t into the plant chromosome through biolistics, vectors, or protoplast transformation (Horsch 1993). Biolistics is a technique that shoots the gene block into the potential host cell. In order for the process to succeed, the microscopic particles and DNA must enter the cell nuclei and combine with the plant chromosome. Biolistics is commonly used but has a slight failure risk since the breeder has little control over the destination of the gene block (Mooney & Bernardi 1990). Bacteria or viruses can also carry the gene blocks into a new cell. Common vectors in gene transfer between plants are Agrobacterium tumefaciens and Agrobacterium rhizogenes. In the soil, the bacteria will infect the plants with their own plasmid, transferring the desired gene that was placed in the bacteria’s DNA. Vector gene transfer is a preferred method of transformation since this modification already occurs naturally in the environment (Rudolph & McIntire 1996). Last is protoplast transformation, which uses enzymes to dissolve the cellulose in the plant wall that leaves a protoplast. Once a specific gene block is added to the protoplast, the cell wall will re-grow into a transgenic plant. Direct manipulation of DNA focuses on selective breeding, altering organisms to achieve higher quality products and more of them. These improved crop modifications center either on agronomic traits or quality traits (Nielsen 1999). Reductions of herbicides, insecticides, and water usage are some effects of replacing plants with desired properties. Farmers choose these agronomic traits to reduce their costs of poisons and water, therefore increasing profitability. Quality traits focus more on the consumer of the product. By improving product characteristics such as phenotype, nutritional value, and preservation, consumers will benefit. In return, agricultural industries will be able to sell products at a higher price and increase their profit in the...
