Plant Biotechnology PDF

 help address the challenge of producing more food ad more nutritious food, more effectively than was previous possible. Why plant biotech? Focus of plant biotech Economic Environment Focus of plant biotech Health Society  Milestones of plant biotech The principles of...

 help address the challenge of producing more food ad more nutritious food, more effectively than was previous possible. Why plant biotech? Focus of plant biotech Economic Environment Focus of plant biotech Health Society  Milestones of plant biotech The principles of inheritance – 1865 Pure line theory – 1903 Hybrid vigor – 1908 The double-cross method – 1917 Transposable elements discovered in maize – 1940’s  Milestones of plant biotech Agrobacterium- mediated plant transformation – 1977 The first biotech plant – 1982 The gene gun method - 1986  Milestones of plant biotech The first flowering plant genome sequenced – 2000 The first Golden Rice field trial – 2004 CRISPR first applied to plants – 2013  Transgenic plant DNA is modified using genetic engineering techniques. AIM: introduce a new trait to the plant which does not occur naturally in the species improving shelf life higher yield improved quality pest resistance Herbicide tolerant tolerant to heat, cold and drought resistance biotic and abiotic stresses tolerant Development of transgenic crops  Particle bombardment Transformation by Gene Gun Method Blast tiny metal beads coated with DNA into an embryonic plant cell Concept of gene gun Golden rice In vitro culture – tissue culture wherein fragments of a plant tissue are introduced into a new, artificial environment, so they continue to function - Seed culture or grow. - Embryo culture - Callus culture - Organ culture - Protoplast culture  Major steps of plant tissue culture Initiation phase tissue of interest is obtained and introduced and sterilized. It is during this stage that the tissue is initiated in to culture. Multiplication phase in vitro plant material is re- divided and then introduced in to the medium. Rooting formation roots are formed. hormones are required in order to induce rooting, and consequently complete plantlets. Plant breeding Manipulation in order to create desirable genotypes and phenotypes for specific purpose. Pollination Genetic engineering ○ Artificial selection of progeny Plant breeding was described by Nikolai as “evolution directed by man.” Methods of plant breeding Hybridization Self pollinated species Outcrossing Breeding enhancement Doubled haploidy Mark assisted selection Mutation breeding Double haploidy every plant species produces haploid gametes during meiosis. Haploid gametes are found in (egg) and in pollen tissues. double the chromosomes in their nuclei to produce a cell type that is both diploid and homozygous. Marker-assisted selection (MAS) selecting specific alleles at marker loci that are known to be linked to the genes that cause the desired trait. MAS advantage 1) avoids errors caused by environmental variance 2) can be applied at a juvenile stage before a trait is expressed 3) can be applied on a single plant, whereas phenotypic selection of some traits might require seed or tissue from many plants to be effective 4) may be less expensive than phenotypic selection Mutation breeding Mutations are genetic modifications that occur in the DNA of plants, producing new alleles that are different from the alleles that the plant inherited from its parents. Artificially induced at higher frequency than natural rate. Radiation Chemical induction