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C. S. PrakashCenter for Plant Biotechnology
ResearchTuskegee University, Alabama, USA
Bioengineered CropsBioengineered Crops--Benefits and Risk Benefits and Risk
AssessmentAssessment
Crop Evolution and Human CivilizationCrop Evolution and Human Civilization• Humans Have Always Guided the
Evolution of Crops!• A small sample of wild plants were chosen and
domesticated• 10,000 years of Selection.• All crops we grow today were once wild plants.
But no crop would survive in the wild any more.• Crops, strains and genes have moved around
the globe.
Improving Our Crop PlantsImproving Our Crop Plants• Developing Modern
Varieties of Crops– Hybridization
• Crosses with Wild Relatives• Hybrids
– Mutation • Irradiation• Chemicals
– Cell Culture• Embryo Rescue• Somaclonal variation
Modern Genetic ModificationModern Genetic ModificationInserting one or few genes to
achieve desired traits.
Transfer of Genes into Crop PlantsTransfer of Genes into Crop Plants– Relatively Precise and PredictableRelatively Precise and Predictable– Changes are SubtleChanges are Subtle– Allows FlexibilityAllows Flexibility– ExpeditiousExpeditious
Desired gene
Traditional plant breedingDNA is a strand of genes, much like a strand of pearls. Traditional plant breeding combines many genes at once.
Traditional donor Commercial variety New variety
Desired Gene
X =(crosses)
(many genes are transferred)
Plant biotechnologyUsing plant biotechnology, a single gene may be added to the strand.
Desired gene Commercial variety New variety
(transfers)
=
Desired gene
(only desired gene is transferred)
Dominant GM CropsDominant GM Crops• Herbicide Tolerant Soybean 41.4• Bt Maize 9.1• Herbicide Tolerant Canola 3.6• Bt/Ht Maize 3.2• Ht Maize 3.2• Bt Cotton 3.1• Bt/Ht Cotton 2.6• Ht Cotton 1.5
In Million HectaresSource: Clives James, 2003. ISAAA.org
USA: Overall impact of USA: Overall impact of biotechnologybiotechnologyin crop and pest managementin crop and pest management
70 m kg a.i.$2.5 billion6 b kgTotal
50 m kg a.i.$1 billion4 b kgFuture Crops (32)
20 m kg a.i.$1.5 billion2 b kgCurrent Crops(8)
Pesticide Reduction
Economic Impact
Yield Increase
Crop
Source: Gianessi et al. (2002). NCFAP
Biotechnology Can Add Value to Global Agriculture
• Environmental Impact - Decreased Use of Pesticides
• Reduce Losses from Pests and Diseases
• Improve Nutrient Efficiency• Improve Productivity
Cotton• China, South Africa….India,
Egypt, Indonesia.. 60 million people in India dependent on cotton
• Losses due to Bollworm $1.5 billion in India and China
• 2 million gallons of pesticide saved in US alone using Bt Cotton
• Cotton - 50% of the total pesticides
• Bt Cotton - yield increases up to 40%. • Million Chinese farmers grew it• Savings up to $182 per hectare • Spraying reduced from 12 to 1• Both private and public sector
Benefits of Biotechnology…..• Post Harvest Quality - Prolong
Shelf Life of Fruits, Vegetables and Flowers
• Extend Crop Area and Season • Stress Tolerance - Drought,
Acidity, Salinity, Heat. Flooding
Golden RiceGolden Rice• Milled rice has no beta-carotene• Vitamin A deficiency - 200 million
children and woman• About 500,000 children go blind
(60 every hour!)• 2 million children die each year• Golden Rice may provide one of
the many solutions• Still Many Years Away from
Reality
Ingo Potrykus (Switzerland) and Peter Beyer (Germany)
Enhancing Food and Agriculture
• More Nutritious Food• Healthy Produce. Low Toxins• Pharmaceutical Proteins• Clean Up Environment• Industrial Products• Value-Added Products
Why Biotechnology?
• Expedient• Knowledge-Based Approach • Offers Unique Solutions• Integrates Technology Delivery• Scale Neutral• Does not Displace Traditional Methods• Environmentally Friendly• Portable - Across Crops• Versatile - Impact on All Facets of Food
Chain from Producers to Consumers
Are GM Foods Safe?
Genetically Modified (GM) food is as safe or even safer than conventionally produced food
GM foods represent a very minor, precise and known change
GM foods are subject to intense pre-market testing
GM foods are subject to stringent regulatory oversight
Safety of GM Foods…
•Every Product Tested on Case-by-Case• Over Billion Acres Grown Since 1996• More than 10,000 Food Products Contain GM• Not One Single Instance of Hazard• Dozens of Scientific Societies and International organizations attest to the safety
EPAEPAFDAFDA**
Regulatory Systems in the U.S.
USDAUSDA
Field testingpermitsnotifications
Determination of nonregulated status
Food safety
Feed safety
Pesticidal plantstolerance exemptionregistrations
Herbicide registration
* Voluntary Con-sultation process forsubstantially equi-valent products.
Regulation of GM Crops and Food
• The Department of Agriculture (USDA), through its Animal and Plant Health Inspection Service (APHIS), oversees field testing of biotech seeds and plants to make sure their release causes no harm to agriculture and the environment.
• The Food and Drug Administration (FDA) assesses the safety of all biotech plant products intended for consumption by humans and animals.
