Agrobacterium: An Economically Significant Plant Pathogen

Agrobacterium is not only an important bacterium in genetic engineering for gene transformation but also an important plant pathogenic bacterium. Economically significant diseases caused by Agrobacterium include crown galls in apples and pears, caused by A. tumefaciens. Agrobacteria are gram-negative, rod-shaped bacteria belonging to the class Alphaproteo bacteria and the family Rhizobiaceae. These Agrobacterium strainscan be isolated from galls grown on MacConkey agar Carrot-disk and potato-disk bioassays can be used for pathogenicity tests. Other major crops, including crown gall disease caused by Agrobacterium, include many woody plants, primarily stone fruits, pome fruits, willows, and grapes. In this study, we critically review aspects of Agrobacterium such as its taxonomy, geographical distribution, transmission, host range, symptomatology, pathogenicity, biology, epidemiology, survival, and economic importance. Important components of crown gall disease management, such as cultural, mechanical, chemical, biological, and resistant/tolerant varieties also form the text of the present review.