Introduction to Plant
Biotechnology
PlSc 452/552 Lecture 1
Chapter 1
C. Neal Stewart, Jr.
plantsciences.utk.edu/stewart.htm
nealstewart@utk.edu
Rules for class
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Do the readings
Proper preparation prevents poor performance
Ask lots of questions
Give lots of answers
All opinions and thoughts will be heard and
respected
• Grades are not awarded on the basis of need
Have fun!
Questions for the semester
• What is/are genetic engineering, transgenic
plants, biotechnology?
• What is the current and potential
applications?
• Risks?
• Benefits?
• How does plant biotechnology fit in with
modern plant breeding and agriculture?
Objectives and questions
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Define plant biotechnology.
What biotech crops are grown and where?
Why do farmers grow transgenic crops?
How has the adoption of plant
biotechnology impacted the environment?
• What has been plant biotech’s impact in the
US and in developing countries?
Central dogma: DNARNA
protein
Transgenic plants-
Agrobacterium
Any gene, any organism
The new plant will pass the transgene
to its progeny through seed.
Biolistics
Plant biotech milestones
• 1962 Murashige and Skoog publish their
paper on tissue culture media that is very
effective for tobacco and other plants
• 1982 First stably transgenic plant—marker
gene in tobacco
• 1987 Gene gun invented
• 1994 Flavr Savr tomato commercialized
• 1996 First wide-scale planting of soybean
and corn
• 2006 Billionth acre of transgenic crop
planted somewhere in the world
• 2011 Second billionth acre planted
Herbicide tolerant soybean
Bt corn
Bt cotton
Progression of transgenic plants
• 1st Generation: Input traits (herbicide
tolerance, insect resistance, etc.)
• 2nd Generation: Output traits:
(pharmaceuticals, enhanced nutrition, etc.)
• 3rd Generation: Non-ag– (phytoremediation,
sentinels, detectors)
Environmental benefits
Herbicide tolerant crops have increased and
encouraged no-till agriculture– less soil erosion.
Over 1 million gallons of unsprayed insecticide per
year.
Dr. Norman Borlaug
Nobel Peace Prize 1970
Father of the Green Revolution
1914-2009
Environmental Impact Quotient
(EIQ)
•Assessment of pesticide active ingredient used
•Assessment of the specific pesticides used
•Provides environmental impacts of individual pesticides into
a single ‘field value per hectare’.
•Balanced assessment of the impact of GM crops on the
environment
• Includes key toxicity and environmental exposure data
•related to individual products
•applicable to impacts on farm workers
•consumers and ecology
•consistent and comprehensive measure of environmental
impact.
(Kovach et al. (1992)
EIQ example
The EIQ value is multiplied by the amount of pesticide
active ingredient (ai) used per hectare to produce a field
EIQ value.
For example, the EIQ rating for glyphosate is 15.3. By
using this rating multiplied by the amount of glyphosate
used per hectare (eg, a hypothetical example of 1.1 kg
applied per ha), the field EIQ value for glyphosate would
be equivalent to 16.83/ha.
In comparison, the field EIQ/ha value for a commonly
used herbicide on corn crops (atrazine) is 22.9/ha.
Recap and answers
• Plant biotechnology: molecular manipulation of
plants and cells.
• What biotech crops are grown and where? Row
crops soybean and corn for herbicide tolerance
and insect resistance. US but also in 27 other
countries.
• Why do farmers grow transgenic crops? More
efficient and effective; better control of pests.
• How has the adoption of plant biotechnology
impacted the environment? Positive—less
insecticides, less soil erosion.
• What has been plant biotech’s impact in the US
and in developing countries? Changed row crop
genetics in US and is improving yeilds in
international agriculture.
But…GM crops not universally
accepted and grown. Why?
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Misunderstandings
Politics
Immature regulatory structures
Consumer issues
Benefits unclear to consumers
Fear of unknown, risk perception
Science and education should help
“Ordinary Tomatoes Do Not Contain Genes,
while Genetically Modified Ones Do”
52
Canada
33
45
United States
45
34
Austria
22
32
France
36
Italy
35
44
29
20
44
44
51
Netherlands
27
22
24
30
48
21
31
40
0
21
46
Switzerland
United Kingdom
10
39
Germany
Sweden
15
20
38
40
22
60
80
Percent Response
1996 - 1998
False (Correct)
Source: Tom Hoban
Don't Know
True
100
“I eat organic food and drink only green
tea– gallons of it when I’m writing. I
smoke cigarettes, but organic ones”*
Discussing her “healthy” lifestyle in Organic Style magazine March 2005.