Biotechnology In Agriculture (Unit 2)

Front 1

What is the definition of biotechnology?

Back 1

Any technological application that uses biological systems, living organisms, or derivatives thereof, to make or modify products or processes for specific use

Front 2

What is biotechnology in agriculture?

Back 2

Biotechnology in agriculture involves the manipulation of genes to create a new strain of plants that have the desired trait.

Front 3

What is a GMO?

Back 3

A genetically modified organism (GMO) is one whose genetic material has been altered using genetic engineering techniques. In most cases, a transgene is inserted into the genome of an organism. It is also possible to alter the gene inside the genome of the organism itself. The organism that carries a transgene is called a transgenic organism.

Front 4

How do you create a GMO?

Back 4

1. Find an organism expressing the trait of interest.

2. Isolate the genes responsible for the trait.

3. Insert the gene into a target organism.

4. Regenerate an entire organism from the transformed cell.

Front 5

Traditional method vs biotechnology

Back 5

Traditional plant breeding method involved artificially crossing plants within the same species or closely related species to bring different genes together. The transfer of genes is non-specific and takes a very long time to achieve.

Biotechnology allows the transfer of specific genes encoding the desired traits into target plants in a more precise and controlled manner within a short period.

Front 6

What are the reasons for manipulating the genetic make-up of crops?

Back 6

To improve yields.

To improve resistance to cold, drought and salinity.

To increase tolerance to a herbicide.

To improve resistance to pests and diseases.

To enhance the nutritional content of foods.

Front 7

Cold tolerance

Back 7

Unexpected frost can destroy seedlings and the quality of frozen fruits or vegetables can be compromised by the damaging effects of ice crystal formed within the frozen tissue.

Scientists have created frost-resistant tobacco and potato plants by inserting an antifreeze gene from a cold-water fish, such as Flounder, a fish that can survive in very cold conditions.

These transgenic plants are able to tolerate cold temperatures and frost that normally would kill unmodified seedlings.

Front 8

Herbicide resistance

Back 8

Farmers often spray large quantities of different herbicides to destroy weeds.

Herbicide-tolerant crops are created by inserting transgene taken from a bacterium.

The transgenic crops can now produce a protein that makes them resistant to the herbicides glyphosate (marketed as RoundupⓇ by Monsanto Company) and glufosinate (marketed as LibertyⓇ by Bayer).

Herbicide-resistant crops currently on the market include corn, cotton, canola, soybean, sorghum and alfalfa

Front 9

Benefits of herbicide resistant plants

Back 9

These herbicides are broad-spectrum, meaning that they kill nearly all kinds of plants except those that have the tolerance gene. So, a farmer can apply a single herbicide to his fields of herbicide-tolerant crops.

Another important benefit is that this class of herbicides breaks down quickly in the soil hence reducing agricultural waste run-off and pollution of the water supply.

Front 10

Bt insect-resistant crops

Back 10

Traditionally, Bt toxin powder was sprayed onto the plants to kill the insect larvae, but the powder can be washed off by rain and break down easily when exposed to sunlight.

With the advancement of biotechnology, Bt genes have been transferred to crops enabling them to produce their own toxins against pests.

Insertion of the Bt genes directly into the genome of crops allowed the crops to constantly produce Bt toxin proteins in all tissues of the plant.

When an insect larva eats the plant tissue, it also consumes the toxins which will cause the intestines to rupture, thus killing it.

Bt insect-resistant crops currently on the market include corn and cotton.

Front 11

Advantages and disadvantages of Bt insect-resistant crops

Back 11

The corn is not meant for human consumption, but used as a pig fodder since the only advantages held would be:

the lack of pesticide residues on foods, reduction of pesticide leaking into groundwater

minimization of farm worker exposure to hazardous pesticides

while the disadvantages are:

the loss of agricultural biodiversity when farmers choose to grow only GM crop and

the emergence of unexpected new allergens due to new proteins found in the food.

Front 12

Golden rice

Back 12

Golden rice is a variety of Oryza sativa rice produced through genetic engineering to biosynthesize beta-carotene, a precursor of vitamin A, in the rice grain.

The development was intended as a solution to the problem of vitamin A deficiency, which is a significant cause of blindness among children globally.

The beta-carotene is converted to vitamin A in our cells when taken into our body.

It is created by introducing three genes into the genome of rice plants, two from daffodil plants and one from soil bacterium, so that the orange pigment beta-carotene can be produced in rice grains.

Front 13

Risk and Concerns of GM foods

Back 13

Human health:

Allergenicity- introducing a foreign gene into a plant and hence the production of a new protein not naturally present in the plant may trigger allergic reactions in susceptible individuals.

Unknown effects on human health over long-term consumption.

Skepticism about the quality of tests on GM foods and questioning of the accuracy of the results.

Vegetarians object to animal-based transgenes.

Natural environment:

Unintended harm to other organisms- pollen from Bt corn blown by wind onto milkweed plants in neighbouring fields killed Monarch butterfly caterpillars, which are not pests, that fed on the milkweed plants.

Pests may develop resistance to Bt toxin over time.

Gene transfer to non-target species- transgenic herbicide-resistant crop and weeds cross-pollinated, resulting in “superweeds”. The “superweeds” acquired the herbicide-tolerant gene as well.

Economic:

Farmers in poor countries may not have money to buy transgenic seeds. If transgenic crops prove to be cheaper or more productive, the farmers in poor countries would find it difficult to sell their non-transgenic crops.