Regulation of GM Crops…
• The Environmental Protection Agency (EPA) evaluates biotech plants' environmental safety — such as their pesticide properties, possible effect on wildlife and how these plants break down in the environment. The agency also must approve any herbicide use with herbicide-tolerant crops.
Safety Testing of GM Crops
Phase II Phase II
Biological / agronomic Biological / agronomic equivalenceequivalence
Stringent agronomic Stringent agronomic performance and efficacy performance and efficacy criteriacriteria
Greater than 99% of all Greater than 99% of all events are eliminatedevents are eliminated
Key step in product Key step in product evaluation for conventional evaluation for conventional varietiesvarieties
Phase III Phase III
Detailed product safetyDetailed product safety FoodFood FeedFeed EnvironmentalEnvironmental
Phase I Phase I
Safety of gene, protein, cropSafety of gene, protein, crop Choice of genes / proteinsChoice of genes / proteins
- mechanism of action- mechanism of action Source of genesSource of genes
– history of safe usehistory of safe use– ethicsethics
Environmental / ecological Environmental / ecological considerationsconsiderations
PostMarket
Transfor- mation
LineSelection
VarietyDevelopment
FieldProduction
MarketGeneDiscovery
GH & FieldEvaluation
ProductConcept
DiscoveryDiscovery Line SelectionLine Selection Product AdvancementProduct Advancement
Substantial Equivalence - Evaluation
PHENOTYPE
•Morphology
•Agronomic
•disease resistance
•drought resistance
•yields
•Organoleptic
COMPOSITION
•Macronutrients
•AA composition
•FA composition
•Anti-nutrients
•Toxic substances
•Allergens
•Specific constituents
SAFETY ASSESSMENT
•Toxicity
•Allergenic potential
•Nutritional
FEED EQUIVALENCE
•Performance
Compositional Equivalence
• Evaluate Key
• - Nutrients
• - Vitamins
• - Minerals
• - Anti-nutrients
• - toxicants
• - Allergens
• - Others
List depends
on crop
GrainGrain ForageForage- Protein- Protein - Protein- Protein
- Fat- Fat - Fat- Fat
- Fiber- Fiber - Fiber- Fiber
- Starch- Starch- Amino acid composition- Amino acid composition- Fatty acid composition- Fatty acid composition
- Ash- Ash
- Sugars- Sugars
- Calcium- Calcium
- Phosphorous- Phosphorous
OECD Consensus Documents
Environmental IssuesWhat are the Ecological
Effects of New Crops?
• Effect on Biodiversity? - non-target organisms
• Gene flow - Superweeds • Horizontal Transfer• Durability of Resistance
Potential Impacts of GM crops on the Environment
Direct:• Non-target effects of insect resistance• Fate and consequence of insecticidal toxins in soil• Persistence in agricultural habitat (weediness)• Invasiveness in natural habitats• Transfer of herbicide tolerance to weeds• Transfer of biotic and abiotic stress tolerance to • weeds or feral species• Stacking of herbicide tolerance genes
Adapted from P.J. Dale, B. Clarke and E.M.G. Fontes, 2002. Nature Biotechnology.
Potential Impacts of GM crops on the Environment
Indirect:
• Development of weeds tolerant to herbicides by evolution and selection• Development of resistance to Bt toxins in pests• Effects of broad-spectrum herbicides• Change in herbicide use• Change in soil cultivation patterns
Adapted from P.J. Dale, B. Clarke and E.M.G. Fontes, 2002. Nature Biotechnology.
Continued Monitoring of GM Crops for Environmental Effects
• Insect Resistance Loss
• Effect on Non-target Organisms
• Beneficial environmental effects (e.g. increases in bird populations)
• Effects on biodiversity
• Gene flow data
If Europe Adopted GM Crops…
• Nine GM crops could increase yields by 8.5 billion kilograms per year
• Increase grower net income by EUR 1.6 Billion per year
• Reduce pesticide use by 14.4 million kilograms per year compared with existing practices.
Source: NCFAP.org
Why Public Anxiety with Biotech Crops?
• Societal Concern About Biotech is Understandable!– Strong Assurance of Safety Needed– Unfamiliar with the Technology– Lack of Reliable Information– Unaware of Safeguards– Negative Media Opinion– Opposition by Activist Groups– Mistrust of the Industry
Scientific Community has neither addressed public concerns nor communicated the value of this technology effectively
Major Barriers to Agbiotech
• Regulatory Environment
• Trade Barriers
• Public Perception
• Environmental Activism
• Negative Media Portrayal
• Food Industry and Retailers
• Organic Food Industry
Promoting Food Biotechnology
• Enabling Policies
• Harmonization of regulation
• Science-based regulation
• Address Trade Barriers
• Increased R&D Funding
• Education and Outreach
www.agbioworld.orgwww.agbioworld.orgwww.agbioworld.orgwww.agbioworld.org
Is Biotechnology the Sole Answer Is Biotechnology the Sole Answer to Global Food Problems?to Global Food Problems?
• No Single Solution is a Panacea or ‘Cure-All’
• One Tool in a Toolbox• World Hunger - Myriad Reasons• Can Only Work with Other
Traditional Approaches• We must weigh all options.
Choose the Most Effective Solution
www.agbioworld.orgwww.agbioworld.orgwww.agbioworld.orgwww.agbioworld.org
“Change is Inevitable, Progress is Optional”