crown gall disease is caused which of the following pathogen

1. virus
2. bacteria
3. fungi
4. protozoans

Hi student
Crown gall disease(Plant disease) is caused by a particular type of bacteria viz. Agrobacterium tumifaciens.
In this disease, the over growth of root and at the base, occur in susceptible plants.

Hi student
Crown gall disease(Plant disease) is caused by a particular type of bacteria viz. Agrobacterium tumifaciens.
In this disease, the over growth of root and at the base, occur in susceptible plants.

The correct answer is (2) bacteria.

Agrobacterium tumefaciens is the causal agent of crown gall disease. It is a rod-shaped, Gram-negative soil bacterium.
A. tumefaciens includes the nitrogen-fixing legume symbionts. Unlike the nitrogen-fixing symbionts, tumor-producing Agrobacterium species are pathogenic and do not benefit the plant. The wide variety of plants affected by Agrobacterium makes it of great concern to the agriculture industry.