Science Buddies: "Ask an Expert"

What happens when microbes, or pathogens, invade plant cells? Do they target the cytoplasm, mitochondria, or nucleus? Also, do the plants get "sick" because these pathogens destroy the genetic information of these plants?

Hi, thanks for your question.

Since there is such a huge variety of microorganisms falling under the title of "pathogen", each will react differently when infecting living plant cells. For example, some bacteria will infect the plant cell and produce toxins that result in host cell death, or produce enzymes that destroy plant cell walls. On the other hand, it is unlikely for many types of viruses to naturally penetrate plant cells, but when they do, the virus survives in the plant's generative and germ cells. Plant cells are more well-protected than animal cells due to their cell wall, however many plants will die due to a pathogenic infection.