Week 9 - Page 1 of
October 22, 2007
BIOL 101 - Fall 2007 -Week 9 - Plant genetic engineering: Feeding the world
Genetically modified organisms (GMOs) - What they are and Why they are needed?
According to the United Nations (UN), the 2007 world population is around 6.6 billion. By
the end of 2050, the world population is projected to hit 9.2 billion, with most of the population
increase being in less developed regions such as Africa, Asia (except Japan), Latin America, the
Caribbean, Melanesia, Micronesia and Polynesia. Population growth in more developed regions,
such as Japan, Europe, North America, Australia and New Zealand is relatively slow
UN’s Food and Agriculture Organization (FAO) definition of food security: Food security exists
when all people, at all times, have access to sufficient, safe and nutritious food to meet their dietary
needs and food preferences for an active and healthy life.
Major issues surrounding food security
in the world:
Unequal rate of population growth between different regions around the world.
Unequal food production and distribution between different countries/ different regions within
Climates, pests and diseases contribute to the quantity and quality of food production.
Economic situation and political stability of different countries affect overall food distribution
around the world.
Three approaches to improve crops production
: This involves crosses between closely related crop species with desirable
traits in an attempt to screen for a plant exhibiting “hybrid vigor”; i.e., one that has better overall
traits than its parents. Such traits include yield or tolerance to unfavorable environmental conditions.
: This involves the use of physical (X-ray irradiation) or chemical mutagens
(e.g. EMS - ethyl methane sulfonate) to create mutant crop plants that show desirable traits.
Mutation breeding has been practiced for more than 70 years.
: This involves the use of recombinant DNA technology to transfer a gene
of interest from one organism to another. The gene of interest usually encodes a protein that confers
a desirable trait, such as insect/ herbicide resistance, to the target organism (e.g. crop).
Norman E. Borlaug - Father of the Green Revolution
University. He was awarded the Nobel Peace Price in 1970 for his contributions to the development
of dwarf wheat varieties that resist a wide spectrum of plant pests and diseases and produce two to
three times more grain than the traditional varieties. As a result of Borlaug’s and his colleagues’
work, in Pakistan, wheat yields rose from 4.6 million tons in 1965 to 8.4 million in 1970. In India,
they rose from 12.3 million tons in 1965 to 20 million in 1970 and up to 73.5 million tons in 1999