2.4 FOOD ENGINEERING

Have you ever eaten genetically engineered foods?

Most likely, yes. The majority of the corn in the United States is genetically engineered. Corn syrup is used to sweeten many things, like this Coke. Corn is also fed to the cows that provided this hamburger.

Biotechnology in Agriculture

Biotechnology is changing the genetic makeup of living things to make a useful product. Biotechnology has led scientists to develop useful applications in agriculture and food science. These include the development of transgenic crops. In transgenic crops, genes are placed into plants to give the crop a beneficial trait. Benefits include:

  • Improved yield from crops.
  • Increased resistance of crops to environmental stresses.
  • Increased nutritional qualities of food crops.
  • Improved taste, texture or appearance of food.
  • Reduced dependence on fertilizers, insecticides, and other chemicals.

Crops are obviously dependent on environmental conditions. Drought can destroy crop yields, as can too much rain and floods. But what if crops could be developed to withstand these harsh conditions?

Biotechnology will allow the development of crops containing genes that will help them to withstand harsh conditions. For example, drought and salty soil are two significant factors affecting how well crops grow. But there are crops that can withstand these harsh conditions. Why? Probably because of that plant’s genetics. So scientists are studying plants that can cope with these extreme conditions. They hope to identify and isolate the genes that control these beneficial traits. The genes could then be transferred into more desirable crops, with the hope of producing the same traits in those crops.

Thale cress (Figure below), a species of Arabidopsis (Arabidopsis thaliana), is a tiny weed that is often used for plant research, because it is very easy to grow, and its DNA has been mapped. Scientists have identified a gene from this plant, At-DBF2, that gives the plant resistance to some environmental stresses. When this gene is inserted into tomato and tobacco cells, the cells were able to withstand environmental stresses like salt, drought, cold, and heat far better than ordinary cells. If these results prove successful in larger trials, then At-DBF2 genes could help in engineering crops that can better withstand harsh environments.

Thale cress (''Arabidopsis thaliana'')

Thale cress (Arabidopsis thaliana).

Vocabulary

  • Arabidopsis (Arabidopsis thaliana): Tiny weed that is often used for plant research, because it is very easy to grow, and its DNA has been mapped.
  • biotechnology: Changing the genetic makeup of living things to make a useful product.
  • transgenic: Containing a gene transferred from another organism.

Summary

  • Transgenic crops have extra genes that were placed into them to give the crop a beneficial trait.
  • In the future, crops may be genetically altered to withstand harsh conditions.

Practice

Use the resources below to answer the questions that follow.

  1. What approach do scientists use to disable genes in Arabidopsis? How does this work? Be as specific and complete in your answer as you can.
  2. What do scientists use to insert DNA into Arabidopsis? How does this work?
  3. Can scientists insert whole genes into Arabidopsis? How is this situation useful for agriculture? Explain your answer as fully as you can.
  4. How are the Araidopsis mutants valuable to botanists in general?
  1. What are the purported environmental benefits to using biotechnology in agriculture?
  2. What are the purported environmental dangers to using biotechnology in agriculture?
  3. What is the purported societal benefit to using biotechnology in agriculture? Can you think of any others?
  4. What is the purported societal danger to using biotechnology in agriculture? Can you think of any others?

Review

  1. What is a transgenic plant?
  2. What are some examples of how biotechnology might be used in agriculture?

Leave a comment