PLPA 200 Lecture Notes - Lecture 7: Downy Mildew, Plant Pathology, Hemileia Vastatrix
Document Summary
The major issue for this week is exotic vs. endemic pathogens. You may think that all plant pathogens are a little exotic, but really, just some of them are. In the rst case, where a new host is introduced to an area, and becomes infected by a pathogen that already exists there, we say that the pathogen is endemic to that area, and the new host is exotic. In the second case, where a new pathogen is introduced, we say that the pathogen is exotic and the host is endemic to the area. Endemic means that that organism is native to an area, or has existed there for a long time. Exotic means that that organism is a relative new comer to that area. In both of these cases the host and the pathogen evolved separately, thus the host did not have a chance to develop resistance to the pathogen,