APPENDIX B
for
"War of the Roses"

by
Melissa B. Riley
Department of Plant Pathology and Physiology
Clemson University

Guidelines for Mounting Specimens Including Spores
Reference: McCain, J.W. 1988. Use and care of the light microscope. In: Laboratory Exercises in Plant Pathology: An Instructional Kit. A.B.A.M. Baudoin, ed. APS Press: St. Paul, Minnesota. pp.1:8-1:12.

Mounting of specimens involves transferring them to microscope slides and preparing them for examination. Begin with clean slides and cover slips. Lens paper or lens paper plus water will suffice to clean most new slides, but it is more effective to dip slides in 70-95% ethanol and dry them with clean Kim-wipes.

1. The specimen may be mounted in a drop of water. Sterile or distilled water is a good mounting liquid but the mounts dry out quickly.
2. Mounting in a stain such as cotton blue can also be used to color pale specimens.

Mounting Procedure: Put a drop of mounting solution on the slide and place the specimen in the drop. Lower a cover slip onto the slide, being careful to avoid pushing the specimen to one side or out from under the cover slip. Avoid using too much mounting solution. Air bubbles can distort images under the microscope. It is sometimes difficult to recognize air bubbles. Adding the cover slip carefully will keep the number of bubbles to a minimum as would using specimens that are not too thick. Sometimes gentle pressure with a dissecting needle will push the bubbles out from under the cover slip. However, surface features of certain specimens, such as spines on a fungal spore, may actually be easier to see when they are against or in an air bubble. Also, if you focus on the edge of an air bubble, the specimen should almost be in focus, too, needing only a partial turn of the fine-focus knob of the microscope.

Scrape Mounts. Small, loose items, such as fungal spores, may simply be scraped from the surface of a leaf or other plant part or from the surface of an agar culture with a scalpel. Dry spores may stick to the tool more readily if you dip the tool into the drop of mounting liquid or stain that should be waiting on a microscope slide. Be careful not to disrupt the structure any more than necessary--gently tease spores off of the leaf surface or culture plate.

Cellophane Tape Method. Cellophane tape can be used as another way to transfer samples to a microscope slide. It has the advantage that structures will more or less retain their original position relative to each other; for instance, chains of spores will remain chains.

Variations:

1. Make a loop of a piece of tape or use a piece of double-stick tape (adhesive on both sides). Attach a cover glass to one side of the tape. Trim off excess tape if necessary. Touch the specimen or culture plate with the exposed sticky side of the tape so that spores or other objects become attached to the tape. Lift the tape with cover glass from the specimen or culture, and lower onto a drop of mounting liquid on a slide (Figure 1A).
2. Press a length of double-stick tape gently against the culture or spore-bearing plant material. Then attach it to a microscope slide with the spore-bearing surface up. Add a drop of mounting liquid and a cover slip (Figure 1B).
3. Press the sticky side of single sided cellophane tape gently onto the specimen and then mount the tape with the adhering spores and hyphae down in a drop of water or stain on a slide such that the tape acts as a cover slip (Figure 1C).