms. Genetic engineering creates viruses, bacteria, yeasts, plants and animals which have never occurred in nature.

Leading the invasion into the marketplace in the US is something called the Flavr Savr tomato. This is expected to be on sale in US supermarkets soon and will be the first genetically modified food known to have been sold to consumers. A gene has been introduced into it which confuses the tomato's natural tendency to soften when ripe, so that it will remain hard enough to handle during transport and in supermarkets.

The US company Escagenetics is working on genetically altered coffee, to change flavour, to reduce caffeine content (there is a body of opinion which argues that caffeine is unhealthy in large quantities, though not all experts agree about this) or to increase the proportion of solids which can be extracted to make soluble, "instant" coffee. Another US firm, Sungene, is working to develop sunflowers whose oil is high in oleic acid, which some contend may protect against heart disease.

Awaiting approval

Many genetically modified crops are currently awaiting official approval. Those already field-tested in the US which are now waiting for commercial permits include these:

* alfalfa, maize, cotton, tobacco, potato and soya beans that have been modified to tolerate herbicide;

* apple, oilseed rape, maize, cotton, potato, rice, strawberry, tobacco, tomato and walnut modified to resist insects;

* alfalfa, melon, maize, cucumber, papaya, potato, rice, squash, tobacco and tomato modified to resist virus infections; and

* oilseed rape, maize, tomatoes, rice, potatoes, soya beans and sunflowers modified to alter the nutritional properties or increase yield.

According to David King of the London-based Genetics Forum, there have already been 1,000 releases into the field of genetically modified plants and bacteria around the world, most in the North - particularly in the US, Canada, the UK, Belgium and France. In the South, genetically engineered crops are being tested in Brazil, China, Mexico and elsewhere.

Most crops grow well enough in a fertile field with a reliable water supply. But most farmers do not have fields like that. For many, rainfall is irregular. Faulty irrigation schemes have ruined land with salt. An estimated 40% of all the world's cultivated soils are affected to some degree by aluminium toxicity, including most acid upland soils in tropical areas.

Researchers hope eventually to use genetic engineering to borrow the ability of some plants to endure the toughest conditions, transferring it to food crops. The Rockefeller Foundation is interested in developing rice which is more tolerant of cold, and attempts are also expected to develop a frost-tolerant coffee.

Resistance to insects

Insects cause some of the most dramatic crop losses, particularly in monoculture fields. Some plants and bacteria produce substances which are repellent or toxic to insects but which are relatively harmless to other creatures. Engineering the gene for these substances into crops could dramatically cut losses to insect pests and could reduce the use of toxic insecticides. Although the engineered crop is designed to be harmless to itself and its other consumers, an insect that starts to eat it will die.

The laboratory of the International Centre for Genetic Engineering & Biotechnology (ICGEB) in New Delhi has transferred to rice the gene in soya beans which inhibits trypsin, an essential enzyme for many insect pests. The plants are still under test, but it is anticipated that digestion will cease in stem borers which eat the engineered rice, so they will starve to death.

Viral and fungal diseases damage many crops. Although virus infections cannot be treated directly, many are spread by insects such as aphids. Farmers often spray with insecticide to reduce the spread of virus diseases and use fungicides against fungus diseases such as wilt, rust and mildew.

Crops have been genetically engineered to resist viral infection by giving the plant the gene which manufactures the same protein that coats the virus. This makes it harder for the virus to infect the plant. Tomatoes, tobacco and potatoes are among the first crops to be engineered in this way.


Genetic engineering could alter the nutritional content of crops. Although this goal is further away than pest and disease resistance, a few projects have begun, including these:

* The Rockefeller Foundation's rice biotechnology programme is trying to increase the vitamin A content of rice at the New Delhi laboratory of ICGEB;

* Research at Jawaharlal University in New Delhi has isolated the protein gene from Amaranthus (ramdana) which is better-balanced for human nutrition than the proteins in maize, wheat and many peas and beans; this gene could now be incorporated into other, more commonly grown food crops to improve their nutritional quality.

Much of the world's population depends on rice, and recent studies show that yields from Green Revolution rice varieties are declining by between 1% and 3% per year, according to Obaidullah Khan, Assistant Director-General of the FAO. This is "a recipe for disaster within one generation", warns the FAO's Officer for Integrated Pest Control, Peter Kenmore.

Funding for rice

The Rockefeller Foundation's $40m rice biotechnology programme devotes half its money to genetic engineering - the largest source of such funds for rice. Research is supported in both the North and the South, with India and China the main Southern recipients of grants.

Rockefeller priorities for rice genetic engineering research are resistance to tungro virus, yellow stem-borer, gall midge and brown plant-hopper; improved breeding properties; drought, submergence and waterlogging tolerance; lodging resistance; seedling vigour; and resistance to ragged stunt virus and leaf-folder.

The first products are likely to be rices resistant to diseases and pests, and some strains may be ready for planting in two years. Research into stress resistance, like high salt or aluminium levels, is at an early stage, partly because genetic control of such properties is so complicated. Researchers at the American College in Madurai, India, are studying bacteria which thrive in aluminium-contaminated water to try to identify a gene or genes which might give the same tolerance to rice.

Drought-tolerance studies at the Bangladesh Rice Research Institute found that dryland rice protects itself with a thin layer of wax to prevent dehydration. But the thickness of the wax in rice is controlled by a whole group of genes. So they are looking for a gene from another plant which creates waxy leaves.

Research under the programme in the UK, Australia, China and Mexico is studying nitrogen-fixing by introducing genes from leguminous plants to rice.

Is this all a bit far removed from Africa? Not at all. Cassava is important to millions of subsistence farmers in Africa and elsewhere but is not an important cash crop.

It has therefore received little attention from commercial biotechnology research, or even from big donor organisations like the Rockefeller Foundation. The development of a cassava that is resistant to mosaic virus was considered the most promising objective of domestic research when the University of Zimbabwe was planning a biotechnology institute. R. Bertram, an official of the US government's Agency for International Development (USAID), told the World Bank in 1988, "There are few crops where science could have as revolutionary an impact as with cassava."

Cassava clones

Professor Graham Henshaw of Bath University in the UK contends that "if we could reproduce genetically altered mosaic virus-resistant cassava clones, it would be a tremendous benefit to African cassava farmers."

Some genetic research into cassava is taking place, mostly in Northern international research centres. This is now being co-ordinated by the Cassava Biotechnology Network (CBN), which was founded in 1989 as the Advanced Research Network on Cassava. But it took three years to secure funding (which eventually came from the Dutch government), and CBN held its inaugural meeting in Colombia only in August 1992. Unlike the Rockefeller Foundation's rice programme, the CBN does not have resources to fund research directly.

CBN's goals include improving virus and insect resistance, improving starch and protein content, decreasing cyanide content and improving storage properties. Because of the slow start, engineered cassava will not be available for several years, lagging a few years behind rice and even further behind Northern commercial crops, according to Henshaw.

Nigerian research

In the meantime, some goals have been achieved through more conventional means. Nigeria's International Institute for Tropical Agriculture (IITA) developed a biological control for mealybug, one of cassava's main pests, using a naturally occurring wasp.

Bananas and plantains, like cassava, remain poor relations in genetic crop research. Banana biotechnology has focused almost entirely on non-genetic engineering techniques with a considerable amount of research still remaining to be done before it is possible to transform bananas and plantains.

This article is extracted from Briefing Paper Number 7, released in December 1993 by the Panos Institute of London.
COPYRIGHT 1994 IC Publications Ltd.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1994 Gale, Cengage Learning. All rights reserved.

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Publication:African Business
Date:Jan 1, 1994
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