Q: I need to know how to grow a bacterium to infect a healthy plant, and then try and cure it with beta carotene. Agrobacterium tumefaciens had been suggested but we cannot find the bacteria. Is there anything that I can feed the plant to make it unhealthy? We are using Sunflower seeds as our specimen.

A: Sounds like a fascinating project!

You can buy Agrobacterium tumefaciens from Carolina Biological Supply BUT you have to have a special permit to get the bacteria. It may take 30 days to receive the permit. You can read the details on their site.

This site gives more information on the bacteria

crown gall on forsythia

itself.