There are more than six billion people in the world today, all of whom must be fed. In the developing world, more than 1.2 billion people, mainly women and children, are living in extreme poverty. Producing sufficient food to go around is becoming a major challenge, as land is needed not only for producing food, but also for housing and industrial purposes. At the same time, changes in climatic conditions are causing more land to become less fertile, prone to drought conditions or the soils to become salty.

Developing countries, such as Trinidad and Tobago, can make use of biotechnological methods to produce new varieties of crops that are specially adapted to particular farming conditions and environments. Crops that can tolerate drought or saline soils, are resistant to pest and diseases, and are thus more productive, can be produced through biotechnology.

There are two areas of biotechnology that are relevant to increased food production: tissue culture and gene manipulation or genetic engineering.

Tissue Culture

In 1939 it was discovered that it is possible to keep plant cells that are removed from the parent body, in a living state under carefully controlled environmental conditions. This discovery led to the practice of tissue culture that allows for the production of whole plants from single cells or clumps of cells, a process known as plant cloning.

Under conditions similar to those used to clone plants from single cells, shoots can be made to multiply rapidly, which when rooted produce many plants that are genetically identical. In this way a farmer can obtain many plants within a short time. An extension of the technique can also be used to rid a plant species of viruses.

Tissue culture has been used in the production of planting material of crops such as corn, soybean, rice, canola and tomato. In the Caribbean, the technology has been used in the production of plant species such as plantains, pineapples, bananas, sweet potatoes, cassava, breadfruit, ginger, and rice.

Genetic Engineering

Traditionally, improving a plant species has been achieved by breeding – crossing a plant with a desirable characteristic with one that lacks that characteristic, with the hope of transferring the gene for the desirable characteristic from the former to the latter. This process, however, takes time, which in the case of tree crops can be years. Additionally, the results cannot be controlled and a desirable characteristic in the target crop might be lost in the process, or an undesirable characteristic may be introduced along with the desired one. New discoveries in science have helped to overcome this constraint.

In 1953, the structure of the DNA molecule- the blue print of life- was first elucidated. A decade later, it was discovered that the molecule can be manipulated; portions can be cut from the DNA of one organism and combined with portions from other organisms. This process is known as gene manipulation or genetic engineering.

The transfer of genes from one organism to another occurs in nature through sexual reproduction, between organisms that are sexually compatible (i.e. closely related). In genetic engineering, the process is physical rather than sexual. The species do not have to be compatible (i.e. they can be completely different). For example, a gene from a plant can be transferred into the genetic make-up of an animal. Thus a plant species can be improved by introducing into its genetic material a desired gene from another organism. This process takes less time than traditional breeding and ensures that the desired gene alone is added to the genetic makeup of the crop plant.

To date, crop plants have been engineered genetically:

• To improve nutrient content (increased iron and Vitamin A, and to modify oil content).

• To be more tolerant to herbicide, drought and salt, and more resistant to disease and insect pest.

Some 40 species of crop plants so improved have been approved for commercial use internationally.

Research is in progress in the Caribbean on how the technology can be used to control bacterial spots that infect peppers and tomatoes.

There is concern in some quarters as to the safety of GM foods. What is not recognised is the fact that these foods undergo rigorous testing before they are approved for human consumption. Such testing is not normally carried out on foods produced by traditional means.

Biotechnology is …

Any technology that uses living organisms, or parts of living organisms, to make or modify products, to improve plants and animals, or to develop microorganisms for specific uses.

Biotechnology can improve plants by increasing:

• Yield volume

• Nutritional content

• Ability to resist insect pests and diseases caused by fungi, bacteria and viruses

• Ability to withstand harsh weather conditions

• Speed of the growth and maturing and fruit bearing processes

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