Lecture 1: Introduction to Agricultural Biotechnology PDF

Lec#1 Introduction to agricultural biotechnology, agribiotech products and practical applications in the filed Introduction to Agriculture Biotechnology Agriculture: Science or practice of farming, including cultivation of the soil for the growing of crops and the rearing...

Lec#1 Introduction to agricultural biotechnology, agribiotech products and practical applications in the filed Introduction to Agriculture Biotechnology Agriculture: Science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products. Biotechnology Use of living organisms or the products of living organisms to make a product or solve a problem for human benefit. "biotechnology" was first used in 1917 to describe processes using living organisms to make a product, such as industrial fermentations.  Stages of Biotechnology Development Ancient biotechnology early history as related to food and shelter; Includes domestication Old civilizations like Chinese, Greeks, Romans, Babylonians, and Egyptians, among many others have been involved in biotechnology since nearly (2000 BC)  Classical biotechnology built on ancient biotechnology; Fermentation promoted food production, and medicine Fermentation (to make bread, cheese, yogurt, beer and wines) Strain of bacterium: Saccharomyces cerevisiae  Modern biotechnology Manipulates genetic information in organism by genetic engineering Examples: Gene cloning Gene modification Gene manipulation  Types of Biotechnology A. Agricultural Biotechnology Agricultural Biotechnology is a range of tools, including traditional breeding techniques, that alter living organisms, or parts of organisms, to make or modify products; improve plants or animals; or develop microorganisms for specific agricultural uses. – United Nations Food and Agricultural Org (FAO) predicts by 2050, we will need to feed a world population of 9.1 billion! This requires raising food production by approximately 70%!  B. Animal Biotechnology The application of biotechnology to the processing or production of materials by animals to provide goods and services. Applications –Source of valuable antibodies Transgenic animals –Use as models in basic research Gene "knockout" experiments Design and testing of drugs and genetic therapies Source of transplant organs Gene knockout: Disrupt a gene in the animal and then look at what functions are affected in the animal as a result of the loss of the gene.This allows researchers to determine the role and function of the gene. Since, humans are similar to rats and mice, gene knockout studies in rats and mice can lead to better understanding of gene function in humans.  C. Microbial Biotechnology Any technological application that uses microbiological systems, microbial organisms, or its derivatives to make or modify products for specific use. Applications manipulation of microorganisms such as yeast and bacteria Create better enzymes More efficient decontamination processes for industrial waste product removal To produce large amounts of important proteins used in human medicine  D. Forensic Biotechnology is the application of science to criminal and civil laws, mainly on the criminal side during criminal investigation. When a crime is committed and the forensic team is called in, to investigate the spot. Applications –DNA fingerprinting Existence or rejection of a person from suspicion/doubt Paternity cases Tracking and confirmation of the spread of disease  Based on the gel results, there is evidence that the defendant/criminal committed the crime. The position of the bands as well as number of bands on the gel match with the victim's blood. It is important to note, that though the bands are very light for the sample from the jeans, they also match the victim's blood. Based on this gel, you CAN ONLY say that the defendant is linked to the crime scene.  E. Bioremediation The use of microorganisms to consume and break down environmental pollutants, in order to clean up a polluted site, Particularly those that contribute to environmental pollution Example 1989 Exxon Valdez oil spill in Alaska Adding nutrients to stimulate growth of bacteria that degrade components in crude oil spill  F. Blue/Aquatic Biotechnology The use of aquatic organisms such as finfish, shellfish, marine bacteria, and aquatic plants for biotechnology application is called aquatic biotechnology. It contributes to current or potential uses of marine products in various areas, including aquaculture and aquatic Biotech. Applications Disease-resistant strains of oysters Vaccines against viruses that infect salmon and other finfish  G. Medical biotechnology is the use of living cells and cell materials to research and produce pharmaceutical and diagnostic products that help treat and prevent human diseases Applications Gene therapy Stem cells Tissue engineering Genes induce human obesity Gene find to cause skin cancer Gene defect for muscle disorder identified Etc.  Agricultural Biotechnology? From centuries farmers have been improving wild plants and animals through the selection and breeding of desirable characteristics. This breeding has resulted in the domesticated plants and animals that are commonly used in crop and livestock agriculture. In the 20th century, breeding became more sophisticated due to the selection of different traits…etc.  Traits are passed from one generation to the next through genes, which are made of DNA. Virtually all crops improved with transferred DNA through biotechnology (often called GM crops. GMOs: an organism that expresses traits that result from the introduction of foreign DNA)  Goals of Genetic Engineering? Improvement of agronomically (soil management and field crop production) important crops Develop products with enhanced value. Develop organisms that express a “novel” trait not normally found in the species Pharmaceutically active compounds Development of stress tolerant plants  Important Plant Improvement Methods 1, Breeding 2, Biotechnology Conventional Selective Breeding Crossing between two species to produce a new, improved variety; not a biotechnology procedure Crossbreeding mates two sexually compatible species to create a new variety with the desired traits of the parents. Pollen from one plant is placed on the female part of another, which leads to a hybrid that contains genetic information from both parent plants. Crossbreeding can only be utilized within the same or closely related species. Limitations of conventional plant breeding Can take years Involve repeated backcrossing – Polyploid plants (multiple chromosome sets greater than normal) Increases undesirable traits, especially size Whole chromosomes can be transferred rather than single genes  Biotechnology Adding a gene from another species using the essential biotechnology procedure to produce transgenic through plant transformation. Plant transformation methods Protoplast fusion Leaf fragment technique Gene guns Antisense technology Advantages of plant Advantages transformation of Plant Transformationover conventional breeding over plant breeding 1. Transformation permits transfer of resistance genes between sexually incompatible species 2. Allows to generate novel types of resistance including the cases when natural resistance does not exist 3. Transformation is much less time consuming than breeding 4. Single transformation procedure permits insertion of multiple genes 5. Transformation works well for clonally propagated crops such as potato Desired trait are exported from a particular species of crop to an entirely different species. Transgene (is a gene transferred by any technique from one organism to another, while Endogenous gene is transferred from the same organism/spp.  Bacillus thuringiensis (Bt) Bacillus thuringiensis (Bt) is a gm+ soil bacterium that produces an insecticidal crystal protein from the cry genes. Bt crystal proteins are toxic to insects. When ingested, the Bt crystal toxin is activated by enzymes in the insect's gut. The activated toxin attaches to specific gut receptors, destroys cells in the gut wall, puncturing the gut and poisoning the insect. Gene Gun Is a device for delivering exogenous DNA to cells Procedure DNA is coated onto gold or tungsten particles Particles are accelerated at high speeds by the gun Particles enter plant tissue DNA enters the nucleus and incorporates into chromosome Useful in plants that are resistant to Agrobacterium  Insect resistance Insect resistant cotton – Bt toxin kills the cotton boll worm transgene = Bt protein Insect resistant corn – Bt toxin kills the European corn borer. transgene = Bt protein Normal Transgenic  Herbicide tolerance ▪ Weeds have proven to be an issue for farmers for thousands of years ▪ They significantly reduce crop yields due to compete for soil nutrients, water, sunlight and prove deadly to crops. ▪ Biotechnology has offered a solution in the form of herbicide tolerance.  Weeds can be controlled by spraying herbicide/s directly onto the crop plants. Herbicide could be coated on seed (like maize) and the maize would germinate and parasites such as Striga would be killed Resistance to synthetic herbicides has been GE into corn, soybeans, cotton, canola, sugar beets, rice, and flax. Herbicide resistant crops soybean, corn, canola transgene = modified EPSP synthase or phosphinothricin-N-acetyltransferase Herbicide resistant soybean (Roundup Ready) Turfgrass – herbicide resistance; slower growing (= reduced mowing) Virus resistance: Plants are susceptible to diseases caused by viruses, which are often spread by insects such as whitefly, aphids etc. Spread of viral diseases can be very Leafhopper difficult to control and crop damage can be severe. Insecticides are sometimes applied to control populations of transmitting Aphid insects, but often have little impact on the spread of the disease. Whitefly Virus resistance - papya resistant to PRSV in Hawaii USA transgene = virus coat protein Most effective methods against viral diseases are cultural controls or plant varieties bred to be resistant to the virus, but such strategies may not always be practically available. Plant biotechnology can provide resistance to viral disease where options were limited before. Researchers in USA developed two varieties of papaya resistant to Papaya ringspot virus (PRSV).  In the US, squash and zucchini resistant to different important viral diseases have been developed and commercialized. In South Africa first GMO maize has been commercialized against Maize streak virus In Brazil GMO bean has commercialized that is resistance against Bean golden mosaic virus. Sunflower – white mold resistance transgene = oxalate oxidase from wheat  Edible Vaccines ▪ Humans are “immunized” against the pathogen ▪ Humans eat the plant, and the body produces antibodies against pathogen protein Advantages of GE vaccines ▪ Heat-stable, don’t require cold-chain maintenance. ▪ Can be stored in seeds ▪ Need no purification  The Golden Rice Success Story –Genetically modify plants to produce beta-carotene –Beta Carotene is converted to vitamin A in humans –Vitamin A deficiency leads to poor vision and high susceptibility to disease ~70% of children