Video clip – Norman Borlaug and selective breeding of wheat

This video clip from the BBC TV series Botany: A Blooming History introduces the American scientist Norman Borlaug, the man behind the ‘green revolution’ credited with saving over a billion people from starvation.

Norman Borlaug using selective breeding techniques to improve wheat production in Mexico. He produced plants which had large seed heads and hence a good yield. However the plants were too tall and were prone to falling over (lodging). A mutant dwarf form of wheat was discovered in post-war Japan. Borlaug crossed this strain with the high yield variety and produced a strong, high yielding wheat. This was subsequently grown throughout the world, and has reduced the levels of hunger on several continents. The innovation was called the ‘Green revolution’. The cost issues related to growing this wheat are mentioned briefly and the question of sustainability is raised.

Illustrate the importance of selective breeding, with discussion of the features which were selected and the resultant hybrid. Students could then look at other crop plants which have been selectively bred and discuss selected phenotypes. The material is also a stimulus for the discussion of how science can contribute to human well-being. Discuss the risks associated with the growing of monocultures, excessive use of fertilisers, the costs of using chemicals on foods etc.