Transgenic Plants

Transgenic plants are produced by introducing a foreign gene into a plant’s genome. These plants can be developed for a variety of reasons, including virus or pest resistance, higher yield, or therapeutic protein production.

To produce a transgenic plant, a gene of interest and its promoter are introduced into the plant protoplast, a plant cell without a cell wall, by incubating both in a medium containing polyethylene glycol.

The recombinant protoplast is cultivated on a sterile medium in the presence of growth regulators and nutrients.

The cells of the protoplast grow indefinitely, producing a mass of undifferentiated cells called a callus. Some cells of the callus, called totipotent cells, give rise to new shoots and roots, which can develop into a whole new plant.

Transgenic plants can also be created using the bacteria Agrobacterium tumefaciens, a gram-negative bacterium found in soil. This bacteria is a pathogen that normally causes disease in plants and contains a Ti -plasmid that can integrate into a plant cell genome.

The Ti plasmid has two regions of interest- T-DNA or transfer DNA region which can be inserted into the host cell genome and the virulence region to aid the