The document discusses the history and applications of agricultural biotechnology. It begins with the early domestication of crops by farmers selecting desirable traits over thousands of years. More recently, biotechnology has been used to develop crops with increased yields, disease resistance, and nutritional value. Examples discussed include Golden Rice, which was engineered to produce beta-carotene to address vitamin A deficiency, and the development of pesticide-resistant crops and plants that can serve as vaccines when ingested. The document also examines the use of biotechnology to improve animal health, create antibiotics, and enhance the traits of ornamental plants and flowers.
6. About 10,000 years BC, people
harvested their food from the
natural biological diversity that
surrounded them, and
eventually domesticated crops
and animals. During the process
of domestication, people began
to select better plant materials
for propagation and animals for
breeding.
7. Over thousands of years farmers selected for desirable traits in
crops, and thus improved the plants for agricultural purposes.
Desirable traits included crop varieties ( cultivars ) with shortened
growing seasons, increased resistance to diseases and pests,
larger seeds and fruits, nutritional content, shelf life, and better
adaptation to diverse ecological conditions under which crops
were grown.
8. Biotechnological Agriculture has undergone
tremendous changes, many of which have made
food and fiber production more efficient and
safer
For example in 1870, the total population of the
USA was 38,558,371 and 53% of this population
was involved in farming; in 2000, the total
population was 275,000,000 and only 1.8% of the
population was involved in farming.
10. Trichoderma spp., widely existing in nature,
are one of the main lignocellulose degrading
microorganisms.
They are a kind of bacteria commonly found
in soil, rotting wood, and other plant
organisms.
researchers have found Trichoderma spp.
can prevent and control many other plant
diseases. Because of the advantages of
nontoxicity to humans and animals, lack
of pesticide residue, and lack of pollution
to the environment.
11. Since the first time that Weindling found Trichoderma spp. had an
antagonistic role in regard to plant pathogenic bacteria
Currently, the most widely used agents are T. viride and T.
harzianum, mainly for the prevention and treatment of gray mold of
vegetables, wheat sheath blight, red bean root rot, and cotton
damping off..
13. (1) Competitive effects
The competitive effects of Trichoderma spp. concern the
competition for nutrients and for space. Because of the strong
saprophytic features, high adaptability, rapid growth, and
reproduction of Trichoderma spp., nutrition and space can be
used quickly, which plays an important role in the inhibition of
pathogenic fungi.
14. (2) Hyperparasitism
refers to a series of complex processes, including identification,
contact, twining, penetration, and parasitism. After the identification
of Trichoderma spp. to host pathogen, its hyphae can directly
invade or wrap around the host hyphae cell, penetrate the mycelia
of the pathogen, and absorb nutrients by secreting extracellular
enzymes to dissolve the cell walls, which causes the enlargement,
deformation, or shrinkage of the pathogen cell, the contraction of
protoplasm, and the rupture of the cell wall.
15. (3) Antibiosis
Trichoderma spp. can produce antagonistic chemicals against
plant pathogens in their metabolic processes, including
antibiotics and enzymes, such as trichodermin, neomycin,
green trichodermin, and antimicrobial peptides.
16. The main applications are as follows:
① soil treatment.
② seedling and corm processing.
③ aboveground application to prevent and control disease.
④ fine strains and strain combination screening.
⑤ the mixed applications of a small amount of fungicide.
⑥ antagonistic substance extraction, purification, and activity
assay.
19. Improving the nutritional value of Golden Rice
through increased pro-vitamin A content
Golden Rice' is a variety of rice engineered to produce beta-carotene
(pro-vitamin A) to help combat vitamin A deficiency1, and it has been
predicted that its contribution to alleviating vitamin A deficiency would be
substantially improved through even higher beta-carotene content2. We
hypothesized that the daffodil gene encoding phytoene synthase (psy),
one of the two genes used to develop Golden Rice, was the limiting step
in beta-carotene accumulation. Through systematic testing of other plant
psys, we identified a psy from maize that substantially increased
carotenoid accumulation in a model plant system. We went on to
develop 'Golden Rice 2' introducing this psy in combination with the
Erwinia uredovora carotene desaturase (crtI) used to generate the
original Golden Rice1. We observed an increase in total carotenoids of
up to 23-fold (maximum 37 mug/g) compared to the original Golden Rice
and a preferential accumulation of beta-carotene.
20.
21.
22. Antibiotics:
Plants are used to create antibiotics for both human and animal use,
is less expensive than traditional antibiotic production, but this
practice raise many bioethics issues, because the result is
widespread, possibly needless use of antibiotics which may
encourage expansion of antibiotic-resistant bacterial strain.
23. Flowers :
use of gene recognition and transfer techniques to improve the color, smell, size
and other features of flowers.
biotech has been used to make improvement to other common ornamental
plants, in particular, shrubs and trees. Some of these changes are similar to
those made to crops, such as enhancing cold confrontation of a breed of
tropical plant.
24.
25. Plant and Animal Reproduction :
• Enhancing plant and animal behavior by traditional methods like
cross-pollination, grafting, and cross-breeding is time-consuming.
Biotech advance let for specific changes to be made rapidly, on a
molecular level through over-expression or removal of genes, or
the introduction of foreign genes.
26.
27. Vaccines :
Oral vaccines have been in the works for many years as a possible
solution to the spread of disease in underdeveloped countries, where
costs are prohibitive to widespread vaccination. Genetically engineered
crops, usually fruits or vegetables, designed to carry antigenic proteins
from infectious pathogens.
28. that will trigger an immune response when ingested. An example of
this is a patient-specific vaccine for treating cancer. An anti-
lymphoma vaccine has been made using tobacco plants carrying
RNA from cloned malignant B-cells. The resulting protein is then
used to vaccinate the patient and boost their immune system
against the cancer. Tailor-made vaccines for cancer treatment have
shown considerable promise in preliminary studies.
29. Improve animal health :
Better detecation of disease
More nutritious feed
New and more effective vaccines
Improve treatment for diseases
30. Pesticide-Resistant Crops :
Not to be confused with pest-resistance
these plants are tolerant of ,
allowing farmers to selectively
kill surrounding weeds without
harming their crop. The most famous example of this is the
Roundup-Ready technology, developed by Monsanto.
31. First introduced in 1998 as GM soybeans, Roundup-Ready plants
are unaffected by the herbicide glyphosate, which can be applied
in copious quantities to eliminate any other plants in the field.
32. The benefits to this are savings in time and costs associated with
conventional tillage to reduce weeds, or multiple applications of
different types of herbicides to selectively eliminate specific species
of weeds. The possible drawbacks include all the controversial
arguments against GMOs.
(GMO stands for genetically modified organism. The acronym can
apply to plants, animals or microorganisms, whereas the term
genetically engineered microorganism (GEM) refers only to
bacteria, fungi, yeast or other microorganisms.)