At the turn of the century Agrobacterium tumefaciens was identified as the causal agent in crown gall disease in dicotyledonous plants.
Agrobacterium tumefaciens is most widely known for causing crown gall disease that affects many dicotyledonous (broad-leaved) plants; another strain called biovar 3 causes crown gall disease in grapvines.
Agrobacterium is well known for its ability to transfer DNA between itself and plants, and for this reason it has become an important tool for plant improvement by genetic engineering.
Taxonomic note: The Agrobacteriumgenus is quite heterogeneous, recent taxonomic studies have reclassified all of the Agrobacteriumspecies in to new genera, such as Ruegeria, Pseudorhodobacter and Stappia.
