Damping-off disease in lettuce seedlings: a didactic-experimental model for teaching Koch's postulates

Abstract

The teaching of the scientific method is facilitated by simple but rigorous experimental practices. Koch's postulates represent a historical breakthrough in the development of the scientific method. These postulates are a guide or protocol to follow in order to find empirically that a particular microorganism is the causative agent of an infectious disease in a susceptible organism. The present work shows that the pathology of lettuce seedlings damping-off is an appropriate experimental model to teach these principles. It was possible to use low-cost materials with a simple, reproducible and free risk to human health methodology, with easy applicability in any high school or university classroom.