Marie A. C. Langham,South Dakota State University
"Great fleas have little fleas upon their backs to bite 'em, And little fleas have lesser fleas, and so ad infinitum, . . . "
A Budget of ParadoxesAugustus de Morgan (1806-1871)
Microscopic organisms are unique and often unseen wonders that have as much (or more) diversity than macroscopic organisms. Since its invention, the microscope has served to focus our wonder and amazement at the microscopic world of the small, smaller, and smallest. Whether examining the root hairs on a plant, the spores of a fungus, or the organelles of a plant cell, the microscope allows your students to experience the intricacies of this hidden world that may seem unreal when simply viewed with diagrams or illustrations. Thus, the microscope is one of the most important tools in science laboratories, and it is essential in Plant Pathology where it is utilized in the identification of plant pathogens and their effects on plants.
Teaching students careful and appropriate procedures for using microscopes allows them to more easily utilize the instrument and helps protects the equipment from damage. An excellent source for teaching basic microscopy skills for both compound and dissecting microscopes can be found in Basic Microscopy -An Important Skill for Plant Pathologists by Melissa Riley at http://publish.apsnet.org/edcenter/K-12/NewsViews/Pages/2004_09.aspx in the Introductory Laboratory Exercises section of this Education Center. The exercise includes pictures of the microscopes with interactive labels as seen in Fig. 1 and Fig. 2.
Plant pathogens are ideal subjects for laboratory exercises to utilize or demonstrate microscopes. Would you like some ideas on how to use plant pathogens in a laboratory exercise? Check out the laboratory exercises in the K-12 Teacher's Guide to Lessons and Laboratories. There are exercises that utilize water molds, powdery mildews, nematodes, and other fungi to provide students with an introduction to the world of the microscope. Microscopes can even add a new dimension to things as mundane as table sugar and salt, and they will endow your students with a new insight into the world that surrounds them.
For additional information on microscopes and microscopy, try these websites:
Authored by James A. Sullivan, Cells Alive (http://www.cellsalive.com/) provides an impressive selection of micrographs.
At The Digital Learning Center for Microbe Ecology (http://commtechlab.msu.edu/sites/dlc-me/), you can visit the Microbe Zoo or meet the Microbe of the Month. Check out the Thanksgiving microbe. It's familiar to all plant pathologists.
At http Marly Cain's Amazing Micronautic Adventures is a blend of fun, creative activities, and learning assisted by Merlin, the web-site guide, that will appeal to many students .
The Brian J. Ford Science Website (http://www.sciences.demon.co.uk/whistmic.htm) provides The History of the Microscope including a picture of one of Leeuwenhoek's original microscopes.
At http://www.life.uiuc.edu/plantbio/cell/, The Virtual Cell provides an intimate view of a plant cell and its organelles and other structures.