Which method is commonly used for plant transformation?

Agrobacterium tumefaciens-mediated transformation is a widely recognized method for introducing new genetic material into plant cells. This bacterium has a natural ability to transfer DNA to plant cells, which allows for the integration of desired traits directly into the plant genome. During this process, researchers utilize the virulence genes of Agrobacterium that facilitate the transfer of a specific segment of DNA, known as T-DNA, into the host plant's cells. This method is highly efficient and can be used with a variety of plant species, making it a preferred technique in agricultural biotechnology for developing genetically modified organisms (GMOs).

The other methods mentioned, such as direct seed planting, hydroponics cultivation, and natural pollination, do not involve the manipulation of plant genetic material in the same way. Direct seed planting is simply a method of establishing plants in the ground from seeds without altering their genetic makeup. Hydroponics cultivation refers to a soilless growing technique that does not pertain to genetic transformation, while natural pollination is a biological process involving the transfer of pollen from one flower to another for reproduction, not for the introduction of new genetic traits. Thus, the targeted nature and effectiveness of Agrobacterium tumefaciens-mediated transformation in