Plants are the major food source for animals and human. The most common plant pathogens are bacteria, fungi, and viruses. Students will form several groups to search information on the major plant pathogens in human history and learn about the factors that influence plant pathogens to attack plants. Students will also learn how to recognize symptoms caused by various plant pathogens and methods of plant disease investigation. There will be discussions on plant disease detection and diagnosis, plant pathogen-host interactions and development of disease resistant plants using transgenic techniques. Students will explore the origins of plant pathogens and their evolution, agricultural crops as food, transgenic crops and food safety issues related to plant diseases. This freshmen seminar is suitable for both life science and nonlife science majors.