Multiple choice Which bacterium is mostly used in r-DNA technology? E.coli Agrobacterium tumefaciens Mycobacterium leprae Green sulphur bacteria Reveal answer Fill a bubble to check yourself B Correct answer Explanation Plant transformation mediated by Agrobacterium tumefaciens, a soil plant pathogenic bacterium, has become the most used method for the introduction of foreign genes into plant cells and the subsequent regeneration of transgenic plants.