Food Production Macronutrients- carbohydrates, proteins and fats Micronutrients- vitamins (A, C, E) and minerals (iron, iodine, calcium) Chronic undernutrition:

Food ProductionMacronutrients- carbohydrates, proteins and fats

Micronutrients- vitamins (A, C, E) and minerals (iron, iodine, calcium)

Chronic undernutrition: not getting an adequate amount of calories

Chronic malnutrition: deficiency of key nutrients

Has been an improvement in the number of people facing chronic undernutrition around the world.

But in developing world 1 in 6 people still suffer from chronic undernutrition.

Green Revolution (starting in 1950’s)• Selectively bred crops (also know as artificial

selection) with higher yields.

• Inorganic fertilizers

• Pesticides

• Genetically- engineered crops

Genetically Modified Organisms:

Also known as Transgenic Organisms or Bioengineered Species

A biotechnology technique that allow genes from different species to be inserted into an organisms genome.

Example: Fish tomatoTomato with gene from flounder to reduce freezing.Was never commercially available

Gene splicing (joining two different pieces of DNA) relies on the use of restriction enzymes, which are natural occurring enzymes from bacteria whose function in bacteria is to cut up invading pieces of viral DNA.

Most restriction enzymes cut DNA in a way that leaves single stranded DNA ends (sticky ends).

Basics of Recombinant DNA Technology

The Process of Recombinant DNA1.Both a vector such as a

plasmid and a gene of interest are cut with the same restriction enzyme.

2.The complimentary sticky ends of the two different pieces of DNA allow them to be joined. DNA ligase forms bond.

3.Recombinant plasmid introduced into cell culture.

Examples of GMO crops

o Golden Rice: beta carotene gene from daffodils inserted into rice plants. Beta carotene can be converted into Vitamin A in the body.

o Round-up Ready (glyphosphate resistant): Gene for resistant to the herbicide is inserted to allow crops to be sprayed with the herbicide.

o BT crops: Gene for natural insecticide from bacteria Bacillus thuringiensis is inserted into crops.

Genetically Modified OrganismsProjected Advantages:

Projected Disadvantages:

Higher yields due to potential for improved characteristics such as resistance to insects, disease, frost etc.

Irreversible and unpredictable ecological effects.New allergens in foods

Improved quality of crop due to new characteristics: less spoilage etc.

Increase in pesticide- resistant insects, herbicide- resistant weeds etc.Can harm beneficial insectLower genetic diversity

Pesticide- general term for a substance that kills some type of unwanted pest.

TypesInsecticideHerbicide- kills weeds (plants)Fungicide- kills fungi (blight, mold, mildews and

rusts)

Pesticides1st Generation Pesticides- natural chemicals (esp. from plants)

2nd Generation Pesticides- starting with DDT in 1939

Broad-spectrum agent: Effective against a wide range of pestsBut also kill beneficial species.

Chlorinated hydrocarbons: such as DDT, dieldrin- persistent- biomagnfy

Organophosphates:such as malathion and parathion- not persistent and do not biomagnify- but are highly toxic

Narrow-spectrum agents: toxic to a more selective group of organisms.

Conventional Chemical PesticidesAdvantages: Disadvantages:Save lives (decreased malaria)

Kill natural pest enemies

Increased food supply

Can harm wildlife and peopleCan promote genetic resistanceExpensive to farmers- and cost can increase (pesticide treadmill)

The pesticide neonictinoid is suspected to be a primary cause of the bee colony collapse epidemic.

Pesticide TreadmillBecause: • a pesticide may kill beneficial insects that

would decrease pest population• Pests may develop resistance to pesticideFarmers often need to add increasing amounts of pesticide for it be effective.

Pesticide Regulations

Federal Insecticide and Fungicide Regulation Act (FIFRA), 1972

Overseen by EPA, USDA and FDA.EPA to assess new pesticides, but inadequate funds

Food Quality Protection Act, 1996Reduce levels of pesticide residues if inadequate information on pesticide’s safety.

• Pheromone Traps:Sticky traps with pheromones (chemical messages released by organism for mating signals or other communication) can be used to lure pests.

• Cultural Practices: “Fool the pest”- rotation of crops

• Biological controls such as beneficial insects

-Homes for pest enemies

• Hormones to disrupt pest life cycle

Alternatives to Pesticides

Integrated Pest Management:

- Combination of cultural, biological and chemical tools

- Monitoring of pests at economically tolerable level- Doesn’t use broad spectrum

pesticidesBrazil reduced pesticide usage by 90% using IPM