Field Science Challenge #5 – Pathogens, Parasites and Plants

Plants, like people, can get really sick.  Because plants are primary producers, the only organisms able to make food for the world, many scientists study plant health in both agricultural systems and natural eco-systems.  Dr. Ian Miller of Princeton University is a RMBL scientist who specializes in plant pathogens as well as human epidemiology.  Here in the Rockies, Ian’s research focuses on Lewis Flax (Linum Lewisii) and its pathogen, a fungus called flax rust (Melampsora lini).  Ian would like to know if climate change is affecting the infectiousness and aggressiveness of plant pathogens.  However, during the current COVID-19 pandemic Ian, and other scientists with expertise in disease have been called upon to bring their knowledge of pathology to help fight this pandemic in human communities.  Understanding the interactions of the disease triangle can help us consider which actions can be taken to break or weaken the hold of disease, whether that be in plants or people! 

Recorded Live Lab Chat with Ian Miller

What We’d Like to Find Out: Which plant pathogens and parasites are present where you live?  What environmental factors impact plants abilities to be healthy?  Does climate change impact the spread of plant pathogens?  

What You’ll Need:  

What To Do:  

  1. Find some plant pathogens or parasites!  Plant pathogens are bacteria, viruses, and other microorganisms that cause disease, and parasites are organisms that live on plants at the expense of the plant.  
  1. Take a walk/hike where you live.  Look at the plants around you closely.  Do you notice signs of insect invaders, illnesses or injuries?  
  1. If you would like some ideas of what to find, use thParasite and Pathogen Pursuit Sheet that has pictures you can match to pathogens you find, and then you can tally how many of each type you see.  
  1. Once you have found a pathogen of interest, take a moment to make some observations and consider the following questions:  
  1. What is the host? Is there just one host, or do you see the disease on multiple hosts? What can we infer about the pathogens specificity? 
  1. Are all of the hosts in the area you observed diseased? Why do you think this is? What environmental factors could be in play? 
  1. How did the pathogen get to the host? How does that relate to any spatial patterns of disease? 
  1. Can you identify your plant and its pathogen?  You may need to do a little research to find out what it is, how it spreads and whether it is sensitive to environmental conditions.  You may also want to investigate what can weaken or break the disease in this plant host.  For those of you living in Colorado, if you want help with diagnosing and fighting plant disease in your neighborhood, here are instructions for sending infected plant samples to CSU cooperative extension for diagnoses 

Please Remember (Research Rules & Ethics): When examining plant parasites and diseases, be aware that you may become a vector, something that spreads the disease.  Prevent the transport infections, fungus, etc. from place to place by washing your hands and disinfecting both field tools and shoes that may have come in contact with a plant pathogen.   

What Happened?  Tell Us About It!  If you find a pathogen of particular interest or abundance, please take a picture and send it to usAlso, if you have questions about plant pathogens (or human pandemics), watch the recorded lab chat with Dr. Ian Miller.   

So What? Next Steps: Keep track of this plant pathogen from year to year.  How does it change, grow or decrease?  How is the environment changing? What factors seem to be impacting the pathogen over time? Can you find this same pathogen in different areas to compare to your original finding?  Let us know if this turns into a long-term research project!