Agrobacterium tumefaciens is a soil bacterium known for its ability to transfer DNA to plants. This process leads to the formation of tumors, or galls, on the infected plants. It primarily affects dicotyledonous plants, which are characterized by having two seed leaves. The bacterium uses a specialized plasmid, called the Ti plasmid, to insert its DNA into the plant's genome. This genetic modification can cause the plant to produce nutrients that benefit the bacterium. Scientists have harnessed this natural mechanism for genetic engineering, allowing for the development of genetically modified organisms (GMOs) in agriculture